From rrezaian at motorola.com Mon Jun 1 01:01:36 2009 From: rrezaian at motorola.com (Russell Rezaian) Date: Sun, 31 May 2009 20:01:36 -0500 Subject: [time-nuts] Datum 9200 etal In-Reply-To: <825632.50603.qm@web55301.mail.re4.yahoo.com> References: <825632.50603.qm@web55301.mail.re4.yahoo.com> Message-ID: Hi Mike, I have been thinking about this particular idea for a few months now. I've read a number of references that mentioned that at one point in the past TrueTime made a GPS antenna that would drive the 468 clocks with a signal that resembled the signal that came from the GOES satellites. I don't think they made very many of them. I've seen references to them on the net in various places, but I've never seen one myself. However, reading about these started me thinking. How hard would it be to build a similar gizmo oneself? Probably not impossible. The GOES code was fairly well documented. Only problem is that I am a software person, so I am frighteningly clueless about how hard this would actually be from a hardware perspective. I know the 468 clocks used down converter antennas, so one would need to generate a carrier at the frequency the clocks expected and modulate that. So, the question is, has anyone else already played with this idea? More importantly has anyone who knows more about hardware than I do given this any serious thought? -- Russell At 7:42 AM -0700 2009/05/31, michael castellano wrote: >2) this is an old one: like most of us, I have a Truetime 486DC >that is now a pretty paperweight (In fact I have 3 here). Has ANYONE >figured out how to do SOMETHING with it? Maybe a T/C translator, a >stand alone clock (not so accurate, I know) or how making it into a >remote readout? From wje at quackers.net Mon Jun 1 01:23:10 2009 From: wje at quackers.net (wje) Date: Sun, 31 May 2009 21:23:10 -0400 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <4A232D7E.1070009@quackers.net> This is a pull from a Lucent unit used to provide timing for cell sites. I have a couple myself. The board is primarily a 10Mhz to 15Mhz converter. It also has some failover logic. Typically two independent units were installed in one plugin chassis. The D connector has power in and status in, and provides status out. One unit is set as the primary and the other as the secondary via signals on the connector. The secondary then monitors the status of the primary and will switch to primary if the other fails. The TNC connectors provide raw 10Mhz from the FRS, a buffered 10Mhz, and synthesized 15Mhz. I did at one time have the connector pinout info, but since the board is fairly useless, I'm not sure I kept it. It does have some nice TNC connectors and a nice crystal filter, if you happen to need a 15Mhz filter. Bill Ezell ---------- They said 'Windows or better' so I used Linux. GandalfG8 at aol.com wrote: > Bob, Fluke.1, is selling these on Ebay, for example item # 290313671907, > and supplies the FRS module itself with an interface board containing the > FRS connector, plus another PCB containing a 15MHz oscillator and assorted > other parts that the FRS interface board plugs into. > > Connecting up the FRS itself via the 10 way header on the interface board > is simple enough, most connections are marked and others easily traced, but > there's no information available regarding the other PCB. > > Does anyone have any information regarding the purpose of this board > and/or connection details for the fitted 25 way D type and TNC connectors? > Any information on the functions of the various jumper pins would also be > appreciated. > > regards > > Nigel > GM8PZR > > From GandalfG8 at aol.com Mon Jun 1 01:30:12 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sun, 31 May 2009 21:30:12 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: In a message dated 01/06/2009 02:23:46 GMT Daylight Time, wje at quackers.net writes: I did at one time have the connector pinout info, but since the board is fairly useless, I'm not sure I kept it. It does have some nice TNC connectors and a nice crystal filter, if you happen to need a 15Mhz filter. ----------- Hi Bill I did realise, after my posted request, that what was described in the auction as a 15MHz oscillator was actually a 15MHz filter with 36KHz bandwidth. Not sure that I need one either:-), but if you do still have the connector pinout I'd be grateful for a copy. regards Nigel GM8PZR From pete at petelancashire.com Mon Jun 1 03:32:56 2009 From: pete at petelancashire.com (Pete Lancashire) Date: Sun, 31 May 2009 20:32:56 -0700 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: References: Message-ID: Thanks to those that have replied. It looks like just about everyone recommended the Thunderbolt. But before I invest .. any negative comments ? Specs, reliability, or ? -pete From jim77742 at gmail.com Mon Jun 1 05:14:43 2009 From: jim77742 at gmail.com (Jim Palfreyman) Date: Mon, 1 Jun 2009 15:14:43 +1000 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: References: Message-ID: Nice little unit and *great* value for money. My power supply (from the group buy) died - but that's another issue completely. The unit itself I have no complaints about. However, if you have plenty of money and want to go more up market try a CNS Mark II: http://www.cnssys.com/cnsclock/CNSClockII.php 2009/6/1 Pete Lancashire > Thanks to those that have replied. It looks like just about everyone > recommended the Thunderbolt. But before I invest .. any negative > comments ? Specs, reliability, or ? > > -pete > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From quenbob5 at pacbell.net Mon Jun 1 05:51:59 2009 From: quenbob5 at pacbell.net (Bob Q) Date: Sun, 31 May 2009 22:51:59 -0700 Subject: [time-nuts] HP/Agilent 5335A Message-ID: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> I'm thinking of buying an HP 5335A to upgrade from my old HP 5315A. I notice prices on *Bay range from $100 (missing button on power switch) to $2100. Any thoughts on what a fair price for one is? Thanks, Bob Q. From BNeubig at t-online.de Mon Jun 1 06:53:22 2009 From: BNeubig at t-online.de (Bernd T-Online) Date: Mon, 01 Jun 2009 08:53:22 +0200 Subject: [time-nuts] What type of Crystal? Message-ID: <4A237AE2.1020707@t-online.de> I am wondering why my post did not go through yesterday. Here it is again: For an OCXO you can determine whether it is an AT, BT or SC cut crystal by looking at the frequency difference between warm-up and after. Jim wrote earlier, that his "10544 osc is sitting about 1.5KHz LOW at room temp and then increases in freq at warmup (OVEN temp rising)". 1.5 kHz = 150 ppm @ 10 MHz. 1. A BT cut crystal has a second order tempco of approx. -4*10^-8 per K^2 with reference to the turn-over temperature. Assuming an oven temperature of around 85?C, makes a temp difference to room temp of abt. 60K: (60K)^2*(0.04ppm/K^2) = 144 ppm = 1.44 kHz. This matches closely to Jims measurement. 2. An AT cut crystal has a frequency vs. temperature response described by a 3rd order parabola with its symmetry point around 25?C~35?C. Without going into the math in detail: A cut angle with a UTP of 85?C has an offset at 85?C compared to 25?C of about -45 ppm. This is much less than Jim's observation, and the direction of the frequeency change is opposite to the observed one. 3. An SC-cut crystal also has a frequency vs. temperature response described by a 3rd order parabola with an inflection (symmetry) temperature of around 95?C. But the SC-cut f(T) response has a much flatter curvature than an AT-cut (see the HP magazine article cited earlier). An OCXO with an SC-cut crytal operating at 85?C shows about -18ppm offset at room temperature compared to the frequency at assumed TOP of 85?C. This is a much smaller amount than Jim's measurement. Therefore it is easy to conclude, that Jim's 10544 uses a BT-cut crystal. Best regards Bernd Neubig DK1AG __________________ AXTAL GmbH & Co. KG www.axtal.com Ed Palmer wrote: > The recent discussion regarding the type of crystal in the HP 10544A > brought this question to mind. We're always coming across unknown > oscillators. Usually we can figure out the pinouts and voltages. Then > we can measure stability, aging, etc. But are there any tricks to > figure out what type of crystal is in the oscillator? How can you > detect the differences between AT, BT, SC, etc? > I think that AT crystals have a broader tuning range than SC and that > when warming up AT crystals tend to overshoot the final frequency and > fall back. Are these generalizations correct? Are there other tricks > to help differentiate the crystal types? > Ed From robert8rpi at yahoo.co.uk Mon Jun 1 07:00:23 2009 From: robert8rpi at yahoo.co.uk (Robert Atkinson) Date: Mon, 1 Jun 2009 07:00:23 +0000 (GMT) Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: <272224.77399.qm@web27101.mail.ukl.yahoo.com> The CNS-II is very nice, but is more aligned with NTS applications than precision frequency. Also by the time you add an OCXO the cost is well over $2000. The Jackson Labs < http://www.jackson-labs.com/index.html > Fury or Firefly would be a better comparison to the Thunderbolt. Said is a regular poster here. Robert G8RPI. --- On Mon, 1/6/09, Jim Palfreyman wrote: > From: Jim Palfreyman > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > To: "Discussion of precise time and frequency measurement" > Date: Monday, 1 June, 2009, 6:14 AM > Nice little unit and *great* value > for money. My power supply (from the > group buy) died - but that's another issue completely. The > unit itself I > have no complaints about. > > However, if you have plenty of money and want to go more up > market try a CNS > Mark II: > > http://www.cnssys.com/cnsclock/CNSClockII.php > > > > 2009/6/1 Pete Lancashire > > > Thanks to those that have replied. It looks like just > about everyone > > recommended the Thunderbolt. But before I invest .. > any negative > > comments ? Specs, reliability, or ? > > > > -pete > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From magnus at rubidium.dyndns.org Mon Jun 1 08:30:54 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Mon, 01 Jun 2009 10:30:54 +0200 Subject: [time-nuts] HP/Agilent 5335A In-Reply-To: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> References: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> Message-ID: <4A2391BE.8010301@rubidium.dyndns.org> Bob Q skrev: > I'm thinking of buying an HP 5335A to upgrade from my old HP 5315A. I notice prices on *Bay range from $100 (missing button on power switch) to $2100. Any thoughts on what a fair price for one is? Being a proud owner of a HP 5335A I would say that if you find a good one in the 200-300 USD range I think you would be happy. It's a good universal counter and not very hard to work with. While I have better counters in the lab (SR-620, HP5370B, CNT-90 among others) I still like the much more intuitive interface of the 5335A. I would not pay more than 500 USD unless I badly needed one NOW. The HP 5315A is of the same era, and uses the same MRC chip (also used in HP 5334A and I suspect 5314A), but lacks the interpolators which brings it up to 1 ns timing resolution. I gave a HP 5315A away yesterday to a friend which is without a counter at all, I hope it will be useful to him. Cheers, Magnus From phill.r1 at btinternet.com Mon Jun 1 10:23:37 2009 From: phill.r1 at btinternet.com (Roy Phillips) Date: Mon, 1 Jun 2009 11:23:37 +0100 Subject: [time-nuts] HP/Agilent 5335A In-Reply-To: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> References: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> Message-ID: <186E0ADC434042698AC5129351DCBC5B@LapTop> Bob I bought the HP 5335A with missing power ON/OFF button (I'm still looking for one to replace it), but otherwise it was in excellent order. This was offered by a Military Surplus dealer in the UK, and I bought it for UK ?102 (? US $150). Some of the "up-market" dealers are offering this model for serious money ! The HP 5335A is well made and has provision for a TXCO (option 001), either the 10811 & 10554 can be fitted. I happened to have a 10811 and it is installed and works well. Apart from the inputs being good for 200 MHZ, it has other measurement and stats. facilities which are superior to the 5334A or B. The one I have is a late model with improved triggering selection at the rear panel. The Papst fan is rather noisy, as was my subject recently. Otherwise - good luck. Roy ----- Original Message ----- From: "Bob Q" To: Sent: Monday, June 01, 2009 6:51 AM Subject: [time-nuts] HP/Agilent 5335A > I'm thinking of buying an HP 5335A to upgrade from my old HP 5315A. I > notice prices on *Bay range from $100 (missing button on power switch) to > $2100. Any thoughts on what a fair price for one is? > Thanks, > Bob Q. > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From jra at febo.com Mon Jun 1 12:32:48 2009 From: jra at febo.com (John Ackermann N8UR) Date: Mon, 01 Jun 2009 08:32:48 -0400 Subject: [time-nuts] HP/Agilent 5335A In-Reply-To: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> References: <002801c9e27d$15382440$1801a8c0@BOBCEL1R7> Message-ID: <4A23CA70.9060703@febo.com> I picked up a really nice one with 10811A at the Dayton Hamvention for $125, which was probably too good to be repeatable. Last year a friend picked up three non-working but repairable for <$100 each. Probably anything under $250 for a working unit isn't a bad deal. Also, don't underestimate the 5334 counters. They are very capable, though they don't have all the math and statistics functions of the '35, they are only 1U in height *and have no fan!!!*, and I've bought several via eBay for $150 or less. YMMV... John ---- Bob Q wrote: > I'm thinking of buying an HP 5335A to upgrade from my old HP 5315A. I notice prices on *Bay range from $100 (missing button on power switch) to $2100. Any thoughts on what a fair price for one is? > Thanks, > Bob Q. > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From df6jb at ulrich-bangert.de Mon Jun 1 14:29:59 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Mon, 1 Jun 2009 16:29:59 +0200 Subject: [time-nuts] Z3805 / MTI 260-0624-C Message-ID: <2D17AB46986442B99928FB3242BEADAF@athlon> Gents, I just bought a Z3805 (similar to Z3801/Z3816 but with some differences...) from Chinese seller fluke.I. 1) Has anyone of you a link to a Z3805 manual? The Symmetricon pages have not. 2) This beast is equipped with a MTI 260-0624-C DOCXO. The MTI pages do not list the option "0624". Has anyone of you an idea what this spec stands for? Thanks in advance for your help. Ulrich Bangert www.ulrich-bangert.de Ortholzer Weg 1 27243 Gross Ippener From jltran at worldnet.att.net Mon Jun 1 14:40:00 2009 From: jltran at worldnet.att.net (J. L. Trantham) Date: Mon, 1 Jun 2009 09:40:00 -0500 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: Message-ID: <3B34BD56CDA44021B5C227454F6961FA@S0028384766> Pete, I have purchased units via the 'group buy' and directly from Bob Mokia (fluke.l). One of the 'group buy' units, powered by the accompanying 'group buy' power supply, died after being left on for a couple of days (as I recall). I still have it disassembled in a box in line on my 'to do list' of things to fix. I was suspicious that the power supply might have been the culprit, perhaps facilitated by frequent power outages (i.e. transients), even though the power supply still works. Since then, I have only powered the units with linear power supplies with no problems. Joe -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Pete Lancashire Sent: Sunday, May 31, 2009 10:33 PM To: time-nuts at febo.com Subject: [time-nuts] Thunderbolt - any negatives ? Thanks to those that have replied. It looks like just about everyone recommended the Thunderbolt. But before I invest .. any negative comments ? Specs, reliability, or ? -pete _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From ed_palmer at sasktel.net Mon Jun 1 14:53:03 2009 From: ed_palmer at sasktel.net (Ed Palmer) Date: Mon, 01 Jun 2009 08:53:03 -0600 Subject: [time-nuts] What type of Crystal? In-Reply-To: <4A237AE2.1020707@t-online.de> References: <4A237AE2.1020707@t-online.de> Message-ID: <4A23EB4F.80509@sasktel.net> Thanks for the info Bernd. This is exactly the type of data I was hoping to get. I also have a 10544A that starts out about 1 - 1.5 KHz low and it never made any sense to me because I thought it was an AT xtal. Now I can check through my junk box oscillators and fill in some blanks. Thanks! By the way, I had a message disappear a week or so ago. I wonder what's going on? Ed Bernd T-Online wrote: > > I am wondering why my post did not go through yesterday. > Here it is again: > > For an OCXO you can determine whether it is an AT, BT or SC cut crystal > by looking at the frequency difference between warm-up and after. > > Jim wrote earlier, that his "10544 osc is sitting about 1.5KHz > LOW at room temp and then increases in freq at warmup (OVEN > temp rising)". 1.5 kHz = 150 ppm @ 10 MHz. > 1. A BT cut crystal has a second order tempco of approx. -4*10^-8 per > K^2 with reference to the turn-over temperature. Assuming an oven > temperature of around 85?C, makes a temp difference to room temp of abt. > 60K: (60K)^2*(0.04ppm/K^2) = 144 ppm = 1.44 kHz. This matches closely > to Jims measurement. > 2. An AT cut crystal has a frequency vs. temperature response described > by a 3rd order parabola with its symmetry point around 25?C~35?C. > Without going into the math in detail: A cut angle with a UTP of 85?C > has an offset at 85?C compared to 25?C of about -45 ppm. This is much > less than Jim's observation, and the direction of the frequeency change > is opposite to the observed one. > 3. An SC-cut crystal also has a frequency vs. temperature response > described by a 3rd order parabola with an inflection (symmetry) > temperature of around 95?C. But the SC-cut f(T) response has a much > flatter curvature than an AT-cut (see the HP magazine article cited > earlier). An OCXO with an SC-cut crytal operating at 85?C shows about > -18ppm offset at room temperature compared to the frequency at assumed > TOP of 85?C. This is a much smaller amount than Jim's measurement. > > Therefore it is easy to conclude, that Jim's 10544 uses a BT-cut crystal. > > Best regards > > Bernd Neubig > DK1AG > __________________ > AXTAL GmbH & Co. KG > www.axtal.com > > > Ed Palmer wrote: >> The recent discussion regarding the type of crystal in the HP 10544A >> brought this question to mind. We're always coming across unknown >> oscillators. Usually we can figure out the pinouts and voltages. >> Then >> we can measure stability, aging, etc. But are there any tricks to >> figure out what type of crystal is in the oscillator? How can you >> detect the differences between AT, BT, SC, etc? >> I think that AT crystals have a broader tuning range than SC and that >> when warming up AT crystals tend to overshoot the final frequency and >> fall back. Are these generalizations correct? Are there other >> tricks >> to help differentiate the crystal types? >> Ed > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From jra at febo.com Mon Jun 1 15:01:32 2009 From: jra at febo.com (John Ackermann N8UR) Date: Mon, 01 Jun 2009 11:01:32 -0400 Subject: [time-nuts] What type of Crystal? In-Reply-To: <4A23EB4F.80509@sasktel.net> References: <4A237AE2.1020707@t-online.de> <4A23EB4F.80509@sasktel.net> Message-ID: <4A23ED4C.6080200@febo.com> Ed Palmer wrote: > By the way, I had a message disappear a week or so ago. I wonder what's > going on? I'm not aware of any issues with the mail list system, but incoming messages do go through a spam and antivirus filter, so it's possible that some messages get caught in that. The filtering system doesn't get too many false positives, but it can happen. John From phill.r1 at btinternet.com Mon Jun 1 15:33:57 2009 From: phill.r1 at btinternet.com (Roy Phillips) Date: Mon, 1 Jun 2009 16:33:57 +0100 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: <3B34BD56CDA44021B5C227454F6961FA@S0028384766> References: <3B34BD56CDA44021B5C227454F6961FA@S0028384766> Message-ID: <1284D7BAD956434C9FA35B20CF5E6778@LapTop> Joe and others I would recommend using a linear PSU, I have some made by a Company called Lascar (perhaps a different name in the States). These are not much larger than the Thunderbolt itself with a little more height. They have three separate VS./Rags, 5 volts and +15/-15 volt supplies of sufficient capacity - all with trim-pots. Mine has been working for at least one year non-stop - and you can be confident that it will not blown up, unlike some switched supplies. Roy ----- Original Message ----- From: "J. L. Trantham" To: "'Discussion of precise time and frequency measurement'" Sent: Monday, June 01, 2009 3:40 PM Subject: Re: [time-nuts] Thunderbolt - any negatives ? > Pete, > > I have purchased units via the 'group buy' and directly from Bob Mokia > (fluke.l). One of the 'group buy' units, powered by the accompanying > 'group > buy' power supply, died after being left on for a couple of days (as I > recall). I still have it disassembled in a box in line on my 'to do list' > of things to fix. > > I was suspicious that the power supply might have been the culprit, > perhaps > facilitated by frequent power outages (i.e. transients), even though the > power supply still works. Since then, I have only powered the units with > linear power supplies with no problems. > > Joe > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of Pete Lancashire > Sent: Sunday, May 31, 2009 10:33 PM > To: time-nuts at febo.com > Subject: [time-nuts] Thunderbolt - any negatives ? > > Thanks to those that have replied. It looks like just about everyone > recommended the Thunderbolt. But before I invest .. any negative > comments ? Specs, reliability, or ? > > -pete > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From hmurray at megapathdsl.net Mon Jun 1 16:47:58 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Mon, 01 Jun 2009 09:47:58 -0700 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: Message from "Roy Phillips" of "Mon, 01 Jun 2009 16:33:57 BST." <1284D7BAD956434C9FA35B20CF5E6778@LapTop> Message-ID: <20090601164759.0EE94BCE9@ip-64-139-1-69.sjc.megapath.net> phill.r1 at btinternet.com said: > I would recommend using a linear PSU, I have some made by a Company > called Lascar (perhaps a different name in the States). These are not > much larger than the Thunderbolt itself with a little more height. > They have three separate VS./Rags, 5 volts and +15/-15 volt supplies > of sufficient capacity - all with trim-pots. Mine has been working > for at least one year non-stop - and you can be confident that it > will not blown up, unlike some switched supplies. Is there something I don't understand in this area? What makes a linear supply more reliable than a switcher? My first guess would be a switcher would be more reliable because it would run cooler. That's probably assuming the same amount of design effort which is probably not a valid assumption if I'm comparing a brand-X linear with a brand-Z switcher. A quick glance at the general construction might give a better answer. -- These are my opinions, not necessarily my employer's. I hate spam. From pete at petelancashire.com Mon Jun 1 17:07:29 2009 From: pete at petelancashire.com (Pete Lancashire) Date: Mon, 1 Jun 2009 10:07:29 -0700 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: <1284D7BAD956434C9FA35B20CF5E6778@LapTop> References: <3B34BD56CDA44021B5C227454F6961FA@S0028384766> <1284D7BAD956434C9FA35B20CF5E6778@LapTop> Message-ID: <8ee95ff95a0d554a4605bc824e604fcc.squirrel@petelancashire.com> Anyone running with a power supply with built in UPS ? A long time ago (>15yrs) I did project that for a supply did a/c line -> battery -> +5/+12/-12. A side advantage was great isolation. Can't remember the supply vendor tho' ... -pete > Joe and others > I would recommend using a linear PSU, I have some made by a Company called > Lascar (perhaps a different name in the States). These are not much larger > than the Thunderbolt itself with a little more height. They have three > separate VS./Rags, 5 volts and +15/-15 volt supplies of sufficient > capacity - all with trim-pots. Mine has been working for at least one year > non-stop - and you can be confident that it will not blown up, unlike some > switched supplies. > Roy > > > ----- Original Message ----- > From: "J. L. Trantham" > To: "'Discussion of precise time and frequency measurement'" > > Sent: Monday, June 01, 2009 3:40 PM > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > > >> Pete, >> >> I have purchased units via the 'group buy' and directly from Bob Mokia >> (fluke.l). One of the 'group buy' units, powered by the accompanying >> 'group >> buy' power supply, died after being left on for a couple of days (as I >> recall). I still have it disassembled in a box in line on my 'to do >> list' >> of things to fix. >> >> I was suspicious that the power supply might have been the culprit, >> perhaps >> facilitated by frequent power outages (i.e. transients), even though the >> power supply still works. Since then, I have only powered the units >> with >> linear power supplies with no problems. >> >> Joe >> >> -----Original Message----- >> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On >> Behalf Of Pete Lancashire >> Sent: Sunday, May 31, 2009 10:33 PM >> To: time-nuts at febo.com >> Subject: [time-nuts] Thunderbolt - any negatives ? >> >> Thanks to those that have replied. It looks like just about everyone >> recommended the Thunderbolt. But before I invest .. any negative >> comments ? Specs, reliability, or ? >> >> -pete >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From phk at phk.freebsd.dk Mon Jun 1 17:10:26 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 01 Jun 2009 17:10:26 +0000 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: Your message of "Mon, 01 Jun 2009 10:07:29 MST." <8ee95ff95a0d554a4605bc824e604fcc.squirrel@petelancashire.com> Message-ID: <3013.1243876226@critter.freebsd.dk> In message <8ee95ff95a0d554a4605bc824e604fcc.squirrel at petelancashire.com>, "Pet e Lancashire" writes: >Anyone running with a power supply with built in UPS ? > >A long time ago (>15yrs) I did project that for a supply did >a/c line -> battery -> +5/+12/-12. A side advantage was great >isolation. mini-box.com has a small "12V UPS" board, havn't tried it, but a friend did and it works fine. I've run my timing stuff off a "battery-backed power-supply" normally used for firealarms. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From SAIDJACK at aol.com Mon Jun 1 17:17:25 2009 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Mon, 1 Jun 2009 13:17:25 EDT Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: Hi there, A switcher has much more stresses on the components, since it usually switches the primary side rectified 110/220V high-voltage across a transformer. Thus the switching FET has to be very high voltage capable (about ~170V DC in the US), and the second component under stress is the primary high voltage capacitor, because it sees a very fast AC switching current on it (current draw is on when the FET is on, and off when the Fet is off). Also there has to be a fast snubber network to prevent the back-emf from destroying the primary Fet with over-voltage. A linear supply has none of these fast current/voltage transients on it, only a couple of diodes switching the 60Hz secondary onto a capacitor at low voltage. A secondary concern is thermally induced stress, switchers will usually be packed into a very small enclosure with very high power capability/density. This is not possible for linear supplies, since the transformer size will usually determine overall sizing. Compare a Laptop power supply size (usually these have between 40W and 90W rating!) to a similar rated linear supply. bye, Said In a message dated 6/1/2009 09:48:29 Pacific Daylight Time, hmurray at megapathdsl.net writes: Is there something I don't understand in this area? What makes a linear supply more reliable than a switcher? My first guess would be a switcher would be more reliable because it would run cooler. That's probably assuming the same amount of design effort which is probably not a valid assumption if I'm comparing a brand-X linear with a brand-Z switcher. A quick glance at the general construction might give a better answer. From GandalfG8 at aol.com Mon Jun 1 17:18:14 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Mon, 1 Jun 2009 13:18:14 EDT Subject: [time-nuts] Thunderbolt and UPS, Was any negatives ? Message-ID: In a message dated 01/06/2009 18:03:02 GMT Daylight Time, pete at petelancashire.com writes: Anyone running with a power supply with built in UPS ? A long time ago (>15yrs) I did project that for a supply did a/c line -> battery -> +5/+12/-12. A side advantage was great isolation. ----------- Probably the easiest way to do that for the Tbolt would be to generate pos and neg 12 volt supplies, either from a single or pair of transformers, with the pos 5 volt derived from the pos 12, and also use the supplies to trickle charge a couple of 12 volt sealed lead acid batteries. It would be easy enough to calculate ratings based on required battery running period and the battery on the neg 12 rail could be significantly lower capacity than that on the positive supply. regards Nigel GM8PZR From aa8k at comcast.net Mon Jun 1 17:44:56 2009 From: aa8k at comcast.net (Mike Naruta AA8K) Date: Mon, 01 Jun 2009 13:44:56 -0400 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: <8ee95ff95a0d554a4605bc824e604fcc.squirrel@petelancashire.com> References: <3B34BD56CDA44021B5C227454F6961FA@S0028384766> <1284D7BAD956434C9FA35B20CF5E6778@LapTop> <8ee95ff95a0d554a4605bc824e604fcc.squirrel@petelancashire.com> Message-ID: <4A241398.6050409@comcast.net> I have a house battery with a TAPR HPSDR LPU < http://www.tapr.org/kits_lpu.html > A little overkill, but it's quiet and a back up supply for the ones in my Open HPSDRs. Mike - AA8K Pete Lancashire wrote: > Anyone running with a power supply with built in UPS ? > > A long time ago (>15yrs) I did project that for a supply did > a/c line -> battery -> +5/+12/-12. A side advantage was great > isolation. > > Can't remember the supply vendor tho' ... > > -pete > > From holrum at hotmail.com Mon Jun 1 18:02:28 2009 From: holrum at hotmail.com (Mark Sims) Date: Mon, 1 Jun 2009 18:02:28 +0000 Subject: [time-nuts] Thunderbolt and UPS, Was any negatives ? In-Reply-To: References: Message-ID: A slick way of adding a Tbolt monitor and UPS is to use an old laptop that has a CD drive that runs off of a 12V supply. Most CD drives draw a similar amount of power as the Tbolt. Remove the CD drive and power the Tbolt off of the internal laptop power lines (you will also need a +5V and -12V signal which are readily available in the laptop). Voila, battery backed Tbolt with a nice full time interface/status screen. A suitable laptop can be had for around $20. You will probably need to spring another $40 or so for a fresh battery. If your chosen laptop is old and kludgy enough you may even be able to squeeze the Tbolt inside the laptop case where the old drive mounted. The downside of this is the laptop supply may be electrically noisy and inject some noise components into the Tbolt output signal, but then Tom's testing shows every supply does this to varying degrees. _________________________________________________________________ Hotmail? has a new way to see what's up with your friends. http://windowslive.com/Tutorial/Hotmail/WhatsNew?ocid=TXT_TAGLM_WL_HM_Tutorial_WhatsNew1_052009 From hmurray at megapathdsl.net Mon Jun 1 18:36:31 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Mon, 01 Jun 2009 11:36:31 -0700 Subject: [time-nuts] HP/Agilent 5335A In-Reply-To: Message from John Ackermann N8UR of "Mon, 01 Jun 2009 08:32:48 EDT." <4A23CA70.9060703@febo.com> Message-ID: <20090601183632.3DECFBCE9@ip-64-139-1-69.sjc.megapath.net> > Also, don't underestimate the 5334 counters. They are very capable, > though they don't have all the math and statistics functions of the > '35, they are only 1U in height *and have no fan!!!*, and I've bought > several via eBay for $150 or less. Mine are 2U Yes, No fan !! A wonderful starting point if you want to get sucked in. You'll probably want to add on another $150 for the Prologix GPIB-USB gizmo. -- These are my opinions, not necessarily my employer's. I hate spam. From jra at febo.com Mon Jun 1 18:41:21 2009 From: jra at febo.com (John Ackermann N8UR) Date: Mon, 01 Jun 2009 14:41:21 -0400 Subject: [time-nuts] HP/Agilent 5335A In-Reply-To: <20090601183632.3DECFBCE9@ip-64-139-1-69.sjc.megapath.net> References: <20090601183632.3DECFBCE9@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A2420D1.4000200@febo.com> Yeah, I guess they really are 2U, but they're still thinner than the other HP counters. John ---- Hal Murray wrote: >> Also, don't underestimate the 5334 counters. They are very capable, >> though they don't have all the math and statistics functions of the >> '35, they are only 1U in height *and have no fan!!!*, and I've bought >> several via eBay for $150 or less. > > Mine are 2U Yes, No fan !! > > A wonderful starting point if you want to get sucked in. > > You'll probably want to add on another $150 for the Prologix GPIB-USB gizmo. > > From robert8rpi at yahoo.co.uk Mon Jun 1 19:46:00 2009 From: robert8rpi at yahoo.co.uk (Robert Atkinson) Date: Mon, 1 Jun 2009 19:46:00 +0000 (GMT) Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: <406928.3055.qm@web27105.mail.ukl.yahoo.com> Most switch mode power supplies actually run a voltage doubler on the input when running on 110V. This puts over 300V across the transformer and switch. Also the regulation loop crosses the isolation barrier introducing more failure points that can result in overvoltage. Robert G8RPI. --- On Mon, 1/6/09, SAIDJACK at aol.com wrote: > From: SAIDJACK at aol.com > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > To: time-nuts at febo.com > Date: Monday, 1 June, 2009, 6:17 PM > Hi there, > > A switcher has much more stresses on the components, since > it? usually > switches the primary side rectified 110/220V high-voltage > across a? transformer. > Thus the switching FET has to be very high voltage capable > (about? ~170V DC > in the US), and the second? component under stress is > the primary? high > voltage capacitor, because it sees a very fast AC switching > current on it? > (current draw is on when the FET is on, and off when the > Fet is off).? Also > there has to be a fast snubber network to prevent the > back-emf from? destroying > the primary Fet with over-voltage. > > A linear supply has none of these fast current/voltage > transients on it,? > only a couple of diodes switching the 60Hz secondary onto a > capacitor at low? > voltage. > > A secondary concern is thermally induced stress, switchers > will usually be? > packed into a very small enclosure with very high power > capability/density. > This? is not possible for linear supplies, since the > transformer size will > usually? determine overall sizing. Compare a Laptop > power supply size > (usually these have? between 40W and 90W rating!) to a > similar rated linear supply. > > bye, > Said > > > In a message dated 6/1/2009 09:48:29 Pacific Daylight > Time,? > hmurray at megapathdsl.net > writes: > > Is there? something I don't understand in this > area?? What makes a linear? > supply more reliable than a switcher? > > My first guess would be a? switcher would be more > reliable because it would > run cooler. > > That's? probably assuming the same amount of design > effort which is > probably > not a? valid assumption if I'm comparing a brand-X > linear with a brand-Z? > switcher.? A quick glance at the general construction > might give a? better > answer. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From SAIDJACK at aol.com Mon Jun 1 19:52:18 2009 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Mon, 1 Jun 2009 15:52:18 EDT Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: Hi Robert, very good point, one more issue is the number of components used. On switchers, this is easily 10x to 15x the number of components used on a simple linear supply. Every component and it's solder-joints are a statistical sources of failure. bye, Said In a message dated 6/1/2009 12:46:36 Pacific Daylight Time, robert8rpi at yahoo.co.uk writes: Most switch mode power supplies actually run a voltage doubler on the input when running on 110V. This puts over 300V across the transformer and switch. Also the regulation loop crosses the isolation barrier introducing more failure points that can result in overvoltage. Robert G8RPI. From rmoncur at bigpond.net.au Mon Jun 1 21:59:36 2009 From: rmoncur at bigpond.net.au (Rex Moncur) Date: Tue, 2 Jun 2009 07:59:36 +1000 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <406928.3055.qm@web27105.mail.ukl.yahoo.com> Message-ID: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Hi all Does anyone have any experience of locking a USB external soundcard to a GPSDO 10 MHz reference. I am interested in advice on any good quality soundcards that can be readily locked to either 10 MHz or if necessary to some other frequency that we can derive from a GPSDO source. I have done some tests with the SignalLink soundcard that uses a Texas Instruments PCM2904 chip and requires a 12 MHz lock frequency. This requires some cutting of tracks to remove the internal oscillator feedback and insert the locking frequency. 12 MHz is readily derived from 10 MHz but I have not been able to get it to lock. The Texas instruments data sheet suggests that it is possible to use an external refernce but also says this is not recommended. With this expereicne I would rather find a sound card that is designed for external locking that does not require the cutting of tracks. For info the purpose of this request is that we are looking at using very narrow bandwidth modes at less than 1 mHz for light wave communcation. To date using LEDs and cloud reflection we have worked over 200 km with WSJT but we should be able to do 20 dB better if we can get down to milli-Hz bandwidths (at the expense of spending all night to complete a QSO). Our expereince to date is that standard sound cards are just not stable to better than 5 milli-Hz at 1000 Hz which should be readily solved by GPS locking let us get down to sub milli-Hz levels. Rex VK7MO From jpawlan at pawlan.com Mon Jun 1 22:08:24 2009 From: jpawlan at pawlan.com (Jeffrey Pawlan) Date: Mon, 1 Jun 2009 15:08:24 -0700 (PDT) Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: Soundcards for USB are poor at best. I have a set of PCI cards that were previously made by EMU and they accept external reference input. They no longer make the model I have but perhaps they have another PCI card with an external ref input. I am interested in your modulation technique which allows you to use WSJT. Please let me know exactly what you are doing. I also do not know how you are using 5 milliHertz with WSJT since the group of discrete tones occupy more bandwidth. 73, Jeffrey Pawlan WA6KBL From alan.melia at btinternet.com Mon Jun 1 22:29:44 2009 From: alan.melia at btinternet.com (Alan Melia) Date: Mon, 1 Jun 2009 23:29:44 +0100 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: <00c701c9e30b$28787c60$0900a8c0@AM> I have seen it talked about (around the LF fraternity, but generally they are stable enough there and just need calibation) a lot but not accomplished yet. How about injection locking the on board osc....maybe gating the feedback with the reference....note I havent tried this? Another technique I have used to shift "logic-block" oscillators is to vary their supply voltage, they will oscillate from around 3v to well over 5.5v ....that might enable you to phase lock it using a variable regulator to vcxo to crystal?? Alan G3NYK ----- Original Message ----- From: "Rex Moncur" To: "'Discussion of precise time and frequency measurement'" Sent: Monday, June 01, 2009 10:59 PM Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references > > Hi all > > Does anyone have any experience of locking a USB external soundcard to a > GPSDO 10 MHz reference. > > I am interested in advice on any good quality soundcards that can be readily > locked to either 10 MHz or if necessary to some other frequency that we can > derive from a GPSDO source. I have done some tests with the SignalLink > soundcard that uses a Texas Instruments PCM2904 chip and requires a 12 MHz > lock frequency. This requires some cutting of tracks to remove the internal > oscillator feedback and insert the locking frequency. 12 MHz is readily > derived from 10 MHz but I have not been able to get it to lock. The Texas > instruments data sheet suggests that it is possible to use an external > refernce but also says this is not recommended. With this expereicne I > would rather find a sound card that is designed for external locking that > does not require the cutting of tracks. > > For info the purpose of this request is that we are looking at using very > narrow bandwidth modes at less than 1 mHz for light wave communcation. To > date using LEDs and cloud reflection we have worked over 200 km with WSJT > but we should be able to do 20 dB better if we can get down to milli-Hz > bandwidths (at the expense of spending all night to complete a QSO). Our > expereince to date is that standard sound cards are just not stable to > better than 5 milli-Hz at 1000 Hz which should be readily solved by GPS > locking let us get down to sub milli-Hz levels. > > Rex VK7MO > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From rmoncur at bigpond.net.au Mon Jun 1 22:49:26 2009 From: rmoncur at bigpond.net.au (Rex Moncur) Date: Tue, 2 Jun 2009 08:49:26 +1000 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: Message-ID: <20090601224926.GLNU1556.nskntotgx02p.mx.bigpond.com@REX740> Hi Jeff Thanks for your advice which I will follow up - the reason for going for a USB sound card is that the system must be operated portable with a Laptop - but perhaps there is a way to use a PCI sound card on a Laptop. While we use WSJT at present we have a new Mode under development for the mill-Hz bandwidth. In testing this new mode is acheiveing around 15 dB better than WSJT with 5 mHz binwidths and should get to 20 dB better with 1 mHz binwidths. It uses M-ary FSK like WSJT but does not need a reference tone for time or frequency locking on the basis that both soundcards are GPS locked. Timing errors are not an issue as the tone durations are 16 mins at 1 mHz binwidth. We use around 20,000 separate M-ary tones (cf 64 for WSJT), which is sufficient to send the first three characters of a call sign in Clark-Karn source encoded format - thus it requires only two tones to be sent to receve a full callsign. However at one mHz bandwidth this takes 16 minutes to send a single tone and thus an hour to send two callsigns. However, we have some shorter techniques for exchanging reports and RRR so a QSO can be comppleted in around 3 hours, hi. We can fit 20,000 tones spaced 1 mHz apart into just 20 Hz so there is not problem there. We have not yet added FEC which should allow a further improvement but we would like to resolve the sound card stablity issues first. 73 Rex VK7MO From hmurray at megapathdsl.net Mon Jun 1 22:52:48 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Mon, 01 Jun 2009 15:52:48 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: Message from "Rex Moncur" of "Tue, 02 Jun 2009 07:59:36 +1000." <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: <20090601225249.29F00BCE9@ip-64-139-1-69.sjc.megapath.net> rmoncur at bigpond.net.au said: > For info the purpose of this request is that we are looking at using > very narrow bandwidth modes at less than 1 mHz for light wave > communcation. To date using LEDs and cloud reflection we have worked > over 200 km with WSJT but we should be able to do 20 dB better if we > can get down to milli-Hz bandwidths (at the expense of spending all > night to complete a QSO). Our expereince to date is that standard > sound cards are just not stable to better than 5 milli-Hz at 1000 Hz > which should be readily solved by GPS locking let us get down to sub > milli-Hz levels. Sounds like a fun project. Do the clouds shift around enough to cause Doppler problems? You might find something in the way of a DSP or FPGA demo board. (I don't have any suggestions.) Or maybe a demo board for an audio chip. How stable is the osc on your current board? Do you need accuracy or stability? Can you feed a calibration signal in the other stereo channel and sort it out in software? Or tap off some signal in the board and feed that to a counter for calibration. -- These are my opinions, not necessarily my employer's. I hate spam. From jmiles at pop.net Mon Jun 1 22:54:28 2009 From: jmiles at pop.net (John Miles) Date: Mon, 1 Jun 2009 15:54:28 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: Message-ID: The concern I'd have with modifying a USB sound card, or any of them for that matter, is that the glue logic between the ADC and the USB chip may be designed for a certain relationship between the ADC and USB clocks. Running the ADC asynchronously may or may not be robust depending on the assumptions baked into the gate array. It might be OK if your app can tolerate occasional misclocking or dropouts but I'd be reluctant to use a hacked sound card for anything timing-critical. I just (last week) got an AD7760 ADC eval board working with the Digilent Nexys2 FPGA platform, with the EVAL-AD7760 board running from its own 40 MHz clock. It will accept an external 40 MHz clock source that, in turn, wouldn't be hard to derive from 10 MHz. Way overkill for ultra low-bandwidth work, but if anyone is looking for a clean digitizer for audio rates in general, you could do a lot worse than this approach. Cost isn't too bad either, at $130 for the Nexys2 and $150 for the ADC7760 eval board. Of course the big drawback is the lack of any sort of standardized audio driver on the host side. If/when I spin a PCB for this project I'll definitely include a 10 MHz input. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Jeffrey Pawlan > Sent: Monday, June 01, 2009 3:08 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 MHz > references > > > Soundcards for USB are poor at best. > > I have a set of PCI cards that were previously made by EMU and > they accept > external reference input. They no longer make the model I have > but perhaps > they have another PCI card with an external ref input. > > I am interested in your modulation technique which allows you to use WSJT. > Please let me know exactly what you are doing. I also do not know > how you are > using 5 milliHertz with WSJT since the group of discrete tones > occupy more > bandwidth. > From james.p.lux at jpl.nasa.gov Mon Jun 1 23:06:42 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Mon, 1 Jun 2009 16:06:42 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> References: <406928.3055.qm@web27105.mail.ukl.yahoo.com> <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Rex Moncur > Sent: Monday, June 01, 2009 3:00 PM > To: 'Discussion of precise time and frequency measurement' > Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz > references > > > Hi all > > Does anyone have any experience of locking a USB external > soundcard to a GPSDO 10 MHz reference. > > I am interested in advice on any good quality soundcards that > can be readily locked to either 10 MHz or if necessary to > some other frequency that we can derive from a GPSDO source. > I have done some tests with the SignalLink soundcard that > uses a Texas Instruments PCM2904 chip and requires a 12 MHz > lock frequency. This requires some cutting of tracks to > remove the internal oscillator feedback and insert the > locking frequency. 12 MHz is readily derived from 10 MHz but > I have not been able to get it to lock. The Texas > instruments data sheet suggests that it is possible to use an > external refernce but also says this is not recommended. > With this expereicne I would rather find a sound card that is > designed for external locking that does not require the > cutting of tracks. > > For info the purpose of this request is that we are looking > at using very narrow bandwidth modes at less than 1 mHz for > light wave communcation. To date using LEDs and cloud > reflection we have worked over 200 km with WSJT but we should > be able to do 20 dB better if we can get down to milli-Hz > bandwidths (at the expense of spending all night to complete > a QSO). Our expereince to date is that standard sound cards > are just not stable to better than 5 milli-Hz at 1000 Hz > which should be readily solved by GPS locking let us get down > to sub milli-Hz levels. > > Rex VK7MO Some of the "pro" sound interfaces have a "word clock" input. There are a variety of things that take a external input and generate a S/PDIF that's properly timed, as well. Lots of boxes will take a S/PDIF sync input (e.g. the Edirol FA-66 which was used by lots of Flex-Radio folk), so maybe that's something you could easily generate from your 10MHz. A chart at Cakewalk shows that MOTU has a USB interface (828MkII) which has a word clock sync. It's going to be a pricey beast though, with 8in/8out ($800?) Even if you have a word clock input, you're going to have to synthesize that from the 10 MHz. Maybe it's easier to just make a S/PDIF which is a MUCH more common sync signal. ( I think S/PDIF is something like 3 MHz) The HPSDR folks also might have something... From wje at quackers.net Tue Jun 2 01:10:02 2009 From: wje at quackers.net (wje) Date: Mon, 01 Jun 2009 21:10:02 -0400 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <4A247BEA.6090603@quackers.net> Much to my amazement, I did find some notes on the DB-25 15Mhz board pinout: 1 +24V 2 +24V 3 Gnd 4 Gnd 5 6 Freq Adj (this goes directly to the FRS, the board does nothing with it) 7 Gnd 8 -Enable + 9 10 Enable - (notes are unclear on 8, 10, 11, 12. See note below) 11 To 11 on other unit 12 to Fault+ on other unit 13 External 1 (this goes to whatever the dual-osc unit plugs into, function unknown) 14 15 External 2 16 Fault + 17 Fault - 18 Ready + 19 Ready - 20 Gnd 21 Standby + 22 Standby - 23 24 25 Pins with no assignment are not used. Note - as mentioned in the previous post, two units cross-monitor each other. One is selected as primary by a manual switch. The notes I found didn't cover the details, but if I remember correctly, +/- enable selects the primary (one unit is enabled, one disabled). Then, a fault assertion by the primary will cause the secondary to become primary. The secondary's 15Mhz output is disabled; only the primary provides an output. The control lines are all TTL compatible, and are always provided in complimentary pairs. Finally, these pinouts came from tracing a live unit and observing behavior. They might not be completely accurate, but they're close. Bill Ezell ---------- They said 'Windows or better' so I used Linux. GandalfG8 at aol.com wrote: > > In a message dated 01/06/2009 02:23:46 GMT Daylight Time, wje at quackers.net > writes: > > I did at one time have the connector pinout info, but since the board is > fairly useless, I'm not sure I kept it. It does have some nice TNC > connectors and a nice crystal filter, if you happen to need a 15Mhz > filter. > > > > ----------- > Hi Bill > > I did realise, after my posted request, that what was described in the > auction as a 15MHz oscillator was actually a 15MHz filter with 36KHz bandwidth. > Not sure that I need one either:-), but if you do still have the connector > pinout I'd be grateful for a copy. > > regards > > Nigel > GM8PZR > > From danv at olphschool.org Tue Jun 2 01:31:39 2009 From: danv at olphschool.org (Dan Veeneman) Date: Mon, 1 Jun 2009 21:31:39 -0400 Subject: [time-nuts] Problems with TrueTime XL-AK Message-ID: <4e30525a0906011831r1dd9af7fp51e1453f71d3b2b3@mail.gmail.com> Hello, I have a TrueTime XL-AK, model 600-101-036, that appears to have a similar problem to what Tom Van Baak reported with his unit last summer. I set up the unit with the TrueTime antenna and let the unit sit for 24 hours in AUTO mode. It correctly identified my location and switched to TIME mode, however the reported time is not correct (currently showing January 2029). Function 73 is reporting that the GPS is Unlocked and the status LED is red. The unit will keep time if I set it manually, although it still never locks to GPS time. The unit reports "sys ver 29" when starting up, with "V1.046". The unit's serial port output also does not appear to follow the description in the manual (emulation mode is off). Any clues on what I can do to correct the timekeeping and the serial port problems? Perhaps related, is there a firmware upgrade that can be performed? Regards, Dan From sar10538 at gmail.com Tue Jun 2 02:04:10 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Tue, 2 Jun 2009 14:04:10 +1200 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: <20090601164759.0EE94BCE9@ip-64-139-1-69.sjc.megapath.net> References: <1284D7BAD956434C9FA35B20CF5E6778@LapTop> <20090601164759.0EE94BCE9@ip-64-139-1-69.sjc.megapath.net> Message-ID: <1231b6a80906011904h433fc81dw1e9a668137750490@mail.gmail.com> The other issue is noise from a switcher. 2009/6/2 Hal Murray : > > phill.r1 at btinternet.com said: >> I would recommend using a linear PSU, I have some made by a Company >> called ?Lascar (perhaps a different name in the States). These are not >> much larger ?than the Thunderbolt itself with a little more height. >> They have three ?separate VS./Rags, 5 volts and +15/-15 volt supplies >> of sufficient ?capacity - all with trim-pots. Mine has been working >> for at least one year ?non-stop - and you can be confident that it >> will not blown up, unlike some ?switched supplies. > > Is there something I don't understand in this area? ?What makes a linear > supply more reliable than a switcher? > > My first guess would be a switcher would be more reliable because it would > run cooler. > > That's probably assuming the same amount of design effort which is probably > not a valid assumption if I'm comparing a brand-X linear with a brand-Z > switcher. ?A quick glance at the general construction might give a better > answer. > > > > -- > These are my opinions, not necessarily my employer's. ?I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From didier at cox.net Tue Jun 2 02:24:15 2009 From: didier at cox.net (Didier Juges) Date: Mon, 1 Jun 2009 21:24:15 -0500 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: <406928.3055.qm@web27105.mail.ukl.yahoo.com> References: <406928.3055.qm@web27105.mail.ukl.yahoo.com> Message-ID: <0BD06391E6BF4B98B285550DBE416D69@d400> Most likely failures on power supplies are with the power components. Failure of the pass transistor in a linear supply is likely to result in overvoltage at the output, while failure of the switch on a switchmode supply will blow the fuse instantly. It is been my experience (after 30 years in the field) that a properly designed switchmode supply is at least as reliable as a linear supply of the same output power, if for no other reason than the lower dissipation and resulting reduced failure rate. By using integrated controllers with lots of protection features built-in, switchmode supplies tend to be smarter than linear ones, and their failures tend to cause fewer damage to other circuits. Of course, your mileage may vary... Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Atkinson > Sent: Monday, June 01, 2009 2:46 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > > > Most switch mode power supplies actually run a voltage > doubler on the input when running on 110V. This puts over > 300V across the transformer and switch. Also the regulation > loop crosses the isolation barrier introducing more failure > points that can result in overvoltage. > > Robert G8RPI. > > --- On Mon, 1/6/09, SAIDJACK at aol.com wrote: > > > From: SAIDJACK at aol.com > > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > > To: time-nuts at febo.com > > Date: Monday, 1 June, 2009, 6:17 PM > > Hi there, > > > > A switcher has much more stresses on the components, since > it? usually > > switches the primary side rectified 110/220V high-voltage across a? > > transformer. > > Thus the switching FET has to be very high voltage capable (about? > > ~170V DC in the US), and the second? component under stress is the > > primary? high voltage capacitor, because it sees a very fast AC > > switching current on it (current draw is on when the FET is on, and > > off when the Fet is off).? Also there has to be a fast > snubber network > > to prevent the back-emf from? destroying the primary Fet with > > over-voltage. > > > > A linear supply has none of these fast current/voltage > transients on > > it, only a couple of diodes switching the 60Hz secondary onto a > > capacitor at low voltage. > > > > A secondary concern is thermally induced stress, switchers will > > usually be packed into a very small enclosure with very high power > > capability/density. > > This? is not possible for linear supplies, since the > transformer size > > will usually? determine overall sizing. Compare a Laptop > power supply > > size (usually these have? between 40W and 90W rating!) to a similar > > rated linear supply. > > > > bye, > > Said > > > > > > In a message dated 6/1/2009 09:48:29 Pacific Daylight Time, > > hmurray at megapathdsl.net > > writes: > > > > Is there? something I don't understand in this area?? What makes a > > linear supply more reliable than a switcher? > > > > My first guess would be a? switcher would be more reliable > because it > > would run cooler. > > > > That's? probably assuming the same amount of design effort which is > > probably not a? valid assumption if I'm comparing a brand-X linear > > with a brand-Z switcher.? A quick glance at the general > construction > > might give a? better answer. > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, > go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From kilodelta4foxmike at gmail.com Tue Jun 2 03:07:13 2009 From: kilodelta4foxmike at gmail.com (Brian Kirby) Date: Mon, 01 Jun 2009 22:07:13 -0500 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: <4A249761.4060201@gmail.com> I use a Lynx One sound card, it has analog and digital I/O and MIDI I/O and clock I/O. Their manuals are available on line at www.lynxstudio.com. These are profession 24 bit cards, the analog I/O uses balanced interfaces. They handle AES/EBU and SP DIF digital audio formats. The sound card can take an internal clock, an external clock input on the MIDI port, there is a parallel clock header on the PC board, and a digital clock input on the digital audio lines. It can accept a 13.5 Mhz video dot clock, a 27 Mhz video dot clock, and a word clock and word clock/256. It can also take a single source frequency as a referenve clock. Its basicaly set up to sync and slave SMPTE timing systems Hope that helped...... Rex Moncur wrote: > > Hi all > > Does anyone have any experience of locking a USB external soundcard to a > GPSDO 10 MHz reference. > > I am interested in advice on any good quality soundcards that can be readily > locked to either 10 MHz or if necessary to some other frequency that we can > derive from a GPSDO source. I have done some tests with the SignalLink > soundcard that uses a Texas Instruments PCM2904 chip and requires a 12 MHz > lock frequency. This requires some cutting of tracks to remove the internal > oscillator feedback and insert the locking frequency. 12 MHz is readily > derived from 10 MHz but I have not been able to get it to lock. The Texas > instruments data sheet suggests that it is possible to use an external > refernce but also says this is not recommended. With this expereicne I > would rather find a sound card that is designed for external locking that > does not require the cutting of tracks. > > For info the purpose of this request is that we are looking at using very > narrow bandwidth modes at less than 1 mHz for light wave communcation. To > date using LEDs and cloud reflection we have worked over 200 km with WSJT > but we should be able to do 20 dB better if we can get down to milli-Hz > bandwidths (at the expense of spending all night to complete a QSO). Our > expereince to date is that standard sound cards are just not stable to > better than 5 milli-Hz at 1000 Hz which should be readily solved by GPS > locking let us get down to sub milli-Hz levels. > > Rex VK7MO > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From sar10538 at gmail.com Tue Jun 2 05:38:19 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Tue, 2 Jun 2009 17:38:19 +1200 Subject: [time-nuts] Z3805 / MTI 260-0624-C In-Reply-To: <2D17AB46986442B99928FB3242BEADAF@athlon> References: <2D17AB46986442B99928FB3242BEADAF@athlon> Message-ID: <1231b6a80906012238t3b7b955ay21d763c174c67474@mail.gmail.com> Hi Ulrich, I'm in the same boat as you and had no luck finding anything on this unit. I did contact Bob in China (fluke.l) about this and he just sent me the one on the Z3801/16 so no luck there. I can tell you that it does work fine with GPSCon, as demonstrated in the fluke.l's listings. The control ports are RS232, not RS423/4 as stated in the listings. Control is via the bottom port and the upper one is an auxiliary which I have no idea what it does. Also, be aware that the listing also indicates the supply voltage is 40V but my (and the actual one in the listing) should be fed from a lower voltage, I run mine on 24V fine. In fact I bought one of the 40V power supplies from Bob and have ended up running it off the -12V to +12V lines. If you do find any manual for this, please can you forward me a copy or a link. 73, Steve Rooke 2009/6/2 Ulrich Bangert : > Gents, > > I just bought a Z3805 (similar to Z3801/Z3816 but with some differences...) > from Chinese seller fluke.I. > > 1) Has anyone of you a link to a Z3805 manual? The Symmetricon pages have > not. > > 2) This beast is equipped with a MTI 260-0624-C DOCXO. The MTI pages do not > list the option "0624". Has anyone of you an idea what this spec stands for? > > Thanks in advance for your help. > > Ulrich Bangert > www.ulrich-bangert.de > Ortholzer Weg 1 > 27243 Gross Ippener > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From magnus at rubidium.dyndns.org Tue Jun 2 07:43:34 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 02 Jun 2009 09:43:34 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A249761.4060201@gmail.com> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> Message-ID: <4A24D826.1000500@rubidium.dyndns.org> Brian Kirby skrev: > I use a Lynx One sound card, it has analog and digital I/O and MIDI I/O > and clock I/O. Their manuals are available on line at > www.lynxstudio.com. These are profession 24 bit cards, the analog I/O > uses balanced interfaces. They handle AES/EBU and SP DIF digital audio > formats. > > The sound card can take an internal clock, an external clock input on > the MIDI port, there is a parallel clock header on the PC board, and a > digital clock input on the digital audio lines. > > It can accept a 13.5 Mhz video dot clock, a 27 Mhz video dot clock, and > a word clock and word clock/256. 13,5 MHz is ITU-R BT.601/BT.656 luminance sampling rate. 27 MHz is BT.601/BT.656 luminance/chroma-difference combined sampling rate (4:2:2). 27 MHz is the video reference rate of them all. Sad that they broke it when they did the North American HD stuff. Breaking numerology like that isn't very nice... it always cost extra now. I think you mean word-clock * 256 as this is Digidesign/ProTools clock distribution strategy, giving 12,288 MHz for 48 kHz sampling rate. Cheers, Magnus From phill.r1 at btinternet.com Tue Jun 2 09:47:59 2009 From: phill.r1 at btinternet.com (Roy Phillips) Date: Tue, 2 Jun 2009 10:47:59 +0100 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: <0BD06391E6BF4B98B285550DBE416D69@d400> References: <406928.3055.qm@web27105.mail.ukl.yahoo.com> <0BD06391E6BF4B98B285550DBE416D69@d400> Message-ID: <8059904E92D94AF0B27C97E8398BB43D@LapTop> Didier Your comments regarding SMPS are very valid, but there are SMPS designs and then some ! I bought a Wavetek 395 Function Generator with a totally blown up SMPS for approx $100. I attempted to repair this unit but the PCB was badly damaged/burned and one 8-pin Dil device was blown to bits - plus burnt out resistors. I tried to obtain a replacement from the manufacturers without success. After hooking up external supplies and proving that it was otherwise OK, I contemplated building a linear supply within the box - it would have been heavy and difficult to fit. This latter point reinforces your comment about size and power dissipation. The original unit was identical to the average small PC PSU, but with very different outputs. After about 10 months of looking for a solution - I thought I recognized a Wavetek 395 Function Generator in Bob Mokia's Lab. photo, and ask him if he could find me a spare PSU, after a short while he came back with a replacement for around $50 - presto I now have a fully working 395 for $100, which I notice sells for $1500 in the US. Footnote: No axe to grind, but like others in the Group,I have found Bob Mokia to be a "straight" and helpful dealer. Roy ----- Original Message ----- From: "Didier Juges" To: "'Discussion of precise time and frequency measurement'" Sent: Tuesday, June 02, 2009 3:24 AM Subject: Re: [time-nuts] Thunderbolt - any negatives ? Most likely failures on power supplies are with the power components. Failure of the pass transistor in a linear supply is likely to result in overvoltage at the output, while failure of the switch on a switchmode supply will blow the fuse instantly. It is been my experience (after 30 years in the field) that a properly designed switchmode supply is at least as reliable as a linear supply of the same output power, if for no other reason than the lower dissipation and resulting reduced failure rate. By using integrated controllers with lots of protection features built-in, switchmode supplies tend to be smarter than linear ones, and their failures tend to cause fewer damage to other circuits. Of course, your mileage may vary... Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Atkinson > Sent: Monday, June 01, 2009 2:46 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > > > Most switch mode power supplies actually run a voltage > doubler on the input when running on 110V. This puts over > 300V across the transformer and switch. Also the regulation > loop crosses the isolation barrier introducing more failure > points that can result in overvoltage. > > Robert G8RPI. > > --- On Mon, 1/6/09, SAIDJACK at aol.com wrote: > > > From: SAIDJACK at aol.com > > Subject: Re: [time-nuts] Thunderbolt - any negatives ? > > To: time-nuts at febo.com > > Date: Monday, 1 June, 2009, 6:17 PM > > Hi there, > > > > A switcher has much more stresses on the components, since > it usually > > switches the primary side rectified 110/220V high-voltage across a > > transformer. > > Thus the switching FET has to be very high voltage capable (about > > ~170V DC in the US), and the second component under stress is the > > primary high voltage capacitor, because it sees a very fast AC > > switching current on it (current draw is on when the FET is on, and > > off when the Fet is off). Also there has to be a fast > snubber network > > to prevent the back-emf from destroying the primary Fet with > > over-voltage. > > > > A linear supply has none of these fast current/voltage > transients on > > it, only a couple of diodes switching the 60Hz secondary onto a > > capacitor at low voltage. > > > > A secondary concern is thermally induced stress, switchers will > > usually be packed into a very small enclosure with very high power > > capability/density. > > This is not possible for linear supplies, since the > transformer size > > will usually determine overall sizing. Compare a Laptop > power supply > > size (usually these have between 40W and 90W rating!) to a similar > > rated linear supply. > > > > bye, > > Said > > > > > > In a message dated 6/1/2009 09:48:29 Pacific Daylight Time, > > hmurray at megapathdsl.net > > writes: > > > > Is there something I don't understand in this area? What makes a > > linear supply more reliable than a switcher? > > > > My first guess would be a switcher would be more reliable > because it > > would run cooler. > > > > That's probably assuming the same amount of design effort which is > > probably not a valid assumption if I'm comparing a brand-X linear > > with a brand-Z switcher. A quick glance at the general > construction > > might give a better answer. > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, > go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From jdb at lartmaker.nl Tue Jun 2 16:41:27 2009 From: jdb at lartmaker.nl (J.D. Bakker) Date: Tue, 2 Jun 2009 18:41:27 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A24D826.1000500@rubidium.dyndns.org> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> Message-ID: You could always transform this from a hardware problem to a software problem. Take the output of your GPSDO, divide it down to somewhere inside the audio band, feed it to a spare input on your USB sound card and have software track this reference and correct the received signal. JDB. -- LART. 250 MIPS under one Watt. Free hardware design files. http://www.lartmaker.nl/ From magnus at rubidium.dyndns.org Tue Jun 2 17:07:45 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 02 Jun 2009 19:07:45 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: References: <406928.3055.qm@web27105.mail.ukl.yahoo.com> <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: <4A255C61.4030403@rubidium.dyndns.org> Lux, James P skrev: >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Rex Moncur >> Sent: Monday, June 01, 2009 3:00 PM >> To: 'Discussion of precise time and frequency measurement' >> Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz >> references >> >> >> Hi all >> >> Does anyone have any experience of locking a USB external >> soundcard to a GPSDO 10 MHz reference. >> >> I am interested in advice on any good quality soundcards that >> can be readily locked to either 10 MHz or if necessary to >> some other frequency that we can derive from a GPSDO source. >> I have done some tests with the SignalLink soundcard that >> uses a Texas Instruments PCM2904 chip and requires a 12 MHz >> lock frequency. This requires some cutting of tracks to >> remove the internal oscillator feedback and insert the >> locking frequency. 12 MHz is readily derived from 10 MHz but >> I have not been able to get it to lock. The Texas >> instruments data sheet suggests that it is possible to use an >> external refernce but also says this is not recommended. >> With this expereicne I would rather find a sound card that is >> designed for external locking that does not require the >> cutting of tracks. >> >> For info the purpose of this request is that we are looking >> at using very narrow bandwidth modes at less than 1 mHz for >> light wave communcation. To date using LEDs and cloud >> reflection we have worked over 200 km with WSJT but we should >> be able to do 20 dB better if we can get down to milli-Hz >> bandwidths (at the expense of spending all night to complete >> a QSO). Our expereince to date is that standard sound cards >> are just not stable to better than 5 milli-Hz at 1000 Hz >> which should be readily solved by GPS locking let us get down >> to sub milli-Hz levels. >> >> Rex VK7MO > > > Some of the "pro" sound interfaces have a "word clock" input. > > There are a variety of things that take a external input and generate a S/PDIF that's properly timed, as well. Lots of boxes will take a S/PDIF sync input (e.g. the Edirol FA-66 which was used by lots of Flex-Radio folk), so maybe that's something you could easily generate from your 10MHz. > > A chart at Cakewalk shows that MOTU has a USB interface (828MkII) which has a word clock sync. It's going to be a pricey beast though, with 8in/8out ($800?) > > Even if you have a word clock input, you're going to have to > synthesize that from the 10 MHz. Maybe it's easier to just > make a S/PDIF which is a MUCH more common sync signal. ( I > think S/PDIF is something like 3 MHz) S/P-DIF [iec60958-3] has a baudrate which is 128 x sample rate and a bit rate which is 64 x sample rate, which is inherited properties from AES/EBU [aes3] [tech3250] [iec60958-4]. Locking up a S/P-DIF (128 x sample rate) is about the same job as locking up a superclock (256 x sample rate) or wordclock (1 x sample rate). As long as the signal is samples with low jitter and A/D converted in a good fashion, delivery over S/P-DIF should not be too hard. An ADC is slammed onto a AES/EBU/S/P-DIF chip which is fairly trivial extra work. Cheers, Magnus From james.p.lux at jpl.nasa.gov Tue Jun 2 17:47:33 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 2 Jun 2009 10:47:33 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A255C61.4030403@rubidium.dyndns.org> References: <406928.3055.qm@web27105.mail.ukl.yahoo.com> <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A255C61.4030403@rubidium.dyndns.org> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Magnus Danielson > Sent: Tuesday, June 02, 2009 10:08 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 > MHz references > > > > > > > Some of the "pro" sound interfaces have a "word clock" input. > > > > There are a variety of things that take a external input > and generate a S/PDIF that's properly timed, as well. Lots of > boxes will take a S/PDIF sync input (e.g. the Edirol FA-66 > which was used by lots of Flex-Radio folk), so maybe that's > something you could easily generate from your 10MHz. > > > > A chart at Cakewalk shows that MOTU has a USB interface (828MkII) > > which has a word clock sync. It's going to be a pricey > beast though, > > with 8in/8out ($800?) > > > > Even if you have a word clock input, you're going to have to > > synthesize that from the 10 MHz. Maybe it's easier to just make a > > S/PDIF which is a MUCH more common sync signal. ( I think S/PDIF is > > something like 3 MHz) > > S/P-DIF [iec60958-3] has a baudrate which is 128 x sample > rate and a bit rate which is 64 x sample rate, which is > inherited properties from AES/EBU [aes3] [tech3250] [iec60958-4]. > > Locking up a S/P-DIF (128 x sample rate) is about the same > job as locking up a superclock (256 x sample rate) or > wordclock (1 x sample rate). However, if you're buying an off the shelf audio interface, you're stuck with whatever the mfr is providing for a sync input, and a (very) casual inspection of what's available these days (particularly at low cost) shows that S/PDIF seems to be the most common. From dibene at usa.net Tue Jun 2 17:51:27 2009 From: dibene at usa.net (Alberto di Bene) Date: Tue, 02 Jun 2009 19:51:27 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> Message-ID: <4A25669F.9020201@usa.net> J.D. Bakker wrote: > You could always transform this from a hardware problem to a software > problem. Take the output of your GPSDO, divide it down to somewhere > inside the audio band, feed it to a spare input on your USB sound > card and have software track this reference and correct the received > signal. > > JDB. I am in complete agreement with this kind of solution. Sampling on the second channel a reference signal of known value allows the software to make a simple adjustment. No need to switch on the soldering iron... Never do in hardware what can be done in software.... :-) 73 Alberto I2PHD From stanw1le at verizon.net Tue Jun 2 19:01:17 2009 From: stanw1le at verizon.net (Stan W1LE) Date: Tue, 02 Jun 2009 15:01:17 -0400 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A25669F.9020201@usa.net> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> <4A25669F.9020201@usa.net> Message-ID: <4A2576FD.6050705@verizon.net> Hello The Net: For portable operations with a laptop, usually only one input channel is available and it is at mike (not line) level. The alternative to sum the analog reference and the analog signal of interest may be possible if the reference noise can be kept out of the signal of interest bandwidth. Maybe a external USB soundcard with at least 2 input channels is more appropriate. Stan, W1LE FN41sr Cape Cod Alberto di Bene wrote: > J.D. Bakker wrote: >> You could always transform this from a hardware problem to a software >> problem. Take the output of your GPSDO, divide it down to somewhere >> inside the audio band, feed it to a spare input on your USB sound >> card and have software track this reference and correct the received >> signal. >> >> JDB. > > I am in complete agreement with this kind of solution. Sampling on the > second channel a reference signal of known value allows the software > to make a simple adjustment. No need to switch on the soldering iron... > Never do in hardware what can be done in software.... :-) > > 73 Alberto I2PHD From magnus at rubidium.dyndns.org Tue Jun 2 19:24:53 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 02 Jun 2009 21:24:53 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: References: <406928.3055.qm@web27105.mail.ukl.yahoo.com> <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A255C61.4030403@rubidium.dyndns.org> Message-ID: <4A257C85.4040203@rubidium.dyndns.org> Lux, James P skrev: >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Magnus Danielson >> Sent: Tuesday, June 02, 2009 10:08 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 >> MHz references >> >>> >>> Some of the "pro" sound interfaces have a "word clock" input. >>> >>> There are a variety of things that take a external input >> and generate a S/PDIF that's properly timed, as well. Lots of >> boxes will take a S/PDIF sync input (e.g. the Edirol FA-66 >> which was used by lots of Flex-Radio folk), so maybe that's >> something you could easily generate from your 10MHz. >>> A chart at Cakewalk shows that MOTU has a USB interface (828MkII) >>> which has a word clock sync. It's going to be a pricey >> beast though, >>> with 8in/8out ($800?) >>> >>> Even if you have a word clock input, you're going to have to >>> synthesize that from the 10 MHz. Maybe it's easier to just make a >>> S/PDIF which is a MUCH more common sync signal. ( I think S/PDIF is >>> something like 3 MHz) >> S/P-DIF [iec60958-3] has a baudrate which is 128 x sample >> rate and a bit rate which is 64 x sample rate, which is >> inherited properties from AES/EBU [aes3] [tech3250] [iec60958-4]. >> >> Locking up a S/P-DIF (128 x sample rate) is about the same >> job as locking up a superclock (256 x sample rate) or >> wordclock (1 x sample rate). > > However, if you're buying an off the shelf audio interface, you're > stuck with whatever the mfr is providing for a sync input, and a > (very) casual inspection of what's available these days > (particularly at low cost) shows that S/PDIF seems to be the most common. Do they really lock up to the S/P-DIF input? I doubt it for the cheap boards. Rather, they decode the S/P-DIF signal and ship the samples into the DSP. The DSP tends to make very rought sample-rate conversions like dropping samples etc. A lockable board isn't that expensive. You can get them off ebay for instance. Cheers, Magnus From magnus at rubidium.dyndns.org Tue Jun 2 19:31:17 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 02 Jun 2009 21:31:17 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A25669F.9020201@usa.net> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> <4A25669F.9020201@usa.net> Message-ID: <4A257E05.3000108@rubidium.dyndns.org> Alberto di Bene skrev: > J.D. Bakker wrote: >> You could always transform this from a hardware problem to a software >> problem. Take the output of your GPSDO, divide it down to somewhere >> inside the audio band, feed it to a spare input on your USB sound card >> and have software track this reference and correct the received signal. >> >> JDB. > > I am in complete agreement with this kind of solution. Sampling on the > second channel a reference signal of known value allows the software > to make a simple adjustment. Such a double-frequency conversion cancels fairly well the transfer oscillators frequency and jitter, as long as it is sufficienly low. > No need to switch on the soldering iron... > Never do in hardware what can be done in software.... :-) Respectfully I disagree. There are tasks which is better managed by software and tasks which is better managed by hardware. In the world of FPGAs, it is also worth mentioning that some tasks is best done there. The big trick is to find a balance between various methods, available resources, partitioning of the problem, doing it on time and achieving the needed performance. There is an overbeleif in what software is suitable for IMHO. Cheers, Magnus From dibene at usa.net Tue Jun 2 19:51:03 2009 From: dibene at usa.net (Alberto di Bene) Date: Tue, 02 Jun 2009 21:51:03 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A257E05.3000108@rubidium.dyndns.org> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> <4A25669F.9020201@usa.net> <4A257E05.3000108@rubidium.dyndns.org> Message-ID: <4A2582A7.3020806@usa.net> Magnus Danielson wrote: > >> No need to switch on the soldering iron... >> Never do in hardware what can be done in software.... :-) > > Respectfully I disagree. There are tasks which is better managed by > software and tasks which is better managed by hardware. In the world of > FPGAs, it is also worth mentioning that some tasks is best done there. > The big trick is to find a balance between various methods, available > resources, partitioning of the problem, doing it on time and achieving > the needed performance. > Of course you are right, the best solution must be decided case by case. But the biggest plus of the software is that it can be changed on the fly, without an expensive reworking station, and the manual ability to correctly use it. And a side effect is speed : you can test many variants of a solution in a time frame of a few minutes. Not so easily doable with hardware changes. 73 Alberto i2PHD From magnus at rubidium.dyndns.org Tue Jun 2 20:06:23 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 02 Jun 2009 22:06:23 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A2582A7.3020806@usa.net> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> <4A25669F.9020201@usa.net> <4A257E05.3000108@rubidium.dyndns.org> <4A2582A7.3020806@usa.net> Message-ID: <4A25863F.7040603@rubidium.dyndns.org> Alberto di Bene skrev: > Magnus Danielson wrote: >> >>> No need to switch on the soldering iron... >>> Never do in hardware what can be done in software.... :-) >> >> Respectfully I disagree. There are tasks which is better managed by >> software and tasks which is better managed by hardware. In the world >> of FPGAs, it is also worth mentioning that some tasks is best done there. >> The big trick is to find a balance between various methods, available >> resources, partitioning of the problem, doing it on time and achieving >> the needed performance. >> > > Of course you are right, the best solution must be decided case by case. > But the biggest plus of the software is that it can be changed on the fly, > without an expensive reworking station, and the manual ability to correctly > use it. And a side effect is speed : you can test many variants of a > solution > in a time frame of a few minutes. Not so easily doable with hardware > changes. This is why we do alot of things in FPGAs today, and in the FPGAs we often put dedicated DSPs of various complexity, often adapted to their task. Keeping quick turn-around is on our mind, but in general, the shorter turn-around, the poorer testing usually happends, and the sloopier design is often found, and the longer it takes to get the job done. In general, a CPU is suitable for doing non-common tasks. More dedicated designs like firmware and hardware is suitable to do things which is essentially the same but happends over and over and over and often at a high speed. Such monotonic tasks just waste energy, space and complexity when done in CPUs. The problem with a generic CPU is that it is generic, so it can do all kinds of tasks, which makes timing-critical bulk-processing tasks problematic to combine with sporadic and possibly high-dynamic processing. Splice the bulk off to some dedicated processing, which can be done in another CPU, and better performance is yielded. There are loads of designs where a few well thought 8-bit processors work together and shine over a more modern fancy design. One such example is found in the SR-620 which has a Zilog Z-8000 processor as main CPU and a Z-80 co-processor which only does the X-Y vector display. The Z-80 has so small program that it is loaded into SRAM from the Z-8000 as it boots. The HP 5334A has actually 3 different 3870 processor, one for overall control, one for measurements and one for GPIB. Hmm, do you get a feeling that I am actually object very much to just toss it into the processor. I think you are right. :) Nothing wrong with software, but use it wisely. Build the test-benches as if you where doing a ASIC or full-custom design and thus also think about each compile costing you milions of dollars and a pipe-line depth of many months (6-9). I guess I am becomming more conservative by the day. From my own and others mistakes and succsesses. Cheers, Magnus From dibene at usa.net Tue Jun 2 21:50:31 2009 From: dibene at usa.net (Alberto di Bene) Date: Tue, 02 Jun 2009 23:50:31 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A25863F.7040603@rubidium.dyndns.org> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> <4A25669F.9020201@usa.net> <4A257E05.3000108@rubidium.dyndns.org> <4A2582A7.3020806@usa.net> <4A25863F.7040603@rubidium.dyndns.org> Message-ID: <4A259EA7.9080503@usa.net> Magnus Danielson wrote: > > Hmm, do you get a feeling that I am actually object very much to just > toss it into the processor. I think you are right. :) I suppose you are familiar with the old American adage that says that to a man with a hammer every problem looks like a nail.... :-) Each of us is more familiar with one or another technology (broadly speaking), and tend to see it as the best way to solve problems. I am not immune from this... > Nothing wrong with software, but use it wisely. Build the test-benches > as if you where doing a ASIC or full-custom design and thus also think > about each compile costing you milions of dollars and a pipe-line depth > of many months (6-9). Given the rate of compiles that sometimes I do especially when near to find the solution of a problem that bugged me for a long time, I would be bankrupted since long, should each compile cycle cost me thousands or millions of dollars, even if bogus dollars... :-) :-) > I guess I am becomming more conservative by the day. From my own and > others mistakes and succsesses. This is a privilege of becoming older and wiser :-) Cheers, Alberto I2PHD From rmoncur at bigpond.net.au Tue Jun 2 22:06:20 2009 From: rmoncur at bigpond.net.au (Rex Moncur) Date: Wed, 3 Jun 2009 08:06:20 +1000 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: <20090602220621.ZILJ12625.nschwotgx03p.mx.bigpond.com@REX740> Hi all Thank you all for you advice and suggestions re my request. At this stage it does not look like there is a simple solution of a readily available USB sound card that can be locked to a 10 MHz GPSDO reference. The constraints of portable operation with a Laptop rule out a number of solutions. I have tried the software solution using Spectrum Lab but ran into problems and perhaps this just needs more work. One of the main problems is that in working at milli-Hz binwidths the FTT word length needs to be very long to cover even a few tens of Hz range and we run into memory problems. So there is little room to have a reference frequency spaced well away from the frequency range being used. The SP DIF solution seems promising if I can generate the required input. This could perhaps be done with a product that already provides the SP DIF word output and locking that. But that could be just as hard as locking the sound-card in the first place. So at this time I think I will put some more effort into locking the sound card and let you know how I go, hi. Injection locking as suggested by some of you may be the answer. Some people asked for more details of the cloud scatter experiments which area at http://reast.asn.au/optical.php There is also a series of articles on our work in the last 3 and next issue of DUBUS. On the question of Doppler shift from clouds - this is much less than a mHz and not an issue due to the fact that we are using base band and the Doppler only applies to the audio frequency. In addition the very narrow beamwidths (around 2 degrees) mean that the possible paths are all very similar in length. Thanks again to everyone for their input. 73 Rex VK7MO From james.p.lux at jpl.nasa.gov Tue Jun 2 22:18:59 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 2 Jun 2009 15:18:59 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090602220621.ZILJ12625.nschwotgx03p.mx.bigpond.com@REX740> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <20090602220621.ZILJ12625.nschwotgx03p.mx.bigpond.com@REX740> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Rex Moncur > Sent: Tuesday, June 02, 2009 3:06 PM > To: 'Discussion of precise time and frequency measurement' > Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 > MHz references > > Hi all > > Thank you all for you advice and suggestions re my request. > At this stage it does not look like there is a simple > solution of a readily available USB sound card that can be > locked to a 10 MHz GPSDO reference. > > The constraints of portable operation with a Laptop rule out > a number of solutions. I have tried the software solution > using Spectrum Lab but ran into problems and perhaps this > just needs more work. One of the main problems is that in > working at milli-Hz binwidths the FTT word length needs to be > very long to cover even a few tens of Hz range and we run > into memory problems. So there is little room to have a > reference frequency spaced well away from the frequency range > being used. The reference frequency can be right on top of your signal, as long as it's within the dynamic range. You can subtract it out before doing the FFT, after having determined where it is and how big it is. > Some people asked for more details of the cloud scatter > experiments which area at http://reast.asn.au/optical.php > There is also a series of articles on our work in the last 3 > and next issue of DUBUS. > > From connie.marshall at suddenlink.net Wed Jun 3 00:38:25 2009 From: connie.marshall at suddenlink.net (Connie Marshall) Date: Tue, 2 Jun 2009 19:38:25 -0500 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> Message-ID: Hi Rex, Here is a plot of my sound card. Maybe I'm just lucky with this particular sound card/computer, but the drift was only about 250 micro Hertz over a four hour period. Also for critical measurements I try to run at 200 Hz center frequency rather than 1000 Hz. Cuts the error by five. Maybe that's not practical for you modulation schema. I did not bother to calibrate the sound card before I started the test so there is about 550 micro Hertz of static error when the test starts. www.k5cm.com/soundcard.htm 73, Connie K5CM From magnus at rubidium.dyndns.org Wed Jun 3 07:34:42 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 03 Jun 2009 09:34:42 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <4A259EA7.9080503@usa.net> References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <4A249761.4060201@gmail.com> <4A24D826.1000500@rubidium.dyndns.org> <4A25669F.9020201@usa.net> <4A257E05.3000108@rubidium.dyndns.org> <4A2582A7.3020806@usa.net> <4A25863F.7040603@rubidium.dyndns.org> <4A259EA7.9080503@usa.net> Message-ID: <4A262792.1090903@rubidium.dyndns.org> Alberto di Bene skrev: > Magnus Danielson wrote: >> >> Hmm, do you get a feeling that I am actually object very much to just >> toss it into the processor. I think you are right. :) > > I suppose you are familiar with the old American adage that says that to > a man with > a hammer every problem looks like a nail.... :-) Yes. :o) > Each of us is more familiar with one or another technology (broadly > speaking), and tend to see it as the best way to solve problems. I am not immune > from this... This is why I try to find more tools and more approaches. >> Nothing wrong with software, but use it wisely. Build the test-benches >> as if you where doing a ASIC or full-custom design and thus also think >> about each compile costing you milions of dollars and a pipe-line >> depth of many months (6-9). > > Given the rate of compiles that sometimes I do especially when near to > find the solution of a problem that bugged me for a long time, I would be bankrupted > since long, should each compile cycle cost me thousands or millions of > dollars, even if bogus dollars... :-) :-) I think you would learn important lessons in test-benching and overall design before the "compile". >> I guess I am becomming more conservative by the day. From my own and >> others mistakes and succsesses. > > This is a privilege of becoming older and wiser :-) Whiee... I got so much to learn then! :) Cheers, Magnus From magnus at rubidium.dyndns.org Wed Jun 3 07:44:49 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 03 Jun 2009 09:44:49 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: References: <20090601215937.RIWY2116.nskntotgx01p.mx.bigpond.com@REX740> <20090602220621.ZILJ12625.nschwotgx03p.mx.bigpond.com@REX740> Message-ID: <4A2629F1.7010606@rubidium.dyndns.org> Lux, James P skrev: >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Rex Moncur >> Sent: Tuesday, June 02, 2009 3:06 PM >> To: 'Discussion of precise time and frequency measurement' >> Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 >> MHz references >> >> Hi all >> >> Thank you all for you advice and suggestions re my request. >> At this stage it does not look like there is a simple >> solution of a readily available USB sound card that can be >> locked to a 10 MHz GPSDO reference. >> >> The constraints of portable operation with a Laptop rule out >> a number of solutions. I have tried the software solution >> using Spectrum Lab but ran into problems and perhaps this >> just needs more work. One of the main problems is that in >> working at milli-Hz binwidths the FTT word length needs to be >> very long to cover even a few tens of Hz range and we run >> into memory problems. So there is little room to have a >> reference frequency spaced well away from the frequency range >> being used. > > The reference frequency can be right on top of your signal, as long as it's within the dynamic range. You can subtract it out before doing the FFT, after having determined where it is and how big it is. Considering the length of these traces, the local oscillator vs. the reference will shift around. What I would do is to ensure that the reference signal and input signal is either on very different frequencies or different channels. Then, I would in the sampling phase frequency convert the receive signal and reference signal using digital fixed NCO/quadrature oscillators (cos, sin) and do integrate and dump (synchronous dump for both receive and reference signals) processing for low pass filtering and reducing sample rate. Since the signal was fairly narrow banded, this digital receiver approach would significantly reduce the amounts of data while requiring a very reasonable amount of real-time processing. The remaining sample stream still contains the crutial information if sufficient bandwidth is maintained after the integrate and dump processing. Cheers, Magnus From GandalfG8 at aol.com Wed Jun 3 12:11:57 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Wed, 3 Jun 2009 08:11:57 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: In a message dated 02/06/2009 02:11:10 GMT Daylight Time, wje at quackers.net writes: Much to my amazement, I did find some notes on the DB-25 15Mhz board pinout: ------------------- Thanks Bill, that's very much appreciated. As you suggested previously I'm probably not going to find too much use for that board but at least I've now got the information I need to help me decide:-) regards Nigel GM8PZR From martyn at ptsyst.com Wed Jun 3 17:14:49 2009 From: martyn at ptsyst.com (Martyn Smith) Date: Wed, 3 Jun 2009 18:14:49 +0100 Subject: [time-nuts] Any 3048A experts out there?? In-Reply-To: References: Message-ID: Hello, I have a working 3048A phase noise test set. I'm trying to get a new computer to work with the system. I have finally got the computer to talk to the HPIB 82335A HPIB card. I am using windows 98. When I run the PN.exe program, it immediately says that it can't find the HPIB card. However if I run the cal.exe program, that works fine and talks to all my devices. As far as I can see the PN.exe and cal.exe use the same configuration files. Any ideas?? Regards Martyn From hmurray at megapathdsl.net Wed Jun 3 17:23:53 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 03 Jun 2009 10:23:53 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: Message from "Connie Marshall" of "Tue, 02 Jun 2009 19:38:25 CDT." Message-ID: <20090603172354.5BA84BCE9@ip-64-139-1-69.sjc.megapath.net> connie.marshall at suddenlink.net said: > www.k5cm.com/soundcard.htm Nice, thanks. From martyn at ptsyst.com Wed Jun 3 17:56:58 2009 From: martyn at ptsyst.com (Martyn Smith) Date: Wed, 3 Jun 2009 18:56:58 +0100 Subject: [time-nuts] HP3048A Fixed In-Reply-To: References: Message-ID: Hello, Re my email on the 3048A software. I got the unit to work. I have to start windows 98 in dos mode. Don't know why but I'm happy with that. It would be nice to have windows running properly, so if anyone does know the answer, that would be great. Regards Martyn From hmurray at megapathdsl.net Wed Jun 3 17:59:57 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 03 Jun 2009 10:59:57 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: Message from "Rex Moncur" of "Wed, 03 Jun 2009 08:06:20 +1000." <20090602220621.ZILJ12625.nschwotgx03p.mx.bigpond.com@REX740> Message-ID: <20090603175958.B6942BCE9@ip-64-139-1-69.sjc.megapath.net> > One of the main problems is that in working at milli-Hz binwidths the > FTT word length needs to be very long to cover even a few tens of Hz > range and we run into memory problems. I'm missing something. How much memory do you have on your laptop? I'm not a DSP wizard. If you have 10 Hz bandwidth and you want milli-Hz bins, that takes 2x10x1000 samples. Right? I'd expect that to fit easily. That's 20K samples, at 8 bytes each, round up to 10, call it 200K bytes. Jumping to micro-Hz might get interesting. That would be 200 megabytes. Lots of laptops have room for that. Maybe not an old one. Even with an old laptop without much memory, I'd expect you could do several factors of 2 better than milli-Hz bins. On the other hand, how much bandwidth do you really need? Junk crystals are 50-100 ppm. 100 ppm at 1 KHz is 1/10 Hz. So why do you need more than 1 Hz input bandwidth? You can probably get closer than that by calibrating the crystals in your particular gear. Connie's numbers were 250 micro-Hz drift with a 500 micro-Hz offset. (That was with reasonably stable temperature.) So a few milli-Hz bandwidth looks like enough. -- These are my opinions, not necessarily my employer's. I hate spam. From hmurray at megapathdsl.net Wed Jun 3 19:56:01 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 03 Jun 2009 12:56:01 -0700 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: Message from Magnus Danielson of "Tue, 02 Jun 2009 21:31:17 +0200." <4A257E05.3000108@rubidium.dyndns.org> Message-ID: <20090603195602.87B53BCE9@ip-64-139-1-69.sjc.megapath.net> > There is an overbeleif in what software is suitable for IMHO. [Fun discussion. Thanks.] Many years ago, somebody on the FPGA newsgroup pointed out that, in general, if you can do the problem in software that's probably the better way. One of the considerations is that it's easier to hire programmers rather than hardware designers. FPGAs are halfway between real hardware and software. You can try a simple change without any harsh time or cost penalty to make new masks and new chips. If that change is a bug fix, you might think of it as typical sloppy programmer behavior. On the other hand, that change may be a new idea you want to try... For many people in this group, fun is probably the most important consideration. Different things will appeal to different people. -- These are my opinions, not necessarily my employer's. I hate spam. From connie.marshall at suddenlink.net Wed Jun 3 20:40:11 2009 From: connie.marshall at suddenlink.net (Connie Marshall) Date: Wed, 3 Jun 2009 15:40:11 -0500 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090603172354.5BA84BCE9@ip-64-139-1-69.sjc.megapath.net> Message-ID: You know, I probably need to run the test again and do a better job of tracking room temp. My thermometer is high up on the wall in the shack. The computer sets under the bench in a corner. It does represent a typical afternoon in my shack however. 73, Connie K5CM -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Hal Murray Sent: Wednesday, June 03, 2009 12:24 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references connie.marshall at suddenlink.net said: > www.k5cm.com/soundcard.htm Nice, thanks. From jmiles at pop.net Thu Jun 4 00:01:06 2009 From: jmiles at pop.net (John Miles) Date: Wed, 3 Jun 2009 17:01:06 -0700 Subject: [time-nuts] HP3048A Fixed In-Reply-To: Message-ID: > Hello, > > Re my email on the 3048A software. > > I got the unit to work. I have to start windows 98 in dos mode. > > Don't know why but I'm happy with that. > > It would be nice to have windows running properly, so if anyone does know > the answer, that would be great. Have you tried running the non-option 301 software with the TransEra RMB emulator? -- john, KE5FX From df6jb at ulrich-bangert.de Thu Jun 4 06:56:09 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 4 Jun 2009 08:56:09 +0200 Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references In-Reply-To: <20090603175958.B6942BCE9@ip-64-139-1-69.sjc.megapath.net> Message-ID: <0C1C593D4AEE4934AF02524C25DDB8B6@athlon> For a lot of people the FFT seems to be the "one size fits all" solution to any frequency and phase related problem in DSP. It is NOT! For frequency/phase detection & comparisons from sets of sampled data the methods explained in http://ipnpr.jpl.nasa.gov/progress_report/42-121/121G.pdf are MUCH more appropiate. Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Hal Murray > Gesendet: Mittwoch, 3. Juni 2009 20:00 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Sound Cards for locking to GPSDO 10 > MHz references > > > > > One of the main problems is that in working at milli-Hz > binwidths the > > FTT word length needs to be very long to cover even a few > tens of Hz > > range and we run into memory problems. > > I'm missing something. How much memory do you have on your laptop? > > I'm not a DSP wizard. If you have 10 Hz bandwidth and you > want milli-Hz > bins, that takes 2x10x1000 samples. Right? I'd expect that > to fit easily. > > That's 20K samples, at 8 bytes each, round up to 10, call it > 200K bytes. > > Jumping to micro-Hz might get interesting. That would be 200 > megabytes. > Lots of laptops have room for that. Maybe not an old one. > > Even with an old laptop without much memory, I'd expect you > could do several > factors of 2 better than milli-Hz bins. > > On the other hand, how much bandwidth do you really need? > Junk crystals are > 50-100 ppm. 100 ppm at 1 KHz is 1/10 Hz. So why do you need > more than 1 Hz > input bandwidth? You can probably get closer than that by > calibrating the > crystals in your particular gear. > > Connie's numbers were 250 micro-Hz drift with a 500 micro-Hz > offset. (That > was with reasonably stable temperature.) So a few milli-Hz > bandwidth looks > like enough. > > > > > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From sar10538 at gmail.com Fri Jun 5 10:49:57 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Fri, 5 Jun 2009 22:49:57 +1200 Subject: [time-nuts] Request for manuals for HP 5372A Message-ID: <1231b6a80906050349h6a5234aap359128f76443f167@mail.gmail.com> Does anyone have any links to the documentation for the HP 5372A please? I have the programming manual from the Agilent site but the is no Ops/Service manuals and I'm sure there must be tons of stuff for this very versatile instrument. Thanks & 73, Steve -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From GandalfG8 at aol.com Fri Jun 5 11:54:59 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Fri, 5 Jun 2009 07:54:59 EDT Subject: [time-nuts] Request for manuals for HP 5372A Message-ID: In a message dated 05/06/2009 11:50:58 GMT Daylight Time, sar10538 at gmail.com writes: Does anyone have any links to the documentation for the HP 5372A please? I have the programming manual from the Agilent site but the is no Ops/Service manuals and I'm sure there must be tons of stuff for this very versatile instrument. Thanks & 73, Steve ---------- They're all on the Agilent web site....... _http://www.home.agilent.com/_ (http://www.home.agilent.com/) Just enter 5372A in the search box and select "Electronic Test and Measurement" in the drop down box next to that. regards Nigel GM8PZR From frledda at verizon.net Fri Jun 5 12:16:24 2009 From: frledda at verizon.net (Francesco Ledda) Date: Fri, 05 Jun 2009 07:16:24 -0500 Subject: [time-nuts] Request for manuals for HP 5372A In-Reply-To: Message-ID: try http://www.mkdw.net/pub/radio/hp/Manuals/?C=N;O=D The manual is 05372-90016.pdf -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of GandalfG8 at aol.com Sent: Friday, June 05, 2009 6:55 AM To: time-nuts at febo.com Subject: Re: [time-nuts] Request for manuals for HP 5372A In a message dated 05/06/2009 11:50:58 GMT Daylight Time, sar10538 at gmail.com writes: Does anyone have any links to the documentation for the HP 5372A please? I have the programming manual from the Agilent site but the is no Ops/Service manuals and I'm sure there must be tons of stuff for this very versatile instrument. Thanks & 73, Steve ---------- They're all on the Agilent web site....... _http://www.home.agilent.com/_ (http://www.home.agilent.com/) Just enter 5372A in the search box and select "Electronic Test and Measurement" in the drop down box next to that. regards Nigel GM8PZR _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From aceamusements at mchsi.com Fri Jun 5 14:57:09 2009 From: aceamusements at mchsi.com (aceamusements at mchsi.com) Date: Fri, 05 Jun 2009 14:57:09 +0000 Subject: [time-nuts] Request for manuals for HP 5372A In-Reply-To: Message-ID: <060520091457.29307.4A2932450009CF780000727B223245003003010CD2079C080C03BF9C9B020A030A9C9A030E0A0C0E@mchsi.com> Hi, I also have several of these but none have the 2 ghz option C installed I was wondering if anybody out there would happen to have any option C avail or a unit for parts with option C? or possibly know where one could purchase the card and input plug without buying another complete unit?? -------------- Original message from GandalfG8 at aol.com: -------------- > In a message dated 05/06/2009 11:50:58 GMT Daylight Time, > sar10538 at gmail.com writes: > Does anyone have any links to the documentation for the HP 5372A > please? I have the programming manual from the Agilent site but the is > no Ops/Service manuals and I'm sure there must be tons of stuff for > this very versatile instrument. > > Thanks & 73, > Steve > ---------- > They're all on the Agilent web site....... > > _http://www.home.agilent.com/_ (http://www.home.agilent.com/) > > Just enter 5372A in the search box and select "Electronic Test and > Measurement" in the drop down box next to that. > > regards > > Nigel > GM8PZR > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From frledda at verizon.net Fri Jun 5 15:34:26 2009 From: frledda at verizon.net (Francesco Ledda) Date: Fri, 05 Jun 2009 10:34:26 -0500 Subject: [time-nuts] Request for manuals for HP 5372A In-Reply-To: <060520091457.29307.4A2932450009CF780000727B223245003003010CD2079C080C03BF9C9B020A030A9C9A030E0A0C0E@mchsi.com> Message-ID: I used the 5372 for years to design and test SONET synchronizers. I had option 40 istalled but never used it. I always downconverted my test clock to 1 kHz or lower to increase the resolution of the counter. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of aceamusements at mchsi.com Sent: Friday, June 05, 2009 9:57 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Request for manuals for HP 5372A Hi, I also have several of these but none have the 2 ghz option C installed I was wondering if anybody out there would happen to have any option C avail or a unit for parts with option C? or possibly know where one could purchase the card and input plug without buying another complete unit?? -------------- Original message from GandalfG8 at aol.com: -------------- > In a message dated 05/06/2009 11:50:58 GMT Daylight Time, > sar10538 at gmail.com writes: > Does anyone have any links to the documentation for the HP 5372A > please? I have the programming manual from the Agilent site but the is > no Ops/Service manuals and I'm sure there must be tons of stuff for > this very versatile instrument. > > Thanks & 73, > Steve > ---------- > They're all on the Agilent web site....... > > _http://www.home.agilent.com/_ (http://www.home.agilent.com/) > > Just enter 5372A in the search box and select "Electronic Test and > Measurement" in the drop down box next to that. > > regards > > Nigel > GM8PZR > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From sar10538 at gmail.com Fri Jun 5 17:25:43 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Sat, 6 Jun 2009 05:25:43 +1200 Subject: [time-nuts] Request for manuals for HP 5372A In-Reply-To: References: Message-ID: <1231b6a80906051025o1d862fe9y5433709f136b30a5@mail.gmail.com> Thanks Nigel. I seemed to miss this and ended up at a different Agilent site. 2009/6/5 : > In a message dated 05/06/2009 11:50:58 GMT Daylight Time, > sar10538 at gmail.com writes: > Does anyone have any links to the documentation ?for the HP 5372A > please? I have the programming manual from the Agilent site ?but the is > no Ops/Service manuals and I'm sure there must be tons of stuff ?for > this very versatile instrument. > > Thanks & ?73, > Steve > ---------- > They're all on the Agilent web ?site....... > > _http://www.home.agilent.com/_ (http://www.home.agilent.com/) > > Just enter 5372A in the search box and select "Electronic Test and > Measurement" in the drop down box next to that. > > regards > > Nigel > GM8PZR > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From sar10538 at gmail.com Fri Jun 5 17:27:38 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Sat, 6 Jun 2009 05:27:38 +1200 Subject: [time-nuts] Request for manuals for HP 5372A In-Reply-To: References: Message-ID: <1231b6a80906051027rf2ef1d7mf86eb6ab16f2a57a@mail.gmail.com> Thanks Francesco. 2009/6/6 Francesco Ledda : > try > > http://www.mkdw.net/pub/radio/hp/Manuals/?C=N;O=D > > The manual is 05372-90016.pdf > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of GandalfG8 at aol.com > Sent: Friday, June 05, 2009 6:55 AM > To: time-nuts at febo.com > Subject: Re: [time-nuts] Request for manuals for HP 5372A > > > In a message dated 05/06/2009 11:50:58 GMT Daylight Time, > sar10538 at gmail.com writes: > Does anyone have any links to the documentation ?for the HP 5372A > please? I have the programming manual from the Agilent site ?but the is > no Ops/Service manuals and I'm sure there must be tons of stuff ?for > this very versatile instrument. > > Thanks & ?73, > Steve > ---------- > They're all on the Agilent web ?site....... > > _http://www.home.agilent.com/_ (http://www.home.agilent.com/) > > Just enter 5372A in the search box and select "Electronic Test and > Measurement" in the drop down box next to that. > > regards > > Nigel > GM8PZR > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From yuri at ostry.ru Fri Jun 5 21:49:41 2009 From: yuri at ostry.ru (Yuri Ostry) Date: Sat, 6 Jun 2009 01:49:41 +0400 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <198973901.20090606014941@ostry.ru> Hello, Sunday, May 31, 2009, 19:29:23, GandalfG8 wrote: G> Bob, Fluke.1, is selling these on Ebay, for example item # 290313671907, G> and supplies the FRS module itself with an interface board containing the G> FRS connector, plus another PCB containing a 15MHz oscillator and assorted G> other parts that the FRS interface board plugs into. G> Connecting up the FRS itself via the 10 way header on the interface board G> is simple enough, most connections are marked and others easily traced, but G> there's no information available regarding the other PCB. By the way, I still think about building something more useful to be put to the same place in that nice metal box. For example PIC with serial interface to the outside world and fine tuning DAC to adjust Rb source, plus cleanup PLL loop with TCXO, plus some divider to 2 or 4 isolated outputs... Maybe same PIC for monitoring everything inside, from temperatures and voltages to Rb unit health status (lamp voltage, lock status, etc)... If enough people have such units, it may become group project... -- Best regards, Yuri mailto:yuri at ostry.ru From GandalfG8 at aol.com Fri Jun 5 21:56:31 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Fri, 5 Jun 2009 17:56:31 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: In a message dated 05/06/2009 22:50:44 GMT Daylight Time, yuri at ostry.ru writes: By the way, I still think about building something more useful to be put to the same place in that nice metal box. For example PIC with serial interface to the outside world and fine tuning DAC to adjust Rb source, plus cleanup PLL loop with TCXO, plus some divider to 2 or 4 isolated outputs... Maybe same PIC for monitoring everything inside, from temperatures and voltages to Rb unit health status (lamp voltage, lock status, etc)... If enough people have such units, it may become group project... --------------------- Hi Yuri That's an interesting thought but those that Bob is supplying are offered without the metal box. He does have them available but estimates the weight at 5Kg which, for me anyway, would have put too much on the delivery cost. regards Nigel GM8PZR From yuri at ostry.ru Sat Jun 6 07:00:16 2009 From: yuri at ostry.ru (Yuri Ostry) Date: Sat, 6 Jun 2009 11:00:16 +0400 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <599768938.20090606110016@ostry.ru> Hello, Saturday, June 6, 2009, 1:56:31, GandalfG8 wrote: G> That's an interesting thought but those that Bob is supplying are offered G> without the metal box. G> He does have them available but estimates the weight at 5Kg which, for me G> anyway, would have put too much on the delivery cost. I mean only nice inner small box, that is made of galvanized sheet steel (and provide additional magnetic shielding for rb source, as I think). It is easily detachable from large outer case and heatsink, and will not add that much to weight or volume weight. You can put it on another heatsink pretty easily (but I decided to keep whole casing). -- Best regards, Yuri mailto:yuri at ostry.ru -------------- next part -------------- A non-text attachment was scrubbed... Name: rb.jpg Type: image/jpeg Size: 43915 bytes Desc: not available URL: From GandalfG8 at aol.com Sat Jun 6 11:43:34 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sat, 6 Jun 2009 07:43:34 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: In a message dated 06/06/2009 08:01:29 GMT Daylight Time, yuri at ostry.ru writes: I mean only nice inner small box, that is made of galvanized sheet steel (and provide additional magnetic shielding for rb source, as I think). It is easily detachable from large outer case and heatsink, and will not add that much to weight or volume weight. You can put it on another heatsink pretty easily (but I decided to keep whole casing). ----------- Hi Yuri I see now what you mean, but we have different units. If you take a look at Ebay item 290313671907, you'll see that what I was referring to comes as the rubidium module plus two interlocking PCBs but no metalwork. regards Nigel GM8PZR From yuri at ostry.ru Sat Jun 6 12:52:15 2009 From: yuri at ostry.ru (Yuri Ostry) Date: Sat, 6 Jun 2009 16:52:15 +0400 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <97637336.20090606165215@ostry.ru> Hello, Saturday, June 6, 2009, 15:43:34, GandalfG8 wrote: G> I see now what you mean, but we have different units. G> If you take a look at Ebay item 290313671907, you'll see that what I was G> referring to comes as the rubidium module plus two interlocking PCBs but no G> metalwork. It is the same unit, without casing. Looks attached photo for details. By the way, does anyone know model of MMIC amplifier (gold plated one) on that PCB? -- Best regards, Yuri mailto:yuri at ostry.ru -------------- next part -------------- A non-text attachment was scrubbed... Name: rb2.jpg Type: image/jpeg Size: 50989 bytes Desc: not available URL: From yuri at ostry.ru Sat Jun 6 12:57:44 2009 From: yuri at ostry.ru (Yuri Ostry) Date: Sat, 6 Jun 2009 16:57:44 +0400 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <139836759.20090606165744@ostry.ru> Hello, Saturday, June 6, 2009, 15:43:34, GandalfG8. wrote: G> I see now what you mean, but we have different units. G> If you take a look at Ebay item 290313671907, you'll see that what I was G> referring to comes as the rubidium module plus two interlocking PCBs but no G> metalwork. Oops, sorry... Wrong image was attached to previous posting. Here is correct picture. -- Best regards, Yuri mailto:yuri at ostry.ru -------------- next part -------------- A non-text attachment was scrubbed... Name: rb3.jpg Type: image/jpeg Size: 47294 bytes Desc: not available URL: From GandalfG8 at aol.com Sat Jun 6 13:16:27 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sat, 6 Jun 2009 09:16:27 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: In a message dated 06/06/2009 13:58:43 GMT Daylight Time, yuri at ostry.ru writes: Oops, sorry... Wrong image was attached to previous posting. Here is correct picture. ---------- OK, so at last I understand:-) I thought your earlier picture with the flexible connector was showing the back of the rubidium module itself and didn't realise it was a separate case. Unfortunately I have none of that metalwork, just the rubidium module and the two PCBs. regards Nigel GM8PZR From richiem at hughes.net Sat Jun 6 17:29:15 2009 From: richiem at hughes.net (Dick Moore) Date: Sat, 6 Jun 2009 10:29:15 -0700 Subject: [time-nuts] Need volt-nuts help In-Reply-To: References: Message-ID: <78F5CDBE-F9DA-40BC-B277-9E5FCA95DB67@hughes.net> You all are an amazing resource, so even if this is not time-nuts material, someone of you may be able to shed some light. I picked up a differential voltmeter made by Precision Measurements Corp. It says it's brand is CSC (no info on what this stands for), model DC 200C. In general, it is similar to a Fluke 885 but with a much more readable meter, larger easier to use knobs, and overall fewer parts; plus a lot more empty space. The null detector/voltmeter section is not working, but the power supply and K-V divider are fine, as are all the switches. I've checked various sites for manuals with no luck, and also Googled and found nothing. Rather than try now to reverse engineer the schematic, I'm hoping one of you may know something about this machine. If nothing else it will be an interesting platform for play. Thx, Dick Moore From ed_palmer at sasktel.net Sat Jun 6 23:11:30 2009 From: ed_palmer at sasktel.net (Ed Palmer) Date: Sat, 06 Jun 2009 17:11:30 -0600 Subject: [time-nuts] Need volt-nuts help In-Reply-To: <78F5CDBE-F9DA-40BC-B277-9E5FCA95DB67@hughes.net> References: <78F5CDBE-F9DA-40BC-B277-9E5FCA95DB67@hughes.net> Message-ID: <4A2AF7A2.7010809@sasktel.net> Sounds similar to one that I've got. CSC stands for "Calibration Standards Corporation". Mine is DC-110B, but it looks identical to: http://cgi.ebay.ca/Precision-DC-Null-Voltmeter-DC-150B_W0QQitemZ290321205779 . I've seen an identical unit under the Honeywell brand. There are manuals on *Bay for similar units. Search for "calibration standards" voltmeter I'd guess that the meter section is similar in all of them. I don't have a manual for mine, unfortunately. Ed Dick Moore wrote: > You all are an amazing resource, so even if this is not time-nuts > material, someone of you may be able to shed some light. > > I picked up a differential voltmeter made by Precision Measurements > Corp. It says it's brand is CSC (no info on what this stands for), > model DC 200C. In general, it is similar to a Fluke 885 but with a > much more readable meter, larger easier to use knobs, and overall > fewer parts; plus a lot more empty space. The null detector/voltmeter > section is not working, but the power supply and K-V divider are fine, > as are all the switches. > > I've checked various sites for manuals with no luck, and also Googled > and found nothing. Rather than try now to reverse engineer the > schematic, I'm hoping one of you may know something about this > machine. If nothing else it will be an interesting platform for play. > > Thx, > Dick Moore > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From jgd at johngsbbq.com Sat Jun 6 23:54:17 2009 From: jgd at johngsbbq.com (neon John) Date: Sat, 06 Jun 2009 19:54:17 -0400 Subject: [time-nuts] OT: Timer-counter wanted Message-ID: <4A2B01A9.3040308@johngsbbq.com> Hey guys, I'm looking for a counter/timer for my lab. I don't need anything of Time Nuts grade, just a general purpose counter. I don't do sleazebay plus I'd rather pass a few bux to a fellow time nutter. So if you have a spare one of fairly recent vintage, preferably not containing a cooling fan, drop me a note. Please reply off-list: jgd at neon-john.com Thanks John -- John DeArmond Tellico Plains, Occupied TN http://www.neon-john.com <-- email from here http://www.johndearmond.com <-- Best damned Blog on the net PGP key: wwwkeys.pgp.net: BCB68D77 From lstoskopf at cox.net Sun Jun 7 03:20:22 2009 From: lstoskopf at cox.net (lstoskopf at cox.net) Date: Sat, 6 Jun 2009 23:20:22 -0400 Subject: [time-nuts] Re :rubidium osc box In-Reply-To: Message-ID: <20090606232022.M9RFI.220465.imail@eastrmwml46> If you want to go totally crazy on a shielded box, check out Electronic Goldmine's MU metal sticky shielding. Used to be used on CRT shields, etc. Probably not needed, but should kill a bunch of LF noise. Make a sandwich over the wires entering the box, etc. N0UU From wje at quackers.net Sun Jun 7 16:06:02 2009 From: wje at quackers.net (wje) Date: Sun, 07 Jun 2009 12:06:02 -0400 Subject: [time-nuts] 4 channel 1 Mhz - 25 Mhz distribution amp Message-ID: <4A2BE56A.3070005@quackers.net> I finally gave up trying to find a 50 ohm distribution amp I liked and wanted to pay for, so I built a simple 4 channel one that uses either a Linear LT1365 or an Analog Devices AD8044. It has an ac-coupled input and transformer-isolated outputs. I took care in the layout to keep trace lengths exactly the same for all channels, and they're also striplines. (not that using striplines makes much difference with 0.5" trace lengths). Warning - it doesn't have perfect unity gain, 0 chan-chan phase error, infinitely low noise, infiinte isolation, or any of those other characteristics Time-Nuts expect. What it does to (using the LT1365 @ 10Mhz) is accept a 10dBm input, provide 50dB worst-case channel-channel isolation, 68 dB worst-case output-input reverse isolation, and worst-case 0.2 degree channel-channel phase error. I'm not quite sure about the noise; it's down around the noise level of my HP 3588A, which reports -139dBm/rtHz for the amp. This is also the basic noise figure of the 3588, so the amp is probably lower. The amp specs say 9nV/rtHz, which works out to -147dBm referred to 50 ohms, assuming I did my quick calculations correctly. Interestingly, the phase error between 3 of the 4 channels is down around 0.02 degrees; just one channel has the 0.2 degree error relative to all the others. This was measured with my HP 5370 using 10k samples per reading. The LT1365 datasheet says 0.04 max. Hmm.. maybe I should check the coax for that channel. The gain is less than unity at all frequencies. Why? Because I wanted to be able to accept a 10dBm input without clipping and still get close to that out. Using the LT1365, this is possible. The AD8044 will start clipping at about 6dBm because it doesn't have enough current drive. However, it has a MUCH flatter bandwidth curve, managing 0.2 dB from <1Mhz to >50Mhz. The LT1365 is significantly worse, but for a single-frequency distribution amp, this isn't all that important. Using the LT1365, the gain is -1.5 dB @ 10 Mhz, -0.9 @ 5Mhz. Of course, you can trim the gain for whatever you want within the voltage and current limits of the op amp. The opamp is set for a gain of 2 by default (to drive the series-terminated output transformer). If anyone is interested, I can put the schematic, pc board layout, and various plots from my 3588 for the amp on my FTP site. -- Bill Ezell ---------- They said 'Windows or better' so I used Linux. From garnere at gmail.com Sun Jun 7 16:12:56 2009 From: garnere at gmail.com (Eric Garner) Date: Sun, 7 Jun 2009 09:12:56 -0700 Subject: [time-nuts] 4 channel 1 Mhz - 25 Mhz distribution amp In-Reply-To: <4A2BE56A.3070005@quackers.net> References: <4A2BE56A.3070005@quackers.net> Message-ID: I've been thinking about building something like this for some time and I would be interested in seeing the schematics & layout. please do post them! thanks -eric On Sun, Jun 7, 2009 at 9:06 AM, wje wrote: > I finally gave up trying to find a 50 ohm distribution amp I liked and > wanted to pay for, so I built a simple 4 channel one that uses either a > Linear LT1365 or an Analog Devices AD8044. It has an ac-coupled input and > transformer-isolated outputs. I took care in the layout to keep trace > lengths exactly the same for all channels, and they're also striplines. (not > that using striplines makes much difference with 0.5" trace lengths). > > Warning - it doesn't have perfect unity gain, 0 chan-chan phase error, > infinitely low noise, infiinte isolation, or any of those other > characteristics Time-Nuts expect. > > What it does to (using the LT1365 @ 10Mhz) is accept a 10dBm input, provide > 50dB worst-case channel-channel isolation, 68 dB worst-case output-input > reverse isolation, and worst-case 0.2 degree channel-channel phase error. > I'm not quite sure about the noise; it's down around the noise level of my > HP 3588A, which reports -139dBm/rtHz for the amp. This is also the basic > noise figure of the 3588, so the amp is probably lower. The amp specs say > 9nV/rtHz, which works out to -147dBm referred to 50 ohms, assuming I did my > quick calculations correctly. > > Interestingly, the phase error between 3 of the 4 channels is down around > 0.02 degrees; just one channel has the 0.2 degree error relative to all the > others. This was measured with my HP 5370 using 10k samples per reading. The > LT1365 datasheet says 0.04 max. Hmm.. maybe I should check the coax for that > channel. > > The gain is less than unity at all frequencies. Why? Because I wanted to be > able to accept a 10dBm input without clipping and still get close to that > out. Using the LT1365, this is possible. The AD8044 will start clipping at > about 6dBm because it doesn't have enough current drive. However, it has a > MUCH flatter bandwidth curve, managing 0.2 dB from <1Mhz to >50Mhz. The > LT1365 is significantly worse, but for a single-frequency distribution amp, > this isn't all that important. Using the LT1365, the gain is -1.5 dB @ 10 > Mhz, -0.9 @ 5Mhz. Of course, you can trim the gain for whatever you want > within the voltage and current limits of the op amp. The opamp is set for a > gain of 2 by default (to drive the series-terminated output transformer). > > If anyone is interested, I can put the schematic, pc board layout, and > various plots from my 3588 for the amp on my FTP site. > > -- > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- --Eric _________________________________________ Eric Garner From kyrrin at bluefeathertech.com Sun Jun 7 16:14:48 2009 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Sun, 07 Jun 2009 09:14:48 -0700 Subject: [time-nuts] 4 channel 1 Mhz - 25 Mhz distribution amp In-Reply-To: <4A2BE56A.3070005@quackers.net> References: <4A2BE56A.3070005@quackers.net> Message-ID: <200906070914480025.02A3CBC8@192.168.42.129> Hi, Bill, I would be at least curious about the beastie. Please do post what you have. Thanks. *********** REPLY SEPARATOR *********** On 07-Jun-09 at 12:06 wje wrote: >I finally gave up trying to find a 50 ohm distribution amp I liked and >wanted to pay for, so I built a simple 4 channel one that uses either a >Linear LT1365 or an Analog Devices AD8044. It has an ac-coupled input >and transformer-isolated outputs. I took care in the layout to keep >trace lengths exactly the same for all channels, and they're also >striplines. (not that using striplines makes much difference with 0.5" >trace lengths). > >Warning - it doesn't have perfect unity gain, 0 chan-chan phase error, >infinitely low noise, infiinte isolation, or any of those other >characteristics Time-Nuts expect. > >What it does to (using the LT1365 @ 10Mhz) is accept a 10dBm input, >provide 50dB worst-case channel-channel isolation, 68 dB worst-case >output-input reverse isolation, and worst-case 0.2 degree >channel-channel phase error. I'm not quite sure about the noise; it's >down around the noise level of my HP 3588A, which reports -139dBm/rtHz >for the amp. This is also the basic noise figure of the 3588, so the amp >is probably lower. The amp specs say 9nV/rtHz, which works out to >-147dBm referred to 50 ohms, assuming I did my quick calculations >correctly. > >Interestingly, the phase error between 3 of the 4 channels is down >around 0.02 degrees; just one channel has the 0.2 degree error relative >to all the others. This was measured with my HP 5370 using 10k samples >per reading. The LT1365 datasheet says 0.04 max. Hmm.. maybe I should >check the coax for that channel. > >The gain is less than unity at all frequencies. Why? Because I wanted to >be able to accept a 10dBm input without clipping and still get close to >that out. Using the LT1365, this is possible. The AD8044 will start >clipping at about 6dBm because it doesn't have enough current drive. >However, it has a MUCH flatter bandwidth curve, managing 0.2 dB from ><1Mhz to >50Mhz. The LT1365 is significantly worse, but for a >single-frequency distribution amp, this isn't all that important. Using >the LT1365, the gain is -1.5 dB @ 10 Mhz, -0.9 @ 5Mhz. Of course, you >can trim the gain for whatever you want within the voltage and current >limits of the op amp. The opamp is set for a gain of 2 by default (to >drive the series-terminated output transformer). > >If anyone is interested, I can put the schematic, pc board layout, and >various plots from my 3588 for the amp on my FTP site. > >-- >Bill Ezell >---------- >They said 'Windows or better' >so I used Linux. > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > >__________ Information from ESET Smart Security, version of virus >signature database 4136 (20090606) __________ > >The message was checked by ESET Smart Security. > >http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "Quid Malmborg in Plano..." From masondg44 at comcast.net Sun Jun 7 17:16:30 2009 From: masondg44 at comcast.net (Dave M) Date: Sun, 7 Jun 2009 13:16:30 -0400 Subject: [time-nuts] Need volt-nuts help Message-ID: <0DE688B8E0B245DFA15563DF9583024B@D77M7BF1> Dick, The Manuals Plus website lists several manuals for the CSC model DC200B/BR. Don't know what the differences are between the -B/BR models and the -C model, but sometimes the differences can be small; perhaps small enough for you to diagnose your problem. Go to http://www.manualsplus.com/catalog/mp_find.php and search for model DC200 and you'll see the listing. I used to work in a cal/repair lab, and saw many Fluke differential meters over the years. Aside from cleanliness problems, the most prevalent defect that I saw was the chopper in the error amp circuit. The early Flukes used a mechanical chopper, and had a limited lifetime. The later models used electro-optical choppers, eventually moving to FETs. Don't know what type of stabilization your instrument uses, but I recommend that to be the first thing you should check. Geed luck with your instrument. Dave M masondg44 at comcast dot net One good thing about Alzheimer's; you get to meet new people every day. > Date: Sat, 6 Jun 2009 10:29:15 -0700 > From: Dick Moore > Subject: [time-nuts] Need volt-nuts help > To: time-nuts at febo.com > > You all are an amazing resource, so even if this is not time-nuts > material, someone of you may be able to shed some light. > > I picked up a differential voltmeter made by Precision Measurements > Corp. It says it's brand is CSC (no info on what this stands for), > model DC 200C. In general, it is similar to a Fluke 885 but with a > much more readable meter, larger easier to use knobs, and overall > fewer parts; plus a lot more empty space. The null detector/voltmeter > section is not working, but the power supply and K-V divider are fine, > as are all the switches. > > I've checked various sites for manuals with no luck, and also Googled > and found nothing. Rather than try now to reverse engineer the > schematic, I'm hoping one of you may know something about this > machine. If nothing else it will be an interesting platform for play. > > Thx, > Dick Moore From wje at quackers.net Mon Jun 8 01:28:33 2009 From: wje at quackers.net (wje) Date: Sun, 07 Jun 2009 21:28:33 -0400 Subject: [time-nuts] Distribution amp Message-ID: <4A2C6941.1030609@quackers.net> Per request, I've put the info up on my ftp site: ftp://ftp at quackers.net:ftp at ftp.quackers.net/ Pick up DistAmp.zip. Also, read the ReadMe! It explains how to actually look at the board layout. I'm using it to distribute my 10 Mhz GPS-based standard (Thunderbolt) to my spectrum analyzer, counter, and synthesizer, with one left over. -- Bill Ezell ---------- They said 'Windows or better' so I used Linux. From bruce.griffiths at xtra.co.nz Mon Jun 8 01:51:13 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Mon, 08 Jun 2009 13:51:13 +1200 Subject: [time-nuts] Datron reference circuit error In-Reply-To: <4A2C6941.1030609@quackers.net> References: <4A2C6941.1030609@quackers.net> Message-ID: <4A2C6E91.1020604@xtra.co.nz> Bill Just noticed in passing that the equivalent circuit of the LTZ100A shown in the Datron reference at: ftp://ftp.quackers.net/DatronRef.PDF is incorrect. Linear technology seems to have finally corrected this error in its latest data sheet for the LTZ1000. Bruce From richiem at hughes.net Mon Jun 8 03:10:46 2009 From: richiem at hughes.net (Dick Moore) Date: Sun, 7 Jun 2009 20:10:46 -0700 Subject: [time-nuts] Need volt-nuts help In-Reply-To: References: Message-ID: <5F39A22B-6F05-4A4B-BCD6-AAA1B711A620@hughes.net> Hey Ed, thanks for the tips. The DC-200 has a quite different meter system based on the pix of the DC-150 you linked to. I did find a manual for sale for a model DC-200AR, and have inquired if the 200AR is at all similar to the 200C. If it is, I'm good to go. Thanks, Dick Moore On Jun 7, 2009, at 5:00 AM, time-nuts-request at febo.com wrote: > ------------------------------ > > Message: 3 > Date: Sat, 06 Jun 2009 17:11:30 -0600 > From: Ed Palmer > Subject: Re: [time-nuts] Need volt-nuts help > To: Discussion of precise time and frequency measurement > > Message-ID: <4A2AF7A2.7010809 at sasktel.net> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Sounds similar to one that I've got. CSC stands for "Calibration > Standards Corporation". Mine is DC-110B, but it looks identical to: > http://cgi.ebay.ca/Precision-DC-Null-Voltmeter-DC-150B_W0QQitemZ290321205779 > . I've seen an identical unit under the Honeywell brand. There are > manuals on *Bay for similar units. Search for > > "calibration standards" voltmeter > > I'd guess that the meter section is similar in all of them. I don't > have a manual for mine, unfortunately. > > Ed > > Dick Moore wrote: >> You all are an amazing resource, so even if this is not time-nuts >> material, someone of you may be able to shed some light. >> >> I picked up a differential voltmeter made by Precision Measurements >> Corp. It says it's brand is CSC (no info on what this stands for), >> model DC 200C. In general, it is similar to a Fluke 885 but with a >> much more readable meter, larger easier to use knobs, and overall >> fewer parts; plus a lot more empty space. The null detector/voltmeter >> section is not working, but the power supply and K-V divider are >> fine, >> as are all the switches. >> >> I've checked various sites for manuals with no luck, and also Googled >> and found nothing. Rather than try now to reverse engineer the >> schematic, I'm hoping one of you may know something about this >> machine. If nothing else it will be an interesting platform for play. >> >> Thx, >> Dick Moore >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > > ------------------------------ > > Message: 4 > Date: Sat, 06 Jun 2009 19:54:17 -0400 > From: neon John > Subject: [time-nuts] OT: Timer-counter wanted > To: time-nuts at febo.com > Message-ID: <4A2B01A9.3040308 at johngsbbq.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Hey guys, > > I'm looking for a counter/timer for my lab. I don't need anything of > Time Nuts grade, just a general purpose counter. I don't do sleazebay > plus I'd rather pass a few bux to a fellow time nutter. So if you > have > a spare one of fairly recent vintage, preferably not containing a > cooling fan, drop me a note. Please reply off-list: jgd at neon-john.com > > Thanks > John > -- > John DeArmond > Tellico Plains, Occupied TN > http://www.neon-john.com <-- email from here > http://www.johndearmond.com <-- Best damned Blog on the net > PGP key: wwwkeys.pgp.net: BCB68D77 > > > > ------------------------------ > > Message: 5 > Date: Sat, 6 Jun 2009 23:20:22 -0400 > From: > Subject: [time-nuts] Re :rubidium osc box > To: time-nuts at febo.com > Cc: time-nuts-request at febo.com > Message-ID: <20090606232022.M9RFI.220465.imail at eastrmwml46> > Content-Type: text/plain; charset=utf-8 > > If you want to go totally crazy on a shielded box, check out > Electronic Goldmine's MU metal sticky shielding. Used to be used on > CRT shields, etc. Probably not needed, but should kill a bunch of > LF noise. Make a sandwich over the wires entering the box, etc. > > N0UU > > > > ------------------------------ > > _______________________________________________ > time-nuts mailing list > time-nuts at febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > End of time-nuts Digest, Vol 59, Issue 15 > ***************************************** From Leigh at WA5ZNU.org Mon Jun 8 04:56:02 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr WA5ZNU) Date: Sun, 07 Jun 2009 21:56:02 -0700 Subject: [time-nuts] FE-5680A heat sink Message-ID: <4A2C99E2.5010803@WA5ZNU.org> I've attached an SMA connector to my FE-5680A and built an external linear power supply with a TO-3 7815. I ran the device today for about half an hour, and used an infrared sensing thermometer to measure the external case temperature. It got up to 48 C externally in the physics package area. I put a muffin fan on top and it brought it down to 38C but I don't think this is a good plan because I worry about the effects of the fan's magnetic field on the Rubidium system. I found in my junk box a finned Aluminum heat sink that's exactly the same size as the FE-5680A and plan to tap it around the edges for 4-40 hardware to attach to the many screw holes. Even so, this heat sink will be on the bottom, so the FE-5680A will have to be operated upside down for this to help. Has anybody got good thermal management solution for this device? This is the one currently selling on eBay in the 25x88x125mm chassis. Thanks, Leigh. From brice at weaponeer.com Mon Jun 8 05:30:00 2009 From: brice at weaponeer.com (brice at weaponeer.com) Date: Mon, 08 Jun 2009 05:30:00 +0000 Subject: [time-nuts] Vectron / WJ OXCO. Anyone know? / Freq counter needed. Message-ID: Vectron OXCO 233-5368-1 / WJ 708249-001 2.0" / 2.0" / 0.50" SMA output / mil spec, Al sheet surface mount, 4 mounting studs E1 orange / E2 black / E3 white / E4 (case ground) Probably FSN 5955-01-144-2344 Alt part # may be V26G893 . May be 100MHZ Can possibly get several more, new. Limited test equipment here, found conflicting data on part #'s. All needed is voltages or pinouts. Sounds silly, do not want to guess. Thanks, Bill William Rice Round Rock, Texas. ---- Frequency counter needed? If you are serious need more info. Range, Resolution, Size, Accuracy, Cost etc. Just messing around or are into serious counting. I can get you a stable older HP cheap with low resolution for basic measurements cheap.. Plenty of 2ghz plastic case units out there. 5370a good. Watch out for Cheesebay 5342A's. Have had many problems with front PCB's and connect with motherboard, also bad range switch. Many are Telco units and are burned out. Almost threw one of mine off a 2 story deck. The list goes on and on. Plenty of nice used newer units out there. Good luck. From cfharris at erols.com Mon Jun 8 11:58:26 2009 From: cfharris at erols.com (Chuck Harris) Date: Mon, 08 Jun 2009 07:58:26 -0400 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2C99E2.5010803@WA5ZNU.org> References: <4A2C99E2.5010803@WA5ZNU.org> Message-ID: <4A2CFCE2.5020107@erols.com> I'm puzzled. I admit that I don't have a lot of experience with Rb standards, but I do have a bit of experience with the HP-5065A Rb standard. In the 5065A, the entire physics package is enclosed in an oven. Assuming that your Rb is the same, and I believe it is, your plan to force the physics package to run at room temperature is just going to make the oven work harder in its never ending quest to maintain stable temperature. If you monitor the current draw of the 5680A, you will probably see that it goes up when you put a fan on it. Sometimes, you just have to let electronics run hot. What did the manufacturer suggest? -Chuck Harris Leigh L. Klotz, Jr WA5ZNU wrote: > I've attached an SMA connector to my FE-5680A and built an external > linear power supply with a TO-3 7815. > > I ran the device today for about half an hour, and used an infrared > sensing thermometer to measure the external case temperature. > It got up to 48 C externally in the physics package area. > I put a muffin fan on top and it brought it down to 38C but I don't > think this is a good plan because I worry about the effects of the fan's > magnetic field on the Rubidium system. > I found in my junk box a finned Aluminum heat sink that's exactly the > same size as the FE-5680A and plan to tap it around the edges for 4-40 > hardware to attach to the many screw holes. Even so, this heat sink > will be on the bottom, so the FE-5680A will have to be operated upside > down for this to help. > > Has anybody got good thermal management solution for this device? This > is the one currently selling on eBay in the 25x88x125mm chassis. > > Thanks, > Leigh. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From phk at phk.freebsd.dk Mon Jun 8 12:36:44 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 08 Jun 2009 12:36:44 +0000 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: Your message of "Mon, 08 Jun 2009 07:58:26 -0400." <4A2CFCE2.5020107@erols.com> Message-ID: <58562.1244464604@critter.freebsd.dk> In message <4A2CFCE2.5020107 at erols.com>, Chuck Harris writes: >> I ran the device today for about half an hour, and used an infrared >> sensing thermometer to measure the external case temperature. Be very careful about trusting this: you need to do some tricky calibrations to get anywhere near precise when you measure metal surfaces. The easy way, is to put a piece of duc[kt]tape on the metal surface and make sure your thermometer can see only that surface. Unfortunately, the tape will also act as insulation, so the result you get is not precise even then. >> It got up to 48 C externally in the physics package area. That's quite normal. Those small Rb's keep the internal temperature constant using heaters, which can raise the temperature and by being able to dump excess heat through their heat-sink to lower the temperature. You shouldn't run your Rb too hot, as this decreases the electronics lifetime and reduces the wiggle-room of the thermal management inside the device. On the other hand, cooling it too much will only increase the power drain for the heaters and increase the thermal gradients inside the unit, likely degrading thermal stability. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From cfharris at erols.com Mon Jun 8 13:31:08 2009 From: cfharris at erols.com (Chuck Harris) Date: Mon, 08 Jun 2009 09:31:08 -0400 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <58562.1244464604@critter.freebsd.dk> References: <58562.1244464604@critter.freebsd.dk> Message-ID: <4A2D129C.3060408@erols.com> Hi Poul, By replying to my reply to Leigh, and clipping out everything that I wrote (but my name), you seem to be attributing to me, what Leigh wrote. You then rephrased my statement about heaters in the physics package, restated my statement about extra cooling increasing the power drawn by the heaters. You then clarified things greatly by advising to not run the Rb too hot, but also don't cool it too much. ??? If you have so much to say to the original author, and nothing to say about my reply, wouldn't it have been be better to just reply to his message, instead of mine? -Chuck Harris Poul-Henning Kamp wrote: > In message <4A2CFCE2.5020107 at erols.com>, Chuck Harris writes: > >>> I ran the device today for about half an hour, and used an infrared >>> sensing thermometer to measure the external case temperature. > > Be very careful about trusting this: you need to do some tricky > calibrations to get anywhere near precise when you measure metal > surfaces. > > The easy way, is to put a piece of duc[kt]tape on the metal surface > and make sure your thermometer can see only that surface. > > Unfortunately, the tape will also act as insulation, so the result > you get is not precise even then. > >>> It got up to 48 C externally in the physics package area. > > That's quite normal. > > Those small Rb's keep the internal temperature constant using > heaters, which can raise the temperature and by being able to dump > excess heat through their heat-sink to lower the temperature. > > You shouldn't run your Rb too hot, as this decreases the electronics > lifetime and reduces the wiggle-room of the thermal management > inside the device. > > On the other hand, cooling it too much will only increase the > power drain for the heaters and increase the thermal gradients > inside the unit, likely degrading thermal stability. > > Poul-Henning > From fcdehaan_nospam at yahoo.com Mon Jun 8 15:02:24 2009 From: fcdehaan_nospam at yahoo.com (Frans) Date: Mon, 8 Jun 2009 08:02:24 -0700 (PDT) Subject: [time-nuts] Datron 4910 service manual request Message-ID: <144035.78368.qm@web54009.mail.re2.yahoo.com> Does anyone has a service manual for the Datron / Wavetek 4910 voltage standard. The output voltage is correct. I have problems with battery power. Met vriendelijke groeten, Regards, ing. Frans de Haan Haarlem the Netherlands From phk at phk.freebsd.dk Mon Jun 8 18:16:24 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 08 Jun 2009 18:16:24 +0000 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: Your message of "Mon, 08 Jun 2009 09:31:08 -0400." <4A2D129C.3060408@erols.com> Message-ID: <41499.1244484984@critter.freebsd.dk> In message <4A2D129C.3060408 at erols.com>, Chuck Harris writes: >If you have so much to say to the original author, and nothing to >say about my reply, wouldn't it have been be better to just reply >to his message, instead of mine? What can I say ? It was early in the morning ? See also: my .sig :-) Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From Murray.Greenman at rakon.com Mon Jun 8 18:42:47 2009 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Tue, 9 Jun 2009 06:42:47 +1200 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: References: Message-ID: Leigh, I agree with Chuck. I have both an FE-5650A and an FE-5680A. With the former I was concerned about the heat, and so ran it only for short periods, until I understood what was going on. I had the impression from the data sheet that there were different heatsink options for different temperature ranges, and I now believe this led me astray. With the FE-5680A I had the opportunity to study things in more detail. There is no temperature range specification that I could find, and no particular advice in the manual regarding installation. I ran the unit from regulated 15V DC, and monitored the supply current. With no extra cooling, the steady state current was about 700mA. With air blown over it, the current increased. With the unit placed in a poly bag, the current decreased to about 650mA. By the way, the current also decreased when operated from 17V DC. This tells me that the whole structure is part of the thermal package, and we should not attempt to force down the case temperature just because the unit runs hot. My experience with high performance OCXOs tells me that the thermal environment is carefully designed, and part of the calibration process - if you modify this environment (by cooling or extra insulation) you modify the thermal environment, and are at risk of modifying the performance. I'd leave well alone, and run the unit in an open, breeze-free environment. 73, Murray ZL1BPU From phk at phk.freebsd.dk Mon Jun 8 18:45:03 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 08 Jun 2009 18:45:03 +0000 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: Your message of "Tue, 09 Jun 2009 06:42:47 +1200." Message-ID: <49843.1244486703@critter.freebsd.dk> In message , "Murra y Greenman" writes: >With the FE-5680A I had the opportunity to study things in more detail. The PRS10 manual has some good info. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From cfharris at erols.com Mon Jun 8 19:04:02 2009 From: cfharris at erols.com (Chuck Harris) Date: Mon, 08 Jun 2009 15:04:02 -0400 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <41499.1244484984@critter.freebsd.dk> References: <41499.1244484984@critter.freebsd.dk> Message-ID: <4A2D60A2.3030409@erols.com> Hi Poul, I have long espoused that one should never attribute to malice that which can be more easily explained by ignorance. So, I didn't believe malice was involved. I just found your post curious, that's all. I'm pretty sure that mornings should be banned. -Chuck Harris Poul-Henning Kamp wrote: > In message <4A2D129C.3060408 at erols.com>, Chuck Harris writes: > >> If you have so much to say to the original author, and nothing to >> say about my reply, wouldn't it have been be better to just reply >> to his message, instead of mine? > > What can I say ? It was early in the morning ? > > See also: my .sig > > :-) > > Poul-Henning > > From imp at bsdimp.com Mon Jun 8 19:20:03 2009 From: imp at bsdimp.com (M. Warner Losh) Date: Mon, 08 Jun 2009 13:20:03 -0600 (MDT) Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2D60A2.3030409@erols.com> References: <41499.1244484984@critter.freebsd.dk> <4A2D60A2.3030409@erols.com> Message-ID: <20090608.132003.43012144.imp@bsdimp.com> In message: <4A2D60A2.3030409 at erols.com> Chuck Harris writes: : I'm pretty sure that mornings should be banned. Perty much... Nobody has a "breathalizer" to ensure that you are sufficiently caffeinated to give a good chance of a coherent reply :) Lord know that would have saved me much embarrassment over the years... However, since this is time-nuts, and we do deal with things on the hairy edge of what is possible, I'm sure someone will point to a side project that they've done that does just this, with schematics available for download form their web site :) Warner From bg at lysator.liu.se Mon Jun 8 20:33:00 2009 From: bg at lysator.liu.se (bg at lysator.liu.se) Date: Mon, 8 Jun 2009 22:33:00 +0200 (CEST) Subject: [time-nuts] FE-5680A thermal management In-Reply-To: <49843.1244486703@critter.freebsd.dk> References: <49843.1244486703@critter.freebsd.dk> Message-ID: <49381.87.227.52.225.1244493180.squirrel@webmail.lysator.liu.se> > In message , > "Murray Greenman" writes: > >>With the FE-5680A I had the opportunity to study things in more detail. > > The PRS10 manual has some good info. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk at FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by > incompetence. Ok, hope everyone can see what above was written by Poul and Murray respectively. ;-) For the FRS-C read page 7 (chapter 2.4 "Mounting" in the below manual. http://www.to-way.com/frs.pdf It says the "base plate" should never go above 65 deg C. -- Bj?rn From steve-krull at cox.net Mon Jun 8 20:38:15 2009 From: steve-krull at cox.net (Steve Krull) Date: Mon, 8 Jun 2009 16:38:15 -0400 (EDT) Subject: [time-nuts] Datron 4910 service manual request Message-ID: <1440281.29453.1244493495353.JavaMail.steve-krull@127.0.0.1> I'd like to find a copy, too. Same problem, and there doesn't seem to be replacement batteries that are fit-and-form equivalents. Thanks, Steve On Mon, Jun 8, 2009 at 3:35 PM , Frans wrote: > Does anyone has a service manual for the Datron / Wavetek 4910 voltage > standard. The output voltage is correct. I have problems with battery > power. > > Met vriendelijke groeten, Regards, > > ing. Frans de Haan > Haarlem > the Netherlands > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From J.Bastemeijer at tudelft.nl Mon Jun 8 20:48:43 2009 From: J.Bastemeijer at tudelft.nl (Jeroen Bastemeijer) Date: Mon, 08 Jun 2009 22:48:43 +0200 Subject: [time-nuts] Brandywine GPS-4 error In-Reply-To: <20090520155435.3FF4380152@mx4.tudelft.nl> References: <20090520155435.3FF4380152@mx4.tudelft.nl> Message-ID: <4A2D792B.6000300@tudelft.nl> Hi Jason, It has been quiet from my side for some time... I found a few spare minutes to further investigate my GPS4. Playing with the various jumpers did bring some response but no final solution. Next thing I did, I took out the EPROM and checked it with my Willem-programmer (a nice versatile cheap programmer (check Ebay)). I discoverd that the first addresses till $003000 are empty! It would be nice, if you, or someone is willing to check with their EPROM. The BIN-file can be read with the Willem-software program (http://se-ed.net/mpu51/) Looking forward to your response! 73 Jeroen PE1RGE -------------- next part -------------- A non-text attachment was scrubbed... Name: gps4.BIN Type: application/octet-stream Size: 65536 bytes Desc: not available URL: From tractorb at ihug.co.nz Mon Jun 8 20:49:43 2009 From: tractorb at ihug.co.nz (Dave Brown) Date: Tue, 9 Jun 2009 08:49:43 +1200 Subject: [time-nuts] FE-5680A thermal management References: Message-ID: <2ed501c9e87a$a7a4a850$7900a8c0@athlon1200> ----- Original Message ----- From: "Murray Greenman" To: Sent: Tuesday, June 09, 2009 6:42 AM Subject: [time-nuts] FE-5680A thermal management > Leigh, > > I agree with Chuck. I have both an FE-5650A and an FE-5680A. With > the > former I was concerned about the heat, and so ran it only for short > periods, until I understood what was going on. I had the impression > from > the data sheet that there were different heatsink options for > different > temperature ranges, and I now believe this led me astray. > > With the FE-5680A I had the opportunity to study things in more > detail. > There is no temperature range specification that I could find, and > no > particular advice in the manual regarding installation. I ran the > unit > from regulated 15V DC, and monitored the supply current. With no > extra > cooling, the steady state current was about 700mA. With air blown > over > it, the current increased. With the unit placed in a poly bag, the > current decreased to about 650mA. By the way, the current also > decreased > when operated from 17V DC. > > This tells me that the whole structure is part of the thermal > package, > and we should not attempt to force down the case temperature just > because the unit runs hot. My experience with high performance OCXOs > tells me that the thermal environment is carefully designed, and > part of > the calibration process - if you modify this environment (by cooling > or > extra insulation) you modify the thermal environment, and are at > risk of > modifying the performance. > > I'd leave well alone, and run the unit in an open, breeze-free > environment. > > 73, > Murray ZL1BPU Murray et al, The package of both units is clearly meant to be mounted on something-the real question is how much heat sinking would that something have provided? Changing the external heatsinking to achieve the nominal supply current at the nominal supply voltage would appear to be the only simple way to operate the units as intended. I've not gone through this exercise yet with the 5650, but I suspect the amount of heatsinking used is not that critical. Using a variable speed fan to determine the 'correct' mounting plate temperature (corresponding to nominal supply current/voltage) might be a good way to start. The design of a heatsink to achieve the same base plate temperature should be a trivial exercise. Constraining the 'ambient' air temperature to an appropriate range in the vicinity of the unit should certainly help as well. Regards DaveB, NZ From holrum at hotmail.com Mon Jun 8 21:16:51 2009 From: holrum at hotmail.com (Mark Sims) Date: Mon, 8 Jun 2009 21:16:51 +0000 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: References: Message-ID: Almost all rubidium standards DO specify the use of some form of a heat sink. For the FRK and M100 units this can be a heat sink with around 1" fins or just bolted to a metal plate or chassis. The military freq standard that had M100's in them had the unit mounted to a 5x5x.2" aluminum plate that was in turn bolted to the chassis. My Efratom PTB-100 time bases for the Tektronix TM500 mainframes have a large heat sink mounted to a FRK style oscillator. LPROs are supposed to be mounted to a metal chassis (they usually come with a thermal pad attached to them). I have seen them lose lock in free air. I saw one mounted in a piece of cell phone equipment. It was bolted to a large heat sink that formed most of the front of the enclosure. I have also seen FE-5680A's in their native habitat (again, cell phone equipment). They were mounted to a thick (1/8"?) PCB around 6x16". The side of the PCB that the 5680 was bolted to had a solid ground plane. The 5650A's had one side bolted to a metal chassis. ---------------------------------------- _________________________________________________________________ Hotmail? has ever-growing storage! Don?t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 From wje at quackers.net Mon Jun 8 21:46:26 2009 From: wje at quackers.net (wje) Date: Mon, 08 Jun 2009 17:46:26 -0400 Subject: [time-nuts] Datron 4910 service manual request In-Reply-To: <1440281.29453.1244493495353.JavaMail.steve-krull@127.0.0.1> References: <1440281.29453.1244493495353.JavaMail.steve-krull@127.0.0.1> Message-ID: <4A2D86B2.2070901@quackers.net> I have a manual, but it's hard-copy and LARGE. If you can narrow down your problem area, I'd be happy to scan some schematics. I also have two 4910's; I can probe some test points if you need some values. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Steve Krull wrote: >
I'd like > to find a copy, too. Same problem, and there doesn't seem to be > replacement batteries that are fit-and-form equivalents. > > Thanks, > > Steve > > > > On Mon, Jun 8, 2009 at 3:35 PM , Frans wrote: > >> Does anyone has a service manual for the Datron / Wavetek 4910 >> voltage standard. The output voltage is correct. I have problems with >> battery power. >> >> Met vriendelijke groeten, Regards, >> >> ing. Frans de Haan >> Haarlem >> the Netherlands >> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > >
From Leigh at WA5ZNU.org Tue Jun 9 02:10:01 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr WA5ZNU) Date: Mon, 08 Jun 2009 19:10:01 -0700 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2CFCE2.5020107@erols.com> References: <4A2C99E2.5010803@WA5ZNU.org> <4A2CFCE2.5020107@erols.com> Message-ID: <4A2DC479.8090408@WA5ZNU.org> Chuck, This device is a pull from a larger system, probably a cell site. It's clearly designed to be mounted on something, as it has lots and lots of holes around the edge. I suspect there's some thermal management that's missing. The FEI sheet gives "typical" data for the 0-50C range, though presumably that's ambient temperature. I don't want to cool the physics package per se, but I do want to at least approximate what kind of thermal solution ought to be supplied. Quite a few of these have been sold, and I've gotten good advice from others on this list about calibration. I'd hoped that someone would have experience with the thermal management. So far I've seen http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%200_4.pdf which shows (but doesn't describe) a heat sink on the bottom. Leigh. > I'm puzzled. I admit that I don't have a lot of experience with > Rb standards, but I do have a bit of experience with the HP-5065A > Rb standard. > > In the 5065A, the entire physics package is enclosed in an oven. > > Assuming that your Rb is the same, and I believe it is, your plan > to force the physics package to run at room temperature is just going > to make the oven work harder in its never ending quest to maintain > stable temperature. If you monitor the current draw of the 5680A, > you will probably see that it goes up when you put a fan on it. > > Sometimes, you just have to let electronics run hot. > > What did the manufacturer suggest? > > -Chuck Harris > > Leigh L. Klotz, Jr WA5ZNU wrote: >> I've attached an SMA connector to my FE-5680A and built an external >> linear power supply with a TO-3 7815. >> >> I ran the device today for about half an hour, and used an infrared >> sensing thermometer to measure the external case temperature. >> It got up to 48 C externally in the physics package area. >> I put a muffin fan on top and it brought it down to 38C but I don't >> think this is a good plan because I worry about the effects of the >> fan's magnetic field on the Rubidium system. >> I found in my junk box a finned Aluminum heat sink that's exactly the >> same size as the FE-5680A and plan to tap it around the edges for >> 4-40 hardware to attach to the many screw holes. Even so, this heat >> sink will be on the bottom, so the FE-5680A will have to be operated >> upside down for this to help. >> >> Has anybody got good thermal management solution for this device? >> This is the one currently selling on eBay in the 25x88x125mm chassis. >> >> Thanks, >> Leigh. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > the instructions there. From sar10538 at gmail.com Tue Jun 9 03:04:57 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Tue, 9 Jun 2009 15:04:57 +1200 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2D129C.3060408@erols.com> References: <58562.1244464604@critter.freebsd.dk> <4A2D129C.3060408@erols.com> Message-ID: <1231b6a80906082004j4168a430xa5fd3d0051e82a5@mail.gmail.com> Calm down Chuck, your doing it again. 2009/6/9 Chuck Harris : > Hi Poul, > > By replying to my reply to Leigh, and clipping out everything > that I wrote (but my name), you seem to be attributing to me, > what Leigh wrote. > > You then rephrased my statement about heaters in the physics > package, restated my statement about extra cooling increasing > the power drawn by the heaters. > > You then clarified things greatly by advising to not run the Rb > too hot, but also don't cool it too much. > > ??? > > If you have so much to say to the original author, and nothing to > say about my reply, wouldn't it have been be better to just reply > to his message, instead of mine? > > -Chuck Harris > > Poul-Henning Kamp wrote: >> >> In message <4A2CFCE2.5020107 at erols.com>, Chuck Harris writes: >> >>>> I ran the device today for about half an hour, and used an infrared >>>> sensing thermometer to measure the external case temperature. >> >> Be very careful about trusting this: ?you need to do some tricky >> calibrations to get anywhere near precise when you measure metal >> surfaces. >> >> The easy way, is to put a piece of duc[kt]tape on the metal surface >> and make sure your thermometer can see only that surface. >> >> Unfortunately, the tape will also act as insulation, so the result >> you get is not precise even then. >> >>>> It got up to 48 C externally in the physics package area. >> >> That's quite normal. >> >> Those small Rb's keep the internal temperature constant using >> heaters, which can raise the temperature and by being able to dump >> excess heat through their heat-sink to lower the temperature. >> >> You shouldn't run your Rb too hot, as this decreases the electronics >> lifetime and reduces the wiggle-room of the thermal management >> inside the device. >> >> On the other hand, cooling it too much will only increase the >> power drain for the heaters and increase the thermal gradients >> inside the unit, likely degrading thermal stability. >> >> Poul-Henning >> > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From cfharris at erols.com Tue Jun 9 03:38:31 2009 From: cfharris at erols.com (Chuck Harris) Date: Mon, 08 Jun 2009 23:38:31 -0400 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2DC479.8090408@WA5ZNU.org> References: <4A2C99E2.5010803@WA5ZNU.org> <4A2CFCE2.5020107@erols.com> <4A2DC479.8090408@WA5ZNU.org> Message-ID: <4A2DD937.2040702@erols.com> Hi Leigh, I just looked at a manual for an EG&G Rb standard module, and their spec is for -55C ambient to +68C baseplate. They had another spec that said MTBF >90,000 hours at 40C baseplate. Your FEI unit probably has a similarly worded spec. To me this means that the ideal (expected) temperature for the baseplate is 40C. If you are intending to operate your Rb block in a home environment, that has conditioned air, you can assume that the ambient temperature will be nominally 25C. I would start from that point, simply attach the block to the chassis, and measure the operating temperature of the baseplate. If it is around 40C, great! If it is much above 40C, you might want to add a heatsink. I wouldn't go out of my way to get below 40C. You can calculate the heatsink size knowing only the ambient temperature, and the power demand of the Rb block. But for operation in a civilized area, it is easier just to try a simple experiment. -Chuck Harris Leigh L. Klotz, Jr WA5ZNU wrote: > Chuck, > This device is a pull from a larger system, probably a cell site. It's > clearly designed to be mounted on something, as it has lots and lots of > holes around the edge. I suspect there's some thermal management that's > missing. The FEI sheet gives "typical" data for the 0-50C range, though > presumably that's ambient temperature. > I don't want to cool the physics package per se, but I do want to at > least approximate what kind of thermal solution ought to be supplied. > > Quite a few of these have been sold, and I've gotten good advice from > others on this list about calibration. I'd hoped that someone would > have experience with the thermal management. > > So far I've seen > http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%200_4.pdf > > which shows (but doesn't describe) a heat sink on the bottom. > > Leigh. From rexa at sonic.net Tue Jun 9 03:48:33 2009 From: rexa at sonic.net (Rex) Date: Mon, 08 Jun 2009 20:48:33 -0700 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2DC479.8090408@WA5ZNU.org> References: <4A2C99E2.5010803@WA5ZNU.org> <4A2CFCE2.5020107@erols.com> <4A2DC479.8090408@WA5ZNU.org> Message-ID: <4A2DDB91.1000605@sonic.net> Leigh L. Klotz, Jr WA5ZNU wrote: > Chuck, > This device is a pull from a larger system, probably a cell site. > It's clearly designed to be mounted on something, as it has lots and > lots of holes around the edge. I suspect there's some thermal > management that's missing. The FEI sheet gives "typical" data for the > 0-50C range, though presumably that's ambient temperature. > I don't want to cool the physics package per se, but I do want to at > least approximate what kind of thermal solution ought to be supplied. Several years back I bought a 5680A and mine came still mounted on the original (Lucent?) circuit board. There is a small amount of circuitry on one end, but most of the large board is just a solid plated area where the FE-5680A mounts. This is almost 100 in^2 plated on both sides, so an equivalent would be a sheet of aluminum about 7.25 x 13.5 inches. I'll let someone else translate that to an appropriate finned heatsink. > > Quite a few of these have been sold, and I've gotten good advice from > others on this list about calibration. I'd hoped that someone would > have experience with the thermal management. > > So far I've seen > http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%200_4.pdf > > which shows (but doesn't describe) a heat sink on the bottom. > > Leigh. > I never saw that particular pdf article before. It looks interesting. The 5680A I got was a bit different from most and I never found a way to program mine. I'll have to revisit the unit and see if the header connector he used works. I though I looked at that, but it has been a long time. Worth another attempt, I guess. -Rex, kk6mk >> I'm puzzled. I admit that I don't have a lot of experience with >> Rb standards, but I do have a bit of experience with the HP-5065A >> Rb standard. >> >> In the 5065A, the entire physics package is enclosed in an oven. >> >> Assuming that your Rb is the same, and I believe it is, your plan >> to force the physics package to run at room temperature is just going >> to make the oven work harder in its never ending quest to maintain >> stable temperature. If you monitor the current draw of the 5680A, >> you will probably see that it goes up when you put a fan on it. >> >> Sometimes, you just have to let electronics run hot. >> >> What did the manufacturer suggest? >> >> -Chuck Harris >> >> Leigh L. Klotz, Jr WA5ZNU wrote: >> >>> I've attached an SMA connector to my FE-5680A and built an external >>> linear power supply with a TO-3 7815. >>> >>> I ran the device today for about half an hour, and used an infrared >>> sensing thermometer to measure the external case temperature. >>> It got up to 48 C externally in the physics package area. >>> I put a muffin fan on top and it brought it down to 38C but I don't >>> think this is a good plan because I worry about the effects of the >>> fan's magnetic field on the Rubidium system. >>> I found in my junk box a finned Aluminum heat sink that's exactly >>> the same size as the FE-5680A and plan to tap it around the edges >>> for 4-40 hardware to attach to the many screw holes. Even so, this >>> heat sink will be on the bottom, so the FE-5680A will have to be >>> operated upside down for this to help. >>> >>> Has anybody got good thermal management solution for this device? >>> This is the one currently selling on eBay in the 25x88x125mm chassis. >>> >>> Thanks, >>> Leigh. >>> >>> From holrum at hotmail.com Tue Jun 9 04:18:15 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 9 Jun 2009 04:18:15 +0000 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: References: Message-ID: Also see my post from June of last year where I had measured the heat sink rise over ambient of several rubidium oscillators in free air... the FEI-5650 was very close to it's operating limit if operated in free air and not attached to something: http://www.febo.com/pipermail/time-nuts/2008-June/031695.html _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From namichie at gmail.com Tue Jun 9 05:40:42 2009 From: namichie at gmail.com (Neville Michie) Date: Tue, 9 Jun 2009 15:40:42 +1000 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: References: Message-ID: <98BEEF5A-E8C5-4FF5-B014-05E74F18AA38@gmail.com> Hi, some light might be shed on the heatsink problem by reading the data sheet for the LPRO 101 (Symmetricom) The units will have similar issues to cope with. The LPRO has temperature controlled lamp and filter, at different temperatures above 80C. Its power consumption is shown in a chart and is reduced as the temperature rises because the heating power needed becomes less. It must have a 17V internal series regulator, because total power consumption falls down to the minimum of 18V. MTBF is listed as 380kh at 20C, 320kh at 30C, 253kh at 40C, 189k at 50C and 134k at 60C. These are values that you would expect for most solid state boards. My solution was to put the device onto a finned heat sink in an aluminum box with a tiny 12V brushless fan, (40mm) which runs on 8 volts and is switched by a thermistor in the heatsink to keep the baseplate at 40C. This seems to be a good trade-off with MTBF, and the 10 MHZ xtal will run at a constant temperature of 40C + or - 0.05. I have not yet assembled the gear to measure how much its performance is improved. cheers, Neville Michie On 09/06/2009, at 2:18 PM, Mark Sims wrote: > > > Also see my post from June of last year where I had measured the > heat sink rise over ambient of several rubidium oscillators in free > air... the FEI-5650 was very close to it's operating limit if > operated in free air and not attached to something: > http://www.febo.com/pipermail/time-nuts/2008-June/031695.html > > _________________________________________________________________ > Lauren found her dream laptop. Find the PC that?s right for you. > http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. From bruce at ko4bb.com Tue Jun 9 06:00:29 2009 From: bruce at ko4bb.com (bruce at ko4bb.com) Date: Tue, 09 Jun 2009 02:00:29 -0400 Subject: [time-nuts] FE-5680A heat sink Message-ID: <11538240.856121244527229704.JavaMail.servlet@perfora> http://www.ham-radio.com/wa6vhs/Test%20equipment/FREQUENCY%20STANDARDS/FE-5680A/fei%205680a.pdf has high quality images of the 5680A and 5650A internal electronics. Bruce >Hi, >some light might be shed on the heatsink problem by reading the data >sheet for the LPRO 101 (Symmetricom) >The units will have similar issues to cope with. >The LPRO has temperature controlled lamp and filter, at different >temperatures above 80C. >Its power consumption is shown in a chart and is reduced as the >temperature rises because the heating power needed becomes less. >It must have a 17V internal series regulator, because total power >consumption falls down to the minimum of 18V. >MTBF is listed as 380kh at 20C, 320kh at 30C, 253kh at 40C, 189k at >50C and 134k at 60C. >These are values that you would expect for most solid state boards. >My solution was to put the device onto a finned heat sink in an >aluminum box with a tiny 12V brushless fan, (40mm) >which runs on 8 volts and is switched by a thermistor in the heatsink >to keep the baseplate at 40C. >This seems to be a good trade-off with MTBF, and the 10 MHZ xtal will >run at a constant temperature of 40C + or - 0.05. >I have not yet assembled the gear to measure how much its performance >is improved. >cheers, Neville Michie > > >On 09/06/2009, at 2:18 PM, Mark Sims wrote: > >> >> >> Also see my post from June of last year where I had measured the >> heat sink rise over ambient of several rubidium oscillators in free >> air... the FEI-5650 was very close to it's operating limit if >> operated in free air and not attached to something: >> http://www.febo.com/pipermail/time-nuts/2008-June/031695.html >> >> _________________________________________________________________ >> Lauren found her dream laptop. Find the PC that?s right for you. >> http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ >> time-nuts >> and follow the instructions there. > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. From bruce.griffiths at xtra.co.nz Tue Jun 9 03:21:52 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Tue, 09 Jun 2009 15:21:52 +1200 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2DC479.8090408@WA5ZNU.org> References: <4A2C99E2.5010803@WA5ZNU.org> <4A2CFCE2.5020107@erols.com> <4A2DC479.8090408@WA5ZNU.org> Message-ID: <4A2DD550.6010507@xtra.co.nz> Leigh Leigh L. Klotz, Jr WA5ZNU wrote: > Chuck, > This device is a pull from a larger system, probably a cell site. > It's clearly designed to be mounted on something, as it has lots and > lots of holes around the edge. I suspect there's some thermal > management that's missing. The FEI sheet gives "typical" data for the > 0-50C range, though presumably that's ambient temperature. > I don't want to cool the physics package per se, but I do want to at > least approximate what kind of thermal solution ought to be supplied. > > Quite a few of these have been sold, and I've gotten good advice from > others on this list about calibration. I'd hoped that someone would > have experience with the thermal management. > > So far I've seen > http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%200_4.pdf > > which shows (but doesn't describe) a heat sink on the bottom. > If the case is Mu metal or similar then the modification shown in the above article will likely destroy its magnetic shielding properties (unless its annealed in a hydrogen atmosphere at 400C for several hours after machining). The unit is designed like competitive units to be bolted to a heatsink or panel. The trick being to maintain the baseplate temperature within the specified temperature range (-5C to +50C). Since the power dissipation is low (11W @ 25C) you wont need an extremely low thermal resistance heatsink unless your ambient temperature is relatively high. If the ambient temperature is 40C then a 1C/W heatsink should maintain the base plate temperature below 60C. Just mount the 5680A on your heatsink and monitor the steady state heatsink temperature (with a thermocouple, RTD or other contact thermometer - could even use photochromic temperature sensing strips) both with the FE5680A upside down and the right way up. The infrared thermometer is unreliable unless its reading is corrected for the emissivity of the target in the 20um infrared region. Bruce > Leigh. > >> I'm puzzled. I admit that I don't have a lot of experience with >> Rb standards, but I do have a bit of experience with the HP-5065A >> Rb standard. >> >> In the 5065A, the entire physics package is enclosed in an oven. >> >> Assuming that your Rb is the same, and I believe it is, your plan >> to force the physics package to run at room temperature is just going >> to make the oven work harder in its never ending quest to maintain >> stable temperature. If you monitor the current draw of the 5680A, >> you will probably see that it goes up when you put a fan on it. >> >> Sometimes, you just have to let electronics run hot. >> >> What did the manufacturer suggest? >> >> -Chuck Harris >> >> Leigh L. Klotz, Jr WA5ZNU wrote: >>> I've attached an SMA connector to my FE-5680A and built an external >>> linear power supply with a TO-3 7815. >>> >>> I ran the device today for about half an hour, and used an infrared >>> sensing thermometer to measure the external case temperature. >>> It got up to 48 C externally in the physics package area. >>> I put a muffin fan on top and it brought it down to 38C but I don't >>> think this is a good plan because I worry about the effects of the >>> fan's magnetic field on the Rubidium system. >>> I found in my junk box a finned Aluminum heat sink that's exactly >>> the same size as the FE-5680A and plan to tap it around the edges >>> for 4-40 hardware to attach to the many screw holes. Even so, this >>> heat sink will be on the bottom, so the FE-5680A will have to be >>> operated upside down for this to help. >>> >>> Has anybody got good thermal management solution for this device? >>> This is the one currently selling on eBay in the 25x88x125mm chassis. >>> >>> Thanks, >>> Leigh. >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From bruce.griffiths at xtra.co.nz Tue Jun 9 03:55:43 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Tue, 09 Jun 2009 15:55:43 +1200 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2DC479.8090408@WA5ZNU.org> References: <4A2C99E2.5010803@WA5ZNU.org> <4A2CFCE2.5020107@erols.com> <4A2DC479.8090408@WA5ZNU.org> Message-ID: <4A2DDD3F.1000707@xtra.co.nz> Leigh Leigh L. Klotz, Jr WA5ZNU wrote: > > Chuck, > > This device is a pull from a larger system, probably a cell site. > > It's clearly designed to be mounted on something, as it has lots and > > lots of holes around the edge. I suspect there's some thermal > > management that's missing. The FEI sheet gives "typical" data for the > > 0-50C range, though presumably that's ambient temperature. > > I don't want to cool the physics package per se, but I do want to at > > least approximate what kind of thermal solution ought to be supplied. > > > > Quite a few of these have been sold, and I've gotten good advice from > > others on this list about calibration. I'd hoped that someone would > > have experience with the thermal management. > > > > So far I've seen > > http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%200_4.pdf > > > > which shows (but doesn't describe) a heat sink on the bottom. > > > If the case is Mu metal or similar then the modification shown in the above article will likely destroy its magnetic shielding properties (unless its annealed in a hydrogen atmosphere at 400C for several hours after machining). The unit is designed like competitive units to be bolted to a heatsink or panel. The trick being to maintain the baseplate temperature within the specified temperature range (-5C to +50C). Since the power dissipation is low (11W @ 25C) you wont need an extremely low thermal resistance heatsink unless your ambient temperature is relatively high. If the ambient temperature is 40C then a 1C/W heatsink should maintain the base plate temperature below 60C. Just mount the 5680A on your heatsink and monitor the steady state heatsink temperature (with a thermocouple, RTD or other contact thermometer - could even use photochromic temperature sensing strips) both with the FE5680A upside down and the right way up. The infrared thermometer is unreliable unless its reading is corrected for the emissivity of the target in the 20um infrared region. Bruce > > Leigh. > > > >> >> I'm puzzled. I admit that I don't have a lot of experience with >> >> Rb standards, but I do have a bit of experience with the HP-5065A >> >> Rb standard. >> >> >> >> In the 5065A, the entire physics package is enclosed in an oven. >> >> >> >> Assuming that your Rb is the same, and I believe it is, your plan >> >> to force the physics package to run at room temperature is just going >> >> to make the oven work harder in its never ending quest to maintain >> >> stable temperature. If you monitor the current draw of the 5680A, >> >> you will probably see that it goes up when you put a fan on it. >> >> >> >> Sometimes, you just have to let electronics run hot. >> >> >> >> What did the manufacturer suggest? >> >> >> >> -Chuck Harris >> >> >> >> Leigh L. Klotz, Jr WA5ZNU wrote: >> >>> >>> I've attached an SMA connector to my FE-5680A and built an external >>> >>> linear power supply with a TO-3 7815. >>> >>> >>> >>> I ran the device today for about half an hour, and used an infrared >>> >>> sensing thermometer to measure the external case temperature. >>> >>> It got up to 48 C externally in the physics package area. >>> >>> I put a muffin fan on top and it brought it down to 38C but I don't >>> >>> think this is a good plan because I worry about the effects of the >>> >>> fan's magnetic field on the Rubidium system. >>> >>> I found in my junk box a finned Aluminum heat sink that's exactly >>> >>> the same size as the FE-5680A and plan to tap it around the edges >>> >>> for 4-40 hardware to attach to the many screw holes. Even so, this >>> >>> heat sink will be on the bottom, so the FE-5680A will have to be >>> >>> operated upside down for this to help. >>> >>> >>> >>> Has anybody got good thermal management solution for this device? >>> >>> This is the one currently selling on eBay in the 25x88x125mm chassis. >>> >>> >>> >>> Thanks, >>> >>> Leigh. >>> >>> >>> >>> >>> >>> _______________________________________________ >>> >>> time-nuts mailing list -- time-nuts at febo.com >>> >>> To unsubscribe, go to >>> >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> >>> and follow the instructions there. >>> >>> >>> >> >> the instructions there. >> > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > From Murray.Greenman at rakon.com Tue Jun 9 19:03:02 2009 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Wed, 10 Jun 2009 07:03:02 +1200 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: References: Message-ID: I think we've all learned from this. Good info about the Efratom unit, and sounds as though we should aim for around 38C with the FEI units as well. The FE-5680 looks to be easier to deal with than the FE-5650, so I'll look into that first. Murray ZL1BPU From holrum at hotmail.com Tue Jun 9 18:32:06 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 9 Jun 2009 18:32:06 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: Well, it's air conditioning season again and I have been studying the effects of the varying temperature caused by AC cycling on the Thunderbolt output (as reported by the unit's internal monitoring messages). The attached image shows the effects of the temperature cycling on the Tbolt outputs when the unit is in free air. Each cycle of the AC produces around a 0.6 degree C change in the Thunderbolt temperature when the Tbolt and power supplies are in free air. This causes a 6.2 ns RMS shift in the PPS output and 0.046 ppb shift in the oscillator with each temperature cycle. Covering the Tbolt and the power supply with corrugated cardboard boxes (I used separate boxes for the Tbolt and the power supply) reduces the temperature swing to around 0.17C. The PPS output shift reduces to around 2.7 ns and the oscillator error to around 0.030 ppb. The boxes increase the Tbolt internal temperature around 3 degrees C. Placing the Tbolt in a corrugated cardboard box that was lined with waffled foam rubber reduced the temperature swings to around 0.060 degrees C (and increased the internal temperature by 10 degrees C). The PPS error reduced to around 2.3 ns and the osc error to around 0.027 ppb. By separately exposing the power supply to free air and insulating it, it appears the power supply contributes about 35 percent of the total error. A well insulated Thunderbolt and power supply produces the lowest amount of error at the expense of increased internal operating temperature (it went over 50C). A modest amount of insulation (placing the units in uninsulated corrugated boxs) produced almost as much improvement with only a 3C increase in electronics temperature. _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 -------------- next part -------------- A non-text attachment was scrubbed... Name: cycles.gif Type: image/gif Size: 36381 bytes Desc: not available URL: From phk at phk.freebsd.dk Tue Jun 9 19:12:53 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Tue, 09 Jun 2009 19:12:53 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Tue, 09 Jun 2009 18:32:06 GMT." Message-ID: <8906.1244574773@critter.freebsd.dk> In message , Mark Sims writes: >Placing the Tbolt in a corrugated cardboard box [...] We have discussed this topic some time back, and I relayed a suggestion from the Danish Metrology Lab: Use an unplugged fridge. Apart from a good air volume and sensible insulation, if you rip out the compressor, you can use the cooling circuit to do active temperature control if you want. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From geoff at g8kbz.demon.co.uk Tue Jun 9 19:19:59 2009 From: geoff at g8kbz.demon.co.uk (Geoff Powell) Date: Tue, 9 Jun 2009 20:19:59 +0100 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: <2ed501c9e87a$a7a4a850$7900a8c0@athlon1200> References: <2ed501c9e87a$a7a4a850$7900a8c0@athlon1200> Message-ID: In article <2ed501c9e87a$a7a4a850$7900a8c0 at athlon1200>, Dave Brown writes > >Murray et al, >The package of both units is clearly meant to be mounted on >something-the real question is how much heat sinking would that >something have provided? Changing the external heatsinking to achieve >the nominal supply current at the nominal supply voltage would appear >to be the only simple way to operate the units as intended. > >I've not gone through this exercise yet with the 5650, but I suspect >the amount of heatsinking used is not that critical. Using a variable >speed fan to determine the 'correct' mounting plate temperature >(corresponding to nominal supply current/voltage) might be a good way >to start. The design of a heatsink to achieve the same base plate >temperature should be a trivial exercise. >Constraining the 'ambient' air temperature to an appropriate range in >the vicinity of the unit should certainly help as well. > Guys, As a datum point, I have an FE5650A mounted in a 2U 19 inch chassis. This chassis is a Tait T800 reference frequency generator, for use as a controller in quasi-synchronous wide-area mobile radio systems. That chassis has the FE-5650A mounted on an extra block of aluminium, with some finning attached if memory serves, and fitted inside the chassis. There is no internal airflow over the mounting plate, and no external fins on the case. I have the manual for this unit, and Tait make no mention of any special thermal requirements. This suggests that, beyond mounting the Rb on sufficient metal, the exact requirements are non-critical. I'll get the unit out of store and take photos/measurements if required. -- Geoff Powell From holrum at hotmail.com Tue Jun 9 19:47:04 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 9 Jun 2009 19:47:04 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: I think that using a well insulated box (like a fridge) is probably not going to improve things much with a Thunderbolt. The very modest improvement going from a simple cardboard box (and .17C shifts) to an insulated box (and .060C shifts) seems to imply that we are close to the inherent noise limits of the Tbolt. If you can get your Tbolt/power supply isolated enough to keep the temperature cycles below around 0.2C you should be doing well. The better the insulation, the higher the electronics temperature (and its potential effect on reliability). The Tbolt goes into a major alarm state at 60C. Lady Heather flags temperatures of 50-60C in yellow. The one thing that a larger enclosure does provide is better buffering of the temperature. You can get better isolation from ambient with less effect on the electronics temperature that a small, tightly insulated box can provide. Perhaps something like a small picnic cooler would be a good compromise... but it is hard to beat the cost:effectiveness ratio of a simple cardboard box. The air conditioning/heating cycles typically occur over a 15 minute to 1 hour range. The Tbolt seems to handle longer term temperature shifts (such as daily variations that you might see when climate control systems are not in use) much better. _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From phk at phk.freebsd.dk Tue Jun 9 20:03:39 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Tue, 09 Jun 2009 20:03:39 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Tue, 09 Jun 2009 19:47:04 GMT." Message-ID: <9160.1244577819@critter.freebsd.dk> In message , Mark Sims writes: >I think that using a well insulated box [...] The point for timenuts is not just the thermal resistance, but more importantly the thermal *impedance*: you want to low-pass filter the thermal changes so that they all happen in the area where the PLL can cope with them. Thermal resistance is about insulation, thermal impedance is about (thermal) mass. So you significant mass and volume (like a fridge) not light and small (like a cardboard box). When metrology people really want to keep things at the same temperature, they mount them in oil-baths (for good thermal contact) in the middle of a block of aluminium, typically 2'x2'x1' (for thermal impedance) which is again insulated with 1" styrofoam, all of this mounted in a plywoodbox, set on rubber-wheels to get it off the floor (for thermal resistance). If they are really into this, they cover the plywood with high-quality (noble-) metal foil, to maximize reflectivity and minimize emissivity, so that the black-body radiation from devices and humans in the lab does not affect the temperature interface as much. Then they leave it alone for "some weeks" in their temperature controlled lab so the temperature can stabilize. At this point they may start to wonder how they can verify the pt100 temperature sensor they put in the middle of it all actually works when the temperature never changes... Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From eric.n5ebw at gmail.com Tue Jun 9 22:31:33 2009 From: eric.n5ebw at gmail.com (Eric Wolf) Date: Tue, 9 Jun 2009 17:31:33 -0500 Subject: [time-nuts] For Sale: AVCOM MDM-1575-8 GPS antenna splitter Message-ID: Sorry my post to the list is not meaningful and is something for sale, extenuating circumstances of life at the moment. Up for sale is an AVCOM MDM-1575-8 GPS antenna splitter, in good working condition. This unit was made for one company who used it for GPS work, and was not a full production unit. The heart of the unit is a passive Mini-Circuits ZB8PD-2 Power Splitter being fed by an amplified GPS input signal. According to the specs for the Mini-Circuits Splitter, it uses a port isolation of 20-25 dB. The unit powers on, and is guaranteed against DOA. All ports have been verified working (By another Time Nuts list member no less!), and the +5 volt DC signal also works. There's not much technical specification on the unit available per AVCOM, but they confirmed that all ports are amplified so that you have unity gain out after splitting 8 ways, inputs are DC blocked, and there is 5V LNA out on each port for powering a GPS antenna. If there are any questions that I can't answer (What's in this post is basically what I know, and I think all they know too), AVCOM of Virginia can be reached at 804-794-2500. I do have pictures of the unit and documentation on the power splitter in PDF format upon request. Please contact me off-list if interested. First offer of $225 USD + shipping takes it! I have no use for this item and don't foresee needing it in the future, so I would like someone else to get some use out of it. -Eric, N5EBW From bruce.griffiths at xtra.co.nz Tue Jun 9 22:33:22 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 10 Jun 2009 10:33:22 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <9160.1244577819@critter.freebsd.dk> References: <9160.1244577819@critter.freebsd.dk> Message-ID: <4A2EE332.9030803@xtra.co.nz> Poul-Henning Kamp wrote: > In message , Mark Sims writes: > > >> I think that using a well insulated box [...] >> > > The point for timenuts is not just the thermal resistance, but more > importantly the thermal *impedance*: you want to low-pass filter > the thermal changes so that they all happen in the area where the > PLL can cope with them. > > Thermal resistance is about insulation, thermal impedance is > about (thermal) mass. > > So you significant mass and volume (like a fridge) not light and > small (like a cardboard box). > > When metrology people really want to keep things at the same > temperature, they mount them in oil-baths (for good thermal contact) > in the middle of a block of aluminium, typically 2'x2'x1' (for > thermal impedance) which is again insulated with 1" styrofoam, all > of this mounted in a plywoodbox, set on rubber-wheels to get it off > the floor (for thermal resistance). > > If they are really into this, they cover the plywood with high-quality > (noble-) metal foil, to maximize reflectivity and minimize emissivity, > so that the black-body radiation from devices and humans in the lab > does not affect the temperature interface as much. > > Then they leave it alone for "some weeks" in their temperature > controlled lab so the temperature can stabilize. > > At this point they may start to wonder how they can verify the pt100 > temperature sensor they put in the middle of it all actually works > when the temperature never changes... > > Poul-Henning > > Poul The thermal time constant (not the thermal impedance per se) is what matters when one is trying to reduce the effective amplitude of temperature fluctuations due to air conditioner cycling. Adding mass increases the thermal capacitance adding insulation increases the thermal resistance. It is possible to construct an enclosure with a long thermal time constant together with relatively low thermal resistance so that the temperature of a GPSDO or similar device within the enclosure only increases by a relatively small amount. Multiple alternating layers of thermal conductor and thermal insulator reduce thermal gradients as well as temperature fluctuations. Having an outer conductive layer reduces the temperature gradients over the insulator surface. Readily available inexpensive aluminium foil is a cheaper alternative to expensive noble metal foils. Silica aerogel is one of the most effective insulators. Balsa wood has been used as the insulator in portable temperature controlled ensclosures for standard cells. Bruce From tvb at LeapSecond.com Tue Jun 9 22:43:38 2009 From: tvb at LeapSecond.com (Tom Van Baak) Date: Tue, 9 Jun 2009 15:43:38 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature References: <9160.1244577819@critter.freebsd.dk> <4A2EE332.9030803@xtra.co.nz> Message-ID: <90E721F2E6DC4BCA9022893817F7CE1E@pc52> > Adding mass increases the thermal capacitance adding insulation > increases the thermal resistance. > It is possible to construct an enclosure with a long thermal time > constant together with relatively low thermal resistance so that the > temperature of a GPSDO or similar device within the enclosure only > increases by a relatively small amount. > > Multiple alternating layers of thermal conductor and thermal insulator > reduce thermal gradients as well as temperature fluctuations. > > Having an outer conductive layer reduces the temperature gradients over > the insulator surface. > > Readily available inexpensive aluminium foil is a cheaper alternative to > expensive noble metal foils. > > Silica aerogel is one of the most effective insulators. > > Balsa wood has been used as the insulator in portable temperature > controlled ensclosures for standard cells. > > Bruce And the amazing thing is that this temperature control double oven technology for oscillators was well advanced in 1931. See: http://www.leapsecond.com/museum/gr676b-50kc/ and especially the "temperature control apparatus" patent: http://www.leapsecond.com/museum/gr676b-50kc/US1967185.pdf /tvb From bruce.griffiths at xtra.co.nz Tue Jun 9 22:59:03 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 10 Jun 2009 10:59:03 +1200 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: References: Message-ID: <4A2EE937.6050707@xtra.co.nz> Murray Greenman wrote: > I think we've all learned from this. Good info about the Efratom unit, > and sounds as though we should aim for around 38C with the FEI units as > well. The FE-5680 looks to be easier to deal with than the FE-5650, so > I'll look into that first. > > Murray ZL1BPU > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > For those who haven't found it here is a link to a manual for one version of the 5680A: http://www.ham-radio.com/wa6vhs/Test%20equipment/FREQUENCY%20STANDARDS/FE-5680A/5680%20TECH%20MANUAL.pdf Bruce From jfor at quik.com Tue Jun 9 23:26:34 2009 From: jfor at quik.com (J. Forster) Date: Tue, 9 Jun 2009 16:26:34 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A2EE332.9030803@xtra.co.nz> References: <9160.1244577819@critter.freebsd.dk> <4A2EE332.9030803@xtra.co.nz> Message-ID: <2293.12.6.201.142.1244589994.squirrel@popacctsnew.quik.com> >> The point for timenuts is not just the thermal resistance, but more >> importantly the thermal *impedance*: you want to low-pass filter >> the thermal changes so that they all happen in the area where the >> PLL can cope with them. >> >> Thermal resistance is about insulation, thermal impedance is >> about (thermal) mass. Not really. Consider a one dimensional model, with the controlled space onb the left and the ambient on the right: |------| | | Osc |===========| Ambient |======| | T mass > The thermal time constant (not the thermal impedance per se) is what > matters when one is trying to reduce the effective amplitude of > temperature fluctuations due to air conditioner cycling. > Adding mass increases the thermal capacitance adding insulation > increases the thermal resistance. True > It is possible to construct an enclosure with a long thermal time > constant together with relatively low thermal resistance so that the > temperature of a GPSDO or similar device within the enclosure only > increases by a relatively small amount. Nope. This is essentially a thermal low pass filter. The same resistance enters into the time constant and thermal resistance to the ambient. The only way to increase the thermal TC, while maintaining the resistance, is to add thermal mass to the Oscillator assembly. (Increase the C with constant R) -John > Multiple alternating layers of thermal conductor and thermal insulator > reduce thermal gradients as well as temperature fluctuations. > > Having an outer conductive layer reduces the temperature gradients over > the insulator surface. > > Readily available inexpensive aluminium foil is a cheaper alternative to > expensive noble metal foils. > > Silica aerogel is one of the most effective insulators. > > Balsa wood has been used as the insulator in portable temperature > controlled ensclosures for standard cells. > > Bruce From bruce.griffiths at xtra.co.nz Wed Jun 10 00:21:01 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 10 Jun 2009 12:21:01 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <2293.12.6.201.142.1244589994.squirrel@popacctsnew.quik.com> References: <9160.1244577819@critter.freebsd.dk> <4A2EE332.9030803@xtra.co.nz> <2293.12.6.201.142.1244589994.squirrel@popacctsnew.quik.com> Message-ID: <4A2EFC6D.4020205@xtra.co.nz> J. Forster wrote: >>> The point for timenuts is not just the thermal resistance, but more >>> importantly the thermal *impedance*: you want to low-pass filter >>> the thermal changes so that they all happen in the area where the >>> PLL can cope with them. >>> >>> Thermal resistance is about insulation, thermal impedance is >>> about (thermal) mass. >>> > > Not really. > > Consider a one dimensional model, with the controlled space onb the left > and the ambient on the right: > > |------| | > | Osc |===========| Ambient > |======| | > T mass > > >> The thermal time constant (not the thermal impedance per se) is what >> matters when one is trying to reduce the effective amplitude of >> temperature fluctuations due to air conditioner cycling. >> Adding mass increases the thermal capacitance adding insulation >> increases the thermal resistance. >> > > True > > >> It is possible to construct an enclosure with a long thermal time >> constant together with relatively low thermal resistance so that the >> temperature of a GPSDO or similar device within the enclosure only >> increases by a relatively small amount. >> > > Nope. This is essentially a thermal low pass filter. The same resistance > enters into the time constant and thermal resistance to the ambient. The > only way to increase the thermal TC, while maintaining the resistance, is > to add thermal mass to the Oscillator assembly. (Increase the C with > constant R) > > -John > > Incorrect assumption, I was discussing the thermal characteristics of the added enclosure. The thermal resistance of the external enclosure to the ambient isn't fixed. Just adding mass to the case without ensuring that the additional mass has a well defined (and not too low) thermal resistance to ambient can be relatively ineffective. Adding just a little insulation to the added thermal mass can dramatically increase the thermal time constant combined with a modest increase in operating temperature. > >> Multiple alternating layers of thermal conductor and thermal insulator >> reduce thermal gradients as well as temperature fluctuations. >> >> Having an outer conductive layer reduces the temperature gradients over >> the insulator surface. >> >> Readily available inexpensive aluminium foil is a cheaper alternative to >> expensive noble metal foils. >> >> Silica aerogel is one of the most effective insulators. >> >> Balsa wood has been used as the insulator in portable temperature >> controlled ensclosures for standard cells. >> >> Bruce >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > Bruce From jfor at quik.com Wed Jun 10 00:36:10 2009 From: jfor at quik.com (J. Forster) Date: Tue, 9 Jun 2009 17:36:10 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A2EFC6D.4020205@xtra.co.nz> References: <9160.1244577819@critter.freebsd.dk> <4A2EE332.9030803@xtra.co.nz> <2293.12.6.201.142.1244589994.squirrel@popacctsnew.quik.com> <4A2EFC6D.4020205@xtra.co.nz> Message-ID: <2522.12.6.201.142.1244594170.squirrel@popacctsnew.quik.com> > J. Forster wrote: >>>> The point for timenuts is not just the thermal resistance, but more >>>> importantly the thermal *impedance*: you want to low-pass filter >>>> the thermal changes so that they all happen in the area where the >>>> PLL can cope with them. >>>> >>>> Thermal resistance is about insulation, thermal impedance is >>>> about (thermal) mass. >>>> >> >> Not really. >> >> Consider a one dimensional model, with the controlled space onb the left >> and the ambient on the right: >> >> |------| | >> | Osc |===========| Ambient >> |======| | >> T mass >> >> >>> The thermal time constant (not the thermal impedance per se) is what >>> matters when one is trying to reduce the effective amplitude of >>> temperature fluctuations due to air conditioner cycling. >>> Adding mass increases the thermal capacitance adding insulation >>> increases the thermal resistance. >>> >> >> True >> >> >>> It is possible to construct an enclosure with a long thermal time >>> constant together with relatively low thermal resistance so that the >>> temperature of a GPSDO or similar device within the enclosure only >>> increases by a relatively small amount. >>> >> >> Nope. This is essentially a thermal low pass filter. The same resistance >> enters into the time constant and thermal resistance to the ambient. The >> only way to increase the thermal TC, while maintaining the resistance, >> is >> to add thermal mass to the Oscillator assembly. (Increase the C with >> constant R) >> >> -John >> >> > Incorrect assumption, I was discussing the thermal characteristics of > the added enclosure. > The thermal resistance of the external enclosure to the ambient isn't > fixed. > > Just adding mass to the case without ensuring that the additional mass > has a well defined (and not too low) thermal resistance to ambient can > be relatively ineffective. I never suggested adding thermal mass to the case, but to the oscillator package to lengthen the thermal TC. (Tmass above) > Adding just a little insulation to the added thermal mass can > dramatically increase the thermal time constant combined with a modest > increase in operating temperature. Adding insulation between the oscillator and the ambient will lengthen the TC but also increase the temperature rise. >>> Multiple alternating layers of thermal conductor and thermal insulator >>> reduce thermal gradients as well as temperature fluctuations. >>> >>> Having an outer conductive layer reduces the temperature gradients over >>> the insulator surface. >>> >>> Readily available inexpensive aluminium foil is a cheaper alternative >>> to >>> expensive noble metal foils. >>> >>> Silica aerogel is one of the most effective insulators. >>> >>> Balsa wood has been used as the insulator in portable temperature >>> controlled ensclosures for standard cells. >>> >>> Bruce >>> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > Bruce > > From Leigh at WA5ZNU.org Wed Jun 10 01:42:21 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr WA5ZNU) Date: Tue, 09 Jun 2009 18:42:21 -0700 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: References: Message-ID: <4A2F0F7D.3040606@WA5ZNU.org> Yes, thank you to all. I'll go ahead with the heat sink on the bottom and consider a fan nearby. Leigh/WA5ZNU > I think we've all learned from this. Good info about the Efratom unit, > and sounds as though we should aim for around 38C with the FEI units as > well. The FE-5680 looks to be easier to deal with than the FE-5650, so > I'll look into that first. > > Murray ZL1BPU > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From Leigh at WA5ZNU.org Wed Jun 10 01:51:02 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr WA5ZNU) Date: Tue, 09 Jun 2009 18:51:02 -0700 Subject: [time-nuts] FE-5680A heat sink In-Reply-To: <4A2DD550.6010507@xtra.co.nz> References: <4A2C99E2.5010803@WA5ZNU.org> <4A2CFCE2.5020107@erols.com> <4A2DC479.8090408@WA5ZNU.org> <4A2DD550.6010507@xtra.co.nz> Message-ID: <4A2F1186.6070806@WA5ZNU.org> Bruce, Thank you for this point. I've seen Mu metal competitors but I can't tell what the case is made from. Pretty much everybody I've seen on this has had to make some kind of allowance for getting the RF out. I drilled a hole for an SMA connector and had it exit on the digital half of the chassis (not the "physics" half), as they're separated by a very large bar, perhaps brass. It has a few ways to get wires through, but it didn't seem to be a good idea. The SMA is a jumper I bought on eBay from a Chinese manufacturer, with an IPX connector on one end and the SMA bulkhead on the other. Hirose U.Fl and IPX are said to be compatible, but it didn't look like it wanted to stay down, so I tacked a wire to the head of the IPX connector put a brass 2-54 nut on a nearby post to ensure mechanical connection. I think this is better than soldering open coax to the connector, but given the short size and low frequency (10 Mhz) it's probably not a concern. So, I probably did something bad to the magic Mu metal annealing by drilling a hole, but it's as far as I could get over on the digital side of the brass divider. At this point I have nothing calibrated that I can measure the device with and see if there's any small magnetic influence, but perhaps someday I will, or maybe someone else would like to compare with another device sometime. It might have been possible to re-purpose a pin from the existing RS232 connector, and perhaps others who buy this same run of device may want to investigate that. Leigh. Bruce Griffiths wrote: > Leigh L. Klotz, Jr WA5ZNU wrote: > >> So far I've seen >> http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%200_4.pdf >> >> > > If the case is Mu metal or similar then the modification shown in the > above article will likely destroy its magnetic shielding properties > (unless its annealed in a hydrogen atmosphere at 400C for several hours > after machining). > > From phk at phk.freebsd.dk Wed Jun 10 07:13:19 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Wed, 10 Jun 2009 07:13:19 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Wed, 10 Jun 2009 12:21:01 +1200." <4A2EFC6D.4020205@xtra.co.nz> Message-ID: <2010.1244617999@critter.freebsd.dk> In message <4A2EFC6D.4020205 at xtra.co.nz>, Bruce Griffiths writes: Bruce, >>> The thermal time constant (not the thermal impedance per se) is what >>> matters [...] That is pretty much exactly the (mis-)definition of thermal impedance. Thermal timeconstant or thermal corner-frequency had been much better names. >>> It is possible to construct an enclosure with a long thermal time >>> constant together with relatively low thermal resistance so that the >>> temperature of a GPSDO or similar device within the enclosure only >>> increases by a relatively small amount. >> >> Nope. This is essentially a thermal low pass filter. Well, yes you can, but it is not very useful: A really huge block of metal will do that: It can transfer a lot of heat (=low resistance), but will take a long time doing so (=high impedance). >Adding just a little insulation to the added thermal mass can >dramatically increase the thermal time constant combined with a modest >increase in operating temperature. Isn't that exactly what I explained initially ? A huge block of aluminium, encased in 1" of styrofoam ? >>> Readily available inexpensive aluminium foil is a cheaper alternative to >>> expensive noble metal foils. But it does not stay as reflective. By the time you add this layer to the construction I mentioned, you care about the difference between 0.98 and 0.99. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From magnus at rubidium.dyndns.org Wed Jun 10 08:15:37 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 10 Jun 2009 10:15:37 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <2010.1244617999@critter.freebsd.dk> References: <2010.1244617999@critter.freebsd.dk> Message-ID: <4A2F6BA9.9090205@rubidium.dyndns.org> Poul-Henning Kamp skrev: > In message <4A2EFC6D.4020205 at xtra.co.nz>, Bruce Griffiths writes: > > Bruce, > >>>> The thermal time constant (not the thermal impedance per se) is what >>>> matters [...] > > That is pretty much exactly the (mis-)definition of thermal impedance. > > Thermal timeconstant or thermal corner-frequency had been much better names. Thermal impedances can be divided into thermal resistance and thermal capacitivity, these forms filters which in a 1D representation would be a number of RC-links of various values. Thermal time constant and total thermal conductance is aspects of the static and dynamic properties that the structure has. >>>> It is possible to construct an enclosure with a long thermal time >>>> constant together with relatively low thermal resistance so that the >>>> temperature of a GPSDO or similar device within the enclosure only >>>> increases by a relatively small amount. >>> Nope. This is essentially a thermal low pass filter. > > Well, yes you can, but it is not very useful: > > A really huge block of metal will do that: It can transfer a lot > of heat (=low resistance), but will take a long time doing so (=high > impedance). Depends on the metal. >> Adding just a little insulation to the added thermal mass can >> dramatically increase the thermal time constant combined with a modest >> increase in operating temperature. > > Isn't that exactly what I explained initially ? > > A huge block of aluminium, encased in 1" of styrofoam ? There are many ways to say the same thing, don't argue with the guy just phrasing it differently. Discuss the various merits of different approaches instead. >>>> Readily available inexpensive aluminium foil is a cheaper alternative to >>>> expensive noble metal foils. > > But it does not stay as reflective. By the time you add this layer to > the construction I mentioned, you care about the difference between > 0.98 and 0.99. It is interesting to see you being more extreme then Bruce. At the same time, you are discussing two different approaches, not a single one. I think discussing a general hints and tips that can apply to many pratical cases is more useful at this stage then discussing a detailed extreme solution only. Nobody having a thermal inductive material around? That would be very usefull to handle temperature shifts. Cheers, Magnus From james.p.lux at jpl.nasa.gov Wed Jun 10 13:12:04 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Wed, 10 Jun 2009 06:12:04 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A2F6BA9.9090205@rubidium.dyndns.org> Message-ID: On 6/10/09 1:15 AM, "Magnus Danielson" wrote: > > > Nobody having a thermal inductive material around? That would be very > usefull to handle temperature shifts. Let's see.. If heat flow (watts) is the analog of current (Amps), and delta T is the analog of voltage, what would a thermal inductor be... It would have to have a delta T that is proportional to the rate of change of heat flow. A tough concept to wrap my early morning before coffee brain around.. BTW There are "thermal batteries" which contain a phase change material, like wax, in them, but just like real batteries they're more analogous to a capacitor. One could synthesize a thermal inductor with an active device (e.g. A heat pump of some sort), just as one can synthesize an inductor with a op amp and Rs and Cs (and some externally supplied energy) From robert8rpi at yahoo.co.uk Wed Jun 10 18:52:22 2009 From: robert8rpi at yahoo.co.uk (Robert Atkinson) Date: Wed, 10 Jun 2009 18:52:22 +0000 (GMT) Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: <231420.47114.qm@web27101.mail.ukl.yahoo.com> Interestingly, the packing instructions for the Solartron 7081 81/2 digit voltmeter shows two "thermal inertia bottles" close to the instument. These provide a thermal mass that works with the insulation to reduce the rate of temperature change at the unit. This will also filter short duration transients. So a cardboard box with a couple of bottles of water in it would make a good enclosure. Or just leave the beer in the cooler :-) Robert G8RPI. --- On Tue, 9/6/09, Poul-Henning Kamp wrote: > From: Poul-Henning Kamp > Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature > To: "Discussion of precise time and frequency measurement" > Date: Tuesday, 9 June, 2009, 9:03 PM > In message , > Mark Sims writes: > > >I think that using a well insulated box [...] > > The point for timenuts is not just the thermal resistance, > but more > importantly the thermal *impedance*: you want to low-pass > filter > the thermal changes so that they all happen in the area > where the > PLL can cope with them. > > Thermal resistance is about insulation, thermal impedance > is > about (thermal) mass. > > So you significant mass and volume (like a fridge) not > light and > small (like a cardboard box). > > When metrology people really want to keep things at the > same > temperature, they mount them in oil-baths (for good thermal > contact) > in the middle of a block of aluminium, typically 2'x2'x1' > (for > thermal impedance) which is again insulated with 1" > styrofoam, all > of this mounted in a plywoodbox, set on rubber-wheels to > get it off > the floor (for thermal resistance). > > If they are really into this, they cover the plywood with > high-quality > (noble-) metal foil, to maximize reflectivity and minimize > emissivity, > so that the black-body radiation from devices and humans in > the lab > does not affect the temperature interface as much. > > Then they leave it alone for "some weeks" in their > temperature > controlled lab so the temperature can stabilize. > > At this point they may start to wonder how they can verify > the pt100 > temperature sensor they put in the middle of it all > actually works > when the temperature never changes... > > Poul-Henning > > -- > Poul-Henning Kamp? ? ???| UNIX > since Zilog Zeus 3.20 > phk at FreeBSD.ORG? > ? ? ???| TCP/IP since RFC 956 > FreeBSD committer? ? ???| BSD > since 4.3-tahoe? ? > Never attribute to malice what can adequately be explained > by incompetence. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From djl at montana.com Wed Jun 10 19:04:18 2009 From: djl at montana.com (Don Latham) Date: Wed, 10 Jun 2009 13:04:18 -0600 (MDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <231420.47114.qm@web27101.mail.ukl.yahoo.com> References: <231420.47114.qm@web27101.mail.ukl.yahoo.com> Message-ID: <7995b5e60f1e044eb01ed681a05915f0.squirrel@webmail.montana.com> In one of my other incarnations, radio astronomy (definitely amateur if not downright amateurish) an automotive 12 v thermoelectric cooler was converted by one of the group into a servoed "constant" temperature box. Those of time persuasion might want to try that. Note the small auto coolers can just as well be converted to a constant temperature heated box as well. Don Robert Atkinson > > Interestingly, the packing instructions for the Solartron 7081 81/2 digit > voltmeter shows two "thermal inertia bottles" close to the instument. > These provide a thermal mass that works with the insulation to reduce the > rate of temperature change at the unit. This will also filter short > duration transients. So a cardboard box with a couple of bottles of water > in it would make a good enclosure. Or just leave the beer in the cooler > :-) > > Robert G8RPI. > --- On Tue, 9/6/09, Poul-Henning Kamp wrote: > >> From: Poul-Henning Kamp >> Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature >> To: "Discussion of precise time and frequency measurement" >> >> Date: Tuesday, 9 June, 2009, 9:03 PM >> In message , >> Mark Sims writes: >> >> >I think that using a well insulated box [...] >> >> The point for timenuts is not just the thermal resistance, >> but more >> importantly the thermal *impedance*: you want to low-pass >> filter >> the thermal changes so that they all happen in the area >> where the >> PLL can cope with them. >> >> Thermal resistance is about insulation, thermal impedance >> is >> about (thermal) mass. >> >> So you significant mass and volume (like a fridge) not >> light and >> small (like a cardboard box). >> >> When metrology people really want to keep things at the >> same >> temperature, they mount them in oil-baths (for good thermal >> contact) >> in the middle of a block of aluminium, typically 2'x2'x1' >> (for >> thermal impedance) which is again insulated with 1" >> styrofoam, all >> of this mounted in a plywoodbox, set on rubber-wheels to >> get it off >> the floor (for thermal resistance). >> >> If they are really into this, they cover the plywood with >> high-quality >> (noble-) metal foil, to maximize reflectivity and minimize >> emissivity, >> so that the black-body radiation from devices and humans in >> the lab >> does not affect the temperature interface as much. >> >> Then they leave it alone for "some weeks" in their >> temperature >> controlled lab so the temperature can stabilize. >> >> At this point they may start to wonder how they can verify >> the pt100 >> temperature sensor they put in the middle of it all >> actually works >> when the temperature never changes... >> >> Poul-Henning >> >> -- >> Poul-Henning Kamp | UNIX >> since Zilog Zeus 3.20 >> phk at FreeBSD.ORG >> | TCP/IP since RFC 956 >> FreeBSD committer | BSD >> since 4.3-tahoe >> Never attribute to malice what can adequately be explained >> by incompetence. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com From electronicsandbooks at yahoo.com Wed Jun 10 20:36:20 2009 From: electronicsandbooks at yahoo.com (Electronics and Books) Date: Wed, 10 Jun 2009 13:36:20 -0700 (PDT) Subject: [time-nuts] Datron 4910 4911 Users Manual Message-ID: <870458.87943.qm@web43134.mail.sp1.yahoo.com> I have uploaded the Datron 4910/4911 Users Manual to www.ko4bb.com manual website. Met vriendelijke groeten Regards ElectronicsAndBooks at Yahoo dot com http://www.ElectronicsAndBooks.tk From magnus at rubidium.dyndns.org Wed Jun 10 20:50:26 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 10 Jun 2009 22:50:26 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A301C92.40208@rubidium.dyndns.org> Lux, James P skrev: > > > On 6/10/09 1:15 AM, "Magnus Danielson" wrote: >> >> Nobody having a thermal inductive material around? That would be very >> usefull to handle temperature shifts. > > Let's see.. If heat flow (watts) is the analog of current (Amps), and delta > T is the analog of voltage, what would a thermal inductor be... It would > have to have a delta T that is proportional to the rate of change of heat > flow. A tough concept to wrap my early morning before coffee brain around.. You could ask around and see if you don't have one of those lying around. Otherwise I am sure your colleagues would find good use for it. A thin sheet of it wrapped around the birds would help thermal management. > BTW There are "thermal batteries" which contain a phase change material, > like wax, in them, but just like real batteries they're more analogous to a > capacitor. For certain temperature ranges a certain dynamic range can be made to behave inductive I guess. The tunnel diode springs to mind as a similar contradictive thing with its dynamic negative resistance. > One could synthesize a thermal inductor with an active device (e.g. A heat > pump of some sort), just as one can synthesize an inductor with a op amp and > Rs and Cs (and some externally supplied energy) Synthesis would certainly be possible, but a pure thermal inductor is scarse. :) Cheers, Magnus From gwinn at RAYTHEON.COM Wed Jun 10 21:23:43 2009 From: gwinn at RAYTHEON.COM (Joseph M Gwinn) Date: Wed, 10 Jun 2009 17:23:43 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <2010.1244617999@critter.freebsd.dk> Message-ID: time-nuts-bounces at febo.com wrote on 06/10/2009 03:13:19 AM: > In message <4A2EFC6D.4020205 at xtra.co.nz>, Bruce Griffiths writes: > > Bruce, > > >>> The thermal time constant (not the thermal impedance per se) is what > >>> matters [...] > > That is pretty much exactly the (mis-)definition of thermal impedance. > > Thermal timeconstant or thermal corner-frequency had been much > better names. > > >>> It is possible to construct an enclosure with a long thermal time > >>> constant together with relatively low thermal resistance so that the > >>> temperature of a GPSDO or similar device within the enclosure only > >>> increases by a relatively small amount. > >> > >> Nope. This is essentially a thermal low pass filter. > > Well, yes you can, but it is not very useful: > > A really huge block of metal will do that: It can transfer a lot > of heat (=low resistance), but will take a long time doing so (=high > impedance). I read somewhere the suggestion to take the cast iron block from an old automobile engine and put it in a heavy insulated wooden cabinet: ~250 Kg of iron in an insulated box. Cracked blocks are useless in an engine, and so are available in junkyards quite cheap. Joe Gwinn From jfor at quik.com Wed Jun 10 21:26:29 2009 From: jfor at quik.com (J. Forster) Date: Wed, 10 Jun 2009 14:26:29 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <7995b5e60f1e044eb01ed681a05915f0.squirrel@webmail.montana.com> References: <231420.47114.qm@web27101.mail.ukl.yahoo.com> <7995b5e60f1e044eb01ed681a05915f0.squirrel@webmail.montana.com> Message-ID: <1073.12.6.201.60.1244669189.squirrel@popacctsnew.quik.com> The one I have (make unknown, but about $20 at Walgreens, likely Chinese) has an AC power supply included. This supply makes LOADS of EMI. It deafens HF recievers across the street. -John ======== > In one of my other incarnations, radio astronomy (definitely amateur if > not downright amateurish) an automotive 12 v thermoelectric cooler was > converted by one of the group into a servoed "constant" temperature box. > Those of time persuasion might want to try that. Note the small auto > coolers can just as well be converted to a constant temperature heated box > as well. > Don From james.p.lux at jpl.nasa.gov Wed Jun 10 21:30:08 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Wed, 10 Jun 2009 14:30:08 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: <2010.1244617999@critter.freebsd.dk> Message-ID: > > I read somewhere the suggestion to take the cast iron block > from an old automobile engine and put it in a heavy insulated > wooden cabinet: ~250 Kg of iron in an insulated box. Cracked > blocks are useless in an engine, and so are available in > junkyards quite cheap. > > Joe Gwinn > At $0.10-0.20/lb scrap value, cheap means $50-100 From magnus at rubidium.dyndns.org Wed Jun 10 21:36:24 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 10 Jun 2009 23:36:24 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A302758.50504@rubidium.dyndns.org> Joseph M Gwinn skrev: > time-nuts-bounces at febo.com wrote on 06/10/2009 03:13:19 AM: > >> In message <4A2EFC6D.4020205 at xtra.co.nz>, Bruce Griffiths writes: >> >> Bruce, >> >>>>> The thermal time constant (not the thermal impedance per se) is what >>>>> matters [...] >> That is pretty much exactly the (mis-)definition of thermal impedance. >> >> Thermal timeconstant or thermal corner-frequency had been much >> better names. >> >>>>> It is possible to construct an enclosure with a long thermal time >>>>> constant together with relatively low thermal resistance so that the >>>>> temperature of a GPSDO or similar device within the enclosure only >>>>> increases by a relatively small amount. >>>> Nope. This is essentially a thermal low pass filter. >> Well, yes you can, but it is not very useful: >> >> A really huge block of metal will do that: It can transfer a lot >> of heat (=low resistance), but will take a long time doing so (=high >> impedance). > > I read somewhere the suggestion to take the cast iron block from an old > automobile engine and put it in a heavy insulated wooden cabinet: ~250 Kg > of iron in an insulated box. Cracked blocks are useless in an engine, and > so are available in junkyards quite cheap. It is still just approaching a 1 pole filter. Alternating insulation/low-capacitivity - conduction/high-capacitivity in several layers creates higher pole systems. The alternation in impedance creates impedance missmatches and we should expect reflections... Oh, an interesting experiment is to try to freeze a watermelon in a steaming hot desert. Put towels on it and poor water over it. The amount of energy needed to evaporize the water exceeds the suns heatup effect, so the watermelon cools down... down... down... a bit of non-linearity causes what may seem to be a thermal induction effect. Cheers, Magnus From jmfranke at cox.net Wed Jun 10 22:03:13 2009 From: jmfranke at cox.net (jmfranke) Date: Wed, 10 Jun 2009 18:03:13 -0400 Subject: [time-nuts] Crystal ovens References: <4A302758.50504@rubidium.dyndns.org> Message-ID: <678A471B9EFF4B719D54FFAD585AC0C1@Franke> There was an interesting paper by W. A. Morrison (made the first crystal controlled clock) in the July 1928 issue of Proceedings of The Institute of Radio Engineers, pages 976-980, entitled "Thermostat Design for Frequency Standards." The article describes a crystal oven consisting of four layers: starting at the outer wall - a layer of insulation, a heater, a distributing layer, and an attenuating layer. He described a case wherein the temperature variation is reduced by a factor of "at least 10,000 to one." Of course this was for a passive crystal versus an active oscillator. John WA4WDL From hmurray at megapathdsl.net Wed Jun 10 22:09:52 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 10 Jun 2009 15:09:52 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Message from Magnus Danielson of "Wed, 10 Jun 2009 23:36:24 +0200." <4A302758.50504@rubidium.dyndns.org> Message-ID: <20090610220953.5B7F1BCEF@ip-64-139-1-69.sjc.megapath.net> > It is still just approaching a 1 pole filter. Alternating insulation/ > low-capacitivity - conduction/high-capacitivity in several layers > creates higher pole systems. > The alternation in impedance creates impedance missmatches and we > should expect reflections... Can I get reflections without some inductance? Is there any inductance in a system of alternating layers of insulation/storage? -- These are my opinions, not necessarily my employer's. I hate spam. From richard at karlquist.com Wed Jun 10 22:16:22 2009 From: richard at karlquist.com (Rick Karlquist) Date: Wed, 10 Jun 2009 15:16:22 -0700 (PDT) Subject: [time-nuts] Crystal ovens In-Reply-To: <678A471B9EFF4B719D54FFAD585AC0C1@Franke> References: <4A302758.50504@rubidium.dyndns.org> <678A471B9EFF4B719D54FFAD585AC0C1@Franke> Message-ID: <769f123dfbd9e12212ed42b1bb6c981d.squirrel@webmail.sonic.net> jmfranke wrote: > There was an interesting paper by W. A. Morrison (made the first crystal > controlled clock) in the July 1928 issue of Proceedings of The Institute > of > Radio Engineers, pages 976-980, entitled "Thermostat Design for Frequency > Standards." > The article describes a crystal oven consisting of four layers: starting > at > the outer wall - a layer of insulation, a heater, a distributing layer, > and > an attenuating layer. He described a case wherein the temperature > variation > is reduced by a factor of "at least 10,000 to one." > > Of course this was for a passive crystal versus an active oscillator. > > John WA4WDL > "10,000 to one" (thermal gain = 10,000) is very good. We could not achieve that until we applied the techiques in the following reference: http://www.karlquist.com/oven.pdf We eventually demonstated thermal gain of over a million. Again, for just a crystal. Rick Karlquist N6RK From phk at phk.freebsd.dk Wed Jun 10 22:25:11 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Wed, 10 Jun 2009 22:25:11 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Wed, 10 Jun 2009 15:09:52 MST." <20090610220953.5B7F1BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <55599.1244672711@critter.freebsd.dk> In message <20090610220953.5B7F1BCEF at ip-64-139-1-69.sjc.megapath.net>, Hal Murr ay writes: > >> It is still just approaching a 1 pole filter. Alternating insulation/ >> low-capacitivity - conduction/high-capacitivity in several layers >> creates higher pole systems. > >> The alternation in impedance creates impedance missmatches and we >> should expect reflections... > >Can I get reflections without some inductance? > >Is there any inductance in a system of alternating layers of >insulation/storage? I think you are overstretching the badly chosen nomenclatures parallels to electricity. Think of "thermal impedance" as "thermal inertia" and you get a much better picture... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From bruce.griffiths at xtra.co.nz Wed Jun 10 22:30:20 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 11 Jun 2009 10:30:20 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <20090610220953.5B7F1BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090610220953.5B7F1BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A3033FC.6070806@xtra.co.nz> Hal Murray wrote: >> It is still just approaching a 1 pole filter. Alternating insulation/ >> low-capacitivity - conduction/high-capacitivity in several layers >> creates higher pole systems. >> > > >> The alternation in impedance creates impedance missmatches and we >> should expect reflections... >> > > Can I get reflections without some inductance? > > Is there any inductance in a system of alternating layers of > insulation/storage? > > > Thermal wave reflection at boundaries/interfaces does occur: http://www.informaworld.com/smpp/content~content=a908802890~db=all~jumptype=rss http://adsabs.harvard.edu/abs/2003RScI...74..430S http://cat.inist.fr/?aModele=afficheN&cpsidt=13631768 http://soil.scijournals.org/cgi/reprint/64/4/1219 Bruce From phk at phk.freebsd.dk Wed Jun 10 22:42:33 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Wed, 10 Jun 2009 22:42:33 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Thu, 11 Jun 2009 10:30:20 +1200." <4A3033FC.6070806@xtra.co.nz> Message-ID: <55714.1244673753@critter.freebsd.dk> In message <4A3033FC.6070806 at xtra.co.nz>, Bruce Griffiths writes: >Hal Murray wrote: >Thermal wave reflection at boundaries/interfaces does occur: If your frequency or voltage standard is in a physical environment where these effects are relevant, you have much bigger problems to deal with before thermal reflection becomes your number one priority :-) Lets stay real here. Summary: For PLL steered devices, you want your device enclosed by a thermal mass which is again enclosed by a layer of thermal isolation. The goal is to filter/average all rapid (daily ?) external temperature influences, only letting through such slow variations (seasonal ?) which the PLL can comfortably cope with. Even if you use active temperature control, peltier or otherwise, it is still a good idea to employ a thermal mass to cope gracefully with power-failuers and other equipment glitches. Poul-Henning PS: The thermal mass need not be solid blocks of metal, regular ceramic bricks or tiles work fine. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From cfharris at erols.com Wed Jun 10 23:23:56 2009 From: cfharris at erols.com (Chuck Harris) Date: Wed, 10 Jun 2009 19:23:56 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A30408C.5060608@erols.com> Joseph M Gwinn wrote: > I read somewhere the suggestion to take the cast iron block from an old > automobile engine and put it in a heavy insulated wooden cabinet: ~250 Kg > of iron in an insulated box. Cracked blocks are useless in an engine, and > so are available in junkyards quite cheap. Yes, but water is so much easier to find, and easier to package, plus it has a great storage capability. -Chuck Harris From gwinn at raytheon.com Wed Jun 10 23:28:21 2009 From: gwinn at raytheon.com (Joseph M Gwinn) Date: Wed, 10 Jun 2009 19:28:21 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A30408C.5060608@erols.com> Message-ID: time-nuts-bounces at febo.com wrote on 06/10/2009 07:23:56 PM: > Joseph M Gwinn wrote: > > > I read somewhere the suggestion to take the cast iron block > from an old > > automobile engine and put it in a heavy insulated wooden > cabinet: ~250 Kg > > of iron in an insulated box. Cracked blocks are useless in > an engine, and > > so are available in junkyards quite cheap. > > Yes, but water is so much easier to find, and easier to > package, plus it has a great storage capability. And evaporates and leaks. But yes, I've used water for quick jobs. Joe Gwinn From bruce.griffiths at xtra.co.nz Wed Jun 10 23:32:50 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 11 Jun 2009 11:32:50 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A30408C.5060608@erols.com> References: <4A30408C.5060608@erols.com> Message-ID: <4A3042A2.3030104@xtra.co.nz> Chuck Harris wrote: > Joseph M Gwinn wrote: > >> I read somewhere the suggestion to take the cast iron block from an >> old automobile engine and put it in a heavy insulated wooden cabinet: >> ~250 Kg of iron in an insulated box. Cracked blocks are useless in >> an engine, and so are available in junkyards quite cheap. > > Yes, but water is so much easier to find, and easier to > package, plus it has a great storage capability. > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > The thermal conductivity of cast iron is relatively poor for a metal. Water has even lower thermal conductivity however this can be overcome by stirring. Bruce From cfharris at erols.com Wed Jun 10 23:38:49 2009 From: cfharris at erols.com (Chuck Harris) Date: Wed, 10 Jun 2009 19:38:49 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A302758.50504@rubidium.dyndns.org> References: <4A302758.50504@rubidium.dyndns.org> Message-ID: <4A304409.1060005@erols.com> Magnus Danielson wrote: > Oh, an interesting experiment is to try to freeze a watermelon in a > steaming hot desert. Put towels on it and poor water over it. The amount > of energy needed to evaporize the water exceeds the suns heatup effect, > so the watermelon cools down... down... down... a bit of non-linearity > causes what may seem to be a thermal induction effect. I've tried that very experiment on a 118F night in the Mojave Desert using me, and a wet tee-shirt, and I can say with certainty, that I didn't freeze! That was without the Sun. The Sun adds approximately 1000W/sq-meter. -Chuck Harris From holrum at hotmail.com Wed Jun 10 23:40:07 2009 From: holrum at hotmail.com (Mark Sims) Date: Wed, 10 Jun 2009 23:40:07 +0000 Subject: [time-nuts] An improved home for your Thunderbolt In-Reply-To: References: Message-ID: I did another test on my Thunderbolt isolation unit. I took my corrugated cardboard box (which measures 12x10x7" and covered it with aluminum foil. The Thunderbolt itself sits on a 1.5" thick piece of waffled foam rubber in the box. The new housing is producing results very comparable to the fully insulated box, except the internal electronics temperature is 5 degrees C less: RMS PPS error: 2.65 ns (over a two hour period) RMS OSC error 0.026 ppb Temp fluctuation: _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From cfharris at erols.com Wed Jun 10 23:45:02 2009 From: cfharris at erols.com (Chuck Harris) Date: Wed, 10 Jun 2009 19:45:02 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A30457E.9060701@erols.com> Joseph M Gwinn wrote: ... >> Yes, but water is so much easier to find, and easier to >> package, plus it has a great storage capability. > > And evaporates and leaks. But yes, I've used water for quick jobs. I just don't know what to say to that! Even a child can put a case of bottled water in a box, and not have it evaporate or leak. I would venture that said case of bottled water will still be full up when the child graduates from college, and has kids of his own. -Chuck Harris From james.p.lux at jpl.nasa.gov Thu Jun 11 00:07:00 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Wed, 10 Jun 2009 17:07:00 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: Vintage port is more traditional substance... -----Original Message----- From: "Chuck Harris" To: "Discussion of precise time and frequency measurement" Sent: 6/10/09 16:45 Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature Joseph M Gwinn wrote: ... >> Yes, but water is so much easier to find, and easier to >> package, plus it has a great storage capability. > > And evaporates and leaks. But yes, I've used water for quick jobs. I just don't know what to say to that! Even a child can put a case of bottled water in a box, and not have it evaporate or leak. I would venture that said case of bottled water will still be full up when the child graduates from college, and has kids of his own. -Chuck Harris _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From jfor at quik.com Thu Jun 11 00:14:14 2009 From: jfor at quik.com (J. Forster) Date: Wed, 10 Jun 2009 17:14:14 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A30408C.5060608@erols.com> References: <4A30408C.5060608@erols.com> Message-ID: <1375.12.6.201.70.1244679254.squirrel@popacctsnew.quik.com> Yeah, but... water can leak and make a real mess or evaporate over time and rust things or ... Maybe if it were in a chemically inert, glass container? Why not use a brick or some clean rocks or a few pounds of old nuts and bolts. -John ============ > Joseph M Gwinn wrote: > >> I read somewhere the suggestion to take the cast iron block from an old >> automobile engine and put it in a heavy insulated wooden cabinet: ~250 >> Kg >> of iron in an insulated box. Cracked blocks are useless in an engine, >> and >> so are available in junkyards quite cheap. > > Yes, but water is so much easier to find, and easier to > package, plus it has a great storage capability. > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From jfor at quik.com Thu Jun 11 00:19:00 2009 From: jfor at quik.com (J. Forster) Date: Wed, 10 Jun 2009 17:19:00 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A3042A2.3030104@xtra.co.nz> References: <4A30408C.5060608@erols.com> <4A3042A2.3030104@xtra.co.nz> Message-ID: <1395.12.6.201.70.1244679540.squirrel@popacctsnew.quik.com> Take a look here: http://en.wikipedia.org/wiki/Thermal_diffusivity -John =========== > The thermal conductivity of cast iron is relatively poor for a metal. > Water has even lower thermal conductivity however this can be overcome > by stirring. > > Bruce From lists at cq.nu Thu Jun 11 00:24:35 2009 From: lists at cq.nu (Bob Camp) Date: Wed, 10 Jun 2009 20:24:35 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1395.12.6.201.70.1244679540.squirrel@popacctsnew.quik.com> References: <4A30408C.5060608@erols.com> <4A3042A2.3030104@xtra.co.nz> <1395.12.6.201.70.1244679540.squirrel@popacctsnew.quik.com> Message-ID: Hi Just for reference: It takes about 700 pounds of steel shot to fill up the region between a 30 gallon steel drum and a 55 gallon steel drum. You can get roughly 2" of foam in between the outside of the 55 gallon steel drum and a 110 gallon drum. A 2x4 wall around the 110 gallon drum can be useful for taking care of drafts. Steel may not be perfect, but in shot form - it's cheap. Bob On Jun 10, 2009, at 8:19 PM, J. Forster wrote: > Take a look here: > > http://en.wikipedia.org/wiki/Thermal_diffusivity > > -John > > =========== > >> The thermal conductivity of cast iron is relatively poor for a metal. >> Water has even lower thermal conductivity however this can be >> overcome >> by stirring. >> >> Bruce > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From jfor at quik.com Thu Jun 11 00:30:35 2009 From: jfor at quik.com (J. Forster) Date: Wed, 10 Jun 2009 17:30:35 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A30457E.9060701@erols.com> References: <4A30457E.9060701@erols.com> Message-ID: <1421.12.6.201.70.1244680235.squirrel@popacctsnew.quik.com> Actually, Chuck, I beg to differ. I have some old bottles filled with essentially water, and the sides are now somewhat squished in, but the bottles are still sealed. There is a partial pressure differential of H2O across the plastic and H2O molecules can diffuse down that gradient. The effect may well be smaller with newer plastics. -John ======== >> And evaporates and leaks. But yes, I've used water for quick jobs. > > I just don't know what to say to that! Even a child can put a > case of bottled water in a box, and not have it evaporate or leak. > I would venture that said case of bottled water will still be full > up when the child graduates from college, and has kids of his own. > > -Chuck Harris From cfharris at erols.com Thu Jun 11 00:40:51 2009 From: cfharris at erols.com (Chuck Harris) Date: Wed, 10 Jun 2009 20:40:51 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1421.12.6.201.70.1244680235.squirrel@popacctsnew.quik.com> References: <4A30457E.9060701@erols.com> <1421.12.6.201.70.1244680235.squirrel@popacctsnew.quik.com> Message-ID: <4A305293.50901@erols.com> That's fine, but how long did it take for your bottles to get that way? My response was to a poster that complained about how hard it was to keep water from evaporating and leaking. I have a case of water that I put aside for emergencies, and it is several years old, and appears none the worse for the wear. In my mother's basement is some old canning jars full of essentially water, and they have been there for at least 30 years, still full up, still under vacuum. (Should go in the garbage, none the less.) My suggestion of a case of bottled water was to show how trivial it is for the average Joe to hold water in a bottle without leaks and other obnoxious behavior for long periods of time, with no effort. -Chuck Harris J. Forster wrote: > Actually, Chuck, I beg to differ. I have some old bottles filled with > essentially water, and the sides are now somewhat squished in, but the > bottles are still sealed. There is a partial pressure differential of H2O > across the plastic and H2O molecules can diffuse down that gradient. The > effect may well be smaller with newer plastics. > > -John > > ======== > >>> And evaporates and leaks. But yes, I've used water for quick jobs. >> I just don't know what to say to that! Even a child can put a >> case of bottled water in a box, and not have it evaporate or leak. >> I would venture that said case of bottled water will still be full >> up when the child graduates from college, and has kids of his own. >> >> -Chuck Harris > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From hmurray at megapathdsl.net Thu Jun 11 02:09:26 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 10 Jun 2009 19:09:26 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Message from "Poul-Henning Kamp" of "Wed, 10 Jun 2009 22:25:11 -0000." <55599.1244672711@critter.freebsd.dk> Message-ID: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> phk at phk.freebsd.dk said: >> Can I get reflections without some inductance? >> Is there any inductance in a system of alternating >> layers of insulation/storage? > I think you are overstretching the badly chosen nomenclatures > parallels to electricity. It was actually a (somewhat?) serious question on several grounds. Can I get reflections from a lumped circuit model of a transmission line made out of just Rs and Cs? If so, I can probably do the same in the thermal world. Can I get reflections in a thermal context? Bruce's URLs say yes, but my math is rusty enough that I can't quickly understand what's going on. If a thermal problem can generate reflections, does that mean it also has something corresponding to inductance? If so, what is it? It's possible that the key idea is time-delay. In the electrical world, a delay is a transmission line which has both C and L. I'm not sure what the one-dimensional equivalent in the thermal world is. What's the speed-of-light equivalent in the thermal world? -- These are my opinions, not necessarily my employer's. I hate spam. From bruce.griffiths at xtra.co.nz Thu Jun 11 03:00:37 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 11 Jun 2009 15:00:37 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A307355.3080600@xtra.co.nz> Hal Murray wrote: > phk at phk.freebsd.dk said: > >>> Can I get reflections without some inductance? >>> Is there any inductance in a system of alternating >>> layers of insulation/storage? >>> > > >> I think you are overstretching the badly chosen nomenclatures >> parallels to electricity. >> > > It was actually a (somewhat?) serious question on several grounds. > > Can I get reflections from a lumped circuit model of a transmission line made > out of just Rs and Cs? If so, I can probably do the same in the thermal > world. > > Can I get reflections in a thermal context? Bruce's URLs say yes, but my > math is rusty enough that I can't quickly understand what's going on. > > If a thermal problem can generate reflections, does that mean it also has > something corresponding to inductance? If so, what is it? > > It's possible that the key idea is time-delay. In the electrical world, a > delay is a transmission line which has both C and L. I'm not sure what the > one-dimensional equivalent in the thermal world is. > > What's the speed-of-light equivalent in the thermal world? > > > > > > Hal Thermal wave group velocity = 2*SQRT(4*PI*(thermal diffusivity)/(thermal wave period)). for a derivation see: http://books.google.co.nz/books?id=qSyAKzgwedIC&pg=PA153&lpg=PA153&dq=thermal+wave+velocity+diffusivity&source=bl&ots=95aUo2w5Ho&sig=t5seHCNo7H_RacyFUPcn6NFS2q0&hl=en&ei=DG0wSo-zGZ2MtgPX79C-Aw&sa=X&oi=book_result&ct=result&resnum=8#PPA153,M1 pages 153 -154 Note there is dispersion - the propagation velocity depends on the period of the thermal wave. Bruce From bruce.griffiths at xtra.co.nz Thu Jun 11 03:45:19 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 11 Jun 2009 15:45:19 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A307DCF.9010709@xtra.co.nz> Hal Murray wrote: > phk at phk.freebsd.dk said: > >>> Can I get reflections without some inductance? >>> Is there any inductance in a system of alternating >>> layers of insulation/storage? >>> > > >> I think you are overstretching the badly chosen nomenclatures >> parallels to electricity. >> > > It was actually a (somewhat?) serious question on several grounds. > > Can I get reflections from a lumped circuit model of a transmission line made > out of just Rs and Cs? If so, I can probably do the same in the thermal > world. > > Can I get reflections in a thermal context? Bruce's URLs say yes, but my > math is rusty enough that I can't quickly understand what's going on. > > If a thermal problem can generate reflections, does that mean it also has > something corresponding to inductance? If so, what is it? > > It's possible that the key idea is time-delay. In the electrical world, a > delay is a transmission line which has both C and L. I'm not sure what the > one-dimensional equivalent in the thermal world is. > > What's the speed-of-light equivalent in the thermal world? > > > > > > When heat transport via convection occurs there may be something akin to thermal inductance: Thermal mutual inductance: http://www.nature.com/nature/journal/v161/n4083/abs/161166a0.html Thermal inductance: http://adsabs.harvard.edu/full/1963AuJPh..16..353B The term thermal inductnace also occurs in Tokamak literature as well as in the the application of Josephson Junctions. However the meaning differs from the convection case. Bruce From ch at murgatroid.com Thu Jun 11 04:25:37 2009 From: ch at murgatroid.com (christopher hoover) Date: Wed, 10 Jun 2009 21:25:37 -0700 Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 MHz from 1 PPS GPS Signal Message-ID: <4A308741.7000503@murgatroid.com> [fyi -- this may be of general interest, but n.b. that this A.D. marketing - ch] Clock IC Generates Up to 400 MHz from 1 PPS GPS Signal The AD9548 is the first clock chip in the industry to directly generate up to a 400 MHz output clock, with extremely low phase noise, that is locked to a standard one pulse-per-second (PPS) GPS clock signal. This performance is a result of combining Analog Devices' proprietary direct digital synthesis (DDS) technology with a state-of-the-art digital phase-locked loop (DPLL). Other solutions for synchronizing to the GPS 1 PPS source typically rely on one or more frequency upconversion steps. Maintaining low output noise, while providing over eight orders of magnitude of frequency scaling (1 Hz input to over 100 MHz output), is a significant challenge. The AD9548 is able to mitigate this effect thanks to a digital loop filter capable of bandwidths as low as 1 MHz (10 Hz to 3 Hz). / / From m0ycm at veenstras.com Thu Jun 11 05:32:02 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Thu, 11 Jun 2009 06:32:02 +0100 Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 MHz from 1 PPSGPS Signal In-Reply-To: <4A308741.7000503@murgatroid.com> References: <4A308741.7000503@murgatroid.com> Message-ID: <13A7D8AA927244859F14FAC9A76592D9@hp> Sync to 1 pps but will not discipline the frequency source Lester B Veenstra M?YCM K1YCM lester at veenstras.com m0ycm at veenstras.com k1ycm at veenstras.com US Postal Address: PSC 45 Box 781 APO AE 09468 USA UK Postal Address: Dawn Cottage Norwood, Harrogate HG3 1SD, UK Telephones: Office: +44-(0)1423-846-385 Home: +44-(0)1943-880-963 Guam Cell: +1-671-788-5654 UK Cell: +44-(0)7716-298-224 US Cell: +1-240-425-7335 Jamaica: +1-876-352-7504 This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of christopher hoover Sent: Thursday, June 11, 2009 5:26 AM To: time-nuts at febo.com Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 MHz from 1 PPSGPS Signal [fyi -- this may be of general interest, but n.b. that this A.D. marketing - ch] Clock IC Generates Up to 400 MHz from 1 PPS GPS Signal The AD9548 is the first clock chip in the industry to directly generate up to a 400 MHz output clock, with extremely low phase noise, that is locked to a standard one pulse-per-second (PPS) GPS clock signal. This performance is a result of combining Analog Devices' proprietary direct digital synthesis (DDS) technology with a state-of-the-art digital phase-locked loop (DPLL). Other solutions for synchronizing to the GPS 1 PPS source typically rely on one or more frequency upconversion steps. Maintaining low output noise, while providing over eight orders of magnitude of frequency scaling (1 Hz input to over 100 MHz output), is a significant challenge. The AD9548 is able to mitigate this effect thanks to a digital loop filter capable of bandwidths as low as 1 MHz (10 Hz to 3 Hz). / / _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From bruce.griffiths at xtra.co.nz Thu Jun 11 05:41:49 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 11 Jun 2009 17:41:49 +1200 Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 MHz from 1 PPSGPS Signal In-Reply-To: <13A7D8AA927244859F14FAC9A76592D9@hp> References: <4A308741.7000503@murgatroid.com> <13A7D8AA927244859F14FAC9A76592D9@hp> Message-ID: <4A30991D.4060006@xtra.co.nz> However it does discipline the DDS outputs as intended. It is somewhat akin to Ulrich's approach perhaps without the robust outlier rejection. This approach would allow a wide range of relatively stable low noise sources to be used including those that may have drifted out of adjustment range. One drawback for some applications is the relatively high phase noise floor. Bruce Lester Veenstra wrote: > Sync to 1 pps but will not discipline the frequency source > > > Lester B Veenstra M?YCM K1YCM > lester at veenstras.com > m0ycm at veenstras.com > k1ycm at veenstras.com > > > US Postal Address: > PSC 45 Box 781 > APO AE 09468 USA > > UK Postal Address: > Dawn Cottage > Norwood, Harrogate > HG3 1SD, UK > > Telephones: > Office: +44-(0)1423-846-385 > Home: +44-(0)1943-880-963 > Guam Cell: +1-671-788-5654 > UK Cell: +44-(0)7716-298-224 > US Cell: +1-240-425-7335 > Jamaica: +1-876-352-7504 > > This e-mail and any documents attached hereto contain confidential or > privileged information. The information is intended to be for use only by > the individual or entity to whom they are addressed. If you are not the > intended recipient or the person responsible for delivering the e-mail to > the intended recipient, be aware that any disclosure, copying, distribution > or use of the contents of this e-mail or any documents attached hereto is > prohibited. > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of christopher hoover > Sent: Thursday, June 11, 2009 5:26 AM > To: time-nuts at febo.com > Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 MHz from 1 PPSGPS > Signal > > > [fyi -- this may be of general interest, but n.b. that this A.D. > marketing - ch] > > > Clock IC Generates Up to 400 MHz from 1 PPS GPS Signal > > The AD9548 > /ad9548/products/product.html> > is the first clock chip in the industry to directly generate up to a 400 > MHz output clock, with extremely low phase noise, that is locked to a > standard one pulse-per-second (PPS) GPS clock signal. This performance > is a result of combining Analog Devices' proprietary direct digital > synthesis (DDS) technology with a state-of-the-art digital phase-locked > loop (DPLL). Other solutions for synchronizing to the GPS 1 PPS source > typically rely on one or more frequency upconversion steps. Maintaining > low output noise, while providing over eight orders of magnitude of > frequency scaling (1 Hz input to over 100 MHz output), is a significant > challenge. The AD9548 is able to mitigate this effect thanks to a > digital loop filter capable of bandwidths as low as 1 MHz (10 Hz to 3 Hz). > > > / > / > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From rexa at sonic.net Thu Jun 11 05:50:40 2009 From: rexa at sonic.net (Rex) Date: Wed, 10 Jun 2009 22:50:40 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A309B30.7000400@sonic.net> Hal Murray wrote: >phk at phk.freebsd.dk said: > > >>>Can I get reflections without some inductance? >>>Is there any inductance in a system of alternating >>>layers of insulation/storage? >>> >>> > > > >>I think you are overstretching the badly chosen nomenclatures >>parallels to electricity. >> >> > >It was actually a (somewhat?) serious question on several grounds. > >Can I get reflections from a lumped circuit model of a transmission line made >out of just Rs and Cs? If so, I can probably do the same in the thermal >world. > >Can I get reflections in a thermal context? Bruce's URLs say yes, but my >math is rusty enough that I can't quickly understand what's going on. > >If a thermal problem can generate reflections, does that mean it also has >something corresponding to inductance? If so, what is it? > >It's possible that the key idea is time-delay. In the electrical world, a >delay is a transmission line which has both C and L. I'm not sure what the >one-dimensional equivalent in the thermal world is. > >What's the speed-of-light equivalent in the thermal world? > > > > > Why were you somewhat serious about this? If you want to extropolate heat into electromagnestic waves, what would be the analog of frequency? There are a few parallels in the two realms by analogy but that doesn't mean they map in all aspects. Sometimes, to help learning ohms law, the analogy of water is used with pressure = voltage, flow = current, resistance = narrow pipes. It sort of makes the concepts easier to grasp, but when you get to AC and wave reflections I think one has to struggle to make the water analogy useful. For heat, I think the water analog might be more useful than trying to map the EM waves to heat. The reflection idea did remind me of something that occurred to me, a gallows-humor joke from years back. I'm sure most of you remember hearing about the 1989 San Francisco earthquake. The earthquake epicenter was between Santa Cruz and San Jose, about 40 miles south of San Francisco, but a lot of the serious damage and fires occurred in San Francisco near the tip of the penninsula at the bay shore. There was a lot of discussion about this localized damage so far away, and how that could happen. San Francisco is at the tip of a peninsula that forms the Bay. I immediately thought that the problem was obvious. The penninsula was excited at its bottom end and was left improperly terminated at San Francisco. I couldn't tell this joke for two reasons, one: it was in bad taste, but two: I only knew a few people who would get it -- the mismatch/termination joke. Now, back to the subject of heat, I have a strange observation that I posted on the web a few years ago. A few people thought they had seen the same thing, but most thought what I noticed was not real. I posted because, if it was true, it seemed unexpected and I had never heard anything that could explain it. I was welding or heat treating steel. Imagine a steel bar about 1 inch (2.54 cm) in diameter and a foot to 18 " (30-40 cm) long. The bar is clamped in a vise and with a torch one end is quickly brought up to red heat. The other end is still cool enough that with my bare hand I can hold the bar by the cool end and carry it into the next room. I carry it there to cool it in the sink. A stream of cold water turned on, I quickly cool the hot end in the water. My observation, from doing this several times, is that the cold water quickly absorbes heat from the red end, but also seems to chase a lot of the heat quickly up toward the cold end, making the bar rapidly uncomfortable to hold. So that's my observation. I think the sudden cooling of the very hot end has somehow chased a glob of heat toward the cool end. If true, I have no explanation. I don't think it is related to steam; it seems to me to be something happening inside the bar. Most people thought it was coincidence of heat propagating up the bar just at that time, or steam. Could be, but I still think it is real. The cold end of the bar was slowly getting warmer as I carried it, but after the sudden cooling of the hot end, the cold end seemed to get hot fast. I meant to try an experiment with two bars and dual thermocouples, but I never got around to it. The main problem is getting things close enough to compare without questioning the heated states. My plan would have been: attach two themocouples to the cold end of two identical bars. Heat the two other ends rapidly to red heat (that is the very hard part to get right and balanced) and then just cool one bar rapidly while recording both temp profiles of the cold ends. If I figure out how to do the heating quick and balanced, I may still try the experiment. So I started with a bit of complaining about the rambling of the thread, and now I've rambled it in a whole nother direction. Sorry, I guess. From bruce.griffiths at xtra.co.nz Thu Jun 11 05:57:31 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 11 Jun 2009 17:57:31 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A309B30.7000400@sonic.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> Message-ID: <4A309CCB.6020009@xtra.co.nz> Rex wrote: > Hal Murray wrote: > >> phk at phk.freebsd.dk said: >> >> >>>> Can I get reflections without some inductance? >>>> Is there any inductance in a system of alternating >>>> layers of insulation/storage? >>>> >> >> >> >>> I think you are overstretching the badly chosen nomenclatures >>> parallels to electricity. >> >> It was actually a (somewhat?) serious question on several grounds. >> >> Can I get reflections from a lumped circuit model of a transmission >> line made out of just Rs and Cs? If so, I can probably do the same >> in the thermal world. >> >> Can I get reflections in a thermal context? Bruce's URLs say yes, >> but my math is rusty enough that I can't quickly understand what's >> going on. >> >> If a thermal problem can generate reflections, does that mean it also >> has something corresponding to inductance? If so, what is it? >> >> It's possible that the key idea is time-delay. In the electrical >> world, a delay is a transmission line which has both C and L. I'm >> not sure what the one-dimensional equivalent in the thermal world is. >> >> What's the speed-of-light equivalent in the thermal world? >> >> >> >> >> > > Why were you somewhat serious about this? > > If you want to extropolate heat into electromagnestic waves, what > would be the analog of frequency? There are a few parallels in the two > realms by analogy but that doesn't mean they map in all aspects. > Sometimes, to help learning ohms law, the analogy of water is used > with pressure = voltage, flow = current, resistance = narrow pipes. It > sort of makes the concepts easier to grasp, but when you get to AC and > wave reflections I think one has to struggle to make the water analogy > useful. For heat, I think the water analog might be more useful than > trying to map the EM waves to heat. > > The reflection idea did remind me of something that occurred to me, a > gallows-humor joke from years back. I'm sure most of you remember > hearing about the 1989 San Francisco earthquake. The earthquake > epicenter was between Santa Cruz and San Jose, about 40 miles south of > San Francisco, but a lot of the serious damage and fires occurred in > San Francisco near the tip of the penninsula at the bay shore. There > was a lot of discussion about this localized damage so far away, and > how that could happen. San Francisco is at the tip of a peninsula that > forms the Bay. I immediately thought that the problem was obvious. The > penninsula was excited at its bottom end and was left improperly > terminated at San Francisco. I couldn't tell this joke for two > reasons, one: it was in bad taste, but two: I only knew a few people > who would get it -- the mismatch/termination joke. > > Now, back to the subject of heat, I have a strange observation that I > posted on the web a few years ago. A few people thought they had seen > the same thing, but most thought what I noticed was not real. I posted > because, if it was true, it seemed unexpected and I had never heard > anything that could explain it. > > I was welding or heat treating steel. Imagine a steel bar about 1 inch > (2.54 cm) in diameter and a foot to 18 " (30-40 cm) long. The bar is > clamped in a vise and with a torch one end is quickly brought up to > red heat. The other end is still cool enough that with my bare hand I > can hold the bar by the cool end and carry it into the next room. I > carry it there to cool it in the sink. A stream of cold water turned > on, I quickly cool the hot end in the water. My observation, from > doing this several times, is that the cold water quickly absorbes heat > from the red end, but also seems to chase a lot of the heat quickly up > toward the cold end, making the bar rapidly uncomfortable to hold. So > that's my observation. I think the sudden cooling of the very hot end > has somehow chased a glob of heat toward the cool end. If true, I have > no explanation. I don't think it is related to steam; it seems to me > to be something happening inside the bar. > > Most people thought it was coincidence of heat propagating up the bar > just at that time, or steam. Could be, but I still think it is real. > The cold end of the bar was slowly getting warmer as I carried it, but > after the sudden cooling of the hot end, the cold end seemed to get > hot fast. > > I meant to try an experiment with two bars and dual thermocouples, but > I never got around to it. The main problem is getting things close > enough to compare without questioning the heated states. My plan would > have been: attach two themocouples to the cold end of two identical > bars. Heat the two other ends rapidly to red heat (that is the very > hard part to get right and balanced) and then just cool one bar > rapidly while recording both temp profiles of the cold ends. If I > figure out how to do the heating quick and balanced, I may still try > the experiment. > > So I started with a bit of complaining about the rambling of the > thread, and now I've rambled it in a whole nother direction. Sorry, I > guess. > > > > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Rex your experience with the hot bar is quite common. Bruce From rexa at sonic.net Thu Jun 11 06:21:42 2009 From: rexa at sonic.net (Rex) Date: Wed, 10 Jun 2009 23:21:42 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A309CCB.6020009@xtra.co.nz> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <4A309CCB.6020009@xtra.co.nz> Message-ID: <4A30A276.8090806@sonic.net> Bruce Griffiths wrote: >Rex wrote: > > >>Now, back to the subject of heat, I have a strange observation that I >>posted on the web a few years ago. A few people thought they had seen >>the same thing, but most thought what I noticed was not real. I posted >>because, if it was true, it seemed unexpected and I had never heard >>anything that could explain it. >> >>I was welding or heat treating steel. Imagine a steel bar about 1 inch >>(2.54 cm) in diameter and a foot to 18 " (30-40 cm) long. The bar is >>clamped in a vise and with a torch one end is quickly brought up to >>red heat. The other end is still cool enough that with my bare hand I >>can hold the bar by the cool end and carry it into the next room. I >>carry it there to cool it in the sink. A stream of cold water turned >>on, I quickly cool the hot end in the water. My observation, from >>doing this several times, is that the cold water quickly absorbes heat >>from the red end, but also seems to chase a lot of the heat quickly up >>toward the cold end, making the bar rapidly uncomfortable to hold. So >>that's my observation. I think the sudden cooling of the very hot end >>has somehow chased a glob of heat toward the cool end. If true, I have >>no explanation. I don't think it is related to steam; it seems to me >>to be something happening inside the bar. >> >>Most people thought it was coincidence of heat propagating up the bar >>just at that time, or steam. Could be, but I still think it is real. >>The cold end of the bar was slowly getting warmer as I carried it, but >>after the sudden cooling of the hot end, the cold end seemed to get >>hot fast. >> >>I meant to try an experiment with two bars and dual thermocouples, but >>I never got around to it. The main problem is getting things close >>enough to compare without questioning the heated states. My plan would >>have been: attach two themocouples to the cold end of two identical >>bars. Heat the two other ends rapidly to red heat (that is the very >>hard part to get right and balanced) and then just cool one bar >>rapidly while recording both temp profiles of the cold ends. If I >>figure out how to do the heating quick and balanced, I may still try >>the experiment. >> >>So I started with a bit of complaining about the rambling of the >>thread, and now I've rambled it in a whole nother direction. Sorry, I >>guess. >> >> >> >> >> >Rex > >your experience with the hot bar is quite common. > >Bruce > > > > Bruce, Good to hear someone with your credentials validate my "heat-chasing" observation. I am not aware of anything in common physics that explains the phenomina. Is there some kind of thermodynamic or atomic explanation? Got any leads? -Rex From jmiles at pop.net Thu Jun 11 06:27:50 2009 From: jmiles at pop.net (John Miles) Date: Wed, 10 Jun 2009 23:27:50 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A309CCB.6020009@xtra.co.nz> Message-ID: > Rex > > your experience with the hot bar is quite common. Sounds like a pretty reasonable manifestation of the Leidenfrost effect. The water in contact with the hot end of the bar vaporizes, and the resulting steam layer (which might be microscopic) does a good job insulating the bar. There's nowhere else for the heat to radiate or conduct to, except towards the cold end of the bar. -- john, KE5FX From sar10538 at gmail.com Thu Jun 11 06:51:34 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Thu, 11 Jun 2009 18:51:34 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A30457E.9060701@erols.com> References: <4A30457E.9060701@erols.com> Message-ID: <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> 2009/6/11 Chuck Harris : > Joseph M Gwinn wrote: > ... >>> >>> Yes, but water is so much easier to find, and easier to >>> package, plus it has a great storage capability. >> >> And evaporates and leaks. ?But yes, I've used water for quick jobs. > > I just don't know what to say to that! ?Even a child can put a > case of bottled water in a box, and not have it evaporate or leak. > I would venture that said case of bottled water will still be full > up when the child graduates from college, and has kids of his own. But goodness knows what sort of a biological hazard it will be by then :-) > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From magnus at rubidium.dyndns.org Thu Jun 11 07:29:24 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Thu, 11 Jun 2009 09:29:24 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A309B30.7000400@sonic.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> Message-ID: <4A30B254.3070408@rubidium.dyndns.org> Rex skrev: > Now, back to the subject of heat, I have a strange observation that I > posted on the web a few years ago. A few people thought they had seen > the same thing, but most thought what I noticed was not real. I posted > because, if it was true, it seemed unexpected and I had never heard > anything that could explain it. > > I was welding or heat treating steel. Imagine a steel bar about 1 inch > (2.54 cm) in diameter and a foot to 18 " (30-40 cm) long. The bar is > clamped in a vise and with a torch one end is quickly brought up to red > heat. The other end is still cool enough that with my bare hand I can > hold the bar by the cool end and carry it into the next room. I carry it > there to cool it in the sink. A stream of cold water turned on, I > quickly cool the hot end in the water. My observation, from doing this > several times, is that the cold water quickly absorbes heat from the red > end, but also seems to chase a lot of the heat quickly up toward the > cold end, making the bar rapidly uncomfortable to hold. So that's my > observation. I think the sudden cooling of the very hot end has somehow > chased a glob of heat toward the cool end. If true, I have no > explanation. I don't think it is related to steam; it seems to me to be > something happening inside the bar. The propagation speed for the heat comes into play. It takes time for the heat from the hot end to reach the cold end. As we are fairly off track here, let me relay a similar story. My mother has been working with food all her professional life. A christmas tradition here in Sweden is to have big lumps of ham from which you carve slices. However, the damn thing needs to be cooked. If you do it in the oven it dries out, if you only boil it you do not get that crisp surface people want. You can do a bit of both. However, one year she thought about cooking it in the microwave oven. She has no formal training in thermodynamics and didn't really involve me in the thought process, but she figured that if she ran the microwave for half an hour, after wrapping the ham in microwave-grade plastic, just to avoid it to dry out, and then just let it sit on the bench, then it would hit those 70 degrees in the core after a while anyway. Sure thing, it did. Worked like a charm. Perfectly cooked, juicy. What happends is that it takes time for the heat-wave to reach the core, so even if she stopped providing more heat the heat-wave was still in progress and just could not be stopped. > Most people thought it was coincidence of heat propagating up the bar > just at that time, or steam. Could be, but I still think it is real. The > cold end of the bar was slowly getting warmer as I carried it, but after > the sudden cooling of the hot end, the cold end seemed to get hot fast. Yes... it would have got hot regardless of cooling or not at the hot end. Also, the heat-wave wavefront isn't a flat surface... > I meant to try an experiment with two bars and dual thermocouples, but I > never got around to it. The main problem is getting things close enough > to compare without questioning the heated states. My plan would have > been: attach two themocouples to the cold end of two identical bars. > Heat the two other ends rapidly to red heat (that is the very hard part > to get right and balanced) and then just cool one bar rapidly while > recording both temp profiles of the cold ends. If I figure out how to > do the heating quick and balanced, I may still try the experiment. That would be a neat exercise to demonstrate things... > So I started with a bit of complaining about the rambling of the thread, > and now I've rambled it in a whole nother direction. Sorry, I guess. I guess it is an interesting side topic, the food aside. Cheers, Magnus From phk at phk.freebsd.dk Thu Jun 11 07:55:21 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Thu, 11 Jun 2009 07:55:21 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Wed, 10 Jun 2009 19:45:02 -0400." <4A30457E.9060701@erols.com> Message-ID: <1976.1244706921@critter.freebsd.dk> In message <4A30457E.9060701 at erols.com>, Chuck Harris writes: >> And evaporates and leaks. But yes, I've used water for quick jobs. > >I just don't know what to say to that! Even a child can put a >case of bottled water in a box, and not have it evaporate or leak. >I would venture that said case of bottled water will still be full >up when the child graduates from college, and has kids of his own. Unless UPS or DHL decides to leave your package stranded on a loading dock in -20?C for a couple of days. In the lab I *might* use water, for shipping I never would. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From phk at phk.freebsd.dk Thu Jun 11 08:03:30 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Thu, 11 Jun 2009 08:03:30 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Wed, 10 Jun 2009 22:50:40 MST." <4A309B30.7000400@sonic.net> Message-ID: <2007.1244707410@critter.freebsd.dk> In message <4A309B30.7000400 at sonic.net>, Rex writes: >My observation, from doing this >several times, is that the cold water quickly absorbes heat from the red >end, but also seems to chase a lot of the heat quickly up toward the >cold end, making the bar rapidly uncomfortable to hold. I've seen the effect you describe explained in an article somewhere, very likely New Scientist or SciAm about five years ago. When you rapidly heat or cool metals, very often changes in crystal lattice structure is involved some of them resulting in quite drastic changes to volume. Heat is essentially atoms wiggling about, and when you change the modes of freedom for the atoms, they may have to wiggle harder. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From df6jb at ulrich-bangert.de Thu Jun 11 08:48:42 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 11 Jun 2009 10:48:42 +0200 Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 MHz from 1 PPSGPS Signal In-Reply-To: <4A30991D.4060006@xtra.co.nz> Message-ID: > However it does discipline the DDS outputs as intended. > It is somewhat akin to Ulrich's approach perhaps without the > robust outlier rejection. Surely AD has not copied from me, but yes indeed this looks similar to my approach. The output noise may by tamed by loosely coupling a high quality OCXO to the output. Perhaps one should think over a circuit that a) surpresses PPS outliers and b) applies sawtooth correction to the PPS Best regads Ulrich Bangert > -----Urspr?ngliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Bruce Griffiths > Gesendet: Donnerstag, 11. Juni 2009 07:42 > An: lester at veenstras.com; Discussion of precise time and > frequency measurement > Betreff: Re: [time-nuts] AD9548 - Clock IC Generates Up to > 400 MHz from 1 PPSGPS Signal > > > However it does discipline the DDS outputs as intended. > It is somewhat akin to Ulrich's approach perhaps without the > robust outlier rejection. This approach would allow a wide > range of relatively stable low noise sources to be used > including those that may have drifted out of adjustment > range. One drawback for some applications is the relatively > high phase noise floor. > > Bruce > > Lester Veenstra wrote: > > Sync to 1 pps but will not discipline the frequency source > > > > > > Lester B Veenstra M?YCM K1YCM > > lester at veenstras.com > > m0ycm at veenstras.com > > k1ycm at veenstras.com > > > > > > US Postal Address: > > PSC 45 Box 781 > > APO AE 09468 USA > > > > UK Postal Address: > > Dawn Cottage > > Norwood, Harrogate > > HG3 1SD, UK > > > > Telephones: > > Office: +44-(0)1423-846-385 > > Home: +44-(0)1943-880-963 > > Guam Cell: +1-671-788-5654 > > UK Cell: +44-(0)7716-298-224 > > US Cell: +1-240-425-7335 > > Jamaica: +1-876-352-7504 > > > > This e-mail and any documents attached hereto contain > confidential or > > privileged information. The information is intended to be > for use only > > by the individual or entity to whom they are addressed. If > you are not > > the intended recipient or the person responsible for delivering the > > e-mail to the intended recipient, be aware that any disclosure, > > copying, distribution or use of the contents of this e-mail or any > > documents attached hereto is prohibited. > > > > -----Original Message----- > > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] > > On Behalf Of christopher hoover > > Sent: Thursday, June 11, 2009 5:26 AM > > To: time-nuts at febo.com > > Subject: [time-nuts] AD9548 - Clock IC Generates Up to 400 > MHz from 1 > > PPSGPS Signal > > > > > > [fyi -- this may be of general interest, but n.b. that this A.D. > > marketing - ch] > > > > > > Clock IC Generates Up to 400 MHz from 1 PPS GPS Signal > > > > The AD9548 > > > /ad9548/products/product.html> > is the first clock chip in the industry to directly generate up to a 400 > MHz output clock, with extremely low phase noise, that is locked to a > standard one pulse-per-second (PPS) GPS clock signal. This performance > is a result of combining Analog Devices' proprietary direct digital > synthesis (DDS) technology with a state-of-the-art digital phase-locked > loop (DPLL). Other solutions for synchronizing to the GPS 1 PPS source > typically rely on one or more frequency upconversion steps. Maintaining > low output noise, while providing over eight orders of magnitude of > frequency scaling (1 Hz input to over 100 MHz output), is a significant > challenge. The AD9548 is able to mitigate this effect thanks to a > digital loop filter capable of bandwidths as low as 1 MHz (10 Hz to 3 Hz). > > > / > / > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From rexa at sonic.net Thu Jun 11 09:41:59 2009 From: rexa at sonic.net (Rex) Date: Thu, 11 Jun 2009 02:41:59 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A30D167.9090700@sonic.net> John Miles wrote: >>Rex >> >>your experience with the hot bar is quite common. >> >> > >Sounds like a pretty reasonable manifestation of the Leidenfrost effect. >The water in contact with the hot end of the bar vaporizes, and the >resulting steam layer (which might be microscopic) does a good job >insulating the bar. There's nowhere else for the heat to radiate or conduct >to, except towards the cold end of the bar. > >-- john, KE5FX > > > > > John, You too never cease to impress by providing bits of knowledege I've never heard about. Leidenfrost effect. My first instinct was to dismember the German word, which was a bad idea. Wiki told me about the relevant meaning. Yes, that is a possibility about what I may have observed. Let's see. I should produce the same efffect by jamming the hot end into a tight insulating hole. Shouldn't be too hard to test subjectively. My guess -- there is more than that involved. But just speculation so far. I haven't even proved my initial observation. From rexa at sonic.net Thu Jun 11 09:48:38 2009 From: rexa at sonic.net (Rex) Date: Thu, 11 Jun 2009 02:48:38 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <2007.1244707410@critter.freebsd.dk> References: <2007.1244707410@critter.freebsd.dk> Message-ID: <4A30D2F6.7070900@sonic.net> Poul-Henning Kamp wrote: >In message <4A309B30.7000400 at sonic.net>, Rex writes: > > > >>My observation, from doing this >>several times, is that the cold water quickly absorbes heat from the red >>end, but also seems to chase a lot of the heat quickly up toward the >>cold end, making the bar rapidly uncomfortable to hold. >> >> > >I've seen the effect you describe explained in an article somewhere, >very likely New Scientist or SciAm about five years ago. > >When you rapidly heat or cool metals, very often changes in crystal >lattice structure is involved some of them resulting in quite drastic >changes to volume. > >Heat is essentially atoms wiggling about, and when you change the >modes of freedom for the atoms, they may have to wiggle harder. > > > Thanks, that sounds like the most likely explanation I have heard. If you find a more complete citation, I'd be interested to hear about it. From df6jb at ulrich-bangert.de Thu Jun 11 10:46:13 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 11 Jun 2009 12:46:13 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <55714.1244673753@critter.freebsd.dk> Message-ID: > For PLL steered devices, you want your device enclosed by a > thermal mass which is again enclosed by a layer of thermal > isolation. The goal is to filter/average all rapid (daily ?) > external temperature influences, only letting through such > slow variations (seasonal ?) which the PLL can comfortably cope with. My impression with this thread is that two sligthly different things are being discussed here: Some posters explain how a crystal oven shall be designed as Poul-Henning does with his words above. Absolute correct, no doubt about it! Nevertheless only a VERY few of us (Rick for example) have real experience in designing ovens and most of us are confronted with a existent ready to go OCXOs. That is why one can start a discussion about the question whether the thermal properties of an existing OCXO can be improved which is what the second group of posters has done starting with the Thunderbolt. The situation with the ready to go OCXO is a bit different than starting from scratch: The OCXO DOES already have a certain thermal mass inside and it DOES already have a certain thermal insulation of this mass against the ambient. BOTH of these parameters have been important properties for the designer of the oven's temperature controller. The temperature controller's properties must match EXACTLY the thermal mass as well as the amount of insulation in order to work as expected. If one of you has personal experience with high precision temperature controllers I am sure he can second this claim. The situation gets the harder the better the thermal insulation is: You need to avoid every kind of regulation overshot because it is only the high insulation that allows energy to leak out of the thermal mass. Which in turn requires high regulator time constants. By the way: That is also the reason for the heat sinks on rubidium standards. They form a good coupling to the ambient (=small insulation) making the design of the lamp's temperature controller much more easy and much faster than with a good insulation. With a ready OCXO in your hand like the 10811 or the FTS1200 or anything else: You can't improve the beast by "simply better insulation" or by "simply higher thermal mass", because every change in this will have worse impacts on the action of the temperature controller. However, there ARE ways to improve the thermal behavour of an ready to go OCXO: First rule: Allow the temperature controller to "see" the original thermal mass, i.e. don't open the enclosure and don't change anything, just leave everything as it is. Second rule: Allow the temperature controller to "see" the original thermal insulation, i.e. allow for some cubic centimeters of air around the OCXO's outer enclosure. It was engineered with that surrounding in mind! Third rule: Outside of the these few cubic centimeters of air around the OCXO you are allowed ANYTHING. You can for example put a big thermal mass like a massive aluminium enclosure around the OCXO (but please don't forget the few cubic centimeters of air between this and the surface of the OCXO). THIS thermal mass in conjunction with the air around it will work as the thermal lowpass filter that some posters talked about but WITHOUT worrying the OCXO's temperature controller because it "sees" the original thermal mass and the original thermal insulation. But it "sees" smaller ambient temperature variations than before. This would be a passive solution where the aim were to get high time constants for the combination of the outer enclosure and the surrounding air making as much thermal mass as possible the prefered way. One of my 10811 resides in a 12 X 12 X 12 cm aluminium enclosure with 2 cm wall thickness. This has given a thermal time constant in the order of precious few hours if i remember correctly and was far from averaging daily temperature changes. It might however be helpful for the discussed problem of Thunderbolt reactions to short time temperature changes. Or one can decide for a active solution. This would call for an outer enclosure where not high thermal mass but high thermal conductivity were the aim which is brought to a constant temperature by means of a second temperature controller, the famous "double oven" principle if you like. As in the passive case there must be enough air between OCXO and the outer controller in order to avoid any interaction between the temperature controllers. Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp > Gesendet: Donnerstag, 11. Juni 2009 00:43 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Thunderbolt stability and ambient temperature > > > In message <4A3033FC.6070806 at xtra.co.nz>, Bruce Griffiths writes: > >Hal Murray wrote: > > >Thermal wave reflection at boundaries/interfaces does occur: > > If your frequency or voltage standard is in a physical > environment where these effects are relevant, you have much > bigger problems to deal with before thermal reflection > becomes your number one priority :-) > > Lets stay real here. > > Summary: > > For PLL steered devices, you want your device enclosed by a > thermal mass which is again enclosed by a layer of thermal > isolation. The goal is to filter/average all rapid (daily ?) > external temperature influences, only letting through such > slow variations (seasonal ?) which the PLL can comfortably cope with. > > Even if you use active temperature control, peltier or > otherwise, it is still a good idea to employ a thermal mass > to cope gracefully with power-failuers and other equipment glitches. > > Poul-Henning > > PS: The thermal mass need not be solid blocks of metal, > regular ceramic bricks or tiles work fine. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk at FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by > incompetence. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From phk at phk.freebsd.dk Thu Jun 11 10:50:10 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Thu, 11 Jun 2009 10:50:10 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Thu, 11 Jun 2009 12:46:13 +0200." Message-ID: <20994.1244717410@critter.freebsd.dk> In message , "Ulrich Bangert" writes: >> For PLL steered devices, you want your device enclosed by a >> thermal mass which is again enclosed by a layer of thermal >> isolation. The goal is to filter/average all rapid (daily ?) >> external temperature influences, only letting through such >> slow variations (seasonal ?) which the PLL can comfortably cope with. > >My impression with this thread is that two sligthly different things are >being discussed here: > >Some posters explain how a crystal oven shall be designed as Poul-Henning >does with his words above. Absolute correct, no doubt about it! I'm not talking about crystal ovens, I'm talking about timekeeping kit in general: how to filter high frequency temperature fluctuations out, so the PLL does not have to deal with them. The above advice applies to GPSDO's and Rb's and Cs's as well as TCXOs, OCXOs and voltage references. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From stijena at tapko.de Thu Jun 11 12:17:25 2009 From: stijena at tapko.de (Predrag Dukic) Date: Thu, 11 Jun 2009 14:17:25 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: <55714.1244673753@critter.freebsd.dk> Message-ID: <7.0.1.0.1.20090611140516.00a2fba0@tapko.de> I didn't try it but if You want to average daily (or even seasonal) temperature changes, one could drill the floor of a cellar ( Your time-nuts gear is in the cellar, isn't it?) with the geotechnical drill used for core samples of soil and rock . 3-4 inch diameter drills are standard, and surely make enough space for 10811. Few meters down, I expect seasonal changes 1-2 deg with 50 deg external winter-summer change. Under buildings probably even less...(permafrost story...) Plastic sewage pipe inserted in to keep water out, and You have thermal mass as much as You like. P. Dukic At 12:46 11.6.2009, you wrote: > > For PLL steered devices, you want your device enclosed by a > > thermal mass which is again enclosed by a layer of thermal > > isolation. The goal is to filter/average all rapid (daily ?) > > external temperature influences, only letting through such > > slow variations (seasonal ?) which the PLL can comfortably cope with. > >My impression with this thread is that two sligthly different things are >being discussed here: > >Some posters explain how a crystal oven shall be designed as Poul-Henning >does with his words above. Absolute correct, no doubt about it! > >Nevertheless only a VERY few of us (Rick for example) have real experience >in designing ovens and most of us are confronted with a existent ready to go >OCXOs. That is why one can start a discussion about the question whether the >thermal properties of an existing OCXO can be improved which is what the >second group of posters has done starting with the Thunderbolt. > >The situation with the ready to go OCXO is a bit different than starting >from scratch: The OCXO DOES already have a certain thermal mass inside and >it DOES already have a certain thermal insulation of this mass against the >ambient. > >BOTH of these parameters have been important properties for the designer of >the oven's temperature controller. The temperature controller's properties >must match EXACTLY the thermal mass as well as the amount of insulation in >order to work as expected. If one of you has personal experience with high >precision temperature controllers I am sure he can second this claim. The >situation gets the harder the better the thermal insulation is: You need to >avoid every kind of regulation overshot because it is only the high >insulation that allows energy to leak out of the thermal mass. Which in turn >requires high regulator time constants. > >By the way: That is also the reason for the heat sinks on rubidium >standards. They form a good coupling to the ambient (=small insulation) >making the design of the lamp's temperature controller much more easy and >much faster than with a good insulation. > >With a ready OCXO in your hand like the 10811 or the FTS1200 or anything >else: You can't improve the beast by "simply better insulation" or by >"simply higher thermal mass", because every change in this will have worse >impacts on the action of the temperature controller. > >However, there ARE ways to improve the thermal behavour of an ready to go >OCXO: > >First rule: Allow the temperature controller to "see" the original thermal >mass, i.e. don't open the enclosure and don't change anything, just leave >everything as it is. > >Second rule: Allow the temperature controller to "see" the original thermal >insulation, i.e. allow for some cubic centimeters of air around the OCXO's >outer enclosure. It was engineered with that surrounding in mind! > >Third rule: Outside of the these few cubic centimeters of air around the >OCXO you are allowed ANYTHING. > >You can for example put a big thermal mass like a massive aluminium >enclosure around the OCXO (but please don't forget the few cubic centimeters >of air between this and the surface of the OCXO). THIS thermal mass in >conjunction with the air around it will work as the thermal lowpass filter >that some posters talked about but WITHOUT worrying the OCXO's temperature >controller because it "sees" the original thermal mass and the original >thermal insulation. But it "sees" smaller ambient temperature variations >than before. > >This would be a passive solution where the aim were to get high time >constants for the combination of the outer enclosure and the surrounding air >making as much thermal mass as possible the prefered way. One of my 10811 >resides in a 12 X 12 X 12 cm aluminium enclosure with 2 cm wall thickness. >This has given a thermal time constant in the order of precious few hours if >i remember correctly and was far from averaging daily temperature changes. >It might however be helpful for the discussed problem of Thunderbolt >reactions to short time temperature changes. > >Or one can decide for a active solution. This would call for an outer >enclosure where not high thermal mass but high thermal conductivity were the >aim which is brought to a constant temperature by means of a second >temperature controller, the famous "double oven" principle if you like. As >in the passive case there must be enough air between OCXO and the outer >controller in order to avoid any interaction between the temperature >controllers. > >Best regards >Ulrich Bangert > > > > > -----Ursprungliche Nachricht----- > > Von: time-nuts-bounces at febo.com > > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp > > Gesendet: Donnerstag, 11. Juni 2009 00:43 > > An: Discussion of precise time and frequency measurement > > Betreff: Re: [time-nuts] Thunderbolt stability and ambient temperature > > > > > > In message <4A3033FC.6070806 at xtra.co.nz>, Bruce Griffiths writes: > > >Hal Murray wrote: > > > > >Thermal wave reflection at boundaries/interfaces does occur: > > > > If your frequency or voltage standard is in a physical > > environment where these effects are relevant, you have much > > bigger problems to deal with before thermal reflection > > becomes your number one priority :-) > > > > Lets stay real here. > > > > Summary: > > > > For PLL steered devices, you want your device enclosed by a > > thermal mass which is again enclosed by a layer of thermal > > isolation. The goal is to filter/average all rapid (daily ?) > > external temperature influences, only letting through such > > slow variations (seasonal ?) which the PLL can comfortably cope with. > > > > Even if you use active temperature control, peltier or > > otherwise, it is still a good idea to employ a thermal mass > > to cope gracefully with power-failuers and other equipment glitches. > > > > Poul-Henning > > > > PS: The thermal mass need not be solid blocks of metal, > > regular ceramic bricks or tiles work fine. > > > > -- > > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > > phk at FreeBSD.ORG | TCP/IP since RFC 956 > > FreeBSD committer | BSD since 4.3-tahoe > > Never attribute to malice what can adequately be explained by > > incompetence. > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. From df6jb at ulrich-bangert.de Thu Jun 11 12:16:05 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 11 Jun 2009 14:16:05 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <20994.1244717410@critter.freebsd.dk> Message-ID: > I'm not talking about crystal ovens, I'm talking about > timekeeping kit in general: how to filter high frequency > temperature fluctuations out, so the PLL does not have to > deal with them. Ok, but in this general case you have to accept the fact, that filtering high temperature fluctuations is only ONE part of the engineering job. The second task (which I tried to point at) is: When you do already have a closed loop temperature regulation system inside what you plan to built around it, then you need to manage the filtering without mal interaction of the local temperature controller with your additional filtering stuff. The art is to make the closed temperature loop inside see only smaller temperature fluctuations but No changes otherwise. If you apply an overall change in temperature insulation to the ambient you will make the work of the inside temperature controller a lot harder because it is not prepared for that. In the aluminium box that i wrote about I have for an experiment replaced the air between the 10811 and the outer box with a material that has a significant lower temperature conductivity than standing air. You can easily watch the temperature controller go crazy with that. For a second experiment I have replaced the air with a material having lots more of thermal conductivity than air and you can watch the temperature controller go crazy with that too. You don't need sophisticated temperature measurement equipment to see the controller go crazy, just watch the frequency of the oscillator. This will tell you all about it. Things are different, if you have an influence on the controller's regulation parameters (which you do not have with a ready bought device). If you do have, then your additional provisions for filtering and insulation can easily be included into the thermal model that the temperature controller has to handle and will lead to different operation parameters of the controller. That will of course work and that is why I compared your suggestions to designing a new oven (for xtal or rubidium or whatever). Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp > Gesendet: Donnerstag, 11. Juni 2009 12:50 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Thunderbolt stability and ambient temperature > > > In message , "Ulrich > Bangert" writes: > >> For PLL steered devices, you want your device enclosed by a > >> thermal mass which is again enclosed by a layer of thermal > >> isolation. The goal is to filter/average all rapid (daily ?) > >> external temperature influences, only letting through such > >> slow variations (seasonal ?) which the PLL can comfortably > cope with. > > > >My impression with this thread is that two sligthly different things > >are being discussed here: > > > >Some posters explain how a crystal oven shall be designed as > >Poul-Henning does with his words above. Absolute correct, no doubt > >about it! > > I'm not talking about crystal ovens, I'm talking about > timekeeping kit in general: how to filter high frequency > temperature fluctuations out, so the PLL does not have to > deal with them. > > The above advice applies to GPSDO's and Rb's and Cs's as well > as TCXOs, OCXOs and voltage references. > > Poul-Henning > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk at FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by > incompetence. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From cfharris at erols.com Thu Jun 11 13:48:20 2009 From: cfharris at erols.com (Chuck Harris) Date: Thu, 11 Jun 2009 09:48:20 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1976.1244706921@critter.freebsd.dk> References: <1976.1244706921@critter.freebsd.dk> Message-ID: <4A310B24.9060504@erols.com> Poul-Henning Kamp wrote: > In message <4A30457E.9060701 at erols.com>, Chuck Harris writes: > >>> And evaporates and leaks. But yes, I've used water for quick jobs. >> I just don't know what to say to that! Even a child can put a >> case of bottled water in a box, and not have it evaporate or leak. >> I would venture that said case of bottled water will still be full >> up when the child graduates from college, and has kids of his own. > > Unless UPS or DHL decides to leave your package stranded on a loading > dock in -20?C for a couple of days. > > In the lab I *might* use water, for shipping I never would. I thought we were talking about stabilizing the temperature environment around frequency/time standards? I recall the discussion talking of big hunks of aluminum, copper, cast-iron engine blocks bought at scrap yards, and other such unshippable things. The nice thing about using water as a thermal ballast is you don't have to ship it specially. It is available everywhere humans go. If you are worried about it freezing, a 50-50 mix with ethylene glycol will protect it from freezing down to -40C, or so, though if we are talking about temperatures like that, it is unlikely that your precision clock is going to work very well down there. -Chuck From jfor at quik.com Thu Jun 11 14:42:06 2009 From: jfor at quik.com (J. Forster) Date: Thu, 11 Jun 2009 07:42:06 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A309CCB.6020009@xtra.co.nz> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <4A309CCB.6020009@xtra.co.nz> Message-ID: <1084.12.6.201.152.1244731326.squirrel@popacctsnew.quik.com> Hey Bruce, Your answers seem somewhat 'mechanical'. Are you a 'bot? Not a joke... REAL question. -John ============== > Rex wrote: >> Hal Murray wrote: >> >>> phk at phk.freebsd.dk said: >>> >>> >>>>> Can I get reflections without some inductance? >>>>> Is there any inductance in a system of alternating >>>>> layers of insulation/storage? >>>>> >>> >>> >>> >>>> I think you are overstretching the badly chosen nomenclatures >>>> parallels to electricity. >>> >>> It was actually a (somewhat?) serious question on several grounds. >>> >>> Can I get reflections from a lumped circuit model of a transmission >>> line made out of just Rs and Cs? If so, I can probably do the same >>> in the thermal world. >>> >>> Can I get reflections in a thermal context? Bruce's URLs say yes, >>> but my math is rusty enough that I can't quickly understand what's >>> going on. >>> >>> If a thermal problem can generate reflections, does that mean it also >>> has something corresponding to inductance? If so, what is it? >>> >>> It's possible that the key idea is time-delay. In the electrical >>> world, a delay is a transmission line which has both C and L. I'm >>> not sure what the one-dimensional equivalent in the thermal world is. >>> >>> What's the speed-of-light equivalent in the thermal world? >>> >>> >>> >>> >>> >> >> Why were you somewhat serious about this? >> >> If you want to extropolate heat into electromagnestic waves, what >> would be the analog of frequency? There are a few parallels in the two >> realms by analogy but that doesn't mean they map in all aspects. >> Sometimes, to help learning ohms law, the analogy of water is used >> with pressure = voltage, flow = current, resistance = narrow pipes. It >> sort of makes the concepts easier to grasp, but when you get to AC and >> wave reflections I think one has to struggle to make the water analogy >> useful. For heat, I think the water analog might be more useful than >> trying to map the EM waves to heat. >> >> The reflection idea did remind me of something that occurred to me, a >> gallows-humor joke from years back. I'm sure most of you remember >> hearing about the 1989 San Francisco earthquake. The earthquake >> epicenter was between Santa Cruz and San Jose, about 40 miles south of >> San Francisco, but a lot of the serious damage and fires occurred in >> San Francisco near the tip of the penninsula at the bay shore. There >> was a lot of discussion about this localized damage so far away, and >> how that could happen. San Francisco is at the tip of a peninsula that >> forms the Bay. I immediately thought that the problem was obvious. The >> penninsula was excited at its bottom end and was left improperly >> terminated at San Francisco. I couldn't tell this joke for two >> reasons, one: it was in bad taste, but two: I only knew a few people >> who would get it -- the mismatch/termination joke. >> >> Now, back to the subject of heat, I have a strange observation that I >> posted on the web a few years ago. A few people thought they had seen >> the same thing, but most thought what I noticed was not real. I posted >> because, if it was true, it seemed unexpected and I had never heard >> anything that could explain it. >> >> I was welding or heat treating steel. Imagine a steel bar about 1 inch >> (2.54 cm) in diameter and a foot to 18 " (30-40 cm) long. The bar is >> clamped in a vise and with a torch one end is quickly brought up to >> red heat. The other end is still cool enough that with my bare hand I >> can hold the bar by the cool end and carry it into the next room. I >> carry it there to cool it in the sink. A stream of cold water turned >> on, I quickly cool the hot end in the water. My observation, from >> doing this several times, is that the cold water quickly absorbes heat >> from the red end, but also seems to chase a lot of the heat quickly up >> toward the cold end, making the bar rapidly uncomfortable to hold. So >> that's my observation. I think the sudden cooling of the very hot end >> has somehow chased a glob of heat toward the cool end. If true, I have >> no explanation. I don't think it is related to steam; it seems to me >> to be something happening inside the bar. >> >> Most people thought it was coincidence of heat propagating up the bar >> just at that time, or steam. Could be, but I still think it is real. >> The cold end of the bar was slowly getting warmer as I carried it, but >> after the sudden cooling of the hot end, the cold end seemed to get >> hot fast. >> >> I meant to try an experiment with two bars and dual thermocouples, but >> I never got around to it. The main problem is getting things close >> enough to compare without questioning the heated states. My plan would >> have been: attach two themocouples to the cold end of two identical >> bars. Heat the two other ends rapidly to red heat (that is the very >> hard part to get right and balanced) and then just cool one bar >> rapidly while recording both temp profiles of the cold ends. If I >> figure out how to do the heating quick and balanced, I may still try >> the experiment. >> >> So I started with a bit of complaining about the rambling of the >> thread, and now I've rambled it in a whole nother direction. Sorry, I >> guess. >> >> >> >> >> >> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > Rex > > your experience with the hot bar is quite common. > > Bruce > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From jfor at quik.com Thu Jun 11 14:51:01 2009 From: jfor at quik.com (J. Forster) Date: Thu, 11 Jun 2009 07:51:01 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A30B254.3070408@rubidium.dyndns.org> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <4A30B254.3070408@rubidium.dyndns.org> Message-ID: <1093.12.6.201.152.1244731861.squirrel@popacctsnew.quik.com> This is an absolutely standard problem in an undergraduate Heat Transfer course. Look for heating or cooling a block of material and thermal diffusivity. Take a look at most any decent text (Rosenow(?) & Choi, 'Heat, Mass, & Momentom Transfer') for example) That said, the geometry of a ham makes a closed form solution more difficult, requiring numerical methods. -John ============ > As we are fairly off track here, let me relay a similar story. My mother > has been working with food all her professional life. A christmas > tradition here in Sweden is to have big lumps of ham from which you > carve slices. However, the damn thing needs to be cooked. If you do it > in the oven it dries out, if you only boil it you do not get that crisp > surface people want. You can do a bit of both. However, one year she > thought about cooking it in the microwave oven. She has no formal > training in thermodynamics and didn't really involve me in the thought > process, but she figured that if she ran the microwave for half an hour, > after wrapping the ham in microwave-grade plastic, just to avoid it to > dry out, and then just let it sit on the bench, then it would hit those > 70 degrees in the core after a while anyway. Sure thing, it did. Worked > like a charm. Perfectly cooked, juicy. What happends is that it takes > time for the heat-wave to reach the core, so even if she stopped > providing more heat the heat-wave was still in progress and just could > not be stopped. From jfor at quik.com Thu Jun 11 15:00:53 2009 From: jfor at quik.com (J. Forster) Date: Thu, 11 Jun 2009 08:00:53 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <2007.1244707410@critter.freebsd.dk> References: <2007.1244707410@critter.freebsd.dk> Message-ID: <1099.12.6.201.152.1244732453.squirrel@popacctsnew.quik.com> It has nothing to do with this. A long (length >> width) bar can simply be modeled as a long ladder of series resistors's and capacitors to ground: ---zzz---zzz---zzz---- ... ---zzz--- _|_ _|_ _|_ _|_ ___ ___ ___ ___ ----| ----|-----|----- ... ----|----- If you put a rectangular pulse in the left end, it will emerge later and very much rounded at the right end. Either do the math or simulate it in Spice or with a handful of R's and C's and a pulse generator and scope. No inductors needed. PERIOD. That model fully accounts for your observations with the bar heated at one end. -John ================= > In message <4A309B30.7000400 at sonic.net>, Rex writes: > >>My observation, from doing this >>several times, is that the cold water quickly absorbes heat from the red >>end, but also seems to chase a lot of the heat quickly up toward the >>cold end, making the bar rapidly uncomfortable to hold. > > I've seen the effect you describe explained in an article somewhere, > very likely New Scientist or SciAm about five years ago. > > When you rapidly heat or cool metals, very often changes in crystal > lattice structure is involved some of them resulting in quite drastic > changes to volume. > > Heat is essentially atoms wiggling about, and when you change the > modes of freedom for the atoms, they may have to wiggle harder. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk at FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by > incompetence. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From ed_palmer at sasktel.net Thu Jun 11 15:22:00 2009 From: ed_palmer at sasktel.net (Ed Palmer) Date: Thu, 11 Jun 2009 09:22:00 -0600 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A312118.5010804@sasktel.net> Ulrich, when you changed the thermal characteristics around your 10811, how 'crazy' did it become? According to your theory, there should be differences in the schematics of the oven controllers between the single and double oven variants of the 10811. Last year I picked up a couple of those double oven 10811s from China that had the outer insulation removed. I wonder if I could see any anomalies in its operation with no outer insulation and only the inner oven operating. Ed Ulrich Bangert wrote: >> I'm not talking about crystal ovens, I'm talking about >> timekeeping kit in general: how to filter high frequency >> temperature fluctuations out, so the PLL does not have to >> deal with them. >> > > Ok, but in this general case you have to accept the fact, that filtering > high temperature fluctuations is only ONE part of the engineering job. The > second task (which I tried to point at) is: When you do already have a > closed loop temperature regulation system inside what you plan to built > around it, then you need to manage the filtering without mal interaction of > the local temperature controller with your additional filtering stuff. The > art is to make the closed temperature loop inside see only smaller > temperature fluctuations but No changes otherwise. > > If you apply an overall change in temperature insulation to the ambient you > will make the work of the inside temperature controller a lot harder because > it is not prepared for that. In the aluminium box that i wrote about I have > for an experiment replaced the air between the 10811 and the outer box with > a material that has a significant lower temperature conductivity than > standing air. You can easily watch the temperature controller go crazy with > that. For a second experiment I have replaced the air with a material having > lots more of thermal conductivity than air and you can watch the temperature > controller go crazy with that too. You don't need sophisticated temperature > measurement equipment to see the controller go crazy, just watch the > frequency of the oscillator. This will tell you all about it. > > Things are different, if you have an influence on the controller's > regulation parameters (which you do not have with a ready bought device). If > you do have, then your additional provisions for filtering and insulation > can easily be included into the thermal model that the temperature > controller has to handle and will lead to different operation parameters of > the controller. That will of course work and that is why I compared your > suggestions to designing a new oven (for xtal or rubidium or whatever). > > Best regards > Ulrich Bangert > > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp >> Gesendet: Donnerstag, 11. Juni 2009 12:50 >> An: Discussion of precise time and frequency measurement >> Betreff: Re: [time-nuts] Thunderbolt stability and ambient temperature >> >> >> In message , "Ulrich >> Bangert" writes: >> >>>> For PLL steered devices, you want your device enclosed by a >>>> thermal mass which is again enclosed by a layer of thermal >>>> isolation. The goal is to filter/average all rapid (daily ?) >>>> external temperature influences, only letting through such >>>> slow variations (seasonal ?) which the PLL can comfortably >>>> >> cope with. >> >>> My impression with this thread is that two sligthly different things >>> are being discussed here: >>> >>> Some posters explain how a crystal oven shall be designed as >>> Poul-Henning does with his words above. Absolute correct, no doubt >>> about it! >>> >> I'm not talking about crystal ovens, I'm talking about >> timekeeping kit in general: how to filter high frequency >> temperature fluctuations out, so the PLL does not have to >> deal with them. >> >> The above advice applies to GPSDO's and Rb's and Cs's as well >> as TCXOs, OCXOs and voltage references. >> >> Poul-Henning >> >> -- >> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >> phk at FreeBSD.ORG | TCP/IP since RFC 956 >> FreeBSD committer | BSD since 4.3-tahoe >> Never attribute to malice what can adequately be explained by >> incompetence. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From Arnold.Tibus at gmx.de Thu Jun 11 16:42:57 2009 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Thu, 11 Jun 2009 18:42:57 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A312118.5010804@sasktel.net> Message-ID: Ed, and the big group I did run such a 10811 without the outer heater connected and without any insulation around as replacement for the original insulation and box but I did not see any fluctuations beside the normal behaviour of a 10811. (I have to admit that I did not yet run precision records, neither for the heater current nor for the frequency output. I see what I have to do soon!) This model is obviously adjusted inside to work best in an encreased environment of around 40 to 45 deg. C . I think as Ulrich does explain, blocking the heat flow significantly must deteriorate the regulating loop parameters. The life time of the oscillator electronics outside the stabilized crystal element will as well decrease... A good idea in fact to put the standard in a stable area and very slow varying temp range of around 15 deg. C underneath the house fundaments...I will think about! Did anybody ever think to apply wood as stabilizing element around an oscillator? Wood behaves a bit strange, it is on one side a not bad insulator and it does have as well a quite high heat storage capacity! (Oak with around 2.4 J/g, K., Lambda 0.17 W/m.K,, Pine around 2.7 J/g.K., Lambda 0.14 W/m.K. Water around 4.18 J/g.K., Lambda 0,604 W/m.K. Copper has 0.385 2.4 J/g, K., Lambda 401 W/m.K. at 25 deg. C. ) I consider wood a very intersting material, cheap and easy to work... Arnold On Thu, 11 Jun 2009 09:22:00 -0600, Ed Palmer wrote: >Ulrich, when you changed the thermal characteristics around your 10811, >how 'crazy' did it become? >According to your theory, there should be differences in the schematics >of the oven controllers between the single and double oven variants of >the 10811. Last year I picked up a couple of those double oven 10811s >from China that had the outer insulation removed. I wonder if I could >see any anomalies in its operation with no outer insulation and only the >inner oven operating. >Ed >Ulrich Bangert wrote: >>> I'm not talking about crystal ovens, I'm talking about >>> timekeeping kit in general: how to filter high frequency >>> temperature fluctuations out, so the PLL does not have to >>> deal with them. >>> >> >> Ok, but in this general case you have to accept the fact, that filtering >> high temperature fluctuations is only ONE part of the engineering job. The >> second task (which I tried to point at) is: When you do already have a >> closed loop temperature regulation system inside what you plan to built >> around it, then you need to manage the filtering without mal interaction of >> the local temperature controller with your additional filtering stuff. The >> art is to make the closed temperature loop inside see only smaller >> temperature fluctuations but No changes otherwise. >> >> If you apply an overall change in temperature insulation to the ambient you >> will make the work of the inside temperature controller a lot harder because >> it is not prepared for that. In the aluminium box that i wrote about I have >> for an experiment replaced the air between the 10811 and the outer box with >> a material that has a significant lower temperature conductivity than >> standing air. You can easily watch the temperature controller go crazy with >> that. For a second experiment I have replaced the air with a material having >> lots more of thermal conductivity than air and you can watch the temperature >> controller go crazy with that too. You don't need sophisticated temperature >> measurement equipment to see the controller go crazy, just watch the >> frequency of the oscillator. This will tell you all about it. >> >> Things are different, if you have an influence on the controller's >> regulation parameters (which you do not have with a ready bought device). If >> you do have, then your additional provisions for filtering and insulation >> can easily be included into the thermal model that the temperature >> controller has to handle and will lead to different operation parameters of >> the controller. That will of course work and that is why I compared your >> suggestions to designing a new oven (for xtal or rubidium or whatever). >> >> Best regards >> Ulrich Bangert >> >> >>> -----Ursprungliche Nachricht----- >>> Von: time-nuts-bounces at febo.com >>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp >>> Gesendet: Donnerstag, 11. Juni 2009 12:50 >>> An: Discussion of precise time and frequency measurement >>> Betreff: Re: [time-nuts] Thunderbolt stability and ambient temperature >>> >>> >>> In message , "Ulrich >>> Bangert" writes: >>> >>>>> For PLL steered devices, you want your device enclosed by a >>>>> thermal mass which is again enclosed by a layer of thermal >>>>> isolation. The goal is to filter/average all rapid (daily ?) >>>>> external temperature influences, only letting through such >>>>> slow variations (seasonal ?) which the PLL can comfortably >>>>> >>> cope with. >>> >>>> My impression with this thread is that two sligthly different things >>>> are being discussed here: >>>> >>>> Some posters explain how a crystal oven shall be designed as >>>> Poul-Henning does with his words above. Absolute correct, no doubt >>>> about it! >>>> >>> I'm not talking about crystal ovens, I'm talking about >>> timekeeping kit in general: how to filter high frequency >>> temperature fluctuations out, so the PLL does not have to >>> deal with them. >>> >>> The above advice applies to GPSDO's and Rb's and Cs's as well >>> as TCXOs, OCXOs and voltage references. >>> >>> Poul-Henning >>> >>> -- >>> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >>> phk at FreeBSD.ORG | TCP/IP since RFC 956 >>> FreeBSD committer | BSD since 4.3-tahoe >>> Never attribute to malice what can adequately be explained by >>> incompetence. >>> From djl at montana.com Thu Jun 11 18:00:37 2009 From: djl at montana.com (Don Latham) Date: Thu, 11 Jun 2009 12:00:37 -0600 (MDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: I have a General Radio 100KHz crystal oven that is inside a crafted wood box. The oven uses a mercury thermometer with a pair of wires sealed in the side to implement a bang-bang servo. The wood box will thus smooth out the square wave heat pulse. I think it came from something like an LR-1 Navy signal generator as a calibration standard. I need to put an oscillator circuit on it in order to characterize its behavior. It's on the FIFO to-do stack... Don Arnold Tibus > Ed, > and the big group > > I did run such a 10811 without the outer heater connected and without > any insulation around as replacement for the original insulation and box > but I did not see any fluctuations beside the normal behaviour of a 10811. > > (I have to admit that I did not yet run precision records, neither for the > heater current nor for the frequency output. I see what I have to do > soon!) > > This model is obviously adjusted inside to work best in an encreased > environment of around 40 to 45 deg. C . > > I think as Ulrich does explain, blocking the heat flow significantly must > deteriorate the regulating loop parameters. The life time of the > oscillator > electronics outside the stabilized crystal element will as well > decrease... > > A good idea in fact to put the standard in a stable area and very slow > varying temp range of around 15 deg. C underneath the house > fundaments...I will think about! > > Did anybody ever think to apply wood as stabilizing element around an > oscillator? Wood behaves a bit strange, it is on one side a not bad > insulator and it does have as well a quite high heat storage capacity! > > (Oak with around 2.4 J/g, K., Lambda 0.17 W/m.K,, > Pine around 2.7 J/g.K., Lambda 0.14 W/m.K. > Water around 4.18 J/g.K., Lambda 0,604 W/m.K. > Copper has 0.385 2.4 J/g, K., Lambda 401 W/m.K. at 25 deg. C. ) > I consider wood a very intersting material, cheap and easy to work... > > Arnold > > > > On Thu, 11 Jun 2009 09:22:00 -0600, Ed Palmer wrote: > >>Ulrich, when you changed the thermal characteristics around your 10811, >>how 'crazy' did it become? > >>According to your theory, there should be differences in the schematics >>of the oven controllers between the single and double oven variants of >>the 10811. Last year I picked up a couple of those double oven 10811s >>from China that had the outer insulation removed. I wonder if I could >>see any anomalies in its operation with no outer insulation and only the >>inner oven operating. > >>Ed > >>Ulrich Bangert wrote: >>>> I'm not talking about crystal ovens, I'm talking about >>>> timekeeping kit in general: how to filter high frequency >>>> temperature fluctuations out, so the PLL does not have to >>>> deal with them. >>>> >>> >>> Ok, but in this general case you have to accept the fact, that >>> filtering >>> high temperature fluctuations is only ONE part of the engineering job. >>> The >>> second task (which I tried to point at) is: When you do already have a >>> closed loop temperature regulation system inside what you plan to built >>> around it, then you need to manage the filtering without mal >>> interaction of >>> the local temperature controller with your additional filtering stuff. >>> The >>> art is to make the closed temperature loop inside see only smaller >>> temperature fluctuations but No changes otherwise. >>> >>> If you apply an overall change in temperature insulation to the ambient >>> you >>> will make the work of the inside temperature controller a lot harder >>> because >>> it is not prepared for that. In the aluminium box that i wrote about I >>> have >>> for an experiment replaced the air between the 10811 and the outer box >>> with >>> a material that has a significant lower temperature conductivity than >>> standing air. You can easily watch the temperature controller go crazy >>> with >>> that. For a second experiment I have replaced the air with a material >>> having >>> lots more of thermal conductivity than air and you can watch the >>> temperature >>> controller go crazy with that too. You don't need sophisticated >>> temperature >>> measurement equipment to see the controller go crazy, just watch the >>> frequency of the oscillator. This will tell you all about it. >>> >>> Things are different, if you have an influence on the controller's >>> regulation parameters (which you do not have with a ready bought >>> device). If >>> you do have, then your additional provisions for filtering and >>> insulation >>> can easily be included into the thermal model that the temperature >>> controller has to handle and will lead to different operation >>> parameters of >>> the controller. That will of course work and that is why I compared >>> your >>> suggestions to designing a new oven (for xtal or rubidium or whatever). >>> >>> Best regards >>> Ulrich Bangert >>> >>> >>>> -----Ursprungliche Nachricht----- >>>> Von: time-nuts-bounces at febo.com >>>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp >>>> Gesendet: Donnerstag, 11. Juni 2009 12:50 >>>> An: Discussion of precise time and frequency measurement >>>> Betreff: Re: [time-nuts] Thunderbolt stability and ambient temperature >>>> >>>> >>>> In message , "Ulrich >>>> Bangert" writes: >>>> >>>>>> For PLL steered devices, you want your device enclosed by a >>>>>> thermal mass which is again enclosed by a layer of thermal >>>>>> isolation. The goal is to filter/average all rapid (daily ?) >>>>>> external temperature influences, only letting through such >>>>>> slow variations (seasonal ?) which the PLL can comfortably >>>>>> >>>> cope with. >>>> >>>>> My impression with this thread is that two sligthly different things >>>>> are being discussed here: >>>>> >>>>> Some posters explain how a crystal oven shall be designed as >>>>> Poul-Henning does with his words above. Absolute correct, no doubt >>>>> about it! >>>>> >>>> I'm not talking about crystal ovens, I'm talking about >>>> timekeeping kit in general: how to filter high frequency >>>> temperature fluctuations out, so the PLL does not have to >>>> deal with them. >>>> >>>> The above advice applies to GPSDO's and Rb's and Cs's as well >>>> as TCXOs, OCXOs and voltage references. >>>> >>>> Poul-Henning >>>> >>>> -- >>>> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >>>> phk at FreeBSD.ORG | TCP/IP since RFC 956 >>>> FreeBSD committer | BSD since 4.3-tahoe >>>> Never attribute to malice what can adequately be explained by >>>> incompetence. >>>> > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com From danrae at verizon.net Thu Jun 11 17:26:44 2009 From: danrae at verizon.net (Dan Rae) Date: Thu, 11 Jun 2009 10:26:44 -0700 Subject: [time-nuts] E1938 question Message-ID: <4A313E54.5020109@verizon.net> I have one of the "Chinese" E1938 modules I bought about a month ago. I just tried it out on the bench, and have not had much luck with it. The 5 Volt supply never goes above 50 mA or so, none of the heaters seem to be powered looking at the "hockey puck" D-sub connector pins. The four leds up by the PIC (?) seem to flash once on switch on and then pulse about once a second. The other led which seems to be on the 5 V supply is on. It does oscillate, but very low since it never warms up. Is there any point in my trying to go any further with this? It seems pretty dead to me, the PIC maybe? :^( Nice museum piece perhaps, but a bit expensive for only that... Dan ac6ao From tvb at LeapSecond.com Thu Jun 11 18:11:38 2009 From: tvb at LeapSecond.com (Tom Van Baak) Date: Thu, 11 Jun 2009 11:11:38 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature References: <4A312118.5010804@sasktel.net> Message-ID: <1E7D846F9D87455D8DC97FCEC59C775B@pc52> > According to your theory, there should be differences in the schematics > of the oven controllers between the single and double oven variants of > the 10811. Last year I picked up a couple of those double oven 10811s > from China that had the outer insulation removed. I wonder if I could > see any anomalies in its operation with no outer insulation and only the > inner oven operating. My understanding is that the unique "double" oven 10811 found in the Z3801A is not there for improved temperature stability, but simply so that this first-generation GPSDO can power up within spec in ultra cold (like minus 40) telecom environments. No other hp/Agilent instrument uses an external outer oven around the 10811 as far as I know. Does anyone on the list have access to a low temperature test chamber? It would be interesting to see how slowly a 10544 or 10811 warms up from that cold environment as compared to a more modern and compact E1938 or MTI or TBolt-style OCXO. /tvb From pete at petelancashire.com Thu Jun 11 18:19:27 2009 From: pete at petelancashire.com (Pete Lancashire) Date: Thu, 11 Jun 2009 11:19:27 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <3158946b124f180fa783892091b96588.squirrel@petelancashire.com> I use to have a similar on from GR but was lost in a fire. It had a large GR metal name plate on one side. I sanded and varnished the box and had it on display for quite a long time. GR was great at stretching the mechanical limits of material to get electrical specs. -pete > I have a General Radio 100KHz crystal oven that is inside a crafted wood > box. The oven uses a mercury thermometer with a pair of wires sealed in > the side to implement a bang-bang servo. The wood box will thus smooth out > the square wave heat pulse. I think it came from something like an LR-1 > Navy signal generator as a calibration standard. I need to put an > oscillator circuit on it in order to characterize its behavior. It's on > the FIFO to-do stack... > Don > > Arnold Tibus >> Ed, >> and the big group >> >> I did run such a 10811 without the outer heater connected and without >> any insulation around as replacement for the original insulation and box >> but I did not see any fluctuations beside the normal behaviour of a >> 10811. >> >> (I have to admit that I did not yet run precision records, neither for >> the >> heater current nor for the frequency output. I see what I have to do >> soon!) >> >> This model is obviously adjusted inside to work best in an encreased >> environment of around 40 to 45 deg. C . >> >> I think as Ulrich does explain, blocking the heat flow significantly >> must >> deteriorate the regulating loop parameters. The life time of the >> oscillator >> electronics outside the stabilized crystal element will as well >> decrease... >> >> A good idea in fact to put the standard in a stable area and very slow >> varying temp range of around 15 deg. C underneath the house >> fundaments...I will think about! >> >> Did anybody ever think to apply wood as stabilizing element around an >> oscillator? Wood behaves a bit strange, it is on one side a not bad >> insulator and it does have as well a quite high heat storage capacity! >> >> (Oak with around 2.4 J/g, K., Lambda 0.17 W/m.K,, >> Pine around 2.7 J/g.K., Lambda 0.14 W/m.K. >> Water around 4.18 J/g.K., Lambda 0,604 W/m.K. >> Copper has 0.385 2.4 J/g, K., Lambda 401 W/m.K. at 25 deg. C. ) >> I consider wood a very intersting material, cheap and easy to work... >> >> Arnold >> >> >> >> On Thu, 11 Jun 2009 09:22:00 -0600, Ed Palmer wrote: >> >>>Ulrich, when you changed the thermal characteristics around your 10811, >>>how 'crazy' did it become? >> >>>According to your theory, there should be differences in the schematics >>>of the oven controllers between the single and double oven variants of >>>the 10811. Last year I picked up a couple of those double oven 10811s >>>from China that had the outer insulation removed. I wonder if I could >>>see any anomalies in its operation with no outer insulation and only the >>>inner oven operating. >> >>>Ed >> >>>Ulrich Bangert wrote: >>>>> I'm not talking about crystal ovens, I'm talking about >>>>> timekeeping kit in general: how to filter high frequency >>>>> temperature fluctuations out, so the PLL does not have to >>>>> deal with them. >>>>> >>>> >>>> Ok, but in this general case you have to accept the fact, that >>>> filtering >>>> high temperature fluctuations is only ONE part of the engineering job. >>>> The >>>> second task (which I tried to point at) is: When you do already have a >>>> closed loop temperature regulation system inside what you plan to >>>> built >>>> around it, then you need to manage the filtering without mal >>>> interaction of >>>> the local temperature controller with your additional filtering stuff. >>>> The >>>> art is to make the closed temperature loop inside see only smaller >>>> temperature fluctuations but No changes otherwise. >>>> >>>> If you apply an overall change in temperature insulation to the >>>> ambient >>>> you >>>> will make the work of the inside temperature controller a lot harder >>>> because >>>> it is not prepared for that. In the aluminium box that i wrote about I >>>> have >>>> for an experiment replaced the air between the 10811 and the outer box >>>> with >>>> a material that has a significant lower temperature conductivity than >>>> standing air. You can easily watch the temperature controller go crazy >>>> with >>>> that. For a second experiment I have replaced the air with a material >>>> having >>>> lots more of thermal conductivity than air and you can watch the >>>> temperature >>>> controller go crazy with that too. You don't need sophisticated >>>> temperature >>>> measurement equipment to see the controller go crazy, just watch the >>>> frequency of the oscillator. This will tell you all about it. >>>> >>>> Things are different, if you have an influence on the controller's >>>> regulation parameters (which you do not have with a ready bought >>>> device). If >>>> you do have, then your additional provisions for filtering and >>>> insulation >>>> can easily be included into the thermal model that the temperature >>>> controller has to handle and will lead to different operation >>>> parameters of >>>> the controller. That will of course work and that is why I compared >>>> your >>>> suggestions to designing a new oven (for xtal or rubidium or >>>> whatever). >>>> >>>> Best regards >>>> Ulrich Bangert >>>> >>>> >>>>> -----Ursprungliche Nachricht----- >>>>> Von: time-nuts-bounces at febo.com >>>>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Poul-Henning Kamp >>>>> Gesendet: Donnerstag, 11. Juni 2009 12:50 >>>>> An: Discussion of precise time and frequency measurement >>>>> Betreff: Re: [time-nuts] Thunderbolt stability and ambient >>>>> temperature >>>>> >>>>> >>>>> In message , "Ulrich >>>>> Bangert" writes: >>>>> >>>>>>> For PLL steered devices, you want your device enclosed by a >>>>>>> thermal mass which is again enclosed by a layer of thermal >>>>>>> isolation. The goal is to filter/average all rapid (daily ?) >>>>>>> external temperature influences, only letting through such >>>>>>> slow variations (seasonal ?) which the PLL can comfortably >>>>>>> >>>>> cope with. >>>>> >>>>>> My impression with this thread is that two sligthly different things >>>>>> are being discussed here: >>>>>> >>>>>> Some posters explain how a crystal oven shall be designed as >>>>>> Poul-Henning does with his words above. Absolute correct, no doubt >>>>>> about it! >>>>>> >>>>> I'm not talking about crystal ovens, I'm talking about >>>>> timekeeping kit in general: how to filter high frequency >>>>> temperature fluctuations out, so the PLL does not have to >>>>> deal with them. >>>>> >>>>> The above advice applies to GPSDO's and Rb's and Cs's as well >>>>> as TCXOs, OCXOs and voltage references. >>>>> >>>>> Poul-Henning >>>>> >>>>> -- >>>>> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >>>>> phk at FreeBSD.ORG | TCP/IP since RFC 956 >>>>> FreeBSD committer | BSD since 4.3-tahoe >>>>> Never attribute to malice what can adequately be explained by >>>>> incompetence. >>>>> >> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > -- > Dr. Don Latham AJ7LL > Six Mile Systems LLP > 17850 Six Mile Road > POB 134 > Huson, MT, 59846 > VOX 406-626-4304 > www.lightningforensics.com > www.sixmilesystems.com > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From pete at petelancashire.com Thu Jun 11 18:42:33 2009 From: pete at petelancashire.com (Pete Lancashire) Date: Thu, 11 Jun 2009 11:42:33 -0700 Subject: [time-nuts] IEEE - Fifty Years of Progress in Quartz Crystal Frequency Standards In-Reply-To: <3158946b124f180fa783892091b96588.squirrel@petelancashire.com> References: <3158946b124f180fa783892091b96588.squirrel@petelancashire.com> Message-ID: maybe of interest IEEE Ultrasonics, Ferroelectrics, and Frequency Control Society "Fifty Years of Progress in Quartz Crystal Frequency Standards" http://www.ieee-uffc.org/main/history.asp?file=frerking and some other historical pubs http://www.ieee-uffc.org/main/history.asp -pete From phk at phk.freebsd.dk Thu Jun 11 21:59:37 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Thu, 11 Jun 2009 21:59:37 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Your message of "Thu, 11 Jun 2009 14:16:05 +0200." Message-ID: <23086.1244757577@critter.freebsd.dk> In message , "Ulrich Bangert" writes: >> I'm not talking about crystal ovens, I'm talking about >> timekeeping kit in general: how to filter high frequency >> temperature fluctuations out, so the PLL does not have to >> deal with them. > >If you apply an overall change in temperature insulation to the ambient [...] Which is why I suggested using an old, unplugged fridge. Your typical time-nuts kit will not have a heatflow that can warm the interior of a fridge signifiantly, but the thermal inertia of the fridge is perfect for reducing temperature fluctuations. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From cfharris at erols.com Thu Jun 11 22:11:06 2009 From: cfharris at erols.com (Chuck Harris) Date: Thu, 11 Jun 2009 18:11:06 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <23086.1244757577@critter.freebsd.dk> References: <23086.1244757577@critter.freebsd.dk> Message-ID: <4A3180FA.9040808@erols.com> Poul-Henning Kamp wrote: > In message , "Ulrich Bangert" writes: >>> I'm not talking about crystal ovens, I'm talking about >>> timekeeping kit in general: how to filter high frequency >>> temperature fluctuations out, so the PLL does not have to >>> deal with them. > >> If you apply an overall change in temperature insulation to the ambient [...] > > Which is why I suggested using an old, unplugged fridge. > > Your typical time-nuts kit will not have a heatflow that can warm the > interior of a fridge signifiantly, but the thermal inertia of the fridge > is perfect for reducing temperature fluctuations. I really hate the idea of using an old fridge. After any amount of use, they have enough spilled food and drink in the cracks and crevices to smell really funky if you let them warm up with the door closed. I would much rather bang together a small closet out of 2x4's and insulate it with fiber glass than use a fridge. That said, the welding shops often use an old fridge for storage of welding rods. They rewire the door switch so that the light stays on all the time, and replace the bulb with a 100W bulb. The fridge will heat up to near the boiling point of water from just the heat of the light bulb. My environmental chamber will heat up to 70C from just the heat of the 60W bulb in the chamber. -Chuck Harris From bruce.griffiths at xtra.co.nz Thu Jun 11 23:03:46 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 11:03:46 +1200 Subject: [time-nuts] E1938 question In-Reply-To: <4A313E54.5020109@verizon.net> References: <4A313E54.5020109@verizon.net> Message-ID: <4A318D52.9070806@xtra.co.nz> Dan Rae wrote: > I have one of the "Chinese" E1938 modules I bought about a month ago. > I just tried it out on the bench, and have not had much luck with it. > The 5 Volt supply never goes above 50 mA or so, none of the heaters > seem to be powered looking at the "hockey puck" D-sub connector pins. > The four leds up by the PIC (?) seem to flash once on switch on and > then pulse about once a second. The other led which seems to be on > the 5 V supply is on. It does oscillate, but very low since it never > warms up. > > Is there any point in my trying to go any further with this? It seems > pretty dead to me, the PIC maybe? :^( > > Nice museum piece perhaps, but a bit expensive for only that... > > Dan > > ac6ao > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > You did connect the 12V supply as well? The output signal level is only about +4dBm. Bruce From bruce.griffiths at xtra.co.nz Thu Jun 11 23:24:21 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 11:24:21 +1200 Subject: [time-nuts] E1938 question In-Reply-To: <4A313E54.5020109@verizon.net> References: <4A313E54.5020109@verizon.net> Message-ID: <4A319225.2050507@xtra.co.nz> Dan Rae wrote: > I have one of the "Chinese" E1938 modules I bought about a month ago. > I just tried it out on the bench, and have not had much luck with it. > The 5 Volt supply never goes above 50 mA or so, none of the heaters > seem to be powered looking at the "hockey puck" D-sub connector pins. > The four leds up by the PIC (?) seem to flash once on switch on and > then pulse about once a second. The other led which seems to be on > the 5 V supply is on. It does oscillate, but very low since it never > warms up. > > Is there any point in my trying to go any further with this? It seems > pretty dead to me, the PIC maybe? :^( > > Nice museum piece perhaps, but a bit expensive for only that... > > Dan > > ac6ao > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > When operating correctly: 1) The green power led near the heater PMOSFETS should be on continuously 2) The green led at the other end of the board should flash at 1Hz. 3) The oven takes several minutes to warm up and the outer oven shell should be noticeably warm. If other LEDs are flashing the PIC may be locked in the wrong mode. This state can sometimes be cleared by resetting the PIC by powering it down and restarting. Bruce From bruce.griffiths at xtra.co.nz Thu Jun 11 23:36:12 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 11:36:12 +1200 Subject: [time-nuts] E1938 question In-Reply-To: <4A313E54.5020109@verizon.net> References: <4A313E54.5020109@verizon.net> Message-ID: <4A3194EC.6070401@xtra.co.nz> Dan Rae wrote: > I have one of the "Chinese" E1938 modules I bought about a month ago. > I just tried it out on the bench, and have not had much luck with it. > The 5 Volt supply never goes above 50 mA or so, none of the heaters > seem to be powered looking at the "hockey puck" D-sub connector pins. > The four leds up by the PIC (?) seem to flash once on switch on and > then pulse about once a second. The other led which seems to be on > the 5 V supply is on. It does oscillate, but very low since it never > warms up. > > Is there any point in my trying to go any further with this? It seems > pretty dead to me, the PIC maybe? :^( > > Nice museum piece perhaps, but a bit expensive for only that... > > Dan > > ac6ao > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Have you checked that the outputs of all the regulators on the board are OK. In particular the -5V rail used by the heater PMOSFET driver opamps? Bruce From bruce.griffiths at xtra.co.nz Thu Jun 11 23:56:07 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 11:56:07 +1200 Subject: [time-nuts] E1938 question In-Reply-To: <4A313E54.5020109@verizon.net> References: <4A313E54.5020109@verizon.net> Message-ID: <4A319997.8020800@xtra.co.nz> Dan Rae wrote: > I have one of the "Chinese" E1938 modules I bought about a month ago. > I just tried it out on the bench, and have not had much luck with it. > The 5 Volt supply never goes above 50 mA or so, none of the heaters > seem to be powered looking at the "hockey puck" D-sub connector pins. > The four leds up by the PIC (?) seem to flash once on switch on and > then pulse about once a second. The other led which seems to be on > the 5 V supply is on. It does oscillate, but very low since it never > warms up. > > Is there any point in my trying to go any further with this? It seems > pretty dead to me, the PIC maybe? :^( > > Nice museum piece perhaps, but a bit expensive for only that... > > Dan > > ac6ao > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > You can also try pushing the PIC reset button near the front of the board. Bruce From tvb at LeapSecond.com Fri Jun 12 00:02:02 2009 From: tvb at LeapSecond.com (Tom Van Baak) Date: Thu, 11 Jun 2009 17:02:02 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> Message-ID: <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> > Most people thought it was coincidence of heat propagating up the bar > just at that time, or steam. Could be, but I still think it is real. The > cold end of the bar was slowly getting warmer as I carried it, but after > the sudden cooling of the hot end, the cold end seemed to get hot fast. Rex, We know each material has it's own thermal conductivity. Copper is 401 W/m-K and steel only about 1/10th that, etc. It would appear from conductivity tables in books that these are fixed constants. But I wonder if near-liquid (red hot) steel has a different (e.g., even lower) value than warm or cold steel? Is metal thermal conductivity actually a fixed constant or is it a function of temperature over a wide range of temperature? If so, not only is the temperature changing when you drop the steel in water, but also the thermal conductivity of the steel. Thus, depending on how fast or slowly you cool it vs. how non-linear the conductivity is as a function of temperature, I imagine you could observe the very effect you describe. /tvb From bruce.griffiths at xtra.co.nz Fri Jun 12 00:11:25 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 12:11:25 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> Message-ID: <4A319D2D.1000903@xtra.co.nz> Tom Van Baak wrote: >> Most people thought it was coincidence of heat propagating up the bar >> just at that time, or steam. Could be, but I still think it is real. >> The cold end of the bar was slowly getting warmer as I carried it, >> but after the sudden cooling of the hot end, the cold end seemed to >> get hot fast. > > Rex, > > We know each material has it's own thermal conductivity. Copper > is 401 W/m-K and steel only about 1/10th that, etc. It would appear > from conductivity tables in books that these are fixed constants. > > But I wonder if near-liquid (red hot) steel has a different (e.g., even > lower) value than warm or cold steel? Is metal thermal conductivity > actually a fixed constant or is it a function of temperature over a > wide range of temperature? > > If so, not only is the temperature changing when you drop the > steel in water, but also the thermal conductivity of the steel. Thus, > depending on how fast or slowly you cool it vs. how non-linear > the conductivity is as a function of temperature, I imagine you > could observe the very effect you describe. > > /tvb > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Tom The thermal conductivity isnt constant with temperature. It also varies between different crystalline forms of the same material. This can be seen in more comprehensive tables of thermal conductivity. In particular at cryogenic temperatures the thermal conductivity can change dramatically (eg in superconductors) Bruce From holrum at hotmail.com Fri Jun 12 00:31:53 2009 From: holrum at hotmail.com (Mark Sims) Date: Fri, 12 Jun 2009 00:31:53 +0000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: Thermal conductivity even varies with the same crystalline forms of the same element. Diamond has the highest known conductivity of any natural substance. Isotopically pure carbon-12 diamond has twice the conductivity of natural diamond. ---------------------------------------- The thermal conductivity isnt constant with temperature. It also varies between different crystalline forms of the same material. _________________________________________________________________ Insert movie times and more without leaving Hotmail?. http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tutorial_QuickAdd_062009 From tvb at LeapSecond.com Fri Jun 12 00:54:56 2009 From: tvb at LeapSecond.com (Tom Van Baak) Date: Thu, 11 Jun 2009 17:54:56 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> Message-ID: <912E4ED1C55040FD88D3908DC71BD0E7@pc52> > Tom > > The thermal conductivity isnt constant with temperature. > It also varies between different crystalline forms of the same material. > This can be seen in more comprehensive tables of thermal conductivity. > In particular at cryogenic temperatures the thermal conductivity can > change dramatically (eg in superconductors) > > Bruce Excellent. Not constant; and perhaps not even linear? If you run across a thermal conductivity table for steel from say 0 to 1000 C let us know. From that graph we should be able to calculate what Rex felt when he put the red hot (1500 F?) end of the 1 inch bar into cold water. Better yet, if some metal or material has an even more pronounced thermal conductivity function it would make a great party trick. /tvb From steveheidmann at yahoo.com Fri Jun 12 01:07:30 2009 From: steveheidmann at yahoo.com (steve heidmann) Date: Thu, 11 Jun 2009 18:07:30 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: <101767.88687.qm@web36802.mail.mud.yahoo.com> How about magnetic effects such as those seen with Galfenol etc. ? ? ?????????????????? Steve --- On Thu, 6/11/09, Tom Van Baak wrote: From: Tom Van Baak Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature To: "Discussion of precise time and frequency measurement" Date: Thursday, June 11, 2009, 5:54 PM > Tom > > The thermal conductivity isnt constant with temperature. > It also varies between different crystalline forms of the same material. > This can be seen in more comprehensive tables of thermal conductivity. > In particular at cryogenic temperatures the thermal conductivity can > change dramatically (eg in superconductors) > > Bruce Excellent. Not constant; and perhaps not even linear? If you run across a thermal conductivity table for steel from say 0 to 1000 C let us know. From that graph we should be able to calculate what Rex felt when he put the red hot (1500 F?) end of the 1 inch bar into cold water. Better yet, if some metal or material has an even more pronounced thermal conductivity function it would make a great party trick. /tvb _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From djl at montana.com Fri Jun 12 01:07:49 2009 From: djl at montana.com (Don Latham) Date: Thu, 11 Jun 2009 19:07:49 -0600 (MDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <912E4ED1C55040FD88D3908DC71BD0E7@pc52> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> Message-ID: <0d04b4b2a1006e13992a72c4c8b64803.squirrel@webmail.montana.com> Thermal conductivity of iron is 0..161 at 18C, and .191 from 100C to 1245C according to my Handbook (conditions are calories per second through a plate 1 cm thick across an area of one sq. cm when the temperature difference is one deg C). Point is, that's only 3 parts per 100, not enough for the crude sensing system employed? Don Latham Tom Van Baak >> Tom >> >> The thermal conductivity isnt constant with temperature. >> It also varies between different crystalline forms of the same material. >> This can be seen in more comprehensive tables of thermal conductivity. >> In particular at cryogenic temperatures the thermal conductivity can >> change dramatically (eg in superconductors) >> >> Bruce > > Excellent. Not constant; and perhaps not even linear? > > If you run across a thermal conductivity table for steel > from say 0 to 1000 C let us know. From that graph we > should be able to calculate what Rex felt when he put the > red hot (1500 F?) end of the 1 inch bar into cold water. > > Better yet, if some metal or material has an even more > pronounced thermal conductivity function it would make > a great party trick. > > /tvb > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com From jfor at quik.com Fri Jun 12 01:09:05 2009 From: jfor at quik.com (J. Forster) Date: Thu, 11 Jun 2009 18:09:05 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <912E4ED1C55040FD88D3908DC71BD0E7@pc52> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> Message-ID: <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> The effect that was described was absolutely NOT a result of thermal conductivity being a function of temperature. It was a dynamic effect... a transient condition. The result of applying a short heat pulse to a long Time Constant, distributed system. Do the simulation I suggested hours ago. -John ============== >> Tom >> >> The thermal conductivity isnt constant with temperature. >> It also varies between different crystalline forms of the same material. >> This can be seen in more comprehensive tables of thermal conductivity. >> In particular at cryogenic temperatures the thermal conductivity can >> change dramatically (eg in superconductors) >> >> Bruce > > Excellent. Not constant; and perhaps not even linear? > > If you run across a thermal conductivity table for steel > from say 0 to 1000 C let us know. From that graph we > should be able to calculate what Rex felt when he put the > red hot (1500 F?) end of the 1 inch bar into cold water. > > Better yet, if some metal or material has an even more > pronounced thermal conductivity function it would make > a great party trick. > > /tvb > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From jfor at quik.com Fri Jun 12 01:10:42 2009 From: jfor at quik.com (J. Forster) Date: Thu, 11 Jun 2009 18:10:42 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: <2137.12.6.201.179.1244769042.squirrel@popacctsnew.quik.com> The effect that was described was absolutely NOT a result of thermal conductivity being a function of temperature. It was a dynamic effect... a transient condition. The result of applying a short heat pulse to a long Time Constant, distributed system. Do the simulation I suggested hours ago. -John ============== >> Tom >> >> The thermal conductivity isnt constant with temperature. >> It also varies between different crystalline forms of the same material. This can be seen in more comprehensive tables of thermal conductivity. In particular at cryogenic temperatures the thermal conductivity can change dramatically (eg in superconductors) >> >> Bruce > > Excellent. Not constant; and perhaps not even linear? > > If you run across a thermal conductivity table for steel > from say 0 to 1000 C let us know. From that graph we > should be able to calculate what Rex felt when he put the > red hot (1500 F?) end of the 1 inch bar into cold water. > > Better yet, if some metal or material has an even more > pronounced thermal conductivity function it would make > a great party trick. > > /tvb > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From rexa at sonic.net Fri Jun 12 01:53:01 2009 From: rexa at sonic.net (Rex) Date: Thu, 11 Jun 2009 18:53:01 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1099.12.6.201.152.1244732453.squirrel@popacctsnew.quik.com> References: <2007.1244707410@critter.freebsd.dk> <1099.12.6.201.152.1244732453.squirrel@popacctsnew.quik.com> Message-ID: <4A31B4FD.30103@sonic.net> J. Forster wrote: >It has nothing to do with this. > >A long (length >> width) bar can simply be modeled as a long ladder of >series resistors's and capacitors to ground: > >---zzz---zzz---zzz---- ... ---zzz--- > _|_ _|_ _|_ _|_ > ___ ___ ___ ___ >----| ----|-----|----- ... ----|----- > >If you put a rectangular pulse in the left end, it will emerge later and >very much rounded at the right end. > >Either do the math or simulate it in Spice or with a handful of R's and >C's and a pulse generator and scope. > >No inductors needed. PERIOD. That model fully accounts for your >observations with the bar heated at one end. > >-John > >================= > > > Ok, but isn't that propagation rate constant? Obviously, the heat from the hot end will eventually propagate with some attenuation to the cold end. My observation was that shoving cold into the hot end seems to accelerate the propagation of heat toward the cold end. This model won't show that effect, will it? This would be a double step something like this: |--- | \ ---| \ ----> + time | / |----| That 2nd opposite step won't make the first pulse propagate faster or with more apparent intensity, will it? -Rex > > > >>In message <4A309B30.7000400 at sonic.net>, Rex writes: >> >> >> >>>My observation, from doing this >>>several times, is that the cold water quickly absorbes heat from the red >>>end, but also seems to chase a lot of the heat quickly up toward the >>>cold end, making the bar rapidly uncomfortable to hold. >>> >>> >>I've seen the effect you describe explained in an article somewhere, >>very likely New Scientist or SciAm about five years ago. >> >>When you rapidly heat or cool metals, very often changes in crystal >>lattice structure is involved some of them resulting in quite drastic >>changes to volume. >> >>Heat is essentially atoms wiggling about, and when you change the >>modes of freedom for the atoms, they may have to wiggle harder. >> >>-- >>Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >>phk at FreeBSD.ORG | TCP/IP since RFC 956 >>FreeBSD committer | BSD since 4.3-tahoe >>Never attribute to malice what can adequately be explained by >>incompetence. >> >>_______________________________________________ >>time-nuts mailing list -- time-nuts at febo.com >>To unsubscribe, go to >>https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>and follow the instructions there. >> >> >> >> > > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > > > From bruce.griffiths at xtra.co.nz Fri Jun 12 01:54:11 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 13:54:11 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> Message-ID: <4A31B543.4000609@xtra.co.nz> John That doesn't appear to reproduce what was claimed to have been observed at all. The input is more like a step function that switches from hot to cold. This allows the simulated bar to reach a steady state temperature distribution before decaying smoothly to a lower temperature. Bruce J. Forster wrote: > The effect that was described was absolutely NOT a result of thermal > conductivity being a function of temperature. > > It was a dynamic effect... a transient condition. The result of applying a > short heat pulse to a long Time Constant, distributed system. > > Do the simulation I suggested hours ago. > > -John > > ============== > > > >>> Tom >>> >>> The thermal conductivity isnt constant with temperature. >>> It also varies between different crystalline forms of the same material. >>> This can be seen in more comprehensive tables of thermal conductivity. >>> In particular at cryogenic temperatures the thermal conductivity can >>> change dramatically (eg in superconductors) >>> >>> Bruce >>> >> Excellent. Not constant; and perhaps not even linear? >> >> If you run across a thermal conductivity table for steel >> from say 0 to 1000 C let us know. From that graph we >> should be able to calculate what Rex felt when he put the >> red hot (1500 F?) end of the 1 inch bar into cold water. >> >> Better yet, if some metal or material has an even more >> pronounced thermal conductivity function it would make >> a great party trick. >> >> /tvb >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From bruce.griffiths at xtra.co.nz Fri Jun 12 02:36:07 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 12 Jun 2009 14:36:07 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31B543.4000609@xtra.co.nz> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> Message-ID: <4A31BF17.9040906@xtra.co.nz> Perhaps the answer is somewhat more prosaic. Radiation and convective losses from the hot end of the bar are significant. In particular the radiative loss is (as a first approximation) proportional to the difference of the 4th powers of the bar temperature and ambient temperature. When one modifies the model to include radiative losses near the hot end that are in effect switched off by cooling then some overshoot can occur at the hand held end of the bar. Bruce Bruce Griffiths wrote: > John > > That doesn't appear to reproduce what was claimed to have been observed > at all. > The input is more like a step function that switches from hot to cold. > This allows the simulated bar to reach a steady state temperature > distribution before decaying smoothly to a lower temperature. > > Bruce > > J. Forster wrote: > >> The effect that was described was absolutely NOT a result of thermal >> conductivity being a function of temperature. >> >> It was a dynamic effect... a transient condition. The result of applying a >> short heat pulse to a long Time Constant, distributed system. >> >> Do the simulation I suggested hours ago. >> >> -John >> >> ============== >> >> >> >> >>>> Tom >>>> >>>> The thermal conductivity isnt constant with temperature. >>>> It also varies between different crystalline forms of the same material. >>>> This can be seen in more comprehensive tables of thermal conductivity. >>>> In particular at cryogenic temperatures the thermal conductivity can >>>> change dramatically (eg in superconductors) >>>> >>>> Bruce >>>> >>>> >>> Excellent. Not constant; and perhaps not even linear? >>> >>> If you run across a thermal conductivity table for steel >>> from say 0 to 1000 C let us know. From that graph we >>> should be able to calculate what Rex felt when he put the >>> red hot (1500 F?) end of the 1 inch bar into cold water. >>> >>> Better yet, if some metal or material has an even more >>> pronounced thermal conductivity function it would make >>> a great party trick. >>> >>> /tvb >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >>> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From namichie at gmail.com Fri Jun 12 03:23:00 2009 From: namichie at gmail.com (Neville Michie) Date: Fri, 12 Jun 2009 13:23:00 +1000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31BF17.9040906@xtra.co.nz> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31BF17.9040906@xtra.co.nz> Message-ID: The problem may be due to the subjectivity of the observer, not a real effect. One dimensional heat flow along a bar will be close to the simple step function in an infinite one dimensional medium. The solution is in the form of Gauss's Error Function, and any cooling can only reduce the rate of progress and/or amplitude of the heat front. Unless heat is added to the cold end of the bar there is no way that it will heat quicker. The radiation can only be switched off by reducing the surface temperature which in turn rapidly reduces the temperature gradient driving the heat front. Thats my 2c worth, Cheers, Neville Michie On 12/06/2009, at 12:36 PM, Bruce Griffiths wrote: > Perhaps the answer is somewhat more prosaic. > > Radiation and convective losses from the hot end of the bar are > significant. > In particular the radiative loss is (as a first approximation) > proportional to the difference of the 4th powers of the bar > temperature > and ambient temperature. > When one modifies the model to include radiative losses near the > hot end > that are in effect switched off by cooling then some overshoot can > occur > at the hand held end of the bar. > > > Bruce > > Bruce Griffiths wrote: >> John >> >> That doesn't appear to reproduce what was claimed to have been >> observed >> at all. >> The input is more like a step function that switches from hot to >> cold. >> This allows the simulated bar to reach a steady state temperature >> distribution before decaying smoothly to a lower temperature. >> >> Bruce >> >> J. Forster wrote: >> >>> The effect that was described was absolutely NOT a result of thermal >>> conductivity being a function of temperature. >>> >>> It was a dynamic effect... a transient condition. The result of >>> applying a >>> short heat pulse to a long Time Constant, distributed system. >>> >>> Do the simulation I suggested hours ago. >>> >>> -John >>> >>> ============== >>> >>> >>> >>> >>>>> Tom >>>>> >>>>> The thermal conductivity isnt constant with temperature. >>>>> It also varies between different crystalline forms of the same >>>>> material. >>>>> This can be seen in more comprehensive tables of thermal >>>>> conductivity. >>>>> In particular at cryogenic temperatures the thermal >>>>> conductivity can >>>>> change dramatically (eg in superconductors) >>>>> >>>>> Bruce >>>>> >>>>> >>>> Excellent. Not constant; and perhaps not even linear? >>>> >>>> If you run across a thermal conductivity table for steel >>>> from say 0 to 1000 C let us know. From that graph we >>>> should be able to calculate what Rex felt when he put the >>>> red hot (1500 F?) end of the 1 inch bar into cold water. >>>> >>>> Better yet, if some metal or material has an even more >>>> pronounced thermal conductivity function it would make >>>> a great party trick. >>>> >>>> /tvb >>>> >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts at febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>>> >>>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/ >>> listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/ >> listinfo/time-nuts >> and follow the instructions there. >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. From pieter.ibelings at gmail.com Fri Jun 12 03:33:34 2009 From: pieter.ibelings at gmail.com (RFSPACE) Date: Thu, 11 Jun 2009 23:33:34 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com><4A31B543.4000609@xtra.co.nz> <4A31BF17.9040906@xtra.co.nz> Message-ID: <1E43903AEDE8490B9EBE0854397A5785@xps630> ----- Original Message ----- From: "Bruce Griffiths" To: "Discussion of precise time and frequency measurement" Sent: Thursday, June 11, 2009 10:36 PM Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature > Perhaps the answer is somewhat more prosaic. > > Radiation and convective losses from the hot end of the bar are > significant. > In particular the radiative loss is (as a first approximation) > proportional to the difference of the 4th powers of the bar temperature > and ambient temperature. > When one modifies the model to include radiative losses near the hot end > that are in effect switched off by cooling then some overshoot can occur > at the hand held end of the bar. > > > Bruce > > Bruce Griffiths wrote: >> John >> >> That doesn't appear to reproduce what was claimed to have been observed >> at all. >> The input is more like a step function that switches from hot to cold. >> This allows the simulated bar to reach a steady state temperature >> distribution before decaying smoothly to a lower temperature. >> >> Bruce >> >> J. Forster wrote: >> >>> The effect that was described was absolutely NOT a result of thermal >>> conductivity being a function of temperature. >>> >>> It was a dynamic effect... a transient condition. The result of applying >>> a >>> short heat pulse to a long Time Constant, distributed system. >>> >>> Do the simulation I suggested hours ago. >>> >>> -John >>> >>> ============== >>> >>> >>> >>> >>>>> Tom >>>>> >>>>> The thermal conductivity isnt constant with temperature. >>>>> It also varies between different crystalline forms of the same >>>>> material. >>>>> This can be seen in more comprehensive tables of thermal conductivity. >>>>> In particular at cryogenic temperatures the thermal conductivity can >>>>> change dramatically (eg in superconductors) >>>>> >>>>> Bruce >>>>> >>>>> >>>> Excellent. Not constant; and perhaps not even linear? >>>> >>>> If you run across a thermal conductivity table for steel >>>> from say 0 to 1000 C let us know. From that graph we >>>> should be able to calculate what Rex felt when he put the >>>> red hot (1500 F?) end of the 1 inch bar into cold water. >>>> >>>> Better yet, if some metal or material has an even more >>>> pronounced thermal conductivity function it would make >>>> a great party trick. >>>> >>>> /tvb >>>> >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts at febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>>> >>>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From pieter.ibelings at gmail.com Fri Jun 12 03:39:41 2009 From: pieter.ibelings at gmail.com (RFSPACE) Date: Thu, 11 Jun 2009 23:39:41 -0400 Subject: [time-nuts] need programmable pulse output References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com><4A31B543.4000609@xtra.co.nz> <4A31BF17.9040906@xtra.co.nz> Message-ID: <3780189875714DABA0BBF1A2C447EDA9@xps630> Hi, I am looking for a GPS module or receiver that has a programmable pulse output in time. I am trying to start two data captures a couple of hundred miles appart for a bistatic RADAR. I need to program the UTC time and maybe the increment when I want the pulses to come out. I am trying to find something relatively cheap before I go layout a board that looks at the NMEA output and gates the 1pps. Thanks, Pieter - N4IP From cfharris at erols.com Fri Jun 12 03:59:28 2009 From: cfharris at erols.com (Chuck Harris) Date: Thu, 11 Jun 2009 23:59:28 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> Message-ID: <4A31D2A0.5070600@erols.com> Tom Van Baak wrote: >> Most people thought it was coincidence of heat propagating up the bar >> just at that time, or steam. Could be, but I still think it is real. >> The cold end of the bar was slowly getting warmer as I carried it, but >> after the sudden cooling of the hot end, the cold end seemed to get >> hot fast. > > Rex, > > We know each material has it's own thermal conductivity. Copper > is 401 W/m-K and steel only about 1/10th that, etc. It would appear > from conductivity tables in books that these are fixed constants. > > But I wonder if near-liquid (red hot) steel has a different (e.g., even > lower) value than warm or cold steel? Is metal thermal conductivity > actually a fixed constant or is it a function of temperature over a > wide range of temperature? > > If so, not only is the temperature changing when you drop the > steel in water, but also the thermal conductivity of the steel. Thus, > depending on how fast or slowly you cool it vs. how non-linear > the conductivity is as a function of temperature, I imagine you > could observe the very effect you describe. Tom, Red hot steel bars are quite far from being molten. They are just black body emitting a more visible light range. It is not until the bar is almost white hot that it is going to melt... generally a very bright yellow. Your bare eyes won't like it! I have heated and held all manner of steel bars in the process of welding and working steel. It always seems to me that it takes about the same amount of time for me to feel the heat. Unlike aluminum, it takes minutes for the heat of a red hot end of a steel bar to travel 2-3 feet and make that end too hot to handle. It always gets there, though. When you stick a bar in water, it lets loose a great burst of steam. The steam is hot enough to burn you quite soundly. Think about this: If your threshold for heat pain is 160F, and the bar is at 130F, how much additional heat does some 500F steam need to your hand add to make your hand uncomfortably hot? I never harden steel in water or oil with a bare hand. Always pliers. Steam does a much better job of burning you than does steel. -Chuck Harris From cfharris at erols.com Fri Jun 12 04:07:05 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 12 Jun 2009 00:07:05 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31B543.4000609@xtra.co.nz> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> Message-ID: <4A31D469.5020600@erols.com> Bruce Griffiths wrote: > John > > That doesn't appear to reproduce what was claimed to have been observed > at all. > The input is more like a step function that switches from hot to cold. > This allows the simulated bar to reach a steady state temperature > distribution before decaying smoothly to a lower temperature. > > Bruce Humans are terrible witnesses when it comes to judging lengths of time, and degrees of temperature. That's probably why clocks and thermometers were invented. -Chuck Harris From cfharris at erols.com Fri Jun 12 04:11:58 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 12 Jun 2009 00:11:58 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31BF17.9040906@xtra.co.nz> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31BF17.9040906@xtra.co.nz> Message-ID: <4A31D58E.4020509@erols.com> Bruce Griffiths wrote: > Perhaps the answer is somewhat more prosaic. > > Radiation and convective losses from the hot end of the bar are significant. > In particular the radiative loss is (as a first approximation) > proportional to the difference of the 4th powers of the bar temperature > and ambient temperature. > When one modifies the model to include radiative losses near the hot end > that are in effect switched off by cooling then some overshoot can occur > at the hand held end of the bar. Yeah, when you dunk the rod in water, the relatively small radiative and convective losses of heat are replaced by a terrifically large conductive loss of heat. The extremely quick cooling is why you dunk the bar in water in the first place. -Chuck Harris From ed_palmer at sasktel.net Fri Jun 12 04:17:55 2009 From: ed_palmer at sasktel.net (Ed Palmer) Date: Thu, 11 Jun 2009 22:17:55 -0600 Subject: [time-nuts] need programmable pulse output In-Reply-To: <3780189875714DABA0BBF1A2C447EDA9@xps630> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31BF17.9040906@xtra.co.nz> <3780189875714DABA0BBF1A2C447EDA9@xps630> Message-ID: <4A31D6F3.70306@sasktel.net> Hi Pieter, Is this what you're looking for? 1PPS TIME OFFSET COMMAND (@@Ay) The GPS receiver outputs a one pulse-per second (1PPS) signal with the rising edge placed on top of the GPS/UTC one second tic mark. The 1PPS Offset command allows the user to offset the 1PPS time mark in one nanosecond increments. This offset can be used to place the 1PPS signal anywhere within the one second epoch. This command is available in the Motorola M12T, M12+, UT+, and VP boards. For more modern boards, the same command is implemented in the I-Lotus M12M and the Navsync CW-25 module with the Motorola firmware load. Be careful if the programmable 10 MHz output on the CW-25 is of interest to you. I bought it last year and at that time it was NOT programmable with the Motorola firmware load. It's fixed at 10 MHz unless you get Navsync to do some custom development. The speed is only programmable with the NMEA firmware load. Ed RFSPACE wrote: > Hi, > > I am looking for a GPS module or receiver that has a programmable > pulse output in time. I am trying to start two data captures a couple > of hundred miles appart for a bistatic RADAR. I need to program the > UTC time and maybe the increment when I want the pulses to come out. I > am trying to find something relatively cheap before I go layout a > board that looks at the NMEA output and gates the 1pps. > > Thanks, > > Pieter - N4IP > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From BNeubig at t-online.de Fri Jun 12 05:24:37 2009 From: BNeubig at t-online.de (Bernd T-Online) Date: Fri, 12 Jun 2009 07:24:37 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1E7D846F9D87455D8DC97FCEC59C775B@pc52> References: <4A312118.5010804@sasktel.net> <1E7D846F9D87455D8DC97FCEC59C775B@pc52> Message-ID: <4A31E695.5020406@t-online.de> Hi Tom, I do have such temperature chambers. I wil do the test with a 10544 and a 10811 over teh comming wekeend probably. Regards Bernd Neubig (DK1AG) __________________ AXTAL GmbH & Co. KG www.axtal.com Tom Van Baak wrote: > Does anyone on the list have access to a low temperature > test chamber? It would be interesting to see how slowly a > 10544 or 10811 warms up from that cold environment as > compared to a more modern and compact E1938 or MTI > or TBolt-style OCXO. From rexa at sonic.net Fri Jun 12 06:57:53 2009 From: rexa at sonic.net (Rex) Date: Thu, 11 Jun 2009 23:57:53 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31D469.5020600@erols.com> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31D469.5020600@erols.com> Message-ID: <4A31FC71.5070106@sonic.net> Chuck Harris wrote: > Bruce Griffiths wrote: > >> John >> >> That doesn't appear to reproduce what was claimed to have been observed >> at all. >> The input is more like a step function that switches from hot to cold. >> This allows the simulated bar to reach a steady state temperature >> distribution before decaying smoothly to a lower temperature. >> >> Bruce > > > Humans are terrible witnesses when it comes to judging lengths of > time, and degrees of temperature. That's probably why clocks and > thermometers were invented. > > -Chuck Harris > When I started this part of the thread I said that one of these days I want to try to make some measurements to see if I can document what I believe I have experienced. A few others seem to think they have experienced the same effect. I won't say that we couldn't possibly be wrong and it is some kind of illusion. The previous time I posted about this (elsewhere) the majority opinion was that I was wrong about what I thought I was experiencing. Before I quit, here's a little bit more info. By the time I carried the bar to the water, the hot end was probably barely red temp or not red at all. When I first noticed it I wasn't trying to suddenly quench the bar, just cool it off. The bar was nearly horizontal and I was passing it under a stream of cold water a bit at a time. It certainly produced steam but the steam never got near my hand and the increasing heat I felt was coming through the steel. I don't believe the steam was moving down the bar much either (possibly transferring the heat I felt.) Because of what I've experienced, now I tend to cool things by applying the water near my hand and working the water toward the hot end. I'll try to not drag this out by posting more on the subject unless I get some supporting data or if there are any specific questions. From magnus at rubidium.dyndns.org Fri Jun 12 08:32:38 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 12 Jun 2009 10:32:38 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31B4FD.30103@sonic.net> References: <2007.1244707410@critter.freebsd.dk> <1099.12.6.201.152.1244732453.squirrel@popacctsnew.quik.com> <4A31B4FD.30103@sonic.net> Message-ID: <4A3212A6.40605@rubidium.dyndns.org> Rex skrev: > J. Forster wrote: > >> It has nothing to do with this. >> >> A long (length >> width) bar can simply be modeled as a long ladder of >> series resistors's and capacitors to ground: >> >> ---zzz---zzz---zzz---- ... ---zzz--- >> _|_ _|_ _|_ _|_ >> ___ ___ ___ ___ >> ----| ----|-----|----- ... ----|----- >> >> If you put a rectangular pulse in the left end, it will emerge later and >> very much rounded at the right end. >> >> Either do the math or simulate it in Spice or with a handful of R's and >> C's and a pulse generator and scope. >> >> No inductors needed. PERIOD. That model fully accounts for your >> observations with the bar heated at one end. >> >> -John >> >> ================= >> >> >> > > Ok, but isn't that propagation rate constant? Obviously, the heat from > the hot end will eventually propagate with some attenuation to the cold > end. My observation was that shoving cold into the hot end seems to > accelerate the propagation of heat toward the cold end. This model won't > show that effect, will it? > > This would be a double step something like this: > > |--- > | \ > ---| \ ----> + time > | / > |----| > > That 2nd opposite step won't make the first pulse propagate faster or > with more apparent intensity, will it? No, you just perceive it to be related. If you had waited it would have happend anyway without the cooling period. Your cooling has nothing to do with the already heated wave. While the speed does depend on temperature, it is not that distinct effect. The cooling will also take that time to get through. Cheers, Magnus From magnus at rubidium.dyndns.org Fri Jun 12 12:56:17 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 12 Jun 2009 14:56:17 +0200 Subject: [time-nuts] GPS Week 1536 causing problems? Message-ID: <4A325071.1090802@rubidium.dyndns.org> Fellow time-nuts, If you recall, when we hit GPS week 1524 (1024 + 500) we had issues with a few receivers that didn't handle their biased GPS week wrapping correctly. Then the arbitrary constant was 500. Now on Sunday the aribtrary constant of 512 occurs as we enter GPS week 1536 (1024 + 512), as calculated here: http://csrc.ucsd.edu/scripts/convertDate.cgi?time=1536+0 If you see any node having problem, it would be nice to know. Hopefully no node fails. Cheers, Magnus From cfharris at erols.com Fri Jun 12 13:02:35 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 12 Jun 2009 09:02:35 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A31FC71.5070106@sonic.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31D469.5020600@erols.com> <4A31FC71.5070106@sonic.net> Message-ID: <4A3251EB.9030502@erols.com> Rex wrote: >> Humans are terrible witnesses when it comes to judging lengths of >> time, and degrees of temperature. That's probably why clocks and >> thermometers were invented. >> >> -Chuck Harris >> > > When I started this part of the thread I said that one of these days I > want to try to make some measurements to see if I can document what I > believe I have experienced. A few others seem to think they have > experienced the same effect. I won't say that we couldn't possibly be > wrong and it is some kind of illusion. The previous time I posted about > this (elsewhere) the majority opinion was that I was wrong about what I > thought I was experiencing. Rex, it isn't that you are wrong about what you thought you were experiencing, it is more that you mis interpreted the result. Time, as perceived by humans is variable. The old saying that time flies when you are having fun, it true from most people's perception. And time crawls when you are focusing on being in a hurry, as is often the case when working with red hot metal. I am certain that if you do the experiment with some more controls, you will discover that, if anything, the heat to your hand slows as a result of cooling the bar (horizontally in water). Here is how I would run an informal experiment: Put two identical bars in the forge fire, and let the ends heat to a nice orange heat. Turn on the water at the sink. Pick one bar up in your left hand, and the other in your right. Walk over to the sink, taking about the amount of time you did before, and hold the end of one bar in the water, and keep the other bar out of the water... and wait for it.... If the bar in the water becomes uncomfortable to hold before the one that is out of the water, you are on to something. I bet it won't. > Before I quit, here's a little bit more info. By the time I carried the > bar to the water, the hot end was probably barely red temp or not red at > all. When I first noticed it I wasn't trying to suddenly quench the bar, > just cool it off. The bar was nearly horizontal and I was passing it > under a stream of cold water a bit at a time. It certainly produced > steam but the steam never got near my hand and the increasing heat I > felt was coming through the steel. I don't believe the steam was moving > down the bar much either (possibly transferring the heat I felt.) The reason I mentioned the steam is when you are quenching a bar for the purpose of hardening it, you invariably dunk it straight down in a bucket of water. The steam can't help but rise up to whatever is holding the bar. > Because of what I've experienced, now I tend to cool things by applying > the water near my hand and working the water toward the hot end. Unless you are hardening the steel, you really shouldn't quench it in water. It tends to really mess with the end result. > I'll try to not drag this out by posting more on the subject unless I > get some supporting data or if there are any specific questions. I truly hope you aren't bothered by our rumination. We clearly are enjoying the subject. Thanks for bringing it up. -Chuck Harris From Brucekareen at aol.com Fri Jun 12 15:14:14 2009 From: Brucekareen at aol.com (Brucekareen at aol.com) Date: Fri, 12 Jun 2009 11:14:14 EDT Subject: [time-nuts] Subject: Thunderbolt Stability and Ambient Temperature Message-ID: This interesting discussion of heat conduction by members of the electronics community brings to mind that in the 1870's, Joseph Fourier, while analyzing the waveform of heat propagating around a metal ring, developed the elegant method of Fourier Analysis. If you have not seen his work and can locate a copy of Fourier's: The Analytical Theory of Heat, you might find it interesting to thumb through it. Bruce Hunter **************Shop Dell?s full line of Laptops now starting at $349! (http://pr.atwola.com/promoclk/100126575x1221881320x1201406166/aol?redir=http:%2F%2 Fad.doubleclick.net%2Fclk%3B215218036%3B37264217%3Bz) From danrae at verizon.net Fri Jun 12 15:48:44 2009 From: danrae at verizon.net (Dan Rae) Date: Fri, 12 Jun 2009 08:48:44 -0700 Subject: [time-nuts] E1938 PIC hex files? Message-ID: <4A3278DC.90405@verizon.net> I am beginning to think that the PIC in my Chinese Ebay 1938 is dead or at least injured. Does anyone have the hex files for this one? Blank PIC16C74As can be had and it may be worth my trying to program a new one. Nothing else seems to make it work and as the PIC seems to be asleep, I'm not sure that attempting to talk to it with the serial program is going to help me much, but I will try. The part number is: E1938-80002 Dan ac6ao From Arnold.Tibus at gmx.de Fri Jun 12 18:37:33 2009 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Fri, 12 Jun 2009 20:37:33 +0200 Subject: [time-nuts] Subject: Thunderbolt Stability and Ambient Temperature In-Reply-To: Message-ID: On Fri, 12 Jun 2009 11:14:14 EDT, Brucekareen at aol.com wrote: >This interesting discussion of heat conduction by members of the >electronics community brings to mind that in the 1870's, Joseph Fourier, while >analyzing the waveform of heat propagating around a metal ring, developed the >elegant method of Fourier Analysis. If you have not seen his work and can >locate a copy of Fourier's: The Analytical Theory of Heat, you might find it >interesting to thumb through it. > >Bruce Hunter >************** A interesting discussion indeed! The Wiedemann-Franz Law may bring more light in this discussion. Gustav Wiedemann and Rudolph Franz found an empirical law of physics, concerning the ratio of the thermal conductivity (K) of a metal to its electrical conductivity (?), being a constant times the absolute temperature. Good and easy to understand descriptions can be found not only in: http://en.wikipedia.org/wiki/Wiedemann-Franz_law http://hyperphysics.phy-astr.gsu.edu/Hbase/thermo/thercond.html enjoy, Arnold From rexa at sonic.net Fri Jun 12 20:17:00 2009 From: rexa at sonic.net (Rex) Date: Fri, 12 Jun 2009 13:17:00 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A3251EB.9030502@erols.com> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31D469.5020600@erols.com> <4A31FC71.5070106@sonic.net> <4A3251EB.9030502@erols.com> Message-ID: <4A32B7BC.5090409@sonic.net> Chuck Harris wrote: > > I truly hope you aren't bothered by our rumination. We clearly are > enjoying the subject. Thanks for bringing it up. > > -Chuck Harris > No, not at all. I brought it up because what I think I saw doesn't make sense from anything I know. I already have a large list of partially-done projects, so I doubt if I'll get back to another look at this subject soon. If I ever do I'll try to post any results. -Rex From mpfahmie at lbl.gov Fri Jun 12 21:42:36 2009 From: mpfahmie at lbl.gov (Mike Fahmie) Date: Fri, 12 Jun 2009 14:42:36 -0700 Subject: [time-nuts] ARRL Summer FMT Announcement Message-ID: <4.2.2.20090612143936.01088ddc@pop.earthlink.net> The ARRL Summer FMT will be held on July 1. See attachment for details. -Mike- WA6ZTY -------------- next part -------------- A non-text attachment was scrubbed... Name: FMT Announcement - 1 July 2009.pdf Type: application/pdf Size: 32321 bytes Desc: not available URL: From had at to-way.com Fri Jun 12 21:46:17 2009 From: had at to-way.com (Had) Date: Fri, 12 Jun 2009 14:46:17 -0700 Subject: [time-nuts] ARRL FMT Message-ID: <20090612214620.549DDD5CAE7@mail-in06.adhost.com> It's that time again. The ARRL Summer FMT will be held on July 1. See attachment for details. -Mike- WA6ZTY FMT Announcement - 1 July 2009.pdf FMT Announcement - 1 July 2009.pdf Had -------------- next part -------------- A non-text attachment was scrubbed... Name: 642800d.jpg Type: image/jpeg Size: 2320 bytes Desc: not available URL: From mccorkle at ptialaska.net Sat Jun 13 06:16:13 2009 From: mccorkle at ptialaska.net (Richard H McCorkle) Date: Fri, 12 Jun 2009 22:16:13 -0800 (AKDT) Subject: [time-nuts] E1938 PIC hex files? In-Reply-To: <4A3278DC.90405@verizon.net> References: <4A3278DC.90405@verizon.net> Message-ID: <23336.206.174.20.67.1244873773.squirrel@mymail.acsalaska.net> Hi Dan, If the 1938 was purchased through Fluke1 he is usually very good about replacing bad items he sells to Time-Nuts. You might want to contact him about a replacement unit or perhaps getting a pre-programmed PIC from a different unit to try. Richard > I am beginning to think that the PIC in my Chinese Ebay 1938 is dead or > at least injured. Does anyone have the hex files for this one? Blank > PIC16C74As can be had and it may be worth my trying to program a new > one. Nothing else seems to make it work and as the PIC seems to be > asleep, I'm not sure that attempting to talk to it with the serial > program is going to help me much, but I will try. > > The part number is: E1938-80002 > > > Dan > > ac6ao > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From robert8rpi at yahoo.co.uk Sat Jun 13 09:29:13 2009 From: robert8rpi at yahoo.co.uk (Robert Atkinson) Date: Sat, 13 Jun 2009 09:29:13 +0000 (GMT) Subject: [time-nuts] E1938 PIC hex files? Message-ID: <982060.46385.qm@web27106.mail.ukl.yahoo.com> Pics have pretty good copy protection. I'd be surprised if Agilent haven't protected the pic in the E1938. Many pics (AFIK thisincludes the 'C74) scramble the data on reading a copy protected chip. This allows the verification of a chip without revealing the code. A known good chip is a starting point. fortuntly HP socketed the PLCC pic. Know you need a time nut with a good E1938, a PicStart Plus ( or similar programmer) and a PLCC adaptor. I have the latter two but no E1938. Robert G8RPI. --- On Sat, 13/6/09, Richard H McCorkle wrote: > From: Richard H McCorkle > Subject: Re: [time-nuts] E1938 PIC hex files? > To: danrae at verizon.net, "Discussion of precise time and frequency measurement" > Date: Saturday, 13 June, 2009, 7:16 AM > Hi Dan, > > If the 1938 was purchased through Fluke1 he is usually very > good > about replacing bad items he sells to Time-Nuts. You might > want > to contact him about a replacement unit or perhaps getting > a > pre-programmed PIC from a different unit to try. > > Richard > > > > I am beginning to think that the PIC in my Chinese > Ebay 1938 is dead or > > at least injured.? Does anyone have the hex files > for this one?? Blank > > PIC16C74As can be had and it may be worth my trying to > program a new > > one.? Nothing else seems to make it work and as > the PIC seems to be > > asleep, I'm not sure that attempting to talk to it > with the serial > > program is going to help me much, but I will try. > > > > The part number is: E1938-80002 > > > > > > Dan > > > > ac6ao > > > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From cfharris at erols.com Sat Jun 13 10:17:10 2009 From: cfharris at erols.com (Chuck Harris) Date: Sat, 13 Jun 2009 06:17:10 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A32B7BC.5090409@sonic.net> References: <20090611020927.9FE07BCEF@ip-64-139-1-69.sjc.megapath.net> <4A309B30.7000400@sonic.net> <0951484A9F6B41A0A98D5F5AFD8D29AC@pc52> <4A319D2D.1000903@xtra.co.nz> <912E4ED1C55040FD88D3908DC71BD0E7@pc52> <2131.12.6.201.179.1244768945.squirrel@popacctsnew.quik.com> <4A31B543.4000609@xtra.co.nz> <4A31D469.5020600@erols.com> <4A31FC71.5070106@sonic.net> <4A3251EB.9030502@erols.com> <4A32B7BC.5090409@sonic.net> Message-ID: <4A337CA6.405@erols.com> Hi Rex, I just did something similar. I was doing some heavy grinding on a 6 inch long rod that was to become a new tool, and as I started to perceive that the rod was getting hot, I dunked the end I was grinding into cool water. And, I almost immediately started to feel the rod, where I was gripping it, cooling down. I am certain that you were just moments away from feeling the heat reach your grip when you decided to cool the rod you were working. It would have gotten to your hand at the same time whether or not you had decided to plunge the rod into water. Even though I don't recall hearing anyone make the same claim as you have, I do have a couple of books on blacksmithing, from the days of yore, that I will skim to see if anyone observed the same effect. -Chuck Harris Rex wrote: > Chuck Harris wrote: > >> >> I truly hope you aren't bothered by our rumination. We clearly are >> enjoying the subject. Thanks for bringing it up. >> >> -Chuck Harris >> > > No, not at all. I brought it up because what I think I saw doesn't make > sense from anything I know. > > I already have a large list of partially-done projects, so I doubt if > I'll get back to another look at this subject soon. If I ever do I'll > try to post any results. > > -Rex From ka2cdk at cox.net Sat Jun 13 17:16:00 2009 From: ka2cdk at cox.net (Thomas A. Frank) Date: Sat, 13 Jun 2009 13:16:00 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> References: <4A30457E.9060701@erols.com> <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> Message-ID: >> I just don't know what to say to that! Even a child can put a >> case of bottled water in a box, and not have it evaporate or leak. >> I would venture that said case of bottled water will still be full >> up when the child graduates from college, and has kids of his own. > > But goodness knows what sort of a biological hazard it will be by > then :-) More to the point, you will be disappointed to find the bottles will NOT last that long. Cleaning out the cupboard recently, I can across some bottled water that had 1998 date codes. Several had leaked, but one was still intact enough to show the likely problem. It would appear that over the past 10 years, the gases dissolved in the water migrated through the plastic (or the cap seal), resulting in a vacuum forming in the bottle. This distended the bottles and caused structural failure. Either that, or the water caused the plastic to shrink. Glass would probably fair better. Tom Frank, KA2CDK From cfharris at erols.com Sat Jun 13 17:35:40 2009 From: cfharris at erols.com (Chuck Harris) Date: Sat, 13 Jun 2009 13:35:40 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: <4A30457E.9060701@erols.com> <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> Message-ID: <4A33E36C.7090008@erols.com> Sigh! I guess the point is still being missed. It isn't hard at all to keep water in a container. The plastic water bottle scenario was created to put the issue into perspective. Perhaps some plastic bottles don't have the staying power to last into the next century, but that doesn't in any way indicate that it is a difficult problem. There are metal cans that have held liquids for centuries. There are glass, and ceramic bottles that have held liquids for thousands of years. Surely if you wanted to use a quantity of water to act as a thermal ballast, or cushion, it would be worth the tiny amount of effort necessary to enclose it? Perhaps something glued up out of Schedule 40 PVC pipe? Or maybe a Nalgene bottle? Or a thick walled LDPE bottle? Even a concrete tank wouldn't be out of the question if you needed a big enough ballast. There are concrete basins that have been holding water for decades. Don't let the fact that water might leak dissuade you from using it as a cheap highly capable thermal ballast. -Chuck Harris Thomas A. Frank wrote: > More to the point, you will be disappointed to find the bottles will NOT > last that long. > > Cleaning out the cupboard recently, I can across some bottled water that > had 1998 date codes. Several had leaked, but one was still intact > enough to show the likely problem. It would appear that over the past > 10 years, the gases dissolved in the water migrated through the plastic > (or the cap seal), resulting in a vacuum forming in the bottle. This > distended the bottles and caused structural failure. > > Either that, or the water caused the plastic to shrink. > > Glass would probably fair better. > > Tom Frank, KA2CDK From jfor at quik.com Sat Jun 13 17:59:04 2009 From: jfor at quik.com (J. Forster) Date: Sat, 13 Jun 2009 10:59:04 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A33E36C.7090008@erols.com> References: <4A30457E.9060701@erols.com> <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> <4A33E36C.7090008@erols.com> Message-ID: <1308.12.6.201.78.1244915944.squirrel@popacctsnew.quik.com> Chuck, I don't dispute that you can contain water in plastic a long time, but, if some does escape it may not matter to the bottle contents, but it could well raise the humidity of the surround w/in a tightly sealed oven/box/enclosure. Electronics does not much like high humidity. -John =========== > Sigh! I guess the point is still being missed. It isn't hard at > all to keep water in a container. The plastic water bottle scenario > was created to put the issue into perspective. Perhaps some plastic > bottles don't have the staying power to last into the next century, > but that doesn't in any way indicate that it is a difficult problem. > > There are metal cans that have held liquids for centuries. There > are glass, and ceramic bottles that have held liquids for thousands > of years. > > Surely if you wanted to use a quantity of water to act as a thermal > ballast, or cushion, it would be worth the tiny amount of effort > necessary to enclose it? Perhaps something glued up out of Schedule > 40 PVC pipe? Or maybe a Nalgene bottle? Or a thick walled LDPE > bottle? Even a concrete tank wouldn't be out of the question if > you needed a big enough ballast. There are concrete basins that > have been holding water for decades. > > Don't let the fact that water might leak dissuade you from using > it as a cheap highly capable thermal ballast. > > -Chuck Harris > > Thomas A. Frank wrote: > >> More to the point, you will be disappointed to find the bottles will NOT >> last that long. >> >> Cleaning out the cupboard recently, I can across some bottled water that >> had 1998 date codes. Several had leaked, but one was still intact >> enough to show the likely problem. It would appear that over the past >> 10 years, the gases dissolved in the water migrated through the plastic >> (or the cap seal), resulting in a vacuum forming in the bottle. This >> distended the bottles and caused structural failure. >> >> Either that, or the water caused the plastic to shrink. >> >> Glass would probably fair better. >> >> Tom Frank, KA2CDK > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From cfharris at erols.com Sat Jun 13 18:14:20 2009 From: cfharris at erols.com (Chuck Harris) Date: Sat, 13 Jun 2009 14:14:20 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1308.12.6.201.78.1244915944.squirrel@popacctsnew.quik.com> References: <4A30457E.9060701@erols.com> <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> <4A33E36C.7090008@erols.com> <1308.12.6.201.78.1244915944.squirrel@popacctsnew.quik.com> Message-ID: <4A33EC7C.1020009@erols.com> Yes, but if it takes 20 years for 1 tsp of water to be lost, I just don't see how that rules out the use of water as a thermal ballast. Water's cheapness and availability in bulk makes it quite attractive for this purpose. If you don't trust plastic, use copper, or stainless steel, or... If man can keep a vacuum in a vacuum tube for 100 years, surely keeping a little water in a bottle or can isn't that hard? Besides, I don't think we were talking about putting the water inside of a crystal oven. We were talking about using water as a thermal ballast to keep the closet/box your standard occupied at a more stable temperature. -Chuck Harris J. Forster wrote: > Chuck, I don't dispute that you can contain water in plastic a long time, > but, if some does escape it may not matter to the bottle contents, but it > could well raise the humidity of the surround w/in a tightly sealed > oven/box/enclosure. Electronics does not much like high humidity. > > -John From james.p.lux at jpl.nasa.gov Sat Jun 13 21:43:29 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sat, 13 Jun 2009 14:43:29 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Message-ID: On 6/13/09 10:16 AM, "Thomas A. Frank" wrote: >>> I just don't know what to say to that! Even a child can put a >>> case of bottled water in a box, and not have it evaporate or leak. >>> I would venture that said case of bottled water will still be full >>> up when the child graduates from college, and has kids of his own. >> >> But goodness knows what sort of a biological hazard it will be by >> then :-) > > > More to the point, you will be disappointed to find the bottles will > NOT last that long. See.. The traditional port in glass bottles will survive for decades, if not centuries. If you're going to get thermal mass for your reference oscillator, and you're going to seal it up a'la the "Cask of Amontillado", at least use something that benefits from the age. Plastic bottle of processed tap water isn't it. {N.B. Amontillado is Sherry, not Port, but same basic idea, same benefit from age; and no, I do not recommend sealing a time-nut in the same area. They get cranky and inefficient.} > > From namichie at gmail.com Sat Jun 13 22:02:35 2009 From: namichie at gmail.com (Neville Michie) Date: Sun, 14 Jun 2009 08:02:35 +1000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A33EC7C.1020009@erols.com> References: <4A30457E.9060701@erols.com> <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> <4A33E36C.7090008@erols.com> <1308.12.6.201.78.1244915944.squirrel@popacctsnew.quik.com> <4A33EC7C.1020009@erols.com> Message-ID: <2AC1C3D2-C1F6-4564-88D1-C07C07194EB7@gmail.com> Hi, Water must have a fairly high figure of merit for thermal buffering. Unfortunately the lists of material properties are inaccurate, have gross errors and are inevitably listed in units such as tons per Degree F per inch per square foot. The tons refer to tons of ice per 24 hours, a good old reliable air condtioning unit. The relevant measures are thermal conductivity, thermal heat capacity, density and thermal diffusivity. Now there is an interesting comparison between copper and aluminium. Copper has a specific heat of 0.09 and aluminium 0.2. (cal/gm C ) Copper has a relative thermal conductivity of 0.918 and aluminium 0.48 Copper has a density of 8.9 and Al 2.7 So the heat capacity of copper is 0.8 and Al 0.54 cal/C/cc when calculated on a volume basis. So water at 1cal/C/cc is better than copper, and twice as good as Aluminium. Where water really wins is on price, and being a liquid it will heat with convective circulation and so be much faster than the solids to reach equilibrium. cheers, Neville Michie On 14/06/2009, at 4:14 AM, Chuck Harris wrote: > Yes, but if it takes 20 years for 1 tsp of water to be lost, I just > don't see how that rules out the use of water as a thermal ballast. > Water's cheapness and availability in bulk makes it quite attractive > for this purpose. > > If you don't trust plastic, use copper, or stainless steel, or... > > If man can keep a vacuum in a vacuum tube for 100 years, surely > keeping a little water in a bottle or can isn't that hard? > > Besides, I don't think we were talking about putting the water inside > of a crystal oven. We were talking about using water as a thermal > ballast to keep the closet/box your standard occupied at a more stable > temperature. > > -Chuck Harris > > J. Forster wrote: >> Chuck, I don't dispute that you can contain water in plastic a >> long time, >> but, if some does escape it may not matter to the bottle contents, >> but it >> could well raise the humidity of the surround w/in a tightly sealed >> oven/box/enclosure. Electronics does not much like high humidity. >> -John > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. From hmurray at megapathdsl.net Sat Jun 13 22:18:16 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Sat, 13 Jun 2009 15:18:16 -0700 Subject: [time-nuts] Time/freq from digital TV Message-ID: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> My radio has many news stories about the end of analog TV. What sort of time or frequency can I get from a digital TV signal? Now that frame buffers are common, does each station use its own master clock? -- These are my opinions, not necessarily my employer's. I hate spam. From rtime at dslextreme.com Sun Jun 14 01:13:13 2009 From: rtime at dslextreme.com (rtime @dslextreme.com) Date: Sat, 13 Jun 2009 18:13:13 -0700 Subject: [time-nuts] Thunderbolt UTC time offset Message-ID: Hi Everyone; I have finally gotten around to getting my Thunderbolt operational. Everything is working just fine but I do have a question. In the Thunderbolt monitor screen and the [Time] window I see that the time is 15 seconds off from my TAC and a little box tells me that the UTC Offset is set to 15 seconds. Why would this offset exist and can I somehow reset it to zero? Best regards, Bob K7HBG PS, Many thanks to Whomever it was that posted the "Receiver Sensitivity " information! From david at davsoft.com.au Sun Jun 14 01:40:39 2009 From: david at davsoft.com.au (David Findlay) Date: Sun, 14 Jun 2009 11:40:39 +1000 Subject: [time-nuts] Hi! Message-ID: <200906141140.40316.david@davsoft.com.au> Hi my name is David and I have a rubidium standard. It's a Efratom 100334-006 and outputs 10mhz. What can I do with it? As I understand it I need to provide it a reference to set it's frequency. I was thinking it'd be cool to build a counter that counts the waves and is thereby a clock. A master clock would be cool. Also a tunable highly accurate frequency generator would be useful to me. Are there designs out there to build homebrew equipment based on this, or should I just chase up something commercial? Thanks, David From die at dieconsulting.com Sun Jun 14 01:54:05 2009 From: die at dieconsulting.com (David I. Emery) Date: Sat, 13 Jun 2009 21:54:05 -0400 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <20090614015405.GA2000@pig.dieconsulting.com> On Sat, Jun 13, 2009 at 03:18:16PM -0700, Hal Murray wrote: > > My radio has many news stories about the end of analog TV. > > What sort of time or frequency can I get from a digital TV signal? > > Now that frame buffers are common, does each station use its own master clock? I don't believe there is any standards grade time or frequency that one can derive from a FCC legal standards conformant ATSC transmission in digital format. There are fairly loose specs for ATSC symbol rate (by time-nuts standards) and carrier frequency - not dead nuts on in any broadcast plant unless someone engineering it really cared for some reason. And nothing in the ATSC stream establishes a precise epoch - the stream consists of 188 byte transport stream packets... sent from a queue when a time slot is available... with no particular discipline that a particular packet be sent at a particular exact time. There is, however, a timing mechanism in MPEG2 TV based on a 27 MHz clock that controls and coordinates video and audio rendering in digital TVs ... and part of this is that some packets carry a timestamp in ticks of this clock (called the PCR) so a receiver can lock its own 27 MHz video timebase to this clock so video frames and audio samples are output at the correct times - mostly relative to each other and the video source, of course, and not any absolute UTC time. Broadcast plant may or may not lock its master 27 MHz PCR reference to a GPSDO or rubidium - there is no requirement to do so. And no particular expectation that some epoch of the PCR clock matches a particular UTC epoch. Likely the choice is to use the OCXO in a house master sync generator or ATSC multiplexer as the reference or use an external clock input from some kind of frequency standard. I suppose there ARE stations that use a decent GPSDO or other high grade frequency source for this... how one knows this is true in any particular case, however, is not clear. Most network broadcast distribution is via satellite, and satellites move around in their box in the sky so any time or frequency derived from satellite downlinked signals is subject to Doppler shifts over the course of a day as the satellite completes its figure eight pattern in the sky (most operational birds are slightly inclined, thus the figure 8 - none are dead nuts on the equator and in perfectly circular orbits). This means that no network timing from a satellite signal is stable by precise metric standards... even if the uplink signal is right on. What all this means in practice is that there is no longer any precise broadcast TV signal that can be depended on as really accurate. Of course this has already been true for at least the past 20 years with analog NTSC transmissions from ubiquitous digital broadcast plant... for the most part the timing for the old analog NTSC transmissions was derived from the OCXO (or even just TCXO) in either a master sync generator or the digital NTSC modulator just before the transmitter modulator analog input... long long gone are the 1970s era days of a completely analog and un frame buffered path between a stable analog terrestrial microwave based link to a master rubidium or cesium network clock in NYC and the input to the transmitter... -- Dave Emery N1PRE/AE, die at dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." From glennmaillist at bellsouth.net Sun Jun 14 01:59:50 2009 From: glennmaillist at bellsouth.net (Glenn Little WB4UIV) Date: Sat, 13 Jun 2009 21:59:50 -0400 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <6.2.3.4.2.20090613215433.034a9520@mail.bellsouth.net> The digital transmitter could have a GPS based frequency reference. I am the CE for a local station (WCIV). We do not use any standard other than what is installed in the transmitter. I have not verified it, but, I think that the UHF transmitter frequency is controlled by an OCXO. I will try and remember to check on this Monday. I do know that our Analog transmitter used an ovenized crystal for frequency control. We were on channel 4. We definitely are not slaved to the network for frequency control. 73 Glenn WB4UIV At 06:18 PM 6/13/2009, you wrote: >My radio has many news stories about the end of analog TV. > >What sort of time or frequency can I get from a digital TV signal? > >Now that frame buffers are common, does each station use its own master clock? > >-- >These are my opinions, not necessarily my employer's. I hate spam. > > > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. From biwa at att.net Sun Jun 14 02:05:20 2009 From: biwa at att.net (Burt I. Weiner) Date: Sat, 13 Jun 2009 19:05:20 -0700 Subject: [time-nuts] DTV frequency reference signals... In-Reply-To: References: Message-ID: <7.0.0.16.2.20090613184845.036bb3f8@att.net> Prior to change, DTV stations that had a first adjacent lower NTSC had to be within 3 Hz of a specific (5+ MHz) offset from that first adjacent lower NTSC's visual carrier in order to prevent interference to the NTSC's chroma. The only practical way to do that was for both stations to lock to GPS and each maintain, by gentlemen's agreement a 1.5 Hz tolerance. Some of the stations required to do this actually did it. In the Los Angeles area there were several that were stable and within 0.1 Hz. This is sufficient for checking or calibrating a service monitor in the field but not nearly tight enough for what we try to accomplish. The pilot signal is a 10 dB spike on the lower edge of the "box" as seen on a spectrum analyzer. Measuring this is like measuring any AM carrier. Now that NTSC analog is gone there is no requirement for anything other than the normal 1000 Hz tolerance of the pilot signal. Some stations may chose to lock or reference to a GPS standard but this is not a requirement. As to what signals may be within the data channel, I have no idea what's there other than a lot of boring programming. Burt, K6OQK >From: Hal Murray >Subject: [time-nuts] Time/freq from digital TV > > > >My radio has many news stories about the end of analog TV. > >What sort of time or frequency can I get from a digital TV signal? > >Now that frame buffers are common, does each station use its own master clock? Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. biwa at att.net K6OQK From die at dieconsulting.com Sun Jun 14 02:08:18 2009 From: die at dieconsulting.com (David I. Emery) Date: Sat, 13 Jun 2009 22:08:18 -0400 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <6.2.3.4.2.20090613215433.034a9520@mail.bellsouth.net> References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> <6.2.3.4.2.20090613215433.034a9520@mail.bellsouth.net> Message-ID: <20090614020818.GB2000@pig.dieconsulting.com> On Sat, Jun 13, 2009 at 09:59:50PM -0400, Glenn Little WB4UIV wrote: > The digital transmitter could have a GPS based frequency reference. > I am the CE for a local station (WCIV). > We do not use any standard other than what is installed in the transmitter. > > I have not verified it, but, I think that the UHF transmitter > frequency is controlled by an OCXO. I'd bet a lot of current digital exciters use a digital synthesizer locked to a reference rather than a special OCXO crystal cut to a particular TV channel frequency. This COULD allow a 10 Mhz in lock to a GPSDO, rubidium or better... I found a couple of the Boston analog stations were very accurately on frequency using my spectrum analyzer signal counter with a 10 MHz GPSDO reference... so some folks somewhere must bother to lock signals. -- Dave Emery N1PRE/AE, die at dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." From stanley_reynolds at yahoo.com Sun Jun 14 02:11:38 2009 From: stanley_reynolds at yahoo.com (Stanley Reynolds) Date: Sat, 13 Jun 2009 19:11:38 -0700 (PDT) Subject: [time-nuts] Hi! In-Reply-To: <200906141140.40316.david@davsoft.com.au> References: <200906141140.40316.david@davsoft.com.au> Message-ID: <572332.32604.qm@web30301.mail.mud.yahoo.com> For a commerical unit : http://www.febo.com/pages/hardware/PTS/ For a clock : http://www.qsl.net/zl1bpu/MICRO/CLOCK/index.htm?(just the first one I came to many more if you google) I have purchased some Time code generators abt $25 to $50 usd including shipping on ebay that will take a external 10 Mhz look here : http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=220423640375 Stanley ----- Original Message ---- From: David Findlay To: time-nuts at febo.com Sent: Saturday, June 13, 2009 8:40:39 PM Subject: [time-nuts] Hi! Hi my name is David and I have a rubidium standard. It's a Efratom 100334-006 and outputs 10mhz. What can I do with it? As I understand it I need to provide it a reference to set it's frequency. I was thinking it'd be cool to build a counter that counts the waves and is thereby a clock. A master clock would be cool. Also a tunable highly accurate frequency generator would be useful to me. Are there designs out there to build homebrew equipment based on this, or should I just chase up something commercial? Thanks, David _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From stanley_reynolds at yahoo.com Sun Jun 14 02:34:42 2009 From: stanley_reynolds at yahoo.com (Stanley Reynolds) Date: Sat, 13 Jun 2009 19:34:42 -0700 (PDT) Subject: [time-nuts] Hi! In-Reply-To: <200906141140.40316.david@davsoft.com.au> References: <200906141140.40316.david@davsoft.com.au> Message-ID: <854663.74144.qm@web30306.mail.mud.yahoo.com> no space after link sorry linked fixed : http://www.qsl.net/zl1bpu/MICRO/CLOCK/index.htm and more abt the same : http://leapsecond.com/pages/atomic-nixie/ Stanley ? ----- Original Message ---- From: David Findlay To: time-nuts at febo.com Sent: Saturday, June 13, 2009 8:40:39 PM Subject: [time-nuts] Hi! Hi my name is David and I have a rubidium standard. It's a Efratom 100334-006 and outputs 10mhz. What can I do with it? As I understand it I need to provide it a reference to set it's frequency. I was thinking it'd be cool to build a counter that counts the waves and is thereby a clock. A master clock would be cool. Also a tunable highly accurate frequency generator would be useful to me. Are there designs out there to build homebrew equipment based on this, or should I just chase up something commercial? Thanks, David _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From darrell at shaw.ca Sun Jun 14 03:06:09 2009 From: darrell at shaw.ca (DARRELL ROBINSON) Date: Sat, 13 Jun 2009 20:06:09 -0700 Subject: [time-nuts] Thunderbolt UTC time offset In-Reply-To: References: Message-ID: A quick search on Google finds (among many)? this short article. http://www.seis.com.au/TechNotes/TN199901A_GPS_UTC.html ----- Original Message ----- From: "rtime @dslextreme.com" Date: Saturday, June 13, 2009 6:13 pm Subject: [time-nuts] Thunderbolt UTC time offset To: time-nuts at febo.com > Hi Everyone; > ?I have finally gotten around to getting my Thunderbolt > operational.Everything is working just fine but I do have a > question. In the Thunderbolt > monitor screen and the [Time] window I see that the time is 15 > seconds off > from my TAC and a little box tells me that the UTC Offset is set > to 15 > seconds. > ?Why would this offset exist and can I somehow reset it to zero? > Best regards, Bob K7HBG > > PS,? Many thanks to Whomever it was that posted the > "Receiver Sensitivity " > information! > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > and follow the instructions there. > From w1ksz at earthlink.net Sun Jun 14 04:33:46 2009 From: w1ksz at earthlink.net (Richard W. Solomon) Date: Sun, 14 Jun 2009 00:33:46 -0400 (EDT) Subject: [time-nuts] Hi! Message-ID: <4369883.1244954026871.JavaMail.root@mswamui-swiss.atl.sa.earthlink.net> Does anyone know where you can find a manual on the TRAK 8500 ? (Time Code Generator) 73, Dick, W1KSZ -----Original Message----- >From: Stanley Reynolds >Sent: Jun 13, 2009 10:11 PM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] Hi! > > >For a commerical unit : http://www.febo.com/pages/hardware/PTS/ > >For a clock : http://www.qsl.net/zl1bpu/MICRO/CLOCK/index.htm?(just the first one I came to many more if you google) > >I have purchased some Time code generators abt $25 to $50 usd including shipping on ebay that will take a external 10 Mhz look here : > >http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=220423640375 > >Stanley > > > >----- Original Message ---- >From: David Findlay >To: time-nuts at febo.com >Sent: Saturday, June 13, 2009 8:40:39 PM >Subject: [time-nuts] Hi! > >Hi my name is David and I have a rubidium standard. It's a Efratom 100334-006 >and outputs 10mhz. What can I do with it? > >As I understand it I need to provide it a reference to set it's frequency. I >was thinking it'd be cool to build a counter that counts the waves and is >thereby a clock. A master clock would be cool. Also a tunable highly accurate >frequency generator would be useful to me. Are there designs out there to >build homebrew equipment based on this, or should I just chase up something >commercial? Thanks, > >David > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. From djl at montana.com Sun Jun 14 06:03:36 2009 From: djl at montana.com (Don Latham) Date: Sun, 14 Jun 2009 00:03:36 -0600 Subject: [time-nuts] Time/freq from digital TV References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> <6.2.3.4.2.20090613215433.034a9520@mail.bellsouth.net> Message-ID: <42BFFE151C0B4E01BD270D14819F0FC4@OFFICE2> Glenn: Please forgive a slight deviation from the time, but do you know what's happening to transmitters in the industry? Thanks very much Don Latham ----- Original Message ----- From: "Glenn Little WB4UIV" To: "Discussion of precise time and frequency measurement" Sent: Saturday, June 13, 2009 7:59 PM Subject: Re: [time-nuts] Time/freq from digital TV > The digital transmitter could have a GPS based frequency reference. > I am the CE for a local station (WCIV). > We do not use any standard other than what is installed in the > transmitter. > > I have not verified it, but, I think that the UHF transmitter frequency is > controlled by an OCXO. > > I will try and remember to check on this Monday. > > I do know that our Analog transmitter used an ovenized crystal for > frequency control. We were on channel 4. > > We definitely are not slaved to the network for frequency control. > > 73 > Glenn > WB4UIV > > > > At 06:18 PM 6/13/2009, you wrote: > >>My radio has many news stories about the end of analog TV. >> >>What sort of time or frequency can I get from a digital TV signal? >> >>Now that frame buffers are common, does each station use its own master >>clock? >> >>-- >>These are my opinions, not necessarily my employer's. I hate spam. >> >> >> >> >>_______________________________________________ >>time-nuts mailing list -- time-nuts at febo.com >>To unsubscribe, go to >>https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From magnus at rubidium.dyndns.org Sun Jun 14 08:41:43 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 14 Jun 2009 10:41:43 +0200 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <20090614015405.GA2000@pig.dieconsulting.com> References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> <20090614015405.GA2000@pig.dieconsulting.com> Message-ID: <4A34B7C7.70302@rubidium.dyndns.org> David I. Emery skrev: > Most network broadcast distribution is via satellite, and > satellites move around in their box in the sky so any time or frequency > derived from satellite downlinked signals is subject to Doppler shifts > over the course of a day as the satellite completes its figure eight > pattern in the sky (most operational birds are slightly inclined, thus > the figure 8 - none are dead nuts on the equator and in perfectly > circular orbits). This means that no network timing from a satellite > signal is stable by precise metric standards... even if the uplink signal > is right on. > > What all this means in practice is that there is no longer any > precise broadcast TV signal that can be depended on as really accurate. You are correct, until the time when an ATSC network is operated in Single Frequency Network (SFN) mode, in which case the transmitter signals is coordinated with the aid of GPS receivers. The ATSC SFN specs is in a separate document. As I recalled it when I fast read it a few years back was that it seemed like they had made a few thought errors which caused overspecing but still possible. Cheers, Magnus From rexa at sonic.net Sun Jun 14 10:15:47 2009 From: rexa at sonic.net (Rex) Date: Sun, 14 Jun 2009 03:15:47 -0700 Subject: [time-nuts] Hi! In-Reply-To: <200906141140.40316.david@davsoft.com.au> References: <200906141140.40316.david@davsoft.com.au> Message-ID: <4A34CDD3.3040605@sonic.net> David Findlay wrote: >Hi my name is David and I have a rubidium standard. > Sounds like a T-N A meeting. (Time-Nuts Anonymous.) :-) From sar10538 at gmail.com Sun Jun 14 10:33:21 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Sun, 14 Jun 2009 22:33:21 +1200 Subject: [time-nuts] Hi! In-Reply-To: <4A34CDD3.3040605@sonic.net> References: <200906141140.40316.david@davsoft.com.au> <4A34CDD3.3040605@sonic.net> Message-ID: <1231b6a80906140333h324296e1r6d03aa2b25c18869@mail.gmail.com> 2009/6/14 Rex : > David Findlay wrote: > >> Hi my name is David and I have a rubidium standard. >> > > Sounds like a T-N A meeting. (Time-Nuts Anonymous.) > :-) Thanks Rex, haven't laughed so loud in a long time! > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From alan.melia at btinternet.com Sun Jun 14 01:03:22 2009 From: alan.melia at btinternet.com (Alan Melia) Date: Sun, 14 Jun 2009 02:03:22 +0100 Subject: [time-nuts] Time/freq from digital TV References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <000401c9ece2$a3b6ccc0$0900a8c0@AM> This may not relate to the USA but a couple of years back I had an interesting chat with a BBC engineer at an NPL Time and Frequency gathering at Teddington. His comment was along the lines of....."....well there is as you realise not need to sync lines and frames nationally now because all the network content travels digitally even though we have only just started a phased change-over. The frames and line syncs broadcast will be probably derived from a "good clock" but it will not be a single traceable unit as it was. There is no telling how good the clock is, though it will probably be better than absolutely necesary. Alan G3NYK ----- Original Message ----- From: "Hal Murray" To: Sent: Saturday, June 13, 2009 11:18 PM Subject: [time-nuts] Time/freq from digital TV > > My radio has many news stories about the end of analog TV. > > What sort of time or frequency can I get from a digital TV signal? > > Now that frame buffers are common, does each station use its own master clock? > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From magnus at rubidium.dyndns.org Sun Jun 14 11:31:39 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 14 Jun 2009 13:31:39 +0200 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <000401c9ece2$a3b6ccc0$0900a8c0@AM> References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net> <000401c9ece2$a3b6ccc0$0900a8c0@AM> Message-ID: <4A34DF9B.4010306@rubidium.dyndns.org> Alan Melia skrev: > This may not relate to the USA but a couple of years back I had an > interesting chat with a BBC engineer at an NPL Time and Frequency gathering > at Teddington. His comment was along the lines of....."....well there is as > you realise not need to sync lines and frames nationally now because all the > network content travels digitally even though we have only just started a > phased change-over. The frames and line syncs broadcast will be probably > derived from a "good clock" but it will not be a single traceable unit as it > was. There is no telling how good the clock is, though it will probably be > better than absolutely necesary. Actually, this is still far from the thinking I have heard from other sources. They essentially want everything traceable to TAI/UTC. Digital doesn't help, it makes it more acute actually. Cheers, Magnus From alan.melia at btinternet.com Sun Jun 14 12:07:06 2009 From: alan.melia at btinternet.com (Alan Melia) Date: Sun, 14 Jun 2009 13:07:06 +0100 Subject: [time-nuts] Time/freq from digital TV References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net><000401c9ece2$a3b6ccc0$0900a8c0@AM> <4A34DF9B.4010306@rubidium.dyndns.org> Message-ID: <001201c9ece8$b5e325a0$0900a8c0@AM> Hi Magnus that may be the case in some countries I suppose. Surely the accuracy is only required at the end of the transmission link, the frames from different sources are then resynchronised, and it is not "necessary" to transmit nationwide accurately synced frames?? The UK is "privatised" and content distribution network and transmitters are no longer owned by the programme companies, and they probably have little say in this aspect except that it will depend upon the price they are willing to pay.......... hence the BBC engineer did not think it a "reliable form of frequency distribution in the UK"....this does not mean it might not be useful! Alan ----- Original Message ----- From: "Magnus Danielson" To: "Discussion of precise time and frequency measurement" Sent: Sunday, June 14, 2009 12:31 PM Subject: Re: [time-nuts] Time/freq from digital TV > Alan Melia skrev: > > This may not relate to the USA but a couple of years back I had an > > interesting chat with a BBC engineer at an NPL Time and Frequency gathering > > at Teddington. His comment was along the lines of....."....well there is as > > you realise not need to sync lines and frames nationally now because all the > > network content travels digitally even though we have only just started a > > phased change-over. The frames and line syncs broadcast will be probably > > derived from a "good clock" but it will not be a single traceable unit as it > > was. There is no telling how good the clock is, though it will probably be > > better than absolutely necesary. > > Actually, this is still far from the thinking I have heard from other > sources. They essentially want everything traceable to TAI/UTC. > > Digital doesn't help, it makes it more acute actually. > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From phk at phk.freebsd.dk Sun Jun 14 12:39:03 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Sun, 14 Jun 2009 12:39:03 +0000 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: Your message of "Sun, 14 Jun 2009 13:31:39 +0200." <4A34DF9B.4010306@rubidium.dyndns.org> Message-ID: <45228.1244983143@critter.freebsd.dk> In message <4A34DF9B.4010306 at rubidium.dyndns.org>, Magnus Danielson writes: >Alan Melia skrev: >Actually, this is still far from the thinking I have heard from other >sources. They essentially want everything traceable to TAI/UTC. Make sure you ask an exact question. For source material, they are very keen on traceability. On the transmission side they don't care much because the network delay these days can approach tens of seconds... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From magnus at rubidium.dyndns.org Sun Jun 14 12:41:34 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 14 Jun 2009 14:41:34 +0200 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <001201c9ece8$b5e325a0$0900a8c0@AM> References: <20090613221817.BF61BBCEF@ip-64-139-1-69.sjc.megapath.net><000401c9ece2$a3b6ccc0$0900a8c0@AM> <4A34DF9B.4010306@rubidium.dyndns.org> <001201c9ece8$b5e325a0$0900a8c0@AM> Message-ID: <4A34EFFE.4030507@rubidium.dyndns.org> Hi Alan, Alan Melia wrote: > Hi Magnus that may be the case in some countries I suppose. Surely the > accuracy is only required at the end of the transmission link, the frames > from different sources are then resynchronised, and it is not "necessary" to > transmit nationwide accurately synced frames?? The UK is "privatised" and > content distribution network and transmitters are no longer owned by the > programme companies, and they probably have little say in this aspect except > that it will depend upon the price they are willing to pay.......... hence > the BBC engineer did not think it a "reliable form of frequency distribution > in the UK"....this does not mean it might not be useful! > Already in the production phase over contribution networks, avoiding frame stores is what you want. In one example a feed across Europe included 4 frame stores. As for SFN networks, from the SFN adapter you want propper timing to all receivers and SFN adapters. If you have one mux being national, that mux needs the good timing throughout the whole national network, unless you ignore SFN properties in some areas. You don't framestore in the distribution phase, it's already encoded and everything. The flat TV screens people now have also include frame stores, causing headaches... I'll stick to my fatscreen a little while longer. Framestores should only be used with care, they solve stupid problems but lowers the quality. Anyway, the assumption that timing is being fucked up locally with DTV is just not necesserilly correct. In the SFN world it is quite the opposite actually. However, the development has enabled lower and lower achieved qualities to be accepted, while everyone has had to invest again. Great deal, isn't it? Cheers, Magnus From magnus at rubidium.dyndns.org Sun Jun 14 12:47:47 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 14 Jun 2009 14:47:47 +0200 Subject: [time-nuts] Time/freq from digital TV In-Reply-To: <45228.1244983143@critter.freebsd.dk> References: <45228.1244983143@critter.freebsd.dk> Message-ID: <4A34F173.9050302@rubidium.dyndns.org> Poul-Henning Kamp skrev: > In message <4A34DF9B.4010306 at rubidium.dyndns.org>, Magnus Danielson writes: >> Alan Melia skrev: > >> Actually, this is still far from the thinking I have heard from other >> sources. They essentially want everything traceable to TAI/UTC. > > Make sure you ask an exact question. > > For source material, they are very keen on traceability. > > On the transmission side they don't care much because the network > delay these days can approach tens of seconds... > They do care for transmitters... and SFN. Actually, network based stuff they also care... but for other reasons. Cheers, Magnus From stanley_reynolds at yahoo.com Sun Jun 14 16:19:18 2009 From: stanley_reynolds at yahoo.com (Stanley Reynolds) Date: Sun, 14 Jun 2009 09:19:18 -0700 (PDT) Subject: [time-nuts] Lady Heather DOS version Message-ID: <19708.37814.qm@web30308.mail.mud.yahoo.com> I can find the win32 version aka "setup.exe" but looking for the dos version for 800/600 screen version have an old Compaq laptop. I would be glad to host files for both versions if that is OK. Stanley From jmiles at pop.net Sun Jun 14 22:55:22 2009 From: jmiles at pop.net (John Miles) Date: Sun, 14 Jun 2009 15:55:22 -0700 Subject: [time-nuts] Lady Heather DOS version In-Reply-To: <19708.37814.qm@web30308.mail.mud.yahoo.com> Message-ID: The DOS version is also included with the Win32 distribution at http://www.ke5fx.com/heather/setup.exe . It's called heathdos.exe, and will appear in your installation directory after running the setup program. (Of course the setup program itself has to run under Windows, but if that's a problem I can upload heathdos.exe to the same http directory.) -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Stanley Reynolds > Sent: Sunday, June 14, 2009 9:19 AM > To: time-nuts at febo.com > Subject: [time-nuts] Lady Heather DOS version > > > > I can find the win32 version aka "setup.exe" but looking for the > dos version for 800/600 screen version have an old Compaq laptop. > I would be glad to host files for both versions if that is OK. > > Stanley > From stanley_reynolds at yahoo.com Sun Jun 14 23:10:56 2009 From: stanley_reynolds at yahoo.com (Stanley Reynolds) Date: Sun, 14 Jun 2009 16:10:56 -0700 (PDT) Subject: [time-nuts] Lady Heather DOS version In-Reply-To: References: Message-ID: <44259.36486.qm@web30305.mail.mud.yahoo.com> Thanks, no problem I'm sure one of my neighbors has a windows PC ... just kidding this PC is windows. Stanley ----- Original Message ---- From: John Miles To: Discussion of precise time and frequency measurement Sent: Sunday, June 14, 2009 5:55:22 PM Subject: Re: [time-nuts] Lady Heather DOS version The DOS version is also included with the Win32 distribution at http://www.ke5fx.com/heather/setup.exe .? It's called heathdos.exe, and will appear in your installation directory after running the setup program.? (Of course the setup program itself has to run under Windows, but if that's a problem I can upload heathdos.exe to the same http directory.) -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Stanley Reynolds > Sent: Sunday, June 14, 2009 9:19 AM > To: time-nuts at febo.com > Subject: [time-nuts] Lady Heather DOS version > > > > I can find the win32 version aka "setup.exe" but looking for the > dos version for 800/600 screen version have an old Compaq laptop. > I would be glad to host files for both versions if that is OK. > > Stanley > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From didier at cox.net Mon Jun 15 00:30:28 2009 From: didier at cox.net (Didier Juges) Date: Sun, 14 Jun 2009 19:30:28 -0500 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: <4A30457E.9060701@erols.com><1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> Message-ID: <27AAE3A7805F4D90BC2CD724A5D7AB06@d400> Here in Florida, we routinely store water in prevision of the next big one. Plastic water bottles (any brand) start looking funny (shrunk) after a few months, and downright scary (as in: you don't want to drink from THAT) after a year or so. It seems the gallon jugs do somewhat better than the smaller bottles. I had jugs that still looked OK after a year, but not good after two. The pastic seems much thicker, and maybe it slows down the process? It's been like that for as long as I have lived here, i.e. since 1985. I do not know if it is related to the climate. It makes no appreciable difference if the water is stored in the garage (no A/C) or in the house. Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Thomas A. Frank > Sent: Saturday, June 13, 2009 12:16 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature > > More to the point, you will be disappointed to find the bottles will > NOT last that long. > > Cleaning out the cupboard recently, I can across some bottled water > that had 1998 date codes. Several had leaked, but one was still > intact enough to show the likely problem. It would appear that over > the past 10 years, the gases dissolved in the water migrated through > the plastic (or the cap seal), resulting in a vacuum forming in the > bottle. This distended the bottles and caused structural failure. > > Either that, or the water caused the plastic to shrink. > > Glass would probably fair better. > > Tom Frank, KA2CDK > From masondg44 at comcast.net Mon Jun 15 01:01:29 2009 From: masondg44 at comcast.net (Dave M) Date: Sun, 14 Jun 2009 21:01:29 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: This water thing is getting kinda funny. The loss of water from small plastic bottles is much more likely to be from the screw cap-bottle interface than by leakage through the plastic. It's just a hard plastic to hard plastic interface, with no soft gasket in there to completely fill the voids and make a more complete seal. That's the reason the large jugs hold their water for very long periods of time; they have a gasket under the cap. That's also the reason that you see full bottles of Coke at antique shops and flea markets... they have effective gaskets under the caps to hold the pressure and the contents. Let's move on from this water evaporation mystery?? Dave M masondg44 at comcast dot net One good thing about Alzheimer's; you get to meet new people every day. > Here in Florida, we routinely store water in prevision of the next big > one. > > Plastic water bottles (any brand) start looking funny (shrunk) after a few > months, and downright scary (as in: you don't want to drink from THAT) > after > a year or so. > > It seems the gallon jugs do somewhat better than the smaller bottles. I > had > jugs that still looked OK after a year, but not good after two. The pastic > seems much thicker, and maybe it slows down the process? > > It's been like that for as long as I have lived here, i.e. since 1985. I > do > not know if it is related to the climate. It makes no appreciable > difference > if the water is stored in the garage (no A/C) or in the house. > > Didier KO4BB From david.bengtson at gmail.com Mon Jun 15 01:02:16 2009 From: david.bengtson at gmail.com (David Bengtson) Date: Sun, 14 Jun 2009 21:02:16 -0400 Subject: [time-nuts] test mailing from a new member Message-ID: If this had been a real message, there would have been content here. From Leigh at WA5ZNU.org Mon Jun 15 06:21:04 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr WA5ZNU) Date: Sun, 14 Jun 2009 23:21:04 -0700 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: References: Message-ID: <4A35E850.20202@WA5ZNU.org> For reference, Ridge Equipment has a photo of one of this year's crop of FE-5680A mounted to a large aluminum plate. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330233071735 http://i43.tinypic.com/126cpcp.jpg Leigh/WA5ZNU > Almost all rubidium standards DO specify the use of some form of a heat sink. For the FRK and M100 units this can be a heat sink with around 1" fins or just bolted to a metal plate or chassis. > > The military freq standard that had M100's in them had the unit mounted to a 5x5x.2" aluminum plate that was in turn bolted to the chassis. My Efratom PTB-100 time bases for the Tektronix TM500 mainframes have a large heat sink mounted to a FRK style oscillator. > > LPROs are supposed to be mounted to a metal chassis (they usually come with a thermal pad attached to them). I have seen them lose lock in free air. I saw one mounted in a piece of cell phone equipment. It was bolted to a large heat sink that formed most of the front of the enclosure. > > I have also seen FE-5680A's in their native habitat (again, cell phone equipment). They were mounted to a thick (1/8"?) PCB around 6x16". The side of the PCB that the 5680 was bolted to had a solid ground plane. The 5650A's had one side bolted to a metal chassis. > > ---------------------------------------- > > > _________________________________________________________________ > Hotmail? has ever-growing storage! Don?t worry about storage limits. > http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From hmurray at megapathdsl.net Mon Jun 15 06:43:19 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Sun, 14 Jun 2009 23:43:19 -0700 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: Message from "Leigh L. Klotz, Jr WA5ZNU" of "Sun, 14 Jun 2009 23:21:04 PDT." <4A35E850.20202@WA5ZNU.org> Message-ID: <20090615064320.C6714BCEF@ip-64-139-1-69.sjc.megapath.net> Leigh at WA5ZNU.org said: > For reference, Ridge Equipment has a photo of one of this year's crop > of FE-5680A mounted to a large aluminum plate. > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330233071735 > http://i43.tinypic.com/126cpcp.jpg Is that an aluminum plate or the top side of a PCB used as a heat sink? To me, the first picture looks green/FR4 around the edges. (and a stripe on the left) -- These are my opinions, not necessarily my employer's. I hate spam. From rexa at sonic.net Mon Jun 15 07:32:50 2009 From: rexa at sonic.net (Rex) Date: Mon, 15 Jun 2009 00:32:50 -0700 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: <20090615064320.C6714BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090615064320.C6714BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A35F922.7030601@sonic.net> Hal Murray wrote: >Leigh at WA5ZNU.org said: > > >>For reference, Ridge Equipment has a photo of one of this year's crop >>of FE-5680A mounted to a large aluminum plate. >>http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330233071735 >>http://i43.tinypic.com/126cpcp.jpg >> >> > >Is that an aluminum plate or the top side of a PCB used as a heat sink? > >To me, the first picture looks green/FR4 around the edges. (and a stripe on >the left) > > > Yes, that is a portion of the board I described in an earlier message. The board is thick fiberglass plated heavily on both the top and bottom. The board in the picture has been cut both above and below the 5680A. The plating ended about where the lower cut is, but the plating continued farther above the top of the unit in the picture. My earlier message gave the dimensions. One minor note about this board. The screws holding the 5680 to the borad were an unusual type. I can't remember, I think they may have been a square drive. They were difficult to remove as I had no proper tool to unscrew them. I think I made something from steel rod to start them losening. From magnus at rubidium.dyndns.org Mon Jun 15 09:23:18 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Mon, 15 Jun 2009 11:23:18 +0200 Subject: [time-nuts] test mailing from a new member In-Reply-To: References: Message-ID: <4A361306.70302@rubidium.dyndns.org> Hej David! David Bengtson skrev: > If this had been a real message, there would have been content here. Assuming there had been a real message there, like a presentation of you, what would it say? Cheers, Magnus From dave at uk-ar.co.uk Mon Jun 15 09:44:31 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Mon, 15 Jun 2009 10:44:31 +0100 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: Message-ID: Hi All... Some interesting semi off topic discussions of late, very interesting. Re the water in plastic bottle problem. (I seem not to have seen the original message, there again we've had transient email/isp problems here recently) A "Vacuum" formed by any migration of the contents will not distend (expand) a bottle, but will cause it to collapse in on itself. Water and plastic container combinations in general can be interesting, if just due to the process of Osmosis, dependant on the contents and container materials. (Ask any owner of an elderly GRP boat about that!) Water and some metal combinations are known problem points too, unless you use extremely pure water and choose your metal (and closure methods) carefully. I also suspect a good quantity of light grade synthetic or silicone based oil would do almost as well, and be electrically inert and not react with the container or the materials used in the electronics, so long as the exact material used was chosen with care. However, it will take a system much longer to reach thermal equilibrium, the larger the thermal mass it has. Or as someone else suggested, use a Glass container. So long as you don't want it to last for many 100's of years, as Glass is not a solid, it is a "super cooled fluid" and as such it flows like Ice over time, just that it takes much much longer to do so! Oh, and make sure it has some thermal expansion relief (a gas pocket or an intentional "mechanical soft spot") Just a thought. I remember hearing of a UK amateur many years ago, who had a remote tuneable VFO for (I think for 80mtrs) buried some feet underground in his garden, to achieve thermal and frequency stability. And that was using Valve (Tube) technology too! It was powered 24/7 of course, but I do not know any other details. However, it was said that his signal was one of the most stable (frequency wise at least) on the band in those days (the 70's if not the 60's) I do not know how it was remotely tuned, and it's not exactly a portable solution either! Regards to all. Dave B. From sar10538 at gmail.com Mon Jun 15 10:57:13 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Mon, 15 Jun 2009 22:57:13 +1200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <27AAE3A7805F4D90BC2CD724A5D7AB06@d400> References: <4A30457E.9060701@erols.com> <1231b6a80906102351i5f894967laccd26e73cc8bf63@mail.gmail.com> <27AAE3A7805F4D90BC2CD724A5D7AB06@d400> Message-ID: <1231b6a80906150357g4b89deeewd4cad3e239d8e13a@mail.gmail.com> They suggest you add a small amount of chlorine bleach to water containers you store for natural disaster emergencies. You also need to replace the water on a regular basis even with the bleach in it. Here in Christchurch, New Zealand, they don't even chlorinate the water we drink, it comes straight out of a natural aquifer underneath us. As for the long term effects of bleach on plastic bottles, one would imagine that it would accelerate the breakdown of the plastic. Interestingly, someone in the know, talking about land-fill sites, suggested that there is essentially no breakdown of these items when they are fully embeded in the fill. Luckily we recycle almost everything here but it would make interesting finds for future archaeologists. A glass vessel with a stabilised rubber stopper or lapped glass stopper and wax sealed would seemingly be better for long term use and the glass should conduct the heat better than plastic for our xtal oven ballast. But glass is not a solid, it's a liquid after all and would eventually find the lowest point with time. Mind you, that is a very long time. The other thing that comes to mind is that state-change salt type of liquid that absorbs energy well. Of course, you could use an eskey if it was not holding the beer and may be a less smelly alternative than a used fridge at room temp. 73, Steve 2009/6/15 Didier Juges : > Here in Florida, we routinely store water in prevision of the next big one. > > Plastic water bottles (any brand) start looking funny (shrunk) after a few > months, and downright scary (as in: you don't want to drink from THAT) after > a year or so. > > It seems the gallon jugs do somewhat better than the smaller bottles. I had > jugs that still looked OK after a year, but not good after two. The pastic > seems much thicker, and maybe it slows down the process? > > It's been like that for as long as I have lived here, i.e. since 1985. I do > not know if it is related to the climate. It makes no appreciable difference > if the water is stored in the garage (no A/C) or in the house. > > Didier KO4BB > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Thomas A. Frank >> Sent: Saturday, June 13, 2009 12:16 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature >> >> More to the point, you will be disappointed to find the bottles will >> NOT last that long. >> >> Cleaning out the cupboard recently, I can across some bottled water >> that had 1998 date codes. ?Several had leaked, but one was still >> intact enough to show the likely problem. ?It would appear that over >> the past 10 years, the gases dissolved in the water migrated through >> the plastic (or the cap seal), resulting in a vacuum forming in the >> bottle. ?This distended the bottles and caused structural failure. >> >> Either that, or the water caused the plastic to shrink. >> >> Glass would probably fair better. >> >> Tom Frank, KA2CDK >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From sar10538 at gmail.com Mon Jun 15 11:10:15 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Mon, 15 Jun 2009 23:10:15 +1200 Subject: [time-nuts] test mailing from a new member In-Reply-To: References: Message-ID: <1231b6a80906150410x455c1278x381a2c30e831cf83@mail.gmail.com> 2009/6/15 David Bengtson : > If this had been a real message, there would have been content here. If there had been a real message, there would have been a reply here :-) > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From jltran at worldnet.att.net Mon Jun 15 12:54:26 2009 From: jltran at worldnet.att.net (J. L. Trantham) Date: Mon, 15 Jun 2009 07:54:26 -0500 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: <4A35F922.7030601@sonic.net> Message-ID: <523D7924D3114D1F9CB8F42F9C94955B@S0028384766> They look like Torx Screws. Not so? Thanks, Joe -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Rex Sent: Monday, June 15, 2009 2:33 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A thermal management Hal Murray wrote: >Leigh at WA5ZNU.org said: > > >>For reference, Ridge Equipment has a photo of one of this year's crop >>of FE-5680A mounted to a large aluminum plate. >>http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330233071735 >>http://i43.tinypic.com/126cpcp.jpg >> >> > >Is that an aluminum plate or the top side of a PCB used as a heat sink? > >To me, the first picture looks green/FR4 around the edges. (and a >stripe on >the left) > > > Yes, that is a portion of the board I described in an earlier message. The board is thick fiberglass plated heavily on both the top and bottom. The board in the picture has been cut both above and below the 5680A. The plating ended about where the lower cut is, but the plating continued farther above the top of the unit in the picture. My earlier message gave the dimensions. One minor note about this board. The screws holding the 5680 to the borad were an unusual type. I can't remember, I think they may have been a square drive. They were difficult to remove as I had no proper tool to unscrew them. I think I made something from steel rod to start them losening. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From dave at uk-ar.co.uk Mon Jun 15 13:07:44 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Mon, 15 Jun 2009 14:07:44 +0100 Subject: [time-nuts] Thunderbolts, time references, NTP etc. In-Reply-To: Message-ID: Is this good value, and a trusted seller? I went looking for "Fluke1" as listed earlier on here for these devices (Thunderbolt GPS disciplined referenced sources) but though I (eventually) found the user, no activity was shown for some time. So, I went looking for the product instead, and found (among other things) this item 170344432395 (you know where to look.) My intended main application, is to drive a local NTP server (Network Time Protocol) as I'm getting more and more P'd off with my ISP's ineptitude in maintaining a network where NTP (or anything else not related to web crawling or email) works with any reliability. (Huge and variable latency, ping to ping, at different times of day, confirmed by other users of the same ISP.) I run (just because I can!) a HF beacon monitor station, running the Faros software from Alex VE3NEA. That uses NTP and only NTP to synchronise it's software clock. (http://www.dxatlas.com/Faros/) The results of that can be seen at http://g8kbv.homeip.net:8008/ The white delay spots illustrate where the NTP source is messed up. The 10MHz output would perhaps be useful, once I have modified a radio or two to use that as a reference for their synthesizers, but that is not necessary as yet. I had a GPS with a 1pps output, but due to a PSU malfunction, it doesnt work any more sadly. :-( Mind you, I'm, still having difficulty configuring a FreeBSD box for NTP server use. The instructions to do so I have are good it seems (http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm) just that the system does not seem to co-operate, and I'm not that familiar with Linux/FreeBSD etc at the basic user level, let alone re-compiling the kernel. As evidenced by a non booting system, the two times I eventually got it to compile (that takes hours to complete) and that was not even with modified sources, just what came on the CD unmolested. As each reload takes an age, I sort of lost the plot with that method! The local Linux User Group is not that much help either, no one has any experience with this sort of "engineering" thing. Ultimately, I'd like to run something like this on a non-PC hardware platform. Does anyone on this list know of a ready to run appliance, or preconfigured boot CD of this sort? Providing a LAN NTP source from GPS, for not much more than the cost of one of the Thunderbolts or similar? There are lots of commercial offerings, but way outside my price budget, this is for a hobby after all. Changing ISP would be a hassle, and there is no garantee that any other ISP wouldnt do the same silly thing, seemingly throttling private users WAN traffic during the day, though they say they don't. The ISP support people didnt even know what NTP was when I contacted them, then said that so long as there were no lost packets, ping delays of up to 250ms were acceptable!! Half the trouble seems to be, as a result of them appearing to now be running their NTP servers on the same machines as their border gateway systems, based on IP addresses and service names. Ideas anyone? Regards. Dave B. G0WBX. From ed_palmer at sasktel.net Mon Jun 15 15:28:35 2009 From: ed_palmer at sasktel.net (Ed Palmer) Date: Mon, 15 Jun 2009 09:28:35 -0600 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: <523D7924D3114D1F9CB8F42F9C94955B@S0028384766> References: <523D7924D3114D1F9CB8F42F9C94955B@S0028384766> Message-ID: <4A3668A3.50206@sasktel.net> No. I have one and it's very appropriate for a piece of Time-Nut equipment. They're Allen screws. :-) Ed J. L. Trantham wrote: > They look like Torx Screws. Not so? > > Thanks, > > Joe > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of Rex > Sent: Monday, June 15, 2009 2:33 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] FE-5680A thermal management > > > Hal Murray wrote: > > >> Leigh at WA5ZNU.org said: >> >> >> >>> For reference, Ridge Equipment has a photo of one of this year's crop >>> of FE-5680A mounted to a large aluminum plate. >>> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330233071735 >>> http://i43.tinypic.com/126cpcp.jpg >>> >>> >>> >> Is that an aluminum plate or the top side of a PCB used as a heat sink? >> >> To me, the first picture looks green/FR4 around the edges. (and a >> stripe on >> the left) >> >> >> >> > Yes, that is a portion of the board I described in an earlier message. > The board is thick fiberglass plated heavily on both the top and bottom. > The board in the picture has been cut both above and below the 5680A. > The plating ended about where the lower cut is, but the plating > continued farther above the top of the unit in the picture. My earlier > message gave the dimensions. > > One minor note about this board. The screws holding the 5680 to the > borad were an unusual type. I can't remember, I think they may have been > a square drive. They were difficult to remove as I had no proper tool to > unscrew them. I think I made something from steel rod to start them > losening. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From gwinn at raytheon.com Mon Jun 15 16:30:31 2009 From: gwinn at raytheon.com (Joseph M Gwinn) Date: Mon, 15 Jun 2009 12:30:31 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <1231b6a80906150357g4b89deeewd4cad3e239d8e13a@mail.gmail.com> Message-ID: time-nuts-bounces at febo.com wrote on 06/15/2009 06:57:13 AM: > They suggest you add a small amount of chlorine bleach to water > containers you store for natural disaster emergencies. You also need > to replace the water on a regular basis even with the bleach in it. > Here in Christchurch, New Zealand, they don't even chlorinate the > water we drink, it comes straight out of a natural aquifer underneath > us. As for the long term effects of bleach on plastic bottles, one > would imagine that it would accelerate the breakdown of the plastic. > Interestingly, someone in the know, talking about land-fill sites, > suggested that there is essentially no breakdown of these items when > they are fully embeded in the fill. Luckily we recycle almost > everything here but it would make interesting finds for future > archaeologists. > > A glass vessel with a stabilised rubber stopper or lapped glass > stopper and wax sealed would seemingly be better for long term use and > the glass should conduct the heat better than plastic for our xtal > oven ballast. But glass is not a solid, it's a liquid after all and > would eventually find the lowest point with time. Mind you, that is a > very long time. The other thing that comes to mind is that > state-change salt type of liquid that absorbs energy well. Of course, > you could use an eskey if it was not holding the beer and may be a > less smelly alternative than a used fridge at room temp. I was the one who originally rained on the use-water-in-a-bottle approach. The response was that even a child could store water. Well, that is not the common experience with water-cooled equipment, which always manages to require continual maintenance attention, so I went quiet, and listened as the subject was explored. It has become apparent from the issues and increasingly complex schemes to solving tose issues that keeping water in its place is not exactly child's play, and it seems to me that water is far more trouble and even expense than simply getting a big hunk of scrap metal, unless one needs tons of thermal mass. If one needs fast thermal exchange with the air, drill some holes or use a set of thick plates with spacers, so the distance from air to the most remote part of the mass is no more than an inch or so. Or, use a big hunk of copper or aluminum. Or both. If one needs tons of thermal mass plus rapid exchange with the air, use brick checkerwork or a pebble bed, a standard industrial approach: < http://en.wikipedia.org/wiki/Regenerator>. For thermal stabilization of timekeeping equipment, a pebble bed and a circulating fan is cheap and easy. Joe Gwinn > 73, > Steve > > 2009/6/15 Didier Juges : > > Here in Florida, we routinely store water in prevision of the > next big one. > > > > Plastic water bottles (any brand) start looking funny > (shrunk) after a few > > months, and downright scary (as in: you don't want to drink > from THAT) after > > a year or so. > > > > It seems the gallon jugs do somewhat better than the smaller > bottles. I had > > jugs that still looked OK after a year, but not good after > two. The pastic > > seems much thicker, and maybe it slows down the process? > > > > It's been like that for as long as I have lived here, i.e. > since 1985. I do > > not know if it is related to the climate. It makes no > appreciable difference > > if the water is stored in the garage (no A/C) or in the house. > > > > Didier KO4BB > > > >> -----Original Message----- > >> From: time-nuts-bounces at febo.com > >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Thomas A. Frank > >> Sent: Saturday, June 13, 2009 12:16 PM > >> To: Discussion of precise time and frequency measurement > >> Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature > >> > >> More to the point, you will be disappointed to find the bottles will > >> NOT last that long. > >> > >> Cleaning out the cupboard recently, I can across some bottled water > >> that had 1998 date codes. Several had leaked, but one was still > >> intact enough to show the likely problem. It would appear that over > >> the past 10 years, the gases dissolved in the water migrated through > >> the plastic (or the cap seal), resulting in a vacuum forming in the > >> bottle. This distended the bottles and caused structural failure. > >> > >> Either that, or the water caused the plastic to shrink. > >> > >> Glass would probably fair better. > >> > >> Tom Frank, KA2CDK > >> > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > -- > Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW > A man with one clock knows what time it is; > A man with two clocks is never quite sure. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > and follow the instructions there. > > The following line is added for your protection and will be > used for analysis if this message is reported as spam: > > (Raytheon Analysis: IP=64.34.164.147; e-from=time-nuts- > bounces+gwinn=raytheon.com at febo.com; from=sar10538 at gmail.com; > date=Jun 15, 2009 10:59:08 AM; subject=Re: [time-nuts] > Thunderbolt stability and ambient temperature) From cfharris at erols.com Mon Jun 15 17:19:14 2009 From: cfharris at erols.com (Chuck Harris) Date: Mon, 15 Jun 2009 13:19:14 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A368292.8060607@erols.com> Joseph M Gwinn wrote: > > I was the one who originally rained on the use-water-in-a-bottle approach. > The response was that even a child could store water. Well, that is not > the common experience with water-cooled equipment, which always manages to > require continual maintenance attention, so I went quiet, and listened as > the subject was explored. But it isn't necessary to get this complicated. You don't need moving parts, and I agree, you don't want to be piping the stuff around. The increasingly complex schemes are coming about because posters are trying to invent reasons why this is hard work. They are ignoring the simple fact that small quantities of water can be easily stored for a whole lot of years. A couple of examples from my own life: I live on well water. If the electricity goes out, and it regularly does, I cannot pump the water to flush the toilets. That goes over really well with my wife. To avoid this problem I keep three 5 gallon plastic jugs of water in the basement. They sit there for very long periods of time, and are invariably full when I need them to force a manual flush. Simple! Don't like plastic water jugs? Ok, use a 5 gallon plastic paint pail. They are O-ring sealed, and will stay full of water for a decade or more without any attention. I have one in my basement that I used for cooling water when I was soldering the plumbing in my house... 5 years ago. It is open, with a lid just sitting on top. The pale is still full of water. Some evaporation has undoubtedly occurred, but not enough to matter. Things would be much better if I bothered to snap the lid down... actually things would be much better if I bothered to dump the water and cleaned out the pail... I think I might. For me, processing a junk automobile engine so that I would A) want it in my house, and B) would be able to use it as a ballast is ridiculous. The stupid things cost $50 to $100 in the junk yard, and are a really inconvenient shape. I'd much rather stack $50, or $100 worth of polyethylene chemical bottles full of water than mess with a junk engine. > > It has become apparent from the issues and increasingly complex schemes to > solving tose issues that keeping water in its place is not exactly child's > play, and it seems to me that water is far more trouble and even expense > than simply getting a big hunk of scrap metal, unless one needs tons of > thermal mass. If one needs fast thermal exchange with the air, drill some > holes or use a set of thick plates with spacers, so the distance from air > to the most remote part of the mass is no more than an inch or so. Or, > use a big hunk of copper or aluminum. Or both. Have you even looked at the price of copper lately? It is so high that even the rich cannot afford to use it for flashing, gutters or roofs anymore! And when you are all done, copper and aluminum cannot store the same amount of heat, pound-for-pound, as plain old dumb water. > > If one needs tons of thermal mass plus rapid exchange with the air, use > brick checkerwork or a pebble bed, a standard industrial approach: < That can be a good way too. How are you going to keep it dry and mold free? What about the ever present dust? -Chuck Harris From jfor at quik.com Mon Jun 15 17:28:01 2009 From: jfor at quik.com (J. Forster) Date: Mon, 15 Jun 2009 10:28:01 -0700 (PDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A368292.8060607@erols.com> References: <4A368292.8060607@erols.com> Message-ID: <1272.12.6.201.205.1245086881.squirrel@popacctsnew.quik.com> Hey Guys, For time and less effort you could likely cobble up a Hydrogen Maser and be done with it. :=)) -John ======= > Joseph M Gwinn wrote: >> >> I was the one who originally rained on the use-water-in-a-bottle >> approach. >> The response was that even a child could store water. Well, that is >> not >> the common experience with water-cooled equipment, which always manages >> to >> require continual maintenance attention, so I went quiet, and listened >> as >> the subject was explored. > > But it isn't necessary to get this complicated. You don't need moving > parts, > and I agree, you don't want to be piping the stuff around. > > The increasingly complex schemes are coming about because posters are > trying to invent reasons why this is hard work. They are ignoring the > simple fact that small quantities of water can be easily stored for a > whole > lot of years. > > A couple of examples from my own life: I live on well water. If the > electricity goes out, and it regularly does, I cannot pump the water to > flush the toilets. That goes over really well with my wife. To avoid > this problem I keep three 5 gallon plastic jugs of water in the basement. > They sit there for very long periods of time, and are invariably full when > I need them to force a manual flush. Simple! > > Don't like plastic water jugs? Ok, use a 5 gallon plastic paint pail. > They > are O-ring sealed, and will stay full of water for a decade or more > without > any attention. I have one in my basement that I used for cooling water > when > I was soldering the plumbing in my house... 5 years ago. It is open, with > a lid just sitting on top. The pale is still full of water. Some > evaporation > has undoubtedly occurred, but not enough to matter. Things would be much > better if I bothered to snap the lid down... actually things would be much > better if I bothered to dump the water and cleaned out the pail... I think > I might. > > For me, processing a junk automobile engine so that I would A) want it > in my house, and B) would be able to use it as a ballast is ridiculous. > The stupid things cost $50 to $100 in the junk yard, and are a really > inconvenient shape. I'd much rather stack $50, or $100 worth of > polyethylene > chemical bottles full of water than mess with a junk engine. > >> >> It has become apparent from the issues and increasingly complex schemes >> to >> solving tose issues that keeping water in its place is not exactly >> child's >> play, and it seems to me that water is far more trouble and even expense >> than simply getting a big hunk of scrap metal, unless one needs tons of >> thermal mass. If one needs fast thermal exchange with the air, drill >> some >> holes or use a set of thick plates with spacers, so the distance from >> air >> to the most remote part of the mass is no more than an inch or so. Or, >> use a big hunk of copper or aluminum. Or both. > > Have you even looked at the price of copper lately? It is so high that > even the rich cannot afford to use it for flashing, gutters or roofs > anymore! And when you are all done, copper and aluminum cannot store the > same amount of heat, pound-for-pound, as plain old dumb water. >> >> If one needs tons of thermal mass plus rapid exchange with the air, use >> brick checkerwork or a pebble bed, a standard industrial approach: < > > That can be a good way too. How are you going to keep it dry and mold > free? > > What about the ever present dust? > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From djl at montana.com Mon Jun 15 18:13:07 2009 From: djl at montana.com (Don Latham) Date: Mon, 15 Jun 2009 12:13:07 -0600 (MDT) Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A368292.8060607@erols.com> References: <4A368292.8060607@erols.com> Message-ID: Could we please get off the water kick? Every time I read one of these posts I have to pee. D > Joseph M Gwinn wrote: >> >> I was the one who originally rained on the use-water-in-a-bottle >> approach. >> The response was that even a child could store water. Well, that is >> not >> the common experience with water-cooled equipment, which always manages >> to >> require continual maintenance attention, so I went quiet, and listened >> as >> the subject was explored. > > But it isn't necessary to get this complicated. You don't need moving > parts, > and I agree, you don't want to be piping the stuff around. > > The increasingly complex schemes are coming about because posters are > trying to invent reasons why this is hard work. They are ignoring the > simple fact that small quantities of water can be easily stored for a > whole > lot of years. > > A couple of examples from my own life: I live on well water. If the > electricity goes out, and it regularly does, I cannot pump the water to > flush the toilets. That goes over really well with my wife. To avoid > this problem I keep three 5 gallon plastic jugs of water in the basement. > They sit there for very long periods of time, and are invariably full when > I need them to force a manual flush. Simple! > > Don't like plastic water jugs? Ok, use a 5 gallon plastic paint pail. > They > are O-ring sealed, and will stay full of water for a decade or more > without > any attention. I have one in my basement that I used for cooling water > when > I was soldering the plumbing in my house... 5 years ago. It is open, with > a lid just sitting on top. The pale is still full of water. Some > evaporation > has undoubtedly occurred, but not enough to matter. Things would be much > better if I bothered to snap the lid down... actually things would be much > better if I bothered to dump the water and cleaned out the pail... I think > I might. > > For me, processing a junk automobile engine so that I would A) want it > in my house, and B) would be able to use it as a ballast is ridiculous. > The stupid things cost $50 to $100 in the junk yard, and are a really > inconvenient shape. I'd much rather stack $50, or $100 worth of > polyethylene > chemical bottles full of water than mess with a junk engine. > >> >> It has become apparent from the issues and increasingly complex schemes >> to >> solving tose issues that keeping water in its place is not exactly >> child's >> play, and it seems to me that water is far more trouble and even expense >> than simply getting a big hunk of scrap metal, unless one needs tons of >> thermal mass. If one needs fast thermal exchange with the air, drill >> some >> holes or use a set of thick plates with spacers, so the distance from >> air >> to the most remote part of the mass is no more than an inch or so. Or, >> use a big hunk of copper or aluminum. Or both. > > Have you even looked at the price of copper lately? It is so high that > even the rich cannot afford to use it for flashing, gutters or roofs > anymore! And when you are all done, copper and aluminum cannot store the > same amount of heat, pound-for-pound, as plain old dumb water. >> >> If one needs tons of thermal mass plus rapid exchange with the air, use >> brick checkerwork or a pebble bed, a standard industrial approach: < > > That can be a good way too. How are you going to keep it dry and mold > free? > > What about the ever present dust? > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com From hmurray at megapathdsl.net Mon Jun 15 19:23:40 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Mon, 15 Jun 2009 12:23:40 -0700 Subject: [time-nuts] Lifetime of glass containers Message-ID: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> dave at uk-ar.co.uk said: > Or as someone else suggested, use a Glass container. So long as you > don't want it to last for many 100's of years, as Glass is not a > solid, it is a "super cooled fluid" and as such it flows like Ice over > time, just that it takes much much longer to do so! As best as I can tell, the glass-is-a-liquid story is bunk. http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass I was going to ask if anybody had tried to measure it. That seems like something a time-nut would know about. The astronomers have been running tests for years. Their mirrors don't seem to sag enough to notice, and they are very good at noticing tiny distortions. -- These are my opinions, not necessarily my employer's. I hate spam. From rexa at sonic.net Mon Jun 15 19:41:46 2009 From: rexa at sonic.net (Rex) Date: Mon, 15 Jun 2009 12:41:46 -0700 Subject: [time-nuts] FE-5680A thermal management In-Reply-To: <4A3668A3.50206@sasktel.net> References: <523D7924D3114D1F9CB8F42F9C94955B@S0028384766> <4A3668A3.50206@sasktel.net> Message-ID: <4A36A3FA.8070907@sonic.net> Nevermind. I went back and looked again. The screws are a bit odd and sloppy tolerences, but a 1/16 inch allen wrench seems to work. I guess my memory from a couple years back was a bit off. -Rex Ed Palmer wrote: > No. I have one and it's very appropriate for a piece of Time-Nut > equipment. They're Allen screws. :-) > > Ed > > J. L. Trantham wrote: > >> They look like Torx Screws. Not so? >> >> Thanks, >> >> Joe >> >> -----Original Message----- >> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On >> Behalf Of Rex >> Sent: Monday, June 15, 2009 2:33 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] FE-5680A thermal management >> >> >> Hal Murray wrote: >> >> >> >>> Leigh at WA5ZNU.org said: >>> >>> >>> >>> >>>> For reference, Ridge Equipment has a photo of one of this year's >>>> crop of FE-5680A mounted to a large aluminum plate. >>>> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330233071735 >>>> http://i43.tinypic.com/126cpcp.jpg >>>> >>>> >>> >>> Is that an aluminum plate or the top side of a PCB used as a heat sink? >>> >>> To me, the first picture looks green/FR4 around the edges. (and a >>> stripe on >>> the left) >>> >>> >>> >>> >> >> Yes, that is a portion of the board I described in an earlier >> message. The board is thick fiberglass plated heavily on both the top >> and bottom. The board in the picture has been cut both above and >> below the 5680A. The plating ended about where the lower cut is, but >> the plating continued farther above the top of the unit in the >> picture. My earlier message gave the dimensions. >> >> One minor note about this board. The screws holding the 5680 to the >> borad were an unusual type. I can't remember, I think they may have >> been a square drive. They were difficult to remove as I had no proper >> tool to unscrew them. I think I made something from steel rod to >> start them losening. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From dgcarlson at sbcglobal.net Mon Jun 15 19:56:42 2009 From: dgcarlson at sbcglobal.net (Dave Carlson) Date: Mon, 15 Jun 2009 12:56:42 -0700 Subject: [time-nuts] Lifetime of glass containers References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Not to charge in, but I've looked at ordinary window pane glass in very old buildings and you can actually see the rippling effect that occurred over time, showing the "flow" of the glass toward the lower edge of the pane. One presumes that the panes were relatively uniform when installed 120 years earlier. Sounds liquid to me. Dave ----- Original Message ----- From: "Hal Murray" To: Sent: Monday, June 15, 2009 12:23 Subject: [time-nuts] Lifetime of glass containers dave at uk-ar.co.uk said: > Or as someone else suggested, use a Glass container. So long as you > don't want it to last for many 100's of years, as Glass is not a > solid, it is a "super cooled fluid" and as such it flows like Ice over > time, just that it takes much much longer to do so! As best as I can tell, the glass-is-a-liquid story is bunk. http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass I was going to ask if anybody had tried to measure it. That seems like something a time-nut would know about. The astronomers have been running tests for years. Their mirrors don't seem to sag enough to notice, and they are very good at noticing tiny distortions. -- These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From gwinn at raytheon.com Mon Jun 15 20:07:48 2009 From: gwinn at raytheon.com (Joseph M Gwinn) Date: Mon, 15 Jun 2009 16:07:48 -0400 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: time-nuts-bounces at febo.com wrote on 06/15/2009 03:56:42 PM: > Not to charge in, but I've looked at ordinary window pane glass in very old > buildings and you can actually see the rippling effect that occurred over > time, showing the "flow" of the glass toward the lower edge of the pane. One > presumes that the panes were relatively uniform when installed 120 years > earlier. Sounds liquid to me. It's hard to say because the panes were not flat to begin with. Window glass was then made by manually blowing a big cylinder and then cutting the hot glass and unrolling the cylinder onto a flat charcoal surface. The ripples are largely parallel to the axis of that original cylinder. Modern window glass is made by pouring a sheet of molten glass out onto molten tin, where the glass floats and flattens itself. The glass sheet is pushed steadily away from the glass pot, cooling as it goes until hard enough to cut into sheets. Joe Gwinn > Dave > > ----- Original Message ----- > From: "Hal Murray" > To: > Sent: Monday, June 15, 2009 12:23 > Subject: [time-nuts] Lifetime of glass containers > > > > dave at uk-ar.co.uk said: > > Or as someone else suggested, use a Glass container. So long as you > > don't want it to last for many 100's of years, as Glass is not a > > solid, it is a "super cooled fluid" and as such it flows like Ice over > > time, just that it takes much much longer to do so! > > As best as I can tell, the glass-is-a-liquid story is bunk. > http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass > > I was going to ask if anybody had tried to measure it. That seems like > something a time-nut would know about. > > The astronomers have been running tests for years. Their > mirrors don't seem > to sag enough to notice, and they are very good at noticing tiny > distortions. > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > and follow the instructions there. > > The following line is added for your protection and will be > used for analysis if this message is reported as spam: > > (Raytheon Analysis: IP=64.34.164.147; e-from=time-nuts- > bounces+gwinn=raytheon.com at febo.com; from=dgcarlson at sbcglobal. > net; date=Jun 15, 2009 7:57:28 PM; subject=Re: [time-nuts] > Lifetime of glass containers) From cfharris at erols.com Mon Jun 15 20:17:18 2009 From: cfharris at erols.com (Chuck Harris) Date: Mon, 15 Jun 2009 16:17:18 -0400 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: <4A36AC4E.8090203@erols.com> That's just it, the glass wasn't flat to begin with. Early glass was poured out into sheets, and was quite non uniform in thickness. -Chuck Harris Dave Carlson wrote: > Not to charge in, but I've looked at ordinary window pane glass in very old > buildings and you can actually see the rippling effect that occurred over > time, showing the "flow" of the glass toward the lower edge of the pane. One > presumes that the panes were relatively uniform when installed 120 years > earlier. Sounds liquid to me. > > Dave From jmfranke at cox.net Mon Jun 15 20:30:06 2009 From: jmfranke at cox.net (jmfranke) Date: Mon, 15 Jun 2009 16:30:06 -0400 Subject: [time-nuts] Lifetime of glass containers References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net><88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <4A36AC4E.8090203@erols.com> Message-ID: Also, people have noted that old glass window panes from the colonial era are thicker at the base than the top. This was due to the glacier selecting the orientation of each piece. Otherwise the prism effect would break up horizontal lines viewed through the panes. We did the same with segmented precision glass windows used in wind tunnels at NASA. Ancient glass bottles with chips or broken sections still have sharp edges. John WA4WDL -------------------------------------------------- From: "Chuck Harris" Sent: Monday, June 15, 2009 4:17 PM To: "Dave Carlson" ; "Discussion of precise time and frequency measurement" Subject: Re: [time-nuts] Lifetime of glass containers > That's just it, the glass wasn't flat to begin with. > Early glass was poured out into sheets, and was quite > non uniform in thickness. > > -Chuck Harris > > Dave Carlson wrote: >> Not to charge in, but I've looked at ordinary window pane glass in very >> old buildings and you can actually see the rippling effect that occurred >> over time, showing the "flow" of the glass toward the lower edge of the >> pane. One presumes that the panes were relatively uniform when installed >> 120 years earlier. Sounds liquid to me. >> >> Dave > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From james.p.lux at jpl.nasa.gov Mon Jun 15 20:45:21 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Mon, 15 Jun 2009 13:45:21 -0700 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Dave Carlson > Sent: Monday, June 15, 2009 12:57 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Lifetime of glass containers > > Not to charge in, but I've looked at ordinary window pane > glass in very old buildings and you can actually see the > rippling effect that occurred over time, showing the "flow" > of the glass toward the lower edge of the pane. One presumes > that the panes were relatively uniform when installed 120 > years earlier. Sounds liquid to me. > Nope.. 120 years ago, I don't think they had modern float glass or even continuous casting processes. You blew a large cylinder, cut it open, and laid it flat in an oven, or took molten glass, poured it onto a flat surface, rolled it flat, then polished it (with a "plate" hence the name "plate glass") Sometime early in the 1900's they started making glass in a sort of continuous casting process with slots or rollers or some such scheme to make sheets, but it wasn't very flat in an optical sense. After WW II, they developed the float glass process, where the molten glass is floated across liquid metal, giving you continuous production AND flat surfaces. So, what you're seeing in old buildings is the fact that flat glass was really hard to make and expensive. You might use it in a mirror, for instance, if you didn't use polished metal instead. I'm sure wikipedia has more than anyone would want to know about sheet glass manufacture.. From m0ycm at veenstras.com Mon Jun 15 20:54:40 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Mon, 15 Jun 2009 21:54:40 +0100 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: <14DA1786743B4F09BCB0B7808D6492C8@hp> Before you charge in, read http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass From jfor at quik.com Mon Jun 15 21:26:18 2009 From: jfor at quik.com (J. Forster) Date: Mon, 15 Jun 2009 14:26:18 -0700 (PDT) Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: <1087.12.6.201.112.1245101178.squirrel@popacctsnew.quik.com> That COULD be an illusion. Old glass was not very uniform and I've been told the artisans always installed it thick end down. FWIW, -John ============= > Not to charge in, but I've looked at ordinary window pane glass in very > old > buildings and you can actually see the rippling effect that occurred over > time, showing the "flow" of the glass toward the lower edge of the pane. > One > presumes that the panes were relatively uniform when installed 120 years > earlier. Sounds liquid to me. > > Dave > > ----- Original Message ----- > From: "Hal Murray" > To: > Sent: Monday, June 15, 2009 12:23 > Subject: [time-nuts] Lifetime of glass containers > > > > dave at uk-ar.co.uk said: >> Or as someone else suggested, use a Glass container. So long as you >> don't want it to last for many 100's of years, as Glass is not a >> solid, it is a "super cooled fluid" and as such it flows like Ice over >> time, just that it takes much much longer to do so! > > As best as I can tell, the glass-is-a-liquid story is bunk. > http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass > > I was going to ask if anybody had tried to measure it. That seems like > something a time-nut would know about. > > The astronomers have been running tests for years. Their mirrors don't > seem > to sag enough to notice, and they are very good at noticing tiny > distortions. > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From jfor at quik.com Mon Jun 15 21:34:21 2009 From: jfor at quik.com (J. Forster) Date: Mon, 15 Jun 2009 14:34:21 -0700 (PDT) Subject: [time-nuts] Lifetime of glass containers In-Reply-To: References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> Interestingly, I recently had dinner with an archeology professor, interested in the Etruscan period. She had just discovered a flatish piece of glass i9n a dig, thousands of years old, and believes it was made essentially like rolling out dough on a slab while red hot. -John ============= >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Dave Carlson >> Sent: Monday, June 15, 2009 12:57 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Lifetime of glass containers >> >> Not to charge in, but I've looked at ordinary window pane >> glass in very old buildings and you can actually see the >> rippling effect that occurred over time, showing the "flow" >> of the glass toward the lower edge of the pane. One presumes >> that the panes were relatively uniform when installed 120 >> years earlier. Sounds liquid to me. >> > Nope.. 120 years ago, I don't think they had modern float glass or even > continuous casting processes. > > You blew a large cylinder, cut it open, and laid it flat in an oven, or > took molten glass, poured it onto a flat surface, rolled it flat, then > polished it (with a "plate" hence the name "plate glass") > > Sometime early in the 1900's they started making glass in a sort of > continuous casting process with slots or rollers or some such scheme to > make sheets, but it wasn't very flat in an optical sense. > > After WW II, they developed the float glass process, where the molten > glass is floated across liquid metal, giving you continuous production AND > flat surfaces. > > So, what you're seeing in old buildings is the fact that flat glass was > really hard to make and expensive. You might use it in a mirror, for > instance, if you didn't use polished metal instead. > > I'm sure wikipedia has more than anyone would want to know about sheet > glass manufacture.. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From james.p.lux at jpl.nasa.gov Mon Jun 15 21:49:35 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Mon, 15 Jun 2009 14:49:35 -0700 Subject: [time-nuts] Pre-industrial timekeeping accuracy RE: Lifetime of glass containers In-Reply-To: <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of J. Forster > Sent: Monday, June 15, 2009 2:34 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Lifetime of glass containers > > Interestingly, I recently had dinner with an archeology > professor, interested in the Etruscan period. She had just > discovered a flatish piece of glass i9n a dig, thousands of > years old, and believes it was made essentially like rolling > out dough on a slab while red hot. > > -John > Returning to a more time-nuts-y topic.. What sort of time measurement accuracy would folks 2000 years ago have had? For instance, were they aware of the (relative) constancy of the swings of a pendulum of constant length? I remember stories from school about Galileo using his pulse as a clock. They're probably apocryphal, and I would think that he would have easy access to other things that tick once a second or there abouts (dripping water, etc, if not swings of a pendulum). I'm also familiar with the famous Shakespearean anachronism of the striking clock in "Julius Caesar", and the usual commentary says the Romans had only sundials and clepsydra. So how good is a clepsydra? What if we go back a 1000 years? From jfor at quik.com Mon Jun 15 22:04:25 2009 From: jfor at quik.com (J. Forster) Date: Mon, 15 Jun 2009 15:04:25 -0700 (PDT) Subject: [time-nuts] Pre-industrial timekeeping accuracy RE: Lifetime of glass containers In-Reply-To: References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> Message-ID: <1165.12.6.201.112.1245103465.squirrel@popacctsnew.quik.com> I'm no expert on ancient timekeeping, but nothing we'd call precision. Some possibles are: Water clocks Sand hour glasses Sun dials Time candles I think Christian Heugens (? sp) invented the pendulum for timekeeping. Your question is really more of a history of science. I just happen know a field archeologist FWIW, -John ========== > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of J. Forster >> Sent: Monday, June 15, 2009 2:34 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Lifetime of glass containers >> >> Interestingly, I recently had dinner with an archeology >> professor, interested in the Etruscan period. She had just >> discovered a flatish piece of glass i9n a dig, thousands of >> years old, and believes it was made essentially like rolling >> out dough on a slab while red hot. >> >> -John >> > > Returning to a more time-nuts-y topic.. > > What sort of time measurement accuracy would folks 2000 years ago have > had? > > For instance, were they aware of the (relative) constancy of the swings of > a pendulum of constant length? > > I remember stories from school about Galileo using his pulse as a clock. > They're probably apocryphal, and I would think that he would have easy > access to other things that tick once a second or there abouts (dripping > water, etc, if not swings of a pendulum). > > I'm also familiar with the famous Shakespearean anachronism of the > striking clock in "Julius Caesar", and the usual commentary says the > Romans had only sundials and clepsydra. So how good is a clepsydra? What > if we go back a 1000 years? > > From namichie at gmail.com Mon Jun 15 22:08:58 2009 From: namichie at gmail.com (Neville Michie) Date: Tue, 16 Jun 2009 08:08:58 +1000 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <35DF68EA-9D09-4CB1-995A-318F4E448FA1@gmail.com> hi, the main point of the water approach was the high performance of water as a heat storage medium. Quartz, if one can assume that is what pebbles are made of, has a density of 2.7 g/cc but a specific heat of only 0.2 cal/gm C. That is only 0.54 cal/cc C compared to water with a figure of 1.0. So water still has greater merit as a thermal buffer. Cheers, Neville Michie On 16/06/2009, at 2:30 AM, Joseph M Gwinn wrote: > time-nuts-bounces at febo.com wrote on 06/15/2009 06:57:13 AM: > >> They suggest you add a small amount of chlorine bleach to water >> containers you store for natural disaster emergencies. You also need >> to replace the water on a regular basis even with the bleach in it. >> Here in Christchurch, New Zealand, they don't even chlorinate the >> water we drink, it comes straight out of a natural aquifer underneath >> us. As for the long term effects of bleach on plastic bottles, one >> would imagine that it would accelerate the breakdown of the plastic. >> Interestingly, someone in the know, talking about land-fill sites, >> suggested that there is essentially no breakdown of these items when >> they are fully embeded in the fill. Luckily we recycle almost >> everything here but it would make interesting finds for future >> archaeologists. >> >> A glass vessel with a stabilised rubber stopper or lapped glass >> stopper and wax sealed would seemingly be better for long term use >> and >> the glass should conduct the heat better than plastic for our xtal >> oven ballast. But glass is not a solid, it's a liquid after all and >> would eventually find the lowest point with time. Mind you, that is a >> very long time. The other thing that comes to mind is that >> state-change salt type of liquid that absorbs energy well. Of course, >> you could use an eskey if it was not holding the beer and may be a >> less smelly alternative than a used fridge at room temp. > > I was the one who originally rained on the use-water-in-a-bottle > approach. > The response was that even a child could store water. Well, that > is not > the common experience with water-cooled equipment, which always > manages to > require continual maintenance attention, so I went quiet, and > listened as > the subject was explored. > > It has become apparent from the issues and increasingly complex > schemes to > solving tose issues that keeping water in its place is not exactly > child's > play, and it seems to me that water is far more trouble and even > expense > than simply getting a big hunk of scrap metal, unless one needs > tons of > thermal mass. If one needs fast thermal exchange with the air, > drill some > holes or use a set of thick plates with spacers, so the distance > from air > to the most remote part of the mass is no more than an inch or so. > Or, > use a big hunk of copper or aluminum. Or both. > > If one needs tons of thermal mass plus rapid exchange with the air, > use > brick checkerwork or a pebble bed, a standard industrial approach: < > http://en.wikipedia.org/wiki/Regenerator>. For thermal > stabilization of > timekeeping equipment, a pebble bed and a circulating fan is cheap and > easy. > > Joe Gwinn > > >> 73, >> Steve >> >> 2009/6/15 Didier Juges : >>> Here in Florida, we routinely store water in prevision of the >> next big one. >>> >>> Plastic water bottles (any brand) start looking funny >> (shrunk) after a few >>> months, and downright scary (as in: you don't want to drink >> from THAT) after >>> a year or so. >>> >>> It seems the gallon jugs do somewhat better than the smaller >> bottles. I had >>> jugs that still looked OK after a year, but not good after >> two. The pastic >>> seems much thicker, and maybe it slows down the process? >>> >>> It's been like that for as long as I have lived here, i.e. >> since 1985. I do >>> not know if it is related to the climate. It makes no >> appreciable difference >>> if the water is stored in the garage (no A/C) or in the house. >>> >>> Didier KO4BB >>> >>>> -----Original Message----- >>>> From: time-nuts-bounces at febo.com >>>> [mailto:time-nuts-bounces at febo.com] On Behalf Of Thomas A. Frank >>>> Sent: Saturday, June 13, 2009 12:16 PM >>>> To: Discussion of precise time and frequency measurement >>>> Subject: Re: [time-nuts] Thunderbolt stability and ambient > temperature >>>> >>>> More to the point, you will be disappointed to find the bottles >>>> will >>>> NOT last that long. >>>> >>>> Cleaning out the cupboard recently, I can across some bottled water >>>> that had 1998 date codes. Several had leaked, but one was still >>>> intact enough to show the likely problem. It would appear that >>>> over >>>> the past 10 years, the gases dissolved in the water migrated >>>> through >>>> the plastic (or the cap seal), resulting in a vacuum forming in the >>>> bottle. This distended the bottles and caused structural failure. >>>> >>>> Either that, or the water caused the plastic to shrink. >>>> >>>> Glass would probably fair better. >>>> >>>> Tom Frank, KA2CDK >>>> >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to https://www.febo.com/cgi- >> bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> >> -- >> Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW >> A man with one clock knows what time it is; >> A man with two clocks is never quite sure. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to https://www.febo.com/cgi- >> bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> The following line is added for your protection and will be >> used for analysis if this message is reported as spam: >> >> (Raytheon Analysis: IP=64.34.164.147; e-from=time-nuts- >> bounces+gwinn=raytheon.com at febo.com; from=sar10538 at gmail.com; >> date=Jun 15, 2009 10:59:08 AM; subject=Re: [time-nuts] >> Thunderbolt stability and ambient temperature) > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. From t_list_1_only at braw.co.uk Mon Jun 15 22:49:16 2009 From: t_list_1_only at braw.co.uk (David ) Date: Mon, 15 Jun 2009 23:49:16 +0100 Subject: [time-nuts] Pre-industrial timekeeping accuracy RE: Lifetime of glass containers In-Reply-To: Message-ID: <42AAA6F6D4E54A8EBFD6C8C037D7870F@sun02h26m> I'm getting slightly suspicious about the assumptions as to what was available 2000 years ago, the remarkable Antikythera Mechanism points to some technologies of 2000 years ago being almost up to medieval European standards. Clearly Antikythera indicates there were a few stunning items around, the fact that there is virtually no trace remaining of anything else indicates the technology was very rare in its own time but its hard to imagine a mechanisim like this being invented from nowhere to solely to make one item and not pointing to small numbers of other intricate instruments being made. The people who made the Antikythera Mechanism would surely have been motivated to attempt timekeeping, Antikythera shows a competent technology had been developed, we are very lucky to have any evidence after 2 millenia of such a rare device. Links: http://news.bbc.co.uk/1/hi/sci/tech/6191462.stm http://www.math.sunysb.edu/~tony/whatsnew/column/antikytheraI-0400/kyth1.htm l http://www.math.sunysb.edu/~tony/whatsnew/column/antikytheraII-0500/diff1.ht ml > Returning to a more time-nuts-y topic.. > > What sort of time measurement accuracy would folks 2000 years > ago have had? > > For instance, were they aware of the (relative) constancy of > the swings of a pendulum of constant length? > > I remember stories from school about Galileo using his pulse > as a clock. They're probably apocryphal, and I would think > that he would have easy access to other things that tick once > a second or there abouts (dripping water, etc, if not swings > of a pendulum). > > I'm also familiar with the famous Shakespearean anachronism > of the striking clock in "Julius Caesar", and the usual > commentary says the Romans had only sundials and clepsydra. > So how good is a clepsydra? What if we go back a 1000 years? > > From namichie at gmail.com Mon Jun 15 22:54:31 2009 From: namichie at gmail.com (Neville Michie) Date: Tue, 16 Jun 2009 08:54:31 +1000 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: Hi, I used to work with a scientific glass blower who told me that the glass is a liquid story is bunk. He demonstrated by making a "hot spot" on the side of a piece of glass pipe. As it cooled it set a a very intense strain into the piece of glass. Between crossed polaroids it was very visible. He explained that it was beyond the strength of the glass and that it would break. The only question was when. One second, one hour, one week, one year.......... Four years later it fell out, although the force was enormous and the distance to move was submicroscopic there was no decrease of the force. He also showed with the crossed polaroids, that decade old glass ware still had all its strains. Glass may be a supercooled liquid in structure, but it is also a solid, more stable that most metals. cheers, Neville Michie On 16/06/2009, at 5:23 AM, Hal Murray wrote: > > dave at uk-ar.co.uk said: >> Or as someone else suggested, use a Glass container. So long as you >> don't want it to last for many 100's of years, as Glass is not a >> solid, it is a "super cooled fluid" and as such it flows like Ice >> over >> time, just that it takes much much longer to do so! > > As best as I can tell, the glass-is-a-liquid story is bunk. > http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass > > I was going to ask if anybody had tried to measure it. That seems > like something a time-nut would know about. > > The astronomers have been running tests for years. Their mirrors > don't seem to sag enough to notice, and they are very good at > noticing tiny distortions. > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. From gwinn at raytheon.com Mon Jun 15 23:01:58 2009 From: gwinn at raytheon.com (Joseph M Gwinn) Date: Mon, 15 Jun 2009 19:01:58 -0400 Subject: [time-nuts] Pre-industrial timekeeping accuracy RE: Lifetime of glass containers In-Reply-To: Message-ID: time-nuts-bounces at febo.com wrote on 06/15/2009 05:49:35 PM: > > > -----Original Message----- > > From: time-nuts-bounces at febo.com > > [mailto:time-nuts-bounces at febo.com] On Behalf Of J. Forster > > Sent: Monday, June 15, 2009 2:34 PM > > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] Lifetime of glass containers > > > > Interestingly, I recently had dinner with an archeology > > professor, interested in the Etruscan period. She had just > > discovered a flatish piece of glass i9n a dig, thousands of > > years old, and believes it was made essentially like rolling > > out dough on a slab while red hot. > > > > -John > > > > Returning to a more time-nuts-y topic.. > > What sort of time measurement accuracy would folks 2000 years > ago have had? > > For instance, were they aware of the (relative) constancy of > the swings of a pendulum of constant length? > > I remember stories from school about Galileo using his pulse as > a clock. They're probably apocryphal, and I would think that he > would have easy access to other things that tick once a second > or there abouts (dripping water, etc, if not swings of a pendulum). > > I'm also familiar with the famous Shakespearean anachronism of > the striking clock in "Julius Caesar", and the usual commentary > says the Romans had only sundials and clepsydra. So how good > is a clepsydra? What if we go back a 1000 years? Allan collected this in HP AN-1289: Joe Gwinn From max at maxsmusicplace.com Mon Jun 15 23:59:53 2009 From: max at maxsmusicplace.com (Max Robinson) Date: Mon, 15 Jun 2009 18:59:53 -0500 Subject: [time-nuts] Lifetime of glass containers References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net><88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> Message-ID: I know that one way they used to make window glass was to blow a big glass bubble and then roll it flat. Pressure prevented flattening of the last little bubble. I have seen examples of this kind of glass at Saint Augustine FL. Regards. Max. K 4 O D S. Email: max at maxsmusicplace.com Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Music site: http://www.maxsmusicplace.com To subscribe to the fun with tubes group send an email to, funwithtubes-subscribe at yahoogroups.com ----- Original Message ----- From: "J. Forster" To: "Discussion of precise time and frequency measurement" Sent: Monday, June 15, 2009 4:34 PM Subject: Re: [time-nuts] Lifetime of glass containers > Interestingly, I recently had dinner with an archeology professor, > interested in the Etruscan period. She had just discovered a flatish piece > of glass i9n a dig, thousands of years old, and believes it was made > essentially like rolling out dough on a slab while red hot. > > -John > > ============= > > >>> -----Original Message----- >>> From: time-nuts-bounces at febo.com >>> [mailto:time-nuts-bounces at febo.com] On Behalf Of Dave Carlson >>> Sent: Monday, June 15, 2009 12:57 PM >>> To: Discussion of precise time and frequency measurement >>> Subject: Re: [time-nuts] Lifetime of glass containers >>> >>> Not to charge in, but I've looked at ordinary window pane >>> glass in very old buildings and you can actually see the >>> rippling effect that occurred over time, showing the "flow" >>> of the glass toward the lower edge of the pane. One presumes >>> that the panes were relatively uniform when installed 120 >>> years earlier. Sounds liquid to me. >>> >> Nope.. 120 years ago, I don't think they had modern float glass or even >> continuous casting processes. >> >> You blew a large cylinder, cut it open, and laid it flat in an oven, or >> took molten glass, poured it onto a flat surface, rolled it flat, then >> polished it (with a "plate" hence the name "plate glass") >> >> Sometime early in the 1900's they started making glass in a sort of >> continuous casting process with slots or rollers or some such scheme to >> make sheets, but it wasn't very flat in an optical sense. >> >> After WW II, they developed the float glass process, where the molten >> glass is floated across liquid metal, giving you continuous production >> AND >> flat surfaces. >> >> So, what you're seeing in old buildings is the fact that flat glass was >> really hard to make and expensive. You might use it in a mirror, for >> instance, if you didn't use polished metal instead. >> >> I'm sure wikipedia has more than anyone would want to know about sheet >> glass manufacture.. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From djl at montana.com Tue Jun 16 00:54:41 2009 From: djl at montana.com (Don Latham) Date: Mon, 15 Jun 2009 18:54:41 -0600 (MDT) Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> Message-ID: <3071f08b28713ae8a39be8f61be5fc90.squirrel@webmail.montana.com> NO NO NO the ripples are due to the manufacturing process of the time Don Dave Carlson > Not to charge in, but I've looked at ordinary window pane glass in very > old > buildings and you can actually see the rippling effect that occurred over > time, showing the "flow" of the glass toward the lower edge of the pane. > One > presumes that the panes were relatively uniform when installed 120 years > earlier. Sounds liquid to me. > > Dave > > ----- Original Message ----- > From: "Hal Murray" > To: > Sent: Monday, June 15, 2009 12:23 > Subject: [time-nuts] Lifetime of glass containers > > > > dave at uk-ar.co.uk said: >> Or as someone else suggested, use a Glass container. So long as you >> don't want it to last for many 100's of years, as Glass is not a >> solid, it is a "super cooled fluid" and as such it flows like Ice over >> time, just that it takes much much longer to do so! > > As best as I can tell, the glass-is-a-liquid story is bunk. > http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass > > I was going to ask if anybody had tried to measure it. That seems like > something a time-nut would know about. > > The astronomers have been running tests for years. Their mirrors don't > seem > to sag enough to notice, and they are very good at noticing tiny > distortions. > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com From david.bengtson at gmail.com Tue Jun 16 02:20:08 2009 From: david.bengtson at gmail.com (David Bengtson) Date: Mon, 15 Jun 2009 22:20:08 -0400 Subject: [time-nuts] test mailing from a new member In-Reply-To: <4A361306.70302@rubidium.dyndns.org> References: <4A361306.70302@rubidium.dyndns.org> Message-ID: Well, there's what I would like it to say, and then there is reality... I'm an RF engineer by profession, and I've been lurking on this list for a while, soaking up knowledge. I picked up one of the Thunderbolts from TAPR, and have had that running, hooked up to Lady Heather, so I've played a bit with that box, watching it get lock, and reduce the error over time. I've just I've recently gotten an opportunity to work on a GPSDO at work, and so I now have a real need to pick up some more information on the design tradeoffs and approaches in a GPSDO. I've plowed through a pile of old emails, but it's difficult to get a good overview from email threads. I would appreciate links to discussions on the tradeoffs inherent in a GPSDO. Sampling clock rate, filter bandwidths, jitter requirements etc. Thanks Dave On Mon, Jun 15, 2009 at 5:23 AM, Magnus Danielson wrote: > Hej David! > > David Bengtson skrev: >> >> If this had been a real message, there would have been content here. > > Assuming there had been a real message there, like a presentation of you, > what would it say? > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From service at frequencystandards.com Tue Jun 16 02:47:04 2009 From: service at frequencystandards.com (service at frequencystandards.com) Date: Mon, 15 Jun 2009 21:47:04 -0500 (CDT) Subject: [time-nuts] manual request. Message-ID: <1693.75.163.170.128.1245120424.squirrel@www.frequencystandards.com> I have had a request for a manual for BALL Efratom Division Portable Clock Model PC-10. I will put you in direct contact with them if you have one. They are willing to pay for a copy of it. Thanks, Chuck Norton From jfor at quik.com Tue Jun 16 02:51:40 2009 From: jfor at quik.com (J. Forster) Date: Mon, 15 Jun 2009 19:51:40 -0700 (PDT) Subject: [time-nuts] manual request. In-Reply-To: <1693.75.163.170.128.1245120424.squirrel@www.frequencystandards.com> References: <1693.75.163.170.128.1245120424.squirrel@www.frequencystandards.com> Message-ID: <1635.12.6.201.33.1245120700.squirrel@popacctsnew.quik.com> Sorry, no got. -John ============= > I have had a request for a manual for BALL Efratom Division Portable Clock > Model PC-10. I will put you in direct contact with them if you have one. > They are willing to pay for a copy of it. > Thanks, Chuck Norton > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From Leigh at WA5ZNU.org Tue Jun 16 03:12:46 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr WA5ZNU) Date: Mon, 15 Jun 2009 20:12:46 -0700 Subject: [time-nuts] Thunderbolts, time references, NTP etc. In-Reply-To: References: Message-ID: <4A370DAE.4050605@WA5ZNU.org> It's "fluke.l" not "flukel" who I've dealt with quite recently, and many other more venerable folks on this list have commented on as well. Leigh. > Is this good value, and a trusted seller? > > I went looking for "Fluke1" as listed earlier on here for these devices > (Thunderbolt GPS disciplined referenced sources) but though I > (eventually) found the user, no activity was shown for some time. So, I > went looking for the product instead, and found (among other things) > this item 170344432395 (you know where to look.) > ... > Dave B. > G0WBX. > > ___ From ralph at ralphsmith.org Tue Jun 16 03:13:10 2009 From: ralph at ralphsmith.org (Ralph Smith) Date: Mon, 15 Jun 2009 23:13:10 -0400 Subject: [time-nuts] Thunderbolts, time references, NTP etc. In-Reply-To: References: Message-ID: On Jun 15, 2009, at 9:07 AM, Dave Baxter wrote: > Is this good value, and a trusted seller? I know nothing about the seller, but the price (US $159) looks reasonable, considering the inclusion of the antenna and power supply. > My intended main application, is to drive a local NTP server (Network > Time Protocol) as I'm getting more and more P'd off with my ISP's > ineptitude in maintaining a network where NTP (or anything else not > related to web crawling or email) works with any reliability. (Huge > and > variable latency, ping to ping, at different times of day, confirmed > by > other users of the same ISP.) > > I run (just because I can!) a HF beacon monitor station, running the > Faros software from Alex VE3NEA. That uses NTP and only NTP to > synchronise it's software clock. (http://www.dxatlas.com/Faros/) The > results of that can be seen at http://g8kbv.homeip.net:8008/ The > white > delay spots illustrate where the NTP source is messed up. > > The 10MHz output would perhaps be useful, once I have modified a radio > or two to use that as a reference for their synthesizers, but that is > not necessary as yet. I had a GPS with a 1pps output, but due to a > PSU > malfunction, it doesnt work any more sadly. :-( > > Mind you, I'm, still having difficulty configuring a FreeBSD box for > NTP > server use. The instructions to do so I have are good it seems > (http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm) just that the system > does not seem to co-operate, and I'm not that familiar with > Linux/FreeBSD etc at the basic user level, let alone re-compiling the > kernel. As evidenced by a non booting system, the two times I > eventually got it to compile (that takes hours to complete) and that > was > not even with modified sources, just what came on the CD > unmolested. As > each reload takes an age, I sort of lost the plot with that method! You should be able to get an operating NTP configuration off of the stock FreeBSD install. Please note that the web page you cited is somewhat outdated, the current production FreeBSD release is 7.2. The first thing I would suggest is to get a default FreeBSD install running with NTP using servers from the internet (if you're in the UK I would start with the UK NTP pool servers 0.uk.pool.ntp.org, 1.uk.pool.ntp.org, etc.). You should be able to do this without any recompiling. Once you have the FreeBSD system operating with NTP I would then work on the GPS synchronization. Note that the Thunderbolt PPS width is 10 microseconds, and for PPS detection to work on a FreeBSD serial port the pulse should be on the order of a couple of milliseconds wide. You can use a pulse stretcher, such as the TAPR FatPPS (http://www.tapr.org/kits_fatpps.html ) to generate a long enough pulse. Using PC hardware, with FreeBSD you should be able to get the NTP server synchronized within a few tens of microseconds of UTC, using PPS into the serial port. You may also consider a device such as the Garmin GPS18 if all you want is an economical stratum 1 time server. > The local Linux User Group is not that much help either, no one has > any > experience with this sort of "engineering" thing. > > Ultimately, I'd like to run something like this on a non-PC hardware > platform. Now you get into the fun stuff. A device such as the Soekris Net4501 (124 Euro, US $148 new) makes a wonderful NTP server. Unmodified it works quite well. One simple hardware modification allows much more precise timestamping of the PPS, allowing synchronization within a couple microseconds. Going further, replacing the stock crystal with a precision frequency source, which you can derive from the Thunderbolt's 10 MHz, will allow the NTP server to synchronize itself within 150 ns. John Ackerman describes this at . I have built one based on John's description, with a few alterations, and it works extremely well. First things first, though. For a beginner I would: 1) NTP synchronized to internet servers using stock FreeBSD install, 2) then get NTP working with PPS, 3) Then look at embedded-type device such as Net4501. I, and I'm sure there are others here, would be happy to help with any questions, going off-list if need be to avoid cluttering the list. Ralph From mcleann at bigpond.com Tue Jun 16 03:23:22 2009 From: mcleann at bigpond.com (Nic McLean) Date: Tue, 16 Jun 2009 13:23:22 +1000 Subject: [time-nuts] Thunderbolts, time references, NTP etc. In-Reply-To: <4A370DAE.4050605@WA5ZNU.org> References: <4A370DAE.4050605@WA5ZNU.org> Message-ID: Have a look at 300290607038. Regards, Nic It's "fluke.l" not "flukel" who I've dealt with quite recently, and many other more venerable folks on this list have commented on as well. Leigh. > Is this good value, and a trusted seller? > > I went looking for "Fluke1" as listed earlier on here for these devices > (Thunderbolt GPS disciplined referenced sources) but though I > (eventually) found the user, no activity was shown for some time. So, I > went looking for the product instead, and found (among other things) > this item 170344432395 (you know where to look.) > ... > Dave B. > G0WBX. From kilodelta4foxmike at gmail.com Tue Jun 16 03:51:15 2009 From: kilodelta4foxmike at gmail.com (Brian Kirby) Date: Mon, 15 Jun 2009 22:51:15 -0500 Subject: [time-nuts] manual request. In-Reply-To: <1693.75.163.170.128.1245120424.squirrel@www.frequencystandards.com> References: <1693.75.163.170.128.1245120424.squirrel@www.frequencystandards.com> Message-ID: <4A3716B3.6070303@gmail.com> Corby Dawson, who is on this list, has a copy. service at frequencystandards.com wrote: > I have had a request for a manual for BALL Efratom Division Portable Clock > Model PC-10. I will put you in direct contact with them if you have one. > They are willing to pay for a copy of it. > Thanks, Chuck Norton > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From sar10538 at gmail.com Tue Jun 16 06:07:32 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Tue, 16 Jun 2009 18:07:32 +1200 Subject: [time-nuts] Thunderbolts, time references, NTP etc. In-Reply-To: References: Message-ID: <1231b6a80906152307k588821dag6259c66f40f5566a@mail.gmail.com> If you can find one, a Truetime NTS-90/-100/-150/-200 server makes a good ready to go NTP server in a rack mount format. I have a NTS-90 which works a treat and is managed via a console link, telnet, or a web page (my one only seems to like IE with the Microsoft version of Java to control it, grrrrr!). The higher spec models also have front panel controls. 73, Steve 2009/6/16 Dave Baxter : > Is this good value, and a trusted seller? > > I went looking for "Fluke1" as listed earlier on here for these devices > (Thunderbolt GPS disciplined referenced sources) but though I > (eventually) found the user, no activity was shown for some time. ?So, I > went looking for the product instead, and found (among other things) > this item 170344432395 (you know where to look.) > > My intended main application, is to drive a local NTP server (Network > Time Protocol) as I'm getting more and more P'd off with my ISP's > ineptitude in maintaining a network where NTP (or anything else not > related to web crawling or email) works with any reliability. ?(Huge and > variable latency, ping to ping, at different times of day, confirmed by > other users of the same ISP.) > > I run (just because I can!) a HF beacon monitor station, running the > Faros software from Alex VE3NEA. ?That uses NTP and only NTP to > synchronise it's software clock. ?(http://www.dxatlas.com/Faros/) ?The > results of that can be seen at http://g8kbv.homeip.net:8008/ ?The white > delay spots illustrate where the NTP source is messed up. > > The 10MHz output would perhaps be useful, once I have modified a radio > or two to use that as a reference for their synthesizers, but that is > not necessary as yet. ? I had a GPS with a 1pps output, but due to a PSU > malfunction, it doesnt work any more sadly. ?:-( > > Mind you, I'm, still having difficulty configuring a FreeBSD box for NTP > server use. ? The instructions to do so I have are good it seems > (http://www.satsignal.eu/ntp/FreeBSD-GPS-PPS.htm) just that the system > does not seem to co-operate, and I'm not that familiar with > Linux/FreeBSD etc at the basic user level, let alone re-compiling the > kernel. ?As evidenced by a non booting system, the two times I > eventually got it to compile (that takes hours to complete) and that was > not even with modified sources, just what came on the CD unmolested. ?As > each reload takes an age, I sort of lost the plot with that method! > > The local Linux User Group is not that much help either, no one has any > experience with this sort of "engineering" thing. > > Ultimately, I'd like to run something like this on a non-PC hardware > platform. > > > Does anyone on this list know of a ready to run appliance, or > preconfigured boot CD of this sort? ? Providing a LAN NTP source from > GPS, for not much more than the cost of one of the Thunderbolts or > similar? ? There are lots of commercial offerings, but way outside my > price budget, this is for a hobby after all. > > Changing ISP would be a hassle, and there is no garantee that any other > ISP wouldnt do the same silly thing, seemingly throttling private users > WAN traffic during the day, though they say they don't. ?The ISP support > people didnt even know what NTP was when I contacted them, then said > that so long as there were no lost packets, ping delays of up to 250ms > were acceptable!! > > Half the trouble seems to be, as a result of them appearing to now be > running their NTP servers on the same machines as their border gateway > systems, based on IP addresses and service names. > > Ideas anyone? > > Regards. > > Dave B. > G0WBX. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From didier at cox.net Tue Jun 16 08:03:23 2009 From: didier at cox.net (Didier Juges) Date: Tue, 16 Jun 2009 03:03:23 -0500 Subject: [time-nuts] [Mw] Efratom 10MHZ Rubidium FREQUENCY Standard FRS-C In-Reply-To: <001201c9ee26$8212fc20$8638f460$@net> References: <001201c9ee26$8212fc20$8638f460$@net> Message-ID: <4092CE753B5245958AFC328BA35C7100@d400> http://www.ko4bb.com/Manuals/05)_GPS_Timing/Efratom/Efratom_FRS-C_Rubidium_O scillator.pdf Didier KO4BB > -----Original Message----- > From: microwave-bounces at lists.valinet.com > [mailto:microwave-bounces at lists.valinet.com] On Behalf Of Randy Bynum > Sent: Monday, June 15, 2009 9:03 PM > To: microwave at echo.valinet.com > Subject: [Mw] Efratom 10MHZ Rubidium FREQUENCY Standard FRS-C > > Does anyone have the pin connections for this frequency > standard? There is a male DB-25 connector on it and the box > has the 3 TNC female RF connectors. > All in a box about 4X4X3. > > > > Thanks, > > > > Randy Bynum, NR6CA > > Reno, NV DM09cj > > Soda Springs, CA CM99th > > 160 meters to 80 GHz plus laser > > http://www.nr6ca.org > > > > _______________________________________________ > Microwave mailing list > microwave at lists.valinet.com > http://www.valinet.com/mailman/listinfo/microwave > From hmurray at megapathdsl.net Tue Jun 16 08:32:49 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Tue, 16 Jun 2009 01:32:49 -0700 Subject: [time-nuts] test mailing from a new member In-Reply-To: Message from David Bengtson of "Mon, 15 Jun 2009 22:20:08 EDT." Message-ID: <20090616083250.21347BCEF@ip-64-139-1-69.sjc.megapath.net> david.bengtson at gmail.com said: > I've recently gotten an opportunity to work on a GPSDO at work, and > so I now have a real need to pick up some more information on the > design tradeoffs and approaches in a GPSDO. I've plowed through a pile > of old emails, but it's difficult to get a good overview from email > threads. > I would appreciate links to discussions on the tradeoffs inherent in a > GPSDO. Sampling clock rate, filter bandwidths, jitter requirements Be sure you know about hanging bridges. Start with the "Timing for VLBI" slides at http://gpstime.com/ -- These are my opinions, not necessarily my employer's. I hate spam. From GandalfG8 at aol.com Tue Jun 16 09:48:28 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 16 Jun 2009 05:48:28 EDT Subject: [time-nuts] [Mw] Efratom 10MHZ Rubidium FREQUENCY Standard FRS-C Message-ID: In a message dated 16/06/2009 09:04:25 GMT Daylight Time, didier at cox.net writes: > -----Original Message----- > From: microwave-bounces at lists.valinet.com > [mailto:microwave-bounces at lists.valinet.com] On Behalf Of Randy Bynum > Sent: Monday, June 15, 2009 9:03 PM > To: microwave at echo.valinet.com > Subject: [Mw] Efratom 10MHZ Rubidium FREQUENCY Standard FRS-C > > Does anyone have the pin connections for this frequency > standard? There is a male DB-25 connector on it and the box > has the 3 TNC female RF connectors. > All in a box about 4X4X3. ------------- I didn't see this message until Didier posted his reply but this sounds like it could be the Lucent module containing the FRS itself plus two interface boards. If it is then I asked a similar question recently and Bill Ezell was kind enough to provide the connection information for the DB25 which I'll forward to the list again after sending this to save you having to look for it in the archives. Note that Bill's list describes pin 20 as ground but on my unit it links to an internal resister, purpose unknown, and not ground. The only connections I've used are the +24 power connections on pins 1 and 2, and ground on pins 3 and 4. The only advantage I found in using the complete module, or the PCBs in my case as I don't have the box, was havng the RF output provided on one of the TNC connectors rather than having to rely on a take off point from the interface PCB that connects directly to the FRS. The interface board with the DB25 and TNCs serves no other obvious useful purpose if only wanting to use the FRS and it adds 200 to 300 mA to the supply current. In the longer term, if this is the same unit, I would recommend not using either of the PCBs but removing the FRS mating connector from the otherwise unpopulated "bridge" PCB and using that to make direct connections to the FRS itself. Didier's manual will have all the necessary information for that. As per the assorted and very wide ranging recent discussions, the FRS should be mounted on some form of heatsink:-) This applies even if kept in that outer box, Viewing the unit on the connectors with the DB25 at the top, as marked on the PCB the DB25 is J1, the bottom left hand TNC is J2, the middle TNC is J4, and the right hand TNC, slightly above the others, is J3. TNC connections are.... J2 -- 15MHz output when used in original Lucent kit. J3 -- Direct connection to FRS 10MHz output. J4 -- Also 10 MHz output. Bill describes it as buffered, I metered 50 ohms between this and J3 when unpoweredso not sure if it's actively buffered or just padded. The 25 pin details to follow, and if this isn't the same module then humble apologies in advance for the wasted bandwidth:-) regards Nigel GM8PZR From GandalfG8 at aol.com Tue Jun 16 09:50:36 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 16 Jun 2009 05:50:36 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: Bill's connection info for Lucent FRS module, forwarded as agreed. Nigel GM8PZR In a message dated 02/06/2009 02:11:10 GMT Daylight Time, wje at quackers.net writes: Much to my amazement, I did find some notes on the DB-25 15Mhz board pinout: 1 +24V 2 +24V 3 Gnd 4 Gnd 5 6 Freq Adj (this goes directly to the FRS, the board does nothing with it) 7 Gnd 8 -Enable + 9 10 Enable - (notes are unclear on 8, 10, 11, 12. See note below) 11 To 11 on other unit 12 to Fault+ on other unit 13 External 1 (this goes to whatever the dual-osc unit plugs into, function unknown) 14 15 External 2 16 Fault + 17 Fault - 18 Ready + 19 Ready - 20 Gnd 21 Standby + 22 Standby - 23 24 25 Pins with no assignment are not used. Note - as mentioned in the previous post, two units cross-monitor each other. One is selected as primary by a manual switch. The notes I found didn't cover the details, but if I remember correctly, +/- enable selects the primary (one unit is enabled, one disabled). Then, a fault assertion by the primary will cause the secondary to become primary. The secondary's 15Mhz output is disabled; only the primary provides an output. The control lines are all TTL compatible, and are always provided in complimentary pairs. Finally, these pinouts came from tracing a live unit and observing behavior. They might not be completely accurate, but they're close. Bill Ezell ---------- They said 'Windows or better' so I used Linux. GandalfG8 at aol.com wrote: > > In a message dated 01/06/2009 02:23:46 GMT Daylight Time, wje at quackers.net > writes: > > I did at one time have the connector pinout info, but since the board is > fairly useless, I'm not sure I kept it. It does have some nice TNC > connectors and a nice crystal filter, if you happen to need a 15Mhz > filter. > > > > ----------- > Hi Bill > > I did realise, after my posted request, that what was described in the > auction as a 15MHz oscillator was actually a 15MHz filter with 36KHz bandwidth. > Not sure that I need one either:-), but if you do still have the connector > pinout I'd be grateful for a copy. > > regards > > Nigel > GM8PZR > > From rexa at sonic.net Tue Jun 16 10:24:46 2009 From: rexa at sonic.net (Rex) Date: Tue, 16 Jun 2009 03:24:46 -0700 Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: References: Message-ID: <4A3772EE.4040004@sonic.net> I posted this in reply to the original question in the Microwave list... What you are describing is not an FRS-C but a box that contains an FRS-C. I think it was some kind of Telco package. The box produces versions of the 10 MHz from the FRS-C on two of the TNC's and a 15 MHz sine generated from the 10 MHz on the third. I bought one of these in 2004 and did some digging to try to figure out what is inside. The results of this are in a document I created, here: ftp://ftp.sonic.net/pub/users/rexa/FRSrubidium/rubid_notes.pdf There's a version of the FRS-C manual in that same FTP directory. My recollection is that the FRS-C is not very clean in phase noise. The document should have all you need to get it working. If you learn any more about what the mystery pins (11 - 25 on the DB-25) might have been for, I'd be interested to hear about it. -Rex, kk6mk I see from the pin-out below, that some of the unknown pin signals have been given names. Good to know. GandalfG8 at aol.com wrote: > >Bill's connection info for Lucent FRS module, forwarded as agreed. >Nigel GM8PZR > >In a message dated 02/06/2009 02:11:10 GMT Daylight Time, wje at quackers.net >writes: > >Much to my amazement, I did find some notes on the DB-25 15Mhz board >pinout: > >1 +24V >2 +24V >3 Gnd >4 Gnd >5 >6 Freq Adj (this goes directly to the FRS, the board does nothing with it) >7 Gnd >8 -Enable + >9 >10 Enable - (notes are unclear on 8, 10, 11, 12. See note below) >11 To 11 on other unit >12 to Fault+ on other unit >13 External 1 (this goes to whatever the dual-osc unit plugs into, >function unknown) >14 >15 External 2 >16 Fault + >17 Fault - >18 Ready + >19 Ready - >20 Gnd >21 Standby + >22 Standby - >23 >24 >25 > >Pins with no assignment are not used. > >Note - as mentioned in the previous post, two units cross-monitor each >other. One is selected as primary by a manual switch. The notes I found >didn't cover the details, but if I remember correctly, +/- enable >selects the primary (one unit is enabled, one disabled). Then, a fault >assertion by the primary will cause the secondary to become primary. The >secondary's 15Mhz output is disabled; only the primary provides an output. > >The control lines are all TTL compatible, and are always provided in >complimentary pairs. > >Finally, these pinouts came from tracing a live unit and observing >behavior. They might not be completely accurate, but they're close. > >Bill Ezell >---------- >They said 'Windows or better' >so I used Linux. > > > >GandalfG8 at aol.com wrote: > > >> >>In a message dated 01/06/2009 02:23:46 GMT Daylight Time, >> >> >wje at quackers.net > > >>writes: >> >>I did at one time have the connector pinout info, but since the board >> >> >is > > >>fairly useless, I'm not sure I kept it. It does have some nice TNC >>connectors and a nice crystal filter, if you happen to need a 15Mhz >>filter. >> >> >> >> ----------- >>Hi Bill >> >>I did realise, after my posted request, that what was described in the >>auction as a 15MHz oscillator was actually a 15MHz filter with 36KHz >> >> >bandwidth. > > >>Not sure that I need one either:-), but if you do still have the >> >> >connector > > >>pinout I'd be grateful for a copy. >> >>regards >> >>Nigel >> GM8PZR >> >> >> >> > > > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > > > From GandalfG8 at aol.com Tue Jun 16 11:49:58 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 16 Jun 2009 07:49:58 EDT Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board Message-ID: Hi Rex Looking again at Didier's email, and the copy there of the original question, I can understand now why I never saw that original request and why I really was wasting bandwidth by answering it here, it looks like Didier posted his reply here to a question from elsewhere, thanks Didier:-) You have at least confirmed that what I assumed seems correct and thanks for the link to your pdf file, that's a bit more useful information. regards Nigel GM8PZR In a message dated 16/06/2009 11:25:19 GMT Daylight Time, rexa at sonic.net writes: I posted this in reply to the original question in the Microwave list... What you are describing is not an FRS-C but a box that contains an FRS-C. I think it was some kind of Telco package. The box produces versions of the 10 MHz from the FRS-C on two of the TNC's and a 15 MHz sine generated from the 10 MHz on the third. I bought one of these in 2004 and did some digging to try to figure out what is inside. The results of this are in a document I created, here: ftp://ftp.sonic.net/pub/users/rexa/FRSrubidium/rubid_notes.pdf There's a version of the FRS-C manual in that same FTP directory. My recollection is that the FRS-C is not very clean in phase noise. The document should have all you need to get it working. If you learn any more about what the mystery pins (11 - 25 on the DB-25) might have been for, I'd be interested to hear about it. -Rex, kk6mk From mpb45 at clanbaker.org Tue Jun 16 12:57:21 2009 From: mpb45 at clanbaker.org (Michael Baker) Date: Tue, 16 Jun 2009 08:57:21 -0400 Subject: [time-nuts] Glass is not a liquid but has some similar molecular similarities Message-ID: <4A3796B1.5060502@clanbaker.org> Hello, Time Nuts-- For those of you following the thread on glass properties, see: Dual personality of glass explained at last Mike Baker ----------------------------------- See the entire article at: [1]http://tinyurl.com/mqsrjo [2]http://www.newscientist.com/ * 18:00 22 June 2008 by Colin Barras snip Although glass feels like a solid, its molecules cannot quite settle into a regular 3D lattice, instead taking on the disordered arrangement of a liquid. Quite why glass behaves like this has been unclear. snip This geometry is incapable of slotting together, or tessellating, to form the regular 3D lattice characteristic of a solid. But equally they cannot move around freely because they are larger than the original particles. snip Royall thinks that the molecules of real glass takes on the same icosahedral structure, leaving it unable to crystallise into a solid, but not free enough to have liquid-like properties. 'Metallic glass' snip "For a long time, no-one has really shown what the structure of glass is," Royall says, "but we have been able to show how the structure of a glass differs from that of a liquid." References 1. http://tinyurl.com/mqsrjo 2. http://www.newscientist.com/ From jmiles at pop.net Tue Jun 16 13:48:32 2009 From: jmiles at pop.net (John Miles) Date: Tue, 16 Jun 2009 06:48:32 -0700 Subject: [time-nuts] Datum 9390 firmware Message-ID: Has anyone been able to come up with a burnable EPROM image for the new Datum 9390 firmware that's supposed to fix the GPS day # bug? Before I start delving into the phone tree at Symmetricom, I thought I'd ask if anyone who's received one of the new EPROMs has read it yet. -- john, KE5FX From cfharris at erols.com Tue Jun 16 14:34:39 2009 From: cfharris at erols.com (Chuck Harris) Date: Tue, 16 Jun 2009 10:34:39 -0400 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> Message-ID: <4A37AD7F.1090806@erols.com> J. Forster wrote: > Interestingly, I recently had dinner with an archeology professor, > interested in the Etruscan period. She had just discovered a flatish piece > of glass i9n a dig, thousands of years old, and believes it was made > essentially like rolling out dough on a slab while red hot. To me, it would seem that playing with a blob of molten glass in a fire, and spreading it out, or rolling it would be a more natural step in the progression of making glass windows than blowing a bubble. I would strongly expect that the earliest windows would have been made by rolling the molten glass flat like it was dough. Much later would have come the blowing of a cylinder, and flattening it out. In any case, there is zero evidence that glass flows at room temperature. If it did, and 180 years was all it took for a window pane to become all wavy, and thicken at the bottom, all of those 10,000 year old glass artifacts would be shaped like the chewing gum blobs on a city sidewalk. -Chuck Harris From henk.termeer at gmail.com Tue Jun 16 15:01:08 2009 From: henk.termeer at gmail.com (Henk Termeer) Date: Tue, 16 Jun 2009 17:01:08 +0200 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <4A37AD7F.1090806@erols.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> <4A37AD7F.1090806@erols.com> Message-ID: <5323a8e30906160801i2b440983x1df96b214a792f6d@mail.gmail.com> A better explanationcan be found in the wiki On Tue, Jun 16, 2009 at 4:34 PM, Chuck Harris wrote: > J. Forster wrote: > >> Interestingly, I recently had dinner with an archeology professor, >> interested in the Etruscan period. She had just discovered a flatish piece >> of glass i9n a dig, thousands of years old, and believes it was made >> essentially like rolling out dough on a slab while red hot. >> > > To me, it would seem that playing with a blob of molten glass in > a fire, and spreading it out, or rolling it would be a more natural > step in the progression of making glass windows than blowing > a bubble. > > I would strongly expect that the earliest windows would have been > made by rolling the molten glass flat like it was dough. > > Much later would have come the blowing of a cylinder, and flattening > it out. > > In any case, there is zero evidence that glass flows at room > temperature. If it did, and 180 years was all it took for a window > pane to become all wavy, and thicken at the bottom, all of those > 10,000 year old glass artifacts would be shaped like the chewing > gum blobs on a city sidewalk. > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- ---------------------------------------------------------------------------------------------------- "Je hoeft het niet met elkaar eens te zijn om naar elkaar te luisteren." Ook van Loesje ---------------------------------------------------------------------------------------------------- From bg at lysator.liu.se Tue Jun 16 15:43:45 2009 From: bg at lysator.liu.se (bg at lysator.liu.se) Date: Tue, 16 Jun 2009 17:43:45 +0200 (CEST) Subject: [time-nuts] Efratom FRS 10mhz rubidium frequency oscillator+ board In-Reply-To: <4A3772EE.4040004@sonic.net> References: <4A3772EE.4040004@sonic.net> Message-ID: <56788.87.227.52.225.1245167025.squirrel@webmail.lysator.liu.se> > My recollection is that the FRS-C is not very clean in phase noise. The > document should have all you need to get it working. If you learn any > more about what the mystery pins (11 - 25 on the DB-25) might have been > for, I'd be interested to hear about it. > > -Rex, kk6mk I have an FRS-C running in the stainless(?) box giving two 10MHz and one 15MHz TNC outputs. Mine FRS-C is an TTL output version. It is not giving a sine output. -- Bj?rn From phk at phk.freebsd.dk Tue Jun 16 15:52:06 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Tue, 16 Jun 2009 15:52:06 +0000 Subject: [time-nuts] Lifetime of glass containers In-Reply-To: Your message of "Tue, 16 Jun 2009 10:34:39 -0400." <4A37AD7F.1090806@erols.com> Message-ID: <3314.1245167526@critter.freebsd.dk> In message <4A37AD7F.1090806 at erols.com>, Chuck Harris writes: >J. Forster wrote: >To me, it would seem that playing with a blob of molten glass in >a fire, and spreading it out, or rolling it would be a more natural >step in the progression of making glass windows than blowing >a bubble. The problem is that you don't get very clear glass using any kind of surface, because pretty much everything you can think of using for the base will contaminate the glass, either as particulate matter or chemically. The history in reverse is something like: Some (french ?) guy figured out that tin (Sn) did not chemically react with glass and used a liquid bath of it as base that a "float" glass process which produces clear consistent glass with very few refractory variations. In float glass, imperfections are mostly particles which cause "sombreo" like refractory imperfections. Practically all windowglass is produced this way today. Before the float process, drawn glass was used, basically pulling a membrane of glass out of bath of molten glass. This required quite a bit "fingerspitzgef?hl" and special buildings which could control the temperature gradient very precisely. The resulting glass very often had straight lines of refractory variations in the drawn direction and significant thickness variations. I belive this process has never been done manually or with animal power, only with machinepower. Before the "drawn" glass, window glass was "blown" by picking up a lump of molten glass on a steel rod and twirling it as fast as possible (often on special "tables" consisting of two steel bars set in parallel), making the centrifugal force draw the solidifying glass into a disc. Thinking about pizza dough here is entirely appropriate. The disc were subsequently cut into rectangular pieces, and the glass is easily recognizable because of the numerous and significant arc-shaped refractory variations. In general it was very hard to get a diameter above approx 2 feet with this method. To my knowledge, this process has never been mechanized, power from horses has been used. Archeologists have found two kinds of *flat* glass predating this, one bearing evidence of simply being molten glass poured out over a flat, possibly heatet, marble slab. Some of this glass has had the resulting opaque layer polished off, at great expense and effort. The other kind is the "rolled glass", where molten glass has been poured out through a narrow slot and subseqently rolled further, like dough for a flatcakes can be recognized by having both sides having an opaque layer. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From gwinn at raytheon.com Tue Jun 16 15:53:19 2009 From: gwinn at raytheon.com (Joseph M Gwinn) Date: Tue, 16 Jun 2009 11:53:19 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <35DF68EA-9D09-4CB1-995A-318F4E448FA1@gmail.com> Message-ID: time-nuts-bounces at febo.com wrote on 06/15/2009 06:08:58 PM: > hi, > the main point of the water approach was the high performance of > water as a heat storage medium. > Quartz, if one can assume that is what pebbles are made of, has a > density of 2.7 g/cc but a specific > heat of only 0.2 cal/gm C. > That is only 0.54 cal/cc C compared to water with a figure of 1.0. > So water still has greater merit as a thermal buffer. > Cheers, Neville Michie Yep. But it's runny. I have a modest proposal to combine the benefits of water and silica: We will use wine bottles in the bottom of the cooler as thermal masses. Sadly, any bottle showing any signs of leakage whatsoever will have to be replaced, the leaking bottle being uncorked and the contents tested. At length. Joe Gwinn > > > On 16/06/2009, at 2:30 AM, Joseph M Gwinn wrote: > > > time-nuts-bounces at febo.com wrote on 06/15/2009 06:57:13 AM: > > > >> They suggest you add a small amount of chlorine bleach to water > >> containers you store for natural disaster emergencies. You also need > >> to replace the water on a regular basis even with the bleach in it. > >> Here in Christchurch, New Zealand, they don't even chlorinate the > >> water we drink, it comes straight out of a natural aquifer underneath > >> us. As for the long term effects of bleach on plastic bottles, one > >> would imagine that it would accelerate the breakdown of the plastic. > >> Interestingly, someone in the know, talking about land-fill sites, > >> suggested that there is essentially no breakdown of these items when > >> they are fully embeded in the fill. Luckily we recycle almost > >> everything here but it would make interesting finds for future > >> archaeologists. > >> > >> A glass vessel with a stabilised rubber stopper or lapped glass > >> stopper and wax sealed would seemingly be better for long term use > >> and > >> the glass should conduct the heat better than plastic for our xtal > >> oven ballast. But glass is not a solid, it's a liquid after all and > >> would eventually find the lowest point with time. Mind you, that is a > >> very long time. The other thing that comes to mind is that > >> state-change salt type of liquid that absorbs energy well. Of course, > >> you could use an eskey if it was not holding the beer and may be a > >> less smelly alternative than a used fridge at room temp. > > > > I was the one who originally rained on the use-water-in-a-bottle > > approach. > > The response was that even a child could store water. Well, that > > is not > > the common experience with water-cooled equipment, which always > > manages to > > require continual maintenance attention, so I went quiet, and > > listened as > > the subject was explored. > > > > It has become apparent from the issues and increasingly complex > > schemes to > > solving tose issues that keeping water in its place is not exactly > > child's > > play, and it seems to me that water is far more trouble and even > > expense > > than simply getting a big hunk of scrap metal, unless one needs > > tons of > > thermal mass. If one needs fast thermal exchange with the air, > > drill some > > holes or use a set of thick plates with spacers, so the distance > > from air > > to the most remote part of the mass is no more than an inch or so. > > Or, > > use a big hunk of copper or aluminum. Or both. > > > > If one needs tons of thermal mass plus rapid exchange with the air, > > use > > brick checkerwork or a pebble bed, a standard industrial approach: < > > http://en.wikipedia.org/wiki/Regenerator>. For thermal > > stabilization of > > timekeeping equipment, a pebble bed and a circulating fan is cheap and > > easy. > > > > Joe Gwinn > > > > > >> 73, > >> Steve > >> > >> 2009/6/15 Didier Juges : > >>> Here in Florida, we routinely store water in prevision of the > >> next big one. > >>> > >>> Plastic water bottles (any brand) start looking funny > >> (shrunk) after a few > >>> months, and downright scary (as in: you don't want to drink > >> from THAT) after > >>> a year or so. > >>> > >>> It seems the gallon jugs do somewhat better than the smaller > >> bottles. I had > >>> jugs that still looked OK after a year, but not good after > >> two. The pastic > >>> seems much thicker, and maybe it slows down the process? > >>> > >>> It's been like that for as long as I have lived here, i.e. > >> since 1985. I do > >>> not know if it is related to the climate. It makes no > >> appreciable difference > >>> if the water is stored in the garage (no A/C) or in the house. > >>> > >>> Didier KO4BB > >>> > >>>> -----Original Message----- > >>>> From: time-nuts-bounces at febo.com > >>>> [mailto:time-nuts-bounces at febo.com] On Behalf Of Thomas A. Frank > >>>> Sent: Saturday, June 13, 2009 12:16 PM > >>>> To: Discussion of precise time and frequency measurement > >>>> Subject: Re: [time-nuts] Thunderbolt stability and ambient > > temperature > >>>> > >>>> More to the point, you will be disappointed to find the bottles > >>>> will > >>>> NOT last that long. > >>>> > >>>> Cleaning out the cupboard recently, I can across some bottled water > >>>> that had 1998 date codes. Several had leaked, but one was still > >>>> intact enough to show the likely problem. It would appear that > >>>> over > >>>> the past 10 years, the gases dissolved in the water migrated > >>>> through > >>>> the plastic (or the cap seal), resulting in a vacuum forming in the > >>>> bottle. This distended the bottles and caused structural failure. > >>>> > >>>> Either that, or the water caused the plastic to shrink. > >>>> > >>>> Glass would probably fair better. > >>>> > >>>> Tom Frank, KA2CDK > >>>> > >>> > >>> > >>> _______________________________________________ > >>> time-nuts mailing list -- time-nuts at febo.com > >>> To unsubscribe, go to https://www.febo.com/cgi- > >> bin/mailman/listinfo/time-nuts > >>> and follow the instructions there. > >>> > >> > >> > >> > >> -- > >> Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW > >> A man with one clock knows what time it is; > >> A man with two clocks is never quite sure. > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts at febo.com > >> To unsubscribe, go to https://www.febo.com/cgi- > >> bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > >> > >> The following line is added for your protection and will be > >> used for analysis if this message is reported as spam: > >> > >> (Raytheon Analysis: IP=64.34.164.147; e-from=time-nuts- > >> bounces+gwinn=raytheon.com at febo.com; from=sar10538 at gmail.com; > >> date=Jun 15, 2009 10:59:08 AM; subject=Re: [time-nuts] > >> Thunderbolt stability and ambient temperature) > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > > time-nuts > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > and follow the instructions there. > > The following line is added for your protection and will be > used for analysis if this message is reported as spam: > > (Raytheon Analysis: IP=64.34.164.147; e-from=time-nuts- > bounces+gwinn=raytheon.com at febo.com; from=namichie at gmail.com; > date=Jun 15, 2009 10:10:20 PM; subject=Re: [time-nuts] > Thunderbolt stability and ambient temperature) From gsteinba52 at aol.com Tue Jun 16 16:00:29 2009 From: gsteinba52 at aol.com (gsteinba52 at aol.com) Date: Tue, 16 Jun 2009 12:00:29 -0400 Subject: [time-nuts] Glass / Metal - it all flows Message-ID: <8CBBCB2B4B9BD78-B74-115B@FWM-M36.sysops.aol.com> Hopefully this will end the argument with a time-nuts flavor: http://www.msdlists.com/surrealism/images/full%20size/Dali%20Persistence%20of%20Time.jpg Jerry From cfharris at erols.com Tue Jun 16 17:31:33 2009 From: cfharris at erols.com (Chuck Harris) Date: Tue, 16 Jun 2009 13:31:33 -0400 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A37D6F5.6090608@erols.com> Joseph M Gwinn wrote: >> That is only 0.54 cal/cc C compared to water with a figure of 1.0. >> So water still has greater merit as a thermal buffer. >> Cheers, Neville Michie > > Yep. But it's runny. > > I have a modest proposal to combine the benefits of water and silica: We > will use wine bottles in the bottom of the cooler as thermal masses. > Sadly, any bottle showing any signs of leakage whatsoever will have to be > replaced, the leaking bottle being uncorked and the contents tested. At > length. Hear! Hear! I vote for a continuous cycle of testing. We dare not allow even the beginnings of a leak to appear. I volunteer as chief tester. -Chuck Harris From jfor at quik.com Tue Jun 16 17:40:51 2009 From: jfor at quik.com (J. Forster) Date: Tue, 16 Jun 2009 10:40:51 -0700 (PDT) Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <5323a8e30906160801i2b440983x1df96b214a792f6d@mail.gmail.com> References: <20090615192341.3DA40BCEF@ip-64-139-1-69.sjc.megapath.net> <88540FDC0A7944B4823CC630F22D3285@symmetricom.com> <1103.12.6.201.112.1245101661.squirrel@popacctsnew.quik.com> <4A37AD7F.1090806@erols.com> <5323a8e30906160801i2b440983x1df96b214a792f6d@mail.gmail.com> Message-ID: <1333.12.6.201.234.1245174051.squirrel@popacctsnew.quik.com> > A better > explanationcan > be found in the wiki > > On Tue, Jun 16, 2009 at 4:34 PM, Chuck Harris wrote: > >> J. Forster wrote: >> >>> Interestingly, I recently had dinner with an archeology professor, >>> interested in the Etruscan period. She had just discovered a flatish >>> piece >>> of glass i9n a dig, thousands of years old, and believes it was made >>> essentially like rolling out dough on a slab while red hot. >>> >> >> To me, it would seem that playing with a blob of molten glass in >> a fire, and spreading it out, or rolling it would be a more natural >> step in the progression of making glass windows than blowing >> a bubble. >> >> I would strongly expect that the earliest windows would have been >> made by rolling the molten glass flat like it was dough. >> >> Much later would have come the blowing of a cylinder, and flattening >> it out. =========== Agreed. Also remember that in the early days, glass was more likely used to pass light rather than be of image quality. The ability to have light enter a room without an opening in the wall must have been near magical. -John ============= >> >> In any case, there is zero evidence that glass flows at room >> temperature. If it did, and 180 years was all it took for a window >> pane to become all wavy, and thicken at the bottom, all of those >> 10,000 year old glass artifacts would be shaped like the chewing >> gum blobs on a city sidewalk. >> >> -Chuck Harris From jfor at quik.com Tue Jun 16 17:50:04 2009 From: jfor at quik.com (J. Forster) Date: Tue, 16 Jun 2009 10:50:04 -0700 (PDT) Subject: [time-nuts] Lifetime of glass containers In-Reply-To: <3314.1245167526@critter.freebsd.dk> References: <3314.1245167526@critter.freebsd.dk> Message-ID: <1362.12.6.201.234.1245174604.squirrel@popacctsnew.quik.com> Early glass likely did not have to be perfectly clear, but just to transmit light. Here is an interesting (if commercial) site: http://www.glasslinks.com/history.htm -John =========== > In message <4A37AD7F.1090806 at erols.com>, Chuck Harris writes: >>J. Forster wrote: > >>To me, it would seem that playing with a blob of molten glass in >>a fire, and spreading it out, or rolling it would be a more natural >>step in the progression of making glass windows than blowing >>a bubble. > > The problem is that you don't get very clear glass using any kind > of surface, because pretty much everything you can think of using > for the base will contaminate the glass, either as particulate > matter or chemically. [snip] From djl at montana.com Tue Jun 16 19:51:24 2009 From: djl at montana.com (Don Latham) Date: Tue, 16 Jun 2009 13:51:24 -0600 (MDT) Subject: [time-nuts] Glass / Metal - it all flows In-Reply-To: <8CBBCB2B4B9BD78-B74-115B@FWM-M36.sysops.aol.com> References: <8CBBCB2B4B9BD78-B74-115B@FWM-M36.sysops.aol.com> Message-ID: <51d5645d5d159915398db67b34e70625.squirrel@webmail.montana.com> Dali knew: Time itself flows with time? Don gsteinba52 at aol.com > Hopefully this will end the argument with a time-nuts flavor: > > http://www.msdlists.com/surrealism/images/full%20size/Dali%20Persistence%20of%20Time.jpg > > Jerry > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com From jherrero at hvsistemas.es Tue Jun 16 21:50:11 2009 From: jherrero at hvsistemas.es (Javier Herrero) Date: Tue, 16 Jun 2009 23:50:11 +0200 Subject: [time-nuts] Glass / Metal - it all flows In-Reply-To: <51d5645d5d159915398db67b34e70625.squirrel@webmail.montana.com> References: <8CBBCB2B4B9BD78-B74-115B@FWM-M36.sysops.aol.com> <51d5645d5d159915398db67b34e70625.squirrel@webmail.montana.com> Message-ID: <4A381393.3030400@hvsistemas.es> Of course Don Latham escribi?: > Dali knew: Time itself flows with time? > Don > gsteinba52 at aol.com >> Hopefully this will end the argument with a time-nuts flavor: >> >> http://www.msdlists.com/surrealism/images/full%20size/Dali%20Persistence%20of%20Time.jpg >> >> Jerry >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > -- ------------------------------------------------------------------------ Javier Herrero EMAIL: jherrero at hvsistemas.com HV Sistemas S.L. PHONE: +34 949 336 806 Los Charcones, 17A FAX: +34 949 336 792 19170 El Casar - Guadalajara - Spain WEB: http://www.hvsistemas.com From magnus at rubidium.dyndns.org Tue Jun 16 22:04:36 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 00:04:36 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A37D6F5.6090608@erols.com> References: <4A37D6F5.6090608@erols.com> Message-ID: <4A3816F4.4040002@rubidium.dyndns.org> Chuck Harris skrev: > Joseph M Gwinn wrote: > >>> That is only 0.54 cal/cc C compared to water with a figure of 1.0. >>> So water still has greater merit as a thermal buffer. >>> Cheers, Neville Michie >> >> Yep. But it's runny. >> >> I have a modest proposal to combine the benefits of water and silica: >> We will use wine bottles in the bottom of the cooler as thermal >> masses. Sadly, any bottle showing any signs of leakage whatsoever will >> have to be replaced, the leaking bottle being uncorked and the >> contents tested. At length. > > Hear! Hear! > > I vote for a continuous cycle of testing. We dare not allow > even the beginnings of a leak to appear. > > I volunteer as chief tester. I agree. Finally a sound solution I can live with. Naturally we need to sample several bottles to ensure the proper quality level and an even and good temper over each session. Cheers, Magnus From magnus at rubidium.dyndns.org Tue Jun 16 22:07:49 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 00:07:49 +0200 Subject: [time-nuts] test mailing from a new member In-Reply-To: <20090616083250.21347BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090616083250.21347BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A3817B5.5010908@rubidium.dyndns.org> Hal Murray skrev: > david.bengtson at gmail.com said: >> I've recently gotten an opportunity to work on a GPSDO at work, and >> so I now have a real need to pick up some more information on the >> design tradeoffs and approaches in a GPSDO. I've plowed through a pile >> of old emails, but it's difficult to get a good overview from email >> threads. > >> I would appreciate links to discussions on the tradeoffs inherent in a >> GPSDO. Sampling clock rate, filter bandwidths, jitter requirements > > Be sure you know about hanging bridges. Start with the > "Timing for VLBI" slides at http://gpstime.com/ The key issue is, what type of specs is needed? What may it cost? What kind of receiver may be considered? What's the intended application? Cheers, Magnus From james.p.lux at jpl.nasa.gov Tue Jun 16 22:14:40 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 16 Jun 2009 15:14:40 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: <4A3816F4.4040002@rubidium.dyndns.org> References: <4A37D6F5.6090608@erols.com> <4A3816F4.4040002@rubidium.dyndns.org> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Magnus Danielson > Sent: Tuesday, June 16, 2009 3:05 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature > > Chuck Harris skrev: > > Joseph M Gwinn wrote: > > > >>> That is only 0.54 cal/cc C compared to water with a figure of 1.0. > >>> So water still has greater merit as a thermal buffer. > >>> Cheers, Neville Michie > >> > >> Yep. But it's runny. > >> > >> I have a modest proposal to combine the benefits of water > and silica: > >> We will use wine bottles in the bottom of the cooler as thermal > >> masses. Sadly, any bottle showing any signs of leakage whatsoever > >> will have to be replaced, the leaking bottle being > uncorked and the > >> contents tested. At length. > > > > Hear! Hear! > > > > I vote for a continuous cycle of testing. We dare not > allow even the > > beginnings of a leak to appear. > > > > I volunteer as chief tester. > > I agree. Finally a sound solution I can live with. Naturally > we need to sample several bottles to ensure the proper > quality level and an even and good temper over each session. > One might wish to be careful about this process. If the time-nut leading you to the temperature controlled chamber is named Montressor, and the first bottle you sample is Medoc, and he keeps commenting on the efflorescence on the walls,... From magnus at rubidium.dyndns.org Tue Jun 16 22:34:47 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 00:34:47 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: <4A37D6F5.6090608@erols.com> <4A3816F4.4040002@rubidium.dyndns.org> Message-ID: <4A381E07.7020200@rubidium.dyndns.org> Lux, James P skrev: >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Magnus Danielson >> Sent: Tuesday, June 16, 2009 3:05 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature >> >> Chuck Harris skrev: >>> Joseph M Gwinn wrote: >>> >>>>> That is only 0.54 cal/cc C compared to water with a figure of 1.0. >>>>> So water still has greater merit as a thermal buffer. >>>>> Cheers, Neville Michie >>>> Yep. But it's runny. >>>> >>>> I have a modest proposal to combine the benefits of water >> and silica: >>>> We will use wine bottles in the bottom of the cooler as thermal >>>> masses. Sadly, any bottle showing any signs of leakage whatsoever >>>> will have to be replaced, the leaking bottle being >> uncorked and the >>>> contents tested. At length. >>> Hear! Hear! >>> >>> I vote for a continuous cycle of testing. We dare not >> allow even the >>> beginnings of a leak to appear. >>> >>> I volunteer as chief tester. >> I agree. Finally a sound solution I can live with. Naturally >> we need to sample several bottles to ensure the proper >> quality level and an even and good temper over each session. >> > > One might wish to be careful about this process. If the time-nut leading you to the temperature controlled chamber is named Montressor, and the first bottle you sample is Medoc, and he keeps commenting on the efflorescence on the walls,... Depends on the vintage... I might bring my sample glasses in their specially adapted carrying-case. A good Medoc may still be a spoil for my still highly uncalibrated lab, but would be very interesting indeed to sample. Cheers, Magnus From Mark at Misty.com Tue Jun 16 23:38:39 2009 From: Mark at Misty.com (Mark G. Thomas) Date: Tue, 16 Jun 2009 19:38:39 -0400 Subject: [time-nuts] NTS-200 Antenna Power Mod In-Reply-To: <200705191937100818.D30BCBB9@192.168.42.129> References: <200705191937100818.D30BCBB9@192.168.42.129> Message-ID: <20090616233839.GA21270@lucky.misty.com> Hi, On Sat, May 19, 2007 at 07:37:10PM -0700, Bruce Lane wrote: > Fellow clockers, > > I just got done reinstalling my TrueTime NTS-200 network time server in a different rack. This required, among other things, installation of a new antenna on the opposite side of the house from where my original one is. > > The new antenna was a Symmetricom/HP 58532A, which requires 5V bias. Unfortunately, the NTS-200 was designed to supply 12V, and there is no easy jumper or software setting to change that. > > So -- After a bit of work, I came up with a minimally-destructive hardware modification to change the +12 feed to +5. > > If anyone else owns an NTS-200, and you've been wanting to use it with a 5V antenna, drop me a note and I'll be happy to send you pictures and details. > > Fair warning: It requires fine-point soldering, a bit of wire-wrap wire, and a lot of patience. I just got an NTS-200 (12V antenna), and only have 5V HP antennas, so am very interested in this modification. Any detailes would be greatly appreciated. I'd also be interested in talking to any other NTS-200/150/TimeVault owners off-list with some questions about firmware versions. Sorry for posting such an old reply to the list, but Bruce's mail server won't accept my e-mail directly, with a message about Verizon needing to clean up their spammer mess. My mail server is on my own registered IP space and ASN, in no way related to Verizon, but just one of my inbound DNS-listed MX servers is on a static IP from Verizon, and apparently that's enough... Ironically, I run a spam filtering business. Mark -- Mark G. Thomas (Mark at Misty.com) Web: http://mgtinternet.com/ Tel: +1-215-512-0112 US: 877-512-0112 From GandalfG8 at aol.com Wed Jun 17 00:20:05 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 16 Jun 2009 20:20:05 EDT Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: In a message dated 16/06/2009 23:15:50 GMT Daylight Time, james.p.lux at jpl.nasa.gov writes: One might wish to be careful about this process. If the time-nut leading you to the temperature controlled chamber is named Montressor, and the first bottle you sample is Medoc, and he keeps commenting on the efflorescence on the walls,... And still hinting of the Amontillado!! From james.p.lux at jpl.nasa.gov Wed Jun 17 00:30:09 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 16 Jun 2009 17:30:09 -0700 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of GandalfG8 at aol.com > Sent: Tuesday, June 16, 2009 5:20 PM > To: time-nuts at febo.com > Subject: Re: [time-nuts] Thunderbolt stability and ambient temperature > > > In a message dated 16/06/2009 23:15:50 GMT Daylight Time, > james.p.lux at jpl.nasa.gov writes: > > One might wish to be careful about this process. If the > time-nut leading you to the temperature controlled chamber > is named Montressor, and the first bottle you sample is > Medoc, and he keeps commenting on the efflorescence on the walls,... > > > > And still hinting of the Amontillado!! Well.. When one starts talking about bottles and temperature stability, it's the first thing that springs to mind. And I just realized, there's another time-nuts relevant story (even more time-nuts related).. Although I don't believe the pendulum is used for time keeping, especially as it length apparently changes. From magnus at rubidium.dyndns.org Wed Jun 17 00:31:24 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 02:31:24 +0200 Subject: [time-nuts] Thunderbolt stability and ambient temperature In-Reply-To: References: Message-ID: <4A38395C.9050304@rubidium.dyndns.org> GandalfG8 at aol.com skrev: > > In a message dated 16/06/2009 23:15:50 GMT Daylight Time, > james.p.lux at jpl.nasa.gov writes: > > One might wish to be careful about this process. If the time-nut leading > you to the temperature controlled chamber is named Montressor, and the > first bottle you sample is Medoc, and he keeps commenting on the efflorescence > on the walls,... > > > > And still hinting of the Amontillado!! Personally I have a weakness for the Sauternes, but I have not gone crazy with d'Yquem, just like I don't have a few OSA 8607 SC cut BVAs lying around. Cheers, Magnus From magnus at rubidium.dyndns.org Wed Jun 17 00:39:18 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 02:39:18 +0200 Subject: [time-nuts] Ashtech Z12 vs. Z12T Message-ID: <4A383B36.9040400@rubidium.dyndns.org> Fellow time-nuts, Has anyone done a detailed compare on the difference between a Ashtech Z12 and Z12T? I know the basic plot is that the external reference is inserted in place of the internal 20 MHz rather than being PLL locked up. So my questions are: 1) Is that it? Is this the only real difference? 2) How is it achieved in reality? Just how much effort would it be to mod a Z12 to a Z12T? Not being able to compare I just ask the questions openly. Anybody has a Z12T to lend me for a peak inside? Cheers, Magnus From GandalfG8 at aol.com Wed Jun 17 00:42:19 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 16 Jun 2009 20:42:19 EDT Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: In a message dated 17/06/2009 01:31:00 GMT Daylight Time, james.p.lux at jpl.nasa.gov writes: Well.. When one starts talking about bottles and temperature stability, it's the first thing that springs to mind. And I just realized, there's another time-nuts relevant story (even more time-nuts related).. Although I don't believe the pendulum is used for time keeping, especially as it length apparently changes Sounds like the pits if you ask me:-) From GandalfG8 at aol.com Wed Jun 17 00:51:15 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 16 Jun 2009 20:51:15 EDT Subject: [time-nuts] Thunderbolt stability and ambient temperature Message-ID: In a message dated 17/06/2009 01:31:00 GMT Daylight Time, james.p.lux at jpl.nasa.gov writes: Well.. When one starts talking about bottles and temperature stability, it's the first thing that springs to mind. And I just realized, there's another time-nuts relevant story (even more time-nuts related).. Although I don't believe the pendulum is used for time keeping, especially as it length apparently changes. It's probably going to be very good for time keeping. It's not so much that the length is changing as notching downwards second by second with an accurately calibrated scream every half hour:-) From david.bengtson at gmail.com Wed Jun 17 00:59:02 2009 From: david.bengtson at gmail.com (David Bengtson) Date: Tue, 16 Jun 2009 20:59:02 -0400 Subject: [time-nuts] test mailing from a new member In-Reply-To: <4A3817B5.5010908@rubidium.dyndns.org> References: <20090616083250.21347BCEF@ip-64-139-1-69.sjc.megapath.net> <4A3817B5.5010908@rubidium.dyndns.org> Message-ID: On Tue, Jun 16, 2009 at 6:07 PM, Magnus Danielson wrote: > Hal Murray skrev: >> >> david.bengtson at gmail.com said: >>> >>> ?I've recently gotten an opportunity to work on a GPSDO at work, and >>> so I now have a real need to pick up some more information on the >>> design tradeoffs and approaches in a GPSDO. I've plowed through a pile >>> of old emails, but it's difficult to get a good overview from email >>> threads. >> >>> I would appreciate links to discussions on the tradeoffs inherent in a >>> GPSDO. Sampling clock rate, filter bandwidths, jitter requirements >> >> Be sure you know about hanging bridges. ?Start with the >> ?"Timing for VLBI" slides at http://gpstime.com/ > > The key issue is, what type of specs is needed? What may it cost? > What kind of receiver may be considered? What's the intended application? > Specs.. Hmmmm. Good question. The application is for a frequency reference, so frequency stability vs. PPS accuracy is important. Cost is perhaps less important than size. The OCXO under control is a small, surface mount part with +/- 0.5 PPM over temp, but flexibility to use higher accuracy parts would be good. As this is for an internal application, I'm not sure how much else I can disclose. Thanks Dave > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From magnus at rubidium.dyndns.org Wed Jun 17 01:28:23 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 03:28:23 +0200 Subject: [time-nuts] test mailing from a new member In-Reply-To: References: <20090616083250.21347BCEF@ip-64-139-1-69.sjc.megapath.net> <4A3817B5.5010908@rubidium.dyndns.org> Message-ID: <4A3846B7.50307@rubidium.dyndns.org> David Bengtson skrev: > On Tue, Jun 16, 2009 at 6:07 PM, Magnus > Danielson wrote: >> Hal Murray skrev: >>> david.bengtson at gmail.com said: >>>> I've recently gotten an opportunity to work on a GPSDO at work, and >>>> so I now have a real need to pick up some more information on the >>>> design tradeoffs and approaches in a GPSDO. I've plowed through a pile >>>> of old emails, but it's difficult to get a good overview from email >>>> threads. >>>> I would appreciate links to discussions on the tradeoffs inherent in a >>>> GPSDO. Sampling clock rate, filter bandwidths, jitter requirements >>> Be sure you know about hanging bridges. Start with the >>> "Timing for VLBI" slides at http://gpstime.com/ >> The key issue is, what type of specs is needed? What may it cost? >> What kind of receiver may be considered? What's the intended application? >> > Specs.. Hmmmm. Good question. The application is for a frequency > reference, so frequency stability vs. PPS accuracy is important. Cost > is perhaps less important than size. The OCXO under control is a > small, surface mount part with +/- 0.5 PPM over temp, but flexibility > to use higher accuracy parts would be good. As this is for an internal > application, I'm not sure how much else I can disclose. You should consider using a board having a 10 MHz input. Otherwise the normal route is to use the PPS pulse out of a board (adjusted by any form of offset value usually available in the bitstream) and make a TI compare to a divided down variant of the OCXO. The standard approach used by many is to use a PI-loop where the bandwidth and Q-value is set with thought. A more complex approach is to go for a Kalman filter, which has the benefit of being able to more dynamically adapt and tune it. A Kalman filter for a simple setup like this isn't particularly hard to design, even if the math may seem a bit complex at first. Don't use to few bits in the DA. There are a number of simple projects around. Check if their achieved level of performance is matching your needs. In that case you know more or less what you need to stretch for. This is a topic which can go over the deep end if you let us... so asking for the required specs is really, what do you need? What can you settle with? It gives an indication of how deep you need to go. One issue to keep in mind is what kind of hold-over performance do you need, if any. That is... how much may it deviate after how long a time without propper GPS signal. Cheers, Magnus From brice at weaponeer.com Wed Jun 17 02:18:14 2009 From: brice at weaponeer.com (brice at weaponeer.com) Date: Wed, 17 Jun 2009 02:18:14 +0000 Subject: [time-nuts] Vectron OXCO test. Message-ID: Thanks for the info Bob, It does work. I just got my TM5006 travel test bench/ Tek TAS scope, Are we sure that is 12v? I will check by case type but behaves as the voltage is possibly too high. Only 15.2 mA draw at 12.000v very clean waveform, good gain. I have not modulated it yet. Working on stabilization. Maybe I am just being silly due to lack of sleep. Really cool toy, 100 mhz is correct, but pretty far off. I do not think it is a reject. but is possible. Thanks again. E1 = +12VDC, 25 mA max E2 = circuit ground E3 = modulation input, 0-10VDC, .4kHz/V to 1.2kHz/V, negative transfer E4 = case ground 100 MHz, +13 dBm output 40 ppm max, -18C to 75C --------------------------------------------------------------------- On Mon, Jun 8, 2009 at 1:30 AM, wrote: Vectron OXCO 233-5368-1 / WJ 708249-001 2.0" / 2.0" / 0.50" SMA output / mil spec, Al sheet surface mount, 4 mounting studs E1 orange / E2 black / E3 white / E4 (case ground) Probably FSN 5955-01-144-2344 Alt part # may be V26G893 . May be 100MHZ Can possibly get several more, new. Limited test equipment here, found conflicting data on part #'s. All needed is voltages or pinouts. Sounds silly, do not want to guess. Thanks, Bill William Rice Round Rock, Texas. From david.bengtson at gmail.com Wed Jun 17 03:45:05 2009 From: david.bengtson at gmail.com (David Bengtson) Date: Tue, 16 Jun 2009 23:45:05 -0400 Subject: [time-nuts] test mailing from a new member In-Reply-To: <4A3846B7.50307@rubidium.dyndns.org> References: <20090616083250.21347BCEF@ip-64-139-1-69.sjc.megapath.net> <4A3817B5.5010908@rubidium.dyndns.org> <4A3846B7.50307@rubidium.dyndns.org> Message-ID: On Tue, Jun 16, 2009 at 9:28 PM, Magnus Danielson wrote: > David Bengtson skrev: >> >> On Tue, Jun 16, 2009 at 6:07 PM, Magnus >> Danielson wrote: >>> >>> Hal Murray skrev: >>>> >>>> david.bengtson at gmail.com said: >>>>> >>>>> ?I've recently gotten an opportunity to work on a GPSDO at work, and >>>>> so I now have a real need to pick up some more information on the >>>>> design tradeoffs and approaches in a GPSDO. I've plowed through a pile >>>>> of old emails, but it's difficult to get a good overview from email >>>>> threads. >>>>> I would appreciate links to discussions on the tradeoffs inherent in a >>>>> GPSDO. Sampling clock rate, filter bandwidths, jitter requirements >>>> >>>> Be sure you know about hanging bridges. ?Start with the >>>> ?"Timing for VLBI" slides at http://gpstime.com/ >>> >>> The key issue is, what type of specs is needed? What may it cost? >>> What kind of receiver may be considered? What's the intended application? >>> >> Specs.. Hmmmm. Good question. The application is for a frequency >> reference, so frequency stability vs. PPS accuracy is important. Cost >> is perhaps less important than size. The OCXO under control is a >> small, surface mount part with +/- 0.5 PPM over temp, but flexibility >> to use higher accuracy parts would be good. As this is for an internal >> application, I'm not sure how much else I can disclose. > > You should consider using a board having a 10 MHz input. Otherwise the > normal route is to use the PPS pulse out of a board (adjusted by any form of > offset value usually available in the bitstream) and make a TI compare to a > divided down variant of the OCXO. The standard approach used by many is to > use a PI-loop where the bandwidth and Q-value is set with thought. A more > complex approach is to go for a Kalman filter, which has the benefit of > being able to more dynamically adapt and tune it. A Kalman filter for a > simple setup like this isn't particularly hard to design, even if the math > may seem a bit complex at first. > We have an on-board 10 MHz Oscillator, although that frequency may change in the future, along with a digital PLL and an off the shelf GPS receiver. We have a GPSDO that works, but there are some corner cases where it doesn't seem to work as expected, so debugging is part of what I'm going to do. > Don't use to few bits in the DA. > > There are a number of simple projects around. Check if their achieved level > of performance is matching your needs. In that case you know more or less > what you need to stretch for. Good suggestion. > > This is a topic which can go over the deep end if you let us... so asking > for the required specs is really, what do you need? What can you settle > with? It gives an indication of how deep you need to go. > Still working on this. > One issue to keep in mind is what kind of hold-over performance do you need, > if any. That is... how much may it deviate after how long a time without > propper GPS signa Hold over and re-acquision time is an issue, something I'm trying to quantify. Part of the issue I'm running into is a simple unfamiliarity with the system. Receivers, Transmitters, synthesizers, I know those well, and when I have questions, I know where to to find the answers. With a GPSDO, I'm still learning the terminology and the performance requirements, so I'm not there yet. Regards Dave > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From tvb at LeapSecond.com Wed Jun 17 07:39:56 2009 From: tvb at LeapSecond.com (Tom Van Baak) Date: Wed, 17 Jun 2009 00:39:56 -0700 Subject: [time-nuts] Ashtech Z12 vs. Z12T References: <4A383B36.9040400@rubidium.dyndns.org> Message-ID: > Not being able to compare I just ask the questions openly. Anybody has a > Z12T to lend me for a peak inside? Magnus, Yes, contact me off-line. /tvb From df6jb at ulrich-bangert.de Wed Jun 17 08:06:00 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 17 Jun 2009 10:06:00 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up Message-ID: <7D42B9B43B6E4327AD0375ABF54BDE7D@athlon> Gents, yesterday I received the Z3805 that I had bought from fluke.I on eBay and immediately put it to work. I recorded the EFC value as well as the PPS TI value over about 20 hours. Attached is the graph of thes two values. I interprete this graph in this way: 1) Immediately after power up (perhaps up to the end of the site survey) the regulation loop seems to work with a very short time constant which is able to bring the PPS TI close to zero although the OCXO has lots of drift at this time. 2) Then the loop time constant seems to switch to a significant higher value which does not keep up with the oscillator's drift, which leads to the negative excursion of nearly 500 ns. 3) This seems to be too much for the regulation which leads to switching back to the short time constant and to bring the PPS TI back to near zero and to return to the longer time constant again... 4) ...which lets the procedure repeat again and again: Drift to -500 ns and pullback. 5) Note that I thought it was a kind of malfunction and send a :system:preset command to the device after the last negative PPS TI spike. The result was, that the total procedure repeated: About 2 hours of PPS TI close to zero then again the drift and pullback procedure however with a reduced drift rate. 6) After 11 hours or so the regulation loop's time constant seems to match the OCXO's drift and a "real" lock of the pll seems to take place. (The lock led had been on already hours ago...) Since I do not have an manual for the Z3805: Can any of you Z3801 owners second this behaviour to be normal or would you think that it is kind of special for the Z3805 or even a real malfunction (in the sense that the OCXO's drift is above the specs in the beginning)? Best regards Ulrich Bangert Ulrich Bangert www.ulrich-bangert.de Ortholzer Weg 1 27243 Gross Ippener -------------- next part -------------- A non-text attachment was scrubbed... Name: Z3805.pdf Type: application/pdf Size: 11215 bytes Desc: not available URL: From jmiles at pop.net Wed Jun 17 08:25:12 2009 From: jmiles at pop.net (John Miles) Date: Wed, 17 Jun 2009 01:25:12 -0700 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <7D42B9B43B6E4327AD0375ABF54BDE7D@athlon> Message-ID: > Since I do not have an manual for the Z3805: Can any of you Z3801 owners > second this behaviour to be normal or would you think that it is kind of > special for the Z3805 or even a real malfunction (in the sense that the > OCXO's drift is above the specs in the beginning)? Any OCXO that has been sitting around for years is likely to undergo rapid aging when you first bring it up. It will be so far out of spec that I wouldn't even bother looking at the loop behavior until it's been running for a week or two. Chances are it'll be fine by then. -- john, KE5FX From df6jb at ulrich-bangert.de Wed Jun 17 08:52:06 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 17 Jun 2009 10:52:06 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: Message-ID: <821B0970EFC14531B8BD7E0ACF5E8AF6@athlon> John, > Any OCXO that has been sitting around for years is likely to > undergo rapid aging when you first bring it up. Sure! I had better formulated my question like: A constructor of a GPSDO knows, that any OCXO that has been sitting around for years is likely to undergo rapid aging when it is first brouht up. When Symmetricon choosed to switch to a long time constant early after power up, were they perhaps expecting a lower OCXO drift than I am observing now? 73s Ulrich DF6JB > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von John Miles > Gesendet: Mittwoch, 17. Juni 2009 10:25 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > > > Since I do not have an manual for the Z3805: Can any of you Z3801 > > owners second this behaviour to be normal or would you > think that it > > is kind of special for the Z3805 or even a real malfunction (in the > > sense that the OCXO's drift is above the specs in the beginning)? > > Any OCXO that has been sitting around for years is likely to > undergo rapid aging when you first bring it up. It will be > so far out of spec that I wouldn't even bother looking at the > loop behavior until it's been running for a week or two. > Chances are it'll be fine by then. > > -- john, KE5FX > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From sar10538 at gmail.com Wed Jun 17 09:03:11 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Wed, 17 Jun 2009 21:03:11 +1200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <7D42B9B43B6E4327AD0375ABF54BDE7D@athlon> References: <7D42B9B43B6E4327AD0375ABF54BDE7D@athlon> Message-ID: <1231b6a80906170203x40f9a852u6b90c904ae3b68cf@mail.gmail.com> Ulrich, What are you using to produce the graph you attached please? 73, Steve 2009/6/17 Ulrich Bangert : > Gents, > > yesterday I received the Z3805 that I had bought from fluke.I on eBay and > immediately put it to work. I recorded the EFC value as well as the PPS TI > value over about 20 hours. Attached is the graph of thes two values. > > I interprete this graph in this way: > > 1) Immediately after power up (perhaps up to the end of the site survey) the > regulation loop seems to work with a very short time constant which is able > to bring the PPS TI close to zero although the OCXO has lots of drift at > this time. > > 2) Then the loop time constant seems to switch to a significant higher value > which does not keep up with the oscillator's drift, which leads to the > negative excursion of nearly 500 ns. > > 3) This seems to be too much for the regulation which leads to switching > back to the short time constant and to bring the PPS TI back to near zero > and to return to the longer time constant again... > > 4) ...which lets the procedure repeat again and again: Drift to -500 ns and > pullback. > > 5) Note that I thought it was a kind of malfunction and send a > :system:preset command to the device after the last negative PPS TI spike. > The result was, that the total procedure repeated: About 2 hours of PPS TI > close to zero then again the drift and pullback procedure however with a > reduced drift rate. > > 6) After 11 hours or so the regulation loop's time constant seems to match > the OCXO's drift and a "real" lock of the pll seems to take place. (The lock > led had been on already hours ago...) > > Since I do not have an manual for the Z3805: Can any of you Z3801 owners > second this behaviour to be normal or would you think that it is kind of > special for the Z3805 or even a real malfunction (in the sense that the > OCXO's drift is above the specs in the beginning)? > > Best regards > Ulrich Bangert > > Ulrich Bangert > www.ulrich-bangert.de > Ortholzer Weg 1 > 27243 Gross Ippener > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From df6jb at ulrich-bangert.de Wed Jun 17 09:07:32 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 17 Jun 2009 11:07:32 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <1231b6a80906170203x40f9a852u6b90c904ae3b68cf@mail.gmail.com> Message-ID: <16A9D6AD2FD14D06A79AE6A6E309FCB6@athlon> Steve, my PLOTTER utility. I thought you did already try it out? 73s Ulrich, DF6JB > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Steve Rooke > Gesendet: Mittwoch, 17. Juni 2009 11:03 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > Ulrich, > > What are you using to produce the graph you attached please? > > 73, > Steve > > 2009/6/17 Ulrich Bangert : > > Gents, > > > > yesterday I received the Z3805 that I had bought from > fluke.I on eBay > > and immediately put it to work. I recorded the EFC value as well as > > the PPS TI value over about 20 hours. Attached is the graph of thes > > two values. > > > > I interprete this graph in this way: > > > > 1) Immediately after power up (perhaps up to the end of the site > > survey) the regulation loop seems to work with a very short time > > constant which is able to bring the PPS TI close to zero > although the > > OCXO has lots of drift at this time. > > > > 2) Then the loop time constant seems to switch to a > significant higher > > value which does not keep up with the oscillator's drift, > which leads > > to the negative excursion of nearly 500 ns. > > > > 3) This seems to be too much for the regulation which leads to > > switching back to the short time constant and to bring the > PPS TI back > > to near zero and to return to the longer time constant again... > > > > 4) ...which lets the procedure repeat again and again: > Drift to -500 > > ns and pullback. > > > > 5) Note that I thought it was a kind of malfunction and send a > > :system:preset command to the device after the last negative PPS TI > > spike. The result was, that the total procedure repeated: About 2 > > hours of PPS TI close to zero then again the drift and pullback > > procedure however with a reduced drift rate. > > > > 6) After 11 hours or so the regulation loop's time constant > seems to > > match the OCXO's drift and a "real" lock of the pll seems to take > > place. (The lock led had been on already hours ago...) > > > > Since I do not have an manual for the Z3805: Can any of you Z3801 > > owners second this behaviour to be normal or would you > think that it > > is kind of special for the Z3805 or even a real malfunction (in the > > sense that the OCXO's drift is above the specs in the beginning)? > > > > Best regards > > Ulrich Bangert > > > > Ulrich Bangert > > www.ulrich-bangert.de > > Ortholzer Weg 1 > > 27243 Gross Ippener > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > -- > Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW > A man with one clock knows what time it is; > A man with two clocks is never quite sure. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From sar10538 at gmail.com Wed Jun 17 09:28:59 2009 From: sar10538 at gmail.com (Steve Rooke) Date: Wed, 17 Jun 2009 21:28:59 +1200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <16A9D6AD2FD14D06A79AE6A6E309FCB6@athlon> References: <1231b6a80906170203x40f9a852u6b90c904ae3b68cf@mail.gmail.com> <16A9D6AD2FD14D06A79AE6A6E309FCB6@athlon> Message-ID: <1231b6a80906170228o4b84a66dl595baa697bb3df7c@mail.gmail.com> Ulrich, I must have lost the plot here but I thought that was only for HPIB data. How are you collecting the data? 73, Steve 2009/6/17 Ulrich Bangert : > Steve, > > my PLOTTER utility. I thought you did already try it out? > > 73s Ulrich, DF6JB > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Steve Rooke >> Gesendet: Mittwoch, 17. Juni 2009 11:03 >> An: Discussion of precise time and frequency measurement >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >> >> >> Ulrich, >> >> What are you using to produce the graph you attached please? >> >> 73, >> Steve >> >> 2009/6/17 Ulrich Bangert : >> > Gents, >> > >> > yesterday I received the Z3805 that I had bought from >> fluke.I on eBay >> > and immediately put it to work. I recorded the EFC value as well as >> > the PPS TI value over about 20 hours. Attached is the graph of thes >> > two values. >> > >> > I interprete this graph in this way: >> > >> > 1) Immediately after power up (perhaps up to the end of the site >> > survey) the regulation loop seems to work with a very short time >> > constant which is able to bring the PPS TI close to zero >> although the >> > OCXO has lots of drift at this time. >> > >> > 2) Then the loop time constant seems to switch to a >> significant higher >> > value which does not keep up with the oscillator's drift, >> which leads >> > to the negative excursion of nearly 500 ns. >> > >> > 3) This seems to be too much for the regulation which leads to >> > switching back to the short time constant and to bring the >> PPS TI back >> > to near zero and to return to the longer time constant again... >> > >> > 4) ...which lets the procedure repeat again and again: >> Drift to -500 >> > ns and pullback. >> > >> > 5) Note that I thought it was a kind of malfunction and send a >> > :system:preset command to the device after the last negative PPS TI >> > spike. The result was, that the total procedure repeated: About 2 >> > hours of PPS TI close to zero then again the drift and pullback >> > procedure however with a reduced drift rate. >> > >> > 6) After 11 hours or so the regulation loop's time constant >> seems to >> > match the OCXO's drift and a "real" lock of the pll seems to take >> > place. (The lock led had been on already hours ago...) >> > >> > Since I do not have an manual for the Z3805: Can any of you Z3801 >> > owners second this behaviour to be normal or would you >> think that it >> > is kind of special for the Z3805 or even a real malfunction (in the >> > sense that the OCXO's drift is above the specs in the beginning)? >> > >> > Best regards >> > Ulrich Bangert >> > >> > Ulrich Bangert >> > www.ulrich-bangert.de >> > Ortholzer Weg 1 >> > 27243 Gross Ippener >> > >> > _______________________________________________ >> > time-nuts mailing list -- time-nuts at febo.com >> > To unsubscribe, go to >> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> > and follow the instructions there. >> > >> >> >> >> -- >> Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW >> A man with one clock knows what time it is; >> A man with two clocks is never quite sure. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW A man with one clock knows what time it is; A man with two clocks is never quite sure. From bruce.griffiths at xtra.co.nz Wed Jun 17 10:39:22 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 17 Jun 2009 22:39:22 +1200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <1231b6a80906170228o4b84a66dl595baa697bb3df7c@mail.gmail.com> References: <1231b6a80906170203x40f9a852u6b90c904ae3b68cf@mail.gmail.com> <16A9D6AD2FD14D06A79AE6A6E309FCB6@athlon> <1231b6a80906170228o4b84a66dl595baa697bb3df7c@mail.gmail.com> Message-ID: <4A38C7DA.3010008@xtra.co.nz> Steve Rooke wrote: > Ulrich, > > I must have lost the plot here but I thought that was only for HPIB > data. How are you collecting the data? > > 73, > Steve > > 2009/6/17 Ulrich Bangert : > >> Steve, >> >> my PLOTTER utility. I thought you did already try it out? >> >> 73s Ulrich, DF6JB >> >> >>> -----Ursprungliche Nachricht----- >>> Von: time-nuts-bounces at febo.com >>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Steve Rooke >>> Gesendet: Mittwoch, 17. Juni 2009 11:03 >>> An: Discussion of precise time and frequency measurement >>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>> >>> >>> Ulrich, >>> >>> What are you using to produce the graph you attached please? >>> >>> 73, >>> Steve >>> >>> 2009/6/17 Ulrich Bangert : >>> >>>> Gents, >>>> >>>> yesterday I received the Z3805 that I had bought from >>>> >>> fluke.I on eBay >>> >>>> and immediately put it to work. I recorded the EFC value as well as >>>> the PPS TI value over about 20 hours. Attached is the graph of thes >>>> two values. >>>> >>>> I interprete this graph in this way: >>>> >>>> 1) Immediately after power up (perhaps up to the end of the site >>>> survey) the regulation loop seems to work with a very short time >>>> constant which is able to bring the PPS TI close to zero >>>> >>> although the >>> >>>> OCXO has lots of drift at this time. >>>> >>>> 2) Then the loop time constant seems to switch to a >>>> >>> significant higher >>> >>>> value which does not keep up with the oscillator's drift, >>>> >>> which leads >>> >>>> to the negative excursion of nearly 500 ns. >>>> >>>> 3) This seems to be too much for the regulation which leads to >>>> switching back to the short time constant and to bring the >>>> >>> PPS TI back >>> >>>> to near zero and to return to the longer time constant again... >>>> >>>> 4) ...which lets the procedure repeat again and again: >>>> >>> Drift to -500 >>> >>>> ns and pullback. >>>> >>>> 5) Note that I thought it was a kind of malfunction and send a >>>> :system:preset command to the device after the last negative PPS TI >>>> spike. The result was, that the total procedure repeated: About 2 >>>> hours of PPS TI close to zero then again the drift and pullback >>>> procedure however with a reduced drift rate. >>>> >>>> 6) After 11 hours or so the regulation loop's time constant >>>> >>> seems to >>> >>>> match the OCXO's drift and a "real" lock of the pll seems to take >>>> place. (The lock led had been on already hours ago...) >>>> >>>> Since I do not have an manual for the Z3805: Can any of you Z3801 >>>> owners second this behaviour to be normal or would you >>>> >>> think that it >>> >>>> is kind of special for the Z3805 or even a real malfunction (in the >>>> sense that the OCXO's drift is above the specs in the beginning)? >>>> >>>> Best regards >>>> Ulrich Bangert >>>> >>>> Ulrich Bangert >>>> www.ulrich-bangert.de >>>> Ortholzer Weg 1 >>>> 27243 Gross Ippener >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts at febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>> >>> -- >>> Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW >>> A man with one clock knows what time it is; >>> A man with two clocks is never quite sure. >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > > Steve You're confusing Ulrich's PLOTTER program with his EZGPIB program (which can also communicate with RS232 devices like GPSDOs). Once the data has been logged using EZGPIB, then Plotter can be used to plot/analyse the stored results. Bruce From df6jb at ulrich-bangert.de Wed Jun 17 11:33:19 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 17 Jun 2009 13:33:19 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <1231b6a80906170228o4b84a66dl595baa697bb3df7c@mail.gmail.com> Message-ID: Steve, > I must have lost the plot here but I thought that was only > for HPIB data. By far not! PLOTTER does a lot to everything than can be pressed into ASCII data column files. > How are you collecting the data? That has been done with a quick and dirty script for my EZGPIB utility (which handles serial communication and some other goodies as well). I have just included this script as "Z3805.488" to the examples. Don't accuse me that I did not have warned you: PLOTTER is written in the P-language while EZGPIB (which is written in the P-language itself) executes scripts in the P-language, P-square if you like. Better get on rubber gloves before you touch anything of it, hi. 73s Ulrich, DF6JB > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Steve Rooke > Gesendet: Mittwoch, 17. Juni 2009 11:29 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > Ulrich, > > I must have lost the plot here but I thought that was only > for HPIB data. How are you collecting the data? > > 73, > Steve > > 2009/6/17 Ulrich Bangert : > > Steve, > > > > my PLOTTER utility. I thought you did already try it out? > > > > 73s Ulrich, DF6JB > > > >> -----Ursprungliche Nachricht----- > >> Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] > >> Im Auftrag von Steve Rooke > >> Gesendet: Mittwoch, 17. Juni 2009 11:03 > >> An: Discussion of precise time and frequency measurement > >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > >> > >> > >> Ulrich, > >> > >> What are you using to produce the graph you attached please? > >> > >> 73, > >> Steve > >> > >> 2009/6/17 Ulrich Bangert : > >> > Gents, > >> > > >> > yesterday I received the Z3805 that I had bought from > >> fluke.I on eBay > >> > and immediately put it to work. I recorded the EFC value > as well as > >> > the PPS TI value over about 20 hours. Attached is the > graph of thes > >> > two values. > >> > > >> > I interprete this graph in this way: > >> > > >> > 1) Immediately after power up (perhaps up to the end of the site > >> > survey) the regulation loop seems to work with a very short time > >> > constant which is able to bring the PPS TI close to zero > >> although the > >> > OCXO has lots of drift at this time. > >> > > >> > 2) Then the loop time constant seems to switch to a > >> significant higher > >> > value which does not keep up with the oscillator's drift, > >> which leads > >> > to the negative excursion of nearly 500 ns. > >> > > >> > 3) This seems to be too much for the regulation which leads to > >> > switching back to the short time constant and to bring the > >> PPS TI back > >> > to near zero and to return to the longer time constant again... > >> > > >> > 4) ...which lets the procedure repeat again and again: > >> Drift to -500 > >> > ns and pullback. > >> > > >> > 5) Note that I thought it was a kind of malfunction and send a > >> > :system:preset command to the device after the last > negative PPS TI > >> > spike. The result was, that the total procedure > repeated: About 2 > >> > hours of PPS TI close to zero then again the drift and pullback > >> > procedure however with a reduced drift rate. > >> > > >> > 6) After 11 hours or so the regulation loop's time constant > >> seems to > >> > match the OCXO's drift and a "real" lock of the pll > seems to take > >> > place. (The lock led had been on already hours ago...) > >> > > >> > Since I do not have an manual for the Z3805: Can any of > you Z3801 > >> > owners second this behaviour to be normal or would you > >> think that it > >> > is kind of special for the Z3805 or even a real > malfunction (in the > >> > sense that the OCXO's drift is above the specs in the beginning)? > >> > > >> > Best regards > >> > Ulrich Bangert > >> > > >> > Ulrich Bangert > >> > www.ulrich-bangert.de > >> > Ortholzer Weg 1 > >> > 27243 Gross Ippener > >> > > >> > _______________________________________________ > >> > time-nuts mailing list -- time-nuts at febo.com > >> > To unsubscribe, go to > >> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> > and follow the instructions there. > >> > > >> > >> > >> > >> -- > >> Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW > >> A man with one clock knows what time it is; > >> A man with two clocks is never quite sure. > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts at febo.com > >> To unsubscribe, go to > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > -- > Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW > A man with one clock knows what time it is; > A man with two clocks is never quite sure. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From kilodelta4foxmike at gmail.com Wed Jun 17 14:57:50 2009 From: kilodelta4foxmike at gmail.com (Brian Kirby) Date: Wed, 17 Jun 2009 09:57:50 -0500 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: References: Message-ID: <4A39046E.2080407@gmail.com> Ulrich, I have two Z3801A and both of them act close to what you describe in the first 24 hours of power up. I believe its part of the disciplining algorithm. From what I read about the smart clock, it takes 5 days for it to complete its initial learning cycle and then its continuously refining. Brian From hmurray at megapathdsl.net Wed Jun 17 16:33:39 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 17 Jun 2009 09:33:39 -0700 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: Message from "Ulrich Bangert" of "Wed, 17 Jun 2009 10:52:06 +0200." <821B0970EFC14531B8BD7E0ACF5E8AF6@athlon> Message-ID: <20090617163340.6FEF3BCEF@ip-64-139-1-69.sjc.megapath.net> > Sure! I had better formulated my question like: A constructor of a > GPSDO knows, that any OCXO that has been sitting around for years is > likely to undergo rapid aging when it is first brouht up. When > Symmetricon choosed to switch to a long time constant early after > power up, were they perhaps expecting a lower OCXO drift than I am > observing now? Does anybody have any data on the startup transients for a good crystal that's been off for a year compared to one that's been off for a week or a day? My guess is that the designers ignored the off-for-a-long-time problem. It's too hard to test and doesn't happen often enough to be important. Do people who run lots of GPSDOs (telcos) store their spares powered up in order to avoid this problem? If I have 2 units, primary and secondary, and the primary dies, will the pick-one software stick with old unit for a while after the dead one is replaced even though the "primary" is now working? -- These are my opinions, not necessarily my employer's. I hate spam. From df6jb at ulrich-bangert.de Wed Jun 17 17:44:42 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 17 Jun 2009 19:44:42 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <4A39046E.2080407@gmail.com> Message-ID: <06673C88A53A4F988A051BC37AFAF35F@athlon> Brian, thanks for your information! > algorithm. From what I read about the smart clock, it takes > 5 days for it to complete its initial learning cycle and then its continuously > refining. Is that from the Z3801 manual, which I have available, or do you have any other in depth information source? Best regards Ulrich > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby > Gesendet: Mittwoch, 17. Juni 2009 16:58 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > Ulrich, > > I have two Z3801A and both of them act close to what you > describe in the > first 24 hours of power up. I believe its part of the disciplining > algorithm. From what I read about the smart clock, it takes > 5 days for > it to complete its initial learning cycle and then its continuously > refining. > > Brian > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From cdelect at juno.com Wed Jun 17 18:38:57 2009 From: cdelect at juno.com (Corby Dawson) Date: Wed, 17 Jun 2009 11:38:57 -0700 Subject: [time-nuts] DMTD question Message-ID: <20090617.113857.4016.0.cdelect@juno.com> Hi! I have been running a bunch of oscillator plots using a DMTD unit built for the NBS in the early 80s that I picked up last year and repaired. I am using an offset oscillator with a 1Hz offset (an FTS1200) for the L.O. and select the 1Hz BW on the unit. I have fed both inputs from the following oscillators thru a power splitter to evaluate the baseline. The Allen Deviation at 1 second for three different oscillators driving both inputs at the same levels and having the delay set to the same small value are. Delay 100us Osc 1 - 1.05E-13th Osc 2 - 9.50E-14th Osc 3 - 2.00E-13th At larger delay values the Allen Deviation at 1 second for Osc 3 rises much faster than the other two. Delay 100ms Osc 1 - 3.10E-13th Osc 2 - 3.50E-13th Osc 3 - 3.00E-12th Can I deduce any useful information from these numbers? Obvoisly Osc 3 is not as good as the other two at the 1 second tau! Plots run against other oscillators also show that Osc 3 causes a rise in the value at 1 second. Thanks, Corby Dawson ____________________________________________________________ Click now for low quotes on great group health insurance plans! http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTQb2SOvEObOFBY7GX9x4Nzi53TOHS8B236icJn2YVVYm4qAqfZrSQ/ From magnus at rubidium.dyndns.org Wed Jun 17 19:31:06 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 21:31:06 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <4A39046E.2080407@gmail.com> References: <4A39046E.2080407@gmail.com> Message-ID: <4A39447A.9080705@rubidium.dyndns.org> Hi Brian, Brian Kirby skrev: > Ulrich, > > I have two Z3801A and both of them act close to what you describe in the > first 24 hours of power up. I believe its part of the disciplining > algorithm. From what I read about the smart clock, it takes 5 days for > it to complete its initial learning cycle and then its continuously > refining. For me it sounds more like a design-flaw than anything else. Using several PLL bandwidths and switch between them is as such a good approach, but the stepping between then needs to be done such that a narrower bandwidth is only chosen when it the lock-in can be maintained. Similarly, backing out of a narrow step to a wider step should also be detected at suitable levels when it can't maintain track. The phase detector gives hints about the ability to maintain track, as the phase will deviate uncontrollably when loosing lock, but before that happens it will deviate from near +/- 0 degrees, similarly, when within near +/- 0 degrees for sufficient time it is reasnoble that the next step (if not too big) can maintain track. Recall that "sufficient time" changes with the bandwidth of the PLL. A third degree (PII^2 or PII^2D) PLL is better able to cope with drift rate than a second degree PLL. A combined phase/frequency detection approach (I.e. add the D term) adds quicker response to drift and ability to keep tracking. Another approach is to use a Kalman filter, where the Kalman gain is adapted continuously. Kalman filters takes some careful thought, it's not a magical wand to wave to make things better by magic. If done properly, it will be able to fairly well track along and detect the drift rate (takes a phase/frequency/drift model to handle) and update as it stabilizes. None of these approaches is rocket science to design anymore. HP/Agilent surely could at the time of Z3801A and followers. Cheers, Magnus From dforbes at dakotacom.net Wed Jun 17 19:50:07 2009 From: dforbes at dakotacom.net (David Forbes) Date: Wed, 17 Jun 2009 12:50:07 -0700 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <4A39447A.9080705@rubidium.dyndns.org> References: <4A39046E.2080407@gmail.com> <4A39447A.9080705@rubidium.dyndns.org> Message-ID: <4A3948EF.1020806@dakotacom.net> Magnus Danielson wrote: > > None of these approaches is rocket science to design anymore. HP/Agilent > surely could at the time of Z3801A and followers. Yet the problem of an oscillator having a high drift rate after long-term storage is not one that a development team is likely to be thinking about. Nor is it a problem that can be easily examined, since it requires a bunch of old units lying around the development lab. Old units don't exist when the product is new, and even if they had traveled back in time to buy and age a few units, after sufficient testing they would stop drifting and therefore be useless for the test. Nevertheless, 25 years later we expect the whiz-bang engineers at HP to have thought of the problem and solved it. --David Forbes, Tucson From frledda at verizon.net Wed Jun 17 19:53:43 2009 From: frledda at verizon.net (Francesco Ledda) Date: Wed, 17 Jun 2009 14:53:43 -0500 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <4A39447A.9080705@rubidium.dyndns.org> Message-ID: A third order PPL has better sideband suppression. The tracking capability depends upon the phase range of the phase detector. If 1:1 phase comparison and a XOR phase detector is used, the range is 180 degrees. Dividers on the feedback portion of the PLL increase the phase range of the phase detector. For example, if the expected jitter is 10UI, a divider larger than 10 must be used, to maintain lock under all conditions. A monotonically decreasing phase delta, on the phase detector, still means that the PLL is locked. The phase/frequency detector, avoids the need for a frequency aquisition aid. Once a phase reversal is detected by the flip flops in the phase/freq detector, it goes back to phase detector mode. My experience is that most fancy syncrhonizer for telecom application (Stratum, LORAN and GPS) use start-stop phase detector with averager in front of the AC-DC gain circuits. Changing the closed loop bandwidth of the PLL on the fly is not easy, due to secondary effects (done that many times). -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Magnus Danielson Sent: Wednesday, June 17, 2009 2:31 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Z3805 initial behaviour after power up Hi Brian, Brian Kirby skrev: > Ulrich, > > I have two Z3801A and both of them act close to what you describe in the > first 24 hours of power up. I believe its part of the disciplining > algorithm. From what I read about the smart clock, it takes 5 days for > it to complete its initial learning cycle and then its continuously > refining. For me it sounds more like a design-flaw than anything else. Using several PLL bandwidths and switch between them is as such a good approach, but the stepping between then needs to be done such that a narrower bandwidth is only chosen when it the lock-in can be maintained. Similarly, backing out of a narrow step to a wider step should also be detected at suitable levels when it can't maintain track. The phase detector gives hints about the ability to maintain track, as the phase will deviate uncontrollably when loosing lock, but before that happens it will deviate from near +/- 0 degrees, similarly, when within near +/- 0 degrees for sufficient time it is reasnoble that the next step (if not too big) can maintain track. Recall that "sufficient time" changes with the bandwidth of the PLL. A third degree (PII^2 or PII^2D) PLL is better able to cope with drift rate than a second degree PLL. A combined phase/frequency detection approach (I.e. add the D term) adds quicker response to drift and ability to keep tracking. Another approach is to use a Kalman filter, where the Kalman gain is adapted continuously. Kalman filters takes some careful thought, it's not a magical wand to wave to make things better by magic. If done properly, it will be able to fairly well track along and detect the drift rate (takes a phase/frequency/drift model to handle) and update as it stabilizes. None of these approaches is rocket science to design anymore. HP/Agilent surely could at the time of Z3801A and followers. Cheers, Magnus _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From holrum at hotmail.com Wed Jun 17 21:14:05 2009 From: holrum at hotmail.com (Mark Sims) Date: Wed, 17 Jun 2009 21:14:05 +0000 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: References: Message-ID: I have had four HP5370A counters (three with 10811 oscillators and one with the 10544). All four units took a very long time to stabilize after being in storage for who knows how long. Typically I would set the oscillators so that the freq of a 10 MHz cesium would read around 0.006 Hz high. The first week the counter would drift below 10 MHz a few times every day. The next week took them around a day. It was a good two months before the oscillators finally stabilized to the point where they would not drift by more than 0.002 Hz per month. Interestingly, the 10544 oscillator shows, by far, the best long term aging. I also have several of those surplus UCT 8663 double oven oscillators that I installed in Tek 5010 counters. They typically take a couple of weeks to age in so that the last digit is no longer drifting. Also, in frequency counters, all these oscillators drift such that the counter reading decreases. ---------------------------------------- ---------------------------------------- _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From hmurray at megapathdsl.net Wed Jun 17 21:49:43 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 17 Jun 2009 14:49:43 -0700 Subject: [time-nuts] test mailing from a new member In-Reply-To: Message from David Bengtson of "Tue, 16 Jun 2009 20:59:02 EDT." Message-ID: <20090617214944.1D5CEBCEF@ip-64-139-1-69.sjc.megapath.net> david.bengtson at gmail.com said: > Specs.. Hmmmm. Good question. The application is for a frequency > reference, so frequency stability vs. PPS accuracy is important. Cost > is perhaps less important than size. The OCXO under control is a > small, surface mount part with +/- 0.5 PPM over temp, but flexibility > to use higher accuracy parts would be good. As this is for an internal > application, I'm not sure how much else I can disclose. 0.5 ppm is pretty sloppy for an OCXO, at least relative to what this group normally talks about. The other major parameter to consider is the location of your GPS antenna. Don't forget things like snow and birds building nests. For a given quality output, there is a trade-off between the quality of the crystal and the quality of the GPS signal (antenna location and antenna/receiver sensitivity, noise rejection etc). Begin core-dump mode: GPS units come in several flavors: Navigation Timing Surveying The typical consumer GPS gear is setup for Navigation. Most of the low cost units use NMEA (National Marine Electronics Association) protocol on the serial port. Some of them have PPS signals. The Garmin 18x-LVC is popular for running NTP on a PC. Most of the newer/cheaper ones use USB which obviously doesn't support a PPS signal. They generally need to see at least 3 satellites in order to get a lock. (4 is the right number, but they fake it with 3 by pretending to be at sea-level. Maybe that's ground level, with elevation from either a map or recent history.) The timing units can get away with only 1 satellite because they know where they are located. You either tell it the location or tell it to run a survey which averages the location over many samples. Motorola used to make a line of good timing receivers, but they got out of that business and sold it to iLotus available through Synergy: http://www.synergy-gps.com/ GPS units typically come in 2 packaging styles. Some have the antenna and receiver packaged separately. Some come packaged together. Some of the antennas and packaged-together units are setup for serious outdoor mounting. The packaged-together units often use RS-422 (rather than 232) so they work with longer cable runs. You said size is important. Can you move all the GPSDO stuff outside your box? You have to bring in one cable. It might as well be 10 MHz rather than the GPS antenna feed. As a straw man, consider something like a T-Bolt. Even if you don't use it in your product, consider getting one for your lab so you will have something to compare with and/or a handy lab reference. -- These are my opinions, not necessarily my employer's. I hate spam. From magnus at rubidium.dyndns.org Wed Jun 17 21:53:32 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 17 Jun 2009 23:53:32 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <4A3948EF.1020806@dakotacom.net> References: <4A39046E.2080407@gmail.com> <4A39447A.9080705@rubidium.dyndns.org> <4A3948EF.1020806@dakotacom.net> Message-ID: <4A3965DC.7030002@rubidium.dyndns.org> David Forbes skrev: > Magnus Danielson wrote: >> >> None of these approaches is rocket science to design anymore. >> HP/Agilent surely could at the time of Z3801A and followers. > > Yet the problem of an oscillator having a high drift rate after > long-term storage is not one that a development team is likely to be > thinking about. > > Nor is it a problem that can be easily examined, since it requires a > bunch of old units lying around the development lab. Old units don't > exist when the product is new, and even if they had traveled back in > time to buy and age a few units, after sufficient testing they would > stop drifting and therefore be useless for the test. > > Nevertheless, 25 years later we expect the whiz-bang engineers at HP to > have thought of the problem and solved it. Starting any oscillator from cold is pretty upsetting and takes time to drift in. But sure, it is kind of not so probable that they would encounter it. But still, crystal oscillators is individuals and there are other forms of abuse (such as chock) that can occur in an oscillators life... so you would expect that some anticipation of a "less ideal case" might have passed their minds. Ah well, maybe that is me... I hate seeing returns from the field only due to fairly easy mistakes in the design. Not that it doesn't happens, but it's a learning process to improve on design margin. Cheers, Magnus From magnus at rubidium.dyndns.org Wed Jun 17 22:09:49 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Thu, 18 Jun 2009 00:09:49 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: References: Message-ID: <4A3969AD.6090306@rubidium.dyndns.org> Hi Francesco, Francesco Ledda skrev: > A third order PPL has better sideband suppression. The tracking capability > depends upon the phase range of the phase detector. If 1:1 phase comparison > and a XOR phase detector is used, the range is 180 degrees. Dividers on the > feedback portion of the PLL increase the phase range of the phase detector. > For example, if the expected jitter is 10UI, a divider larger than 10 must > be used, to maintain lock under all conditions. A monotonically decreasing > phase delta, on the phase detector, still means that the PLL is locked. True, but regardless of how large you have made your phase detectors range, if you have a loop unable to track to the dynamics you put into it, you eventually reach the wrapping or limiting point. By back out into quicker response, the PLL is able to quicker reduce the phase error and track it in, as it quicker adjust its state to match the difference between the source and the oscillator. > The phase/frequency detector, avoids the need for a frequency aquisition > aid. Once a phase reversal is detected by the flip flops in the phase/freq > detector, it goes back to phase detector mode. Sure, but it does not totally remove the benefits of shifting PLL bandwidth according to need. I'm all for phase/frequency detectors... and have designed several. > My experience is that most fancy syncrhonizer for telecom application > (Stratum, LORAN and GPS) use start-stop phase detector with averager in > front of the AC-DC gain circuits. Changing the closed loop bandwidth of the > PLL on the fly is not easy, due to secondary effects (done that many times). Such a detector isn't particularly useful for most GPSDOs as they get have 1 Hz comparator frequency with the PPS pulse. The analog time-constants would be a terrible mess to design. For GPSDOs using PPS updates a digital loop filter can be assumed (unless you use say the Jupiter receiver and it's 10 kHz output, see performance on TvB pages!). Being able to scale loop parameters without having to re-scale state is indeed an issue, but there exists topologies that can achieve this without the need for rescaling. These can be realized both in the analogue world using say OTAs and or through multipliers at the right positions when done in the digital world. It is used with great success in the GPS code and carrier tracking channels. You can look it up in the Kaplan GPS book for instance... which only summarize what's found in other places. Cheers, Magnus From bruce.griffiths at xtra.co.nz Wed Jun 17 22:45:37 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 18 Jun 2009 10:45:37 +1200 Subject: [time-nuts] DMTD question In-Reply-To: <20090617.113857.4016.0.cdelect@juno.com> References: <20090617.113857.4016.0.cdelect@juno.com> Message-ID: <4A397211.6090801@xtra.co.nz> Corby Dawson wrote: > Hi! > > I have been running a bunch of oscillator plots using a DMTD unit built > for the NBS in the early 80s that I picked up last year and repaired. > > I am using an offset oscillator with a 1Hz offset (an FTS1200) for the > L.O. and select the 1Hz BW on the unit. > > I have fed both inputs from the following oscillators thru a power > splitter to evaluate the baseline. > > The Allen Deviation at 1 second for three different oscillators driving > both inputs at the same levels and having the delay set to the same small > value are. > Delay 100us > Osc 1 - 1.05E-13th > Osc 2 - 9.50E-14th > Osc 3 - 2.00E-13th > > At larger delay values the Allen Deviation at 1 second for Osc 3 rises > much faster than the other two. > > Delay 100ms > Osc 1 - 3.10E-13th > Osc 2 - 3.50E-13th > Osc 3 - 3.00E-12th > > Can I deduce any useful information from these numbers? > > Obvoisly Osc 3 is not as good as the other two at the 1 second tau! > > Plots run against other oscillators also show that Osc 3 causes a rise in > the value at 1 second. > > Thanks, > > Corby Dawson > ____________________________________________________________ > Click now for low quotes on great group health insurance plans! > http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTQb2SOvEObOFBY7GX9x4Nzi53TOHS8B236icJn2YVVYm4qAqfZrSQ/ > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > Corby The noise contribution of the offset oscillator is incompletely canceled when the delay between the zero crossings for both channels isn't zero. The effect increases with the delay between zero crossings as your tests demonstrate. You can deduce little from the test apart from the fact that Osc 3 has worse performance than that of the other 2 oscillators. Bruce From magnus at rubidium.dyndns.org Wed Jun 17 23:11:50 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Thu, 18 Jun 2009 01:11:50 +0200 Subject: [time-nuts] DMTD question In-Reply-To: <4A397211.6090801@xtra.co.nz> References: <20090617.113857.4016.0.cdelect@juno.com> <4A397211.6090801@xtra.co.nz> Message-ID: <4A397836.7060704@rubidium.dyndns.org> Hi Corby, > Corby > > The noise contribution of the offset oscillator is incompletely canceled > when the delay between the zero crossings for both channels isn't zero. > The effect increases with the delay between zero crossings as your tests > demonstrate. > You can deduce little from the test apart from the fact that Osc 3 has > worse performance than that of the other 2 oscillators. I agree with Bruce, the delay removes the cross-correlation gain in the suppression of the transfer oscillator. Compare the oscillators pair-wise instead. Cheers, Magnus From bruce.griffiths at xtra.co.nz Wed Jun 17 23:42:19 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 18 Jun 2009 11:42:19 +1200 Subject: [time-nuts] DMTD question In-Reply-To: <4A397836.7060704@rubidium.dyndns.org> References: <20090617.113857.4016.0.cdelect@juno.com> <4A397211.6090801@xtra.co.nz> <4A397836.7060704@rubidium.dyndns.org> Message-ID: <4A397F5B.30008@xtra.co.nz> Magnus Danielson wrote: > Hi Corby, > >> Corby >> >> The noise contribution of the offset oscillator is incompletely canceled >> when the delay between the zero crossings for both channels isn't zero. >> The effect increases with the delay between zero crossings as your tests >> demonstrate. >> You can deduce little from the test apart from the fact that Osc 3 has >> worse performance than that of the other 2 oscillators. > > I agree with Bruce, the delay removes the cross-correlation gain in > the suppression of the transfer oscillator. Compare the oscillators > pair-wise instead. > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Another question that arises is the stability/jitter of the 100ms delay itself. How was this 100ms delay achieved? Bruce From kilodelta4foxmike at gmail.com Wed Jun 17 23:50:46 2009 From: kilodelta4foxmike at gmail.com (Brian Kirby) Date: Wed, 17 Jun 2009 18:50:46 -0500 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <06673C88A53A4F988A051BC37AFAF35F@athlon> References: <06673C88A53A4F988A051BC37AFAF35F@athlon> Message-ID: <4A398156.6050704@gmail.com> They do not talk about driving the frequency off, but they warn to keep the receiver locked the first 24 hours, so it can determine how the oscillator ages. Its in the section on "holdover" (page 52 of the PDF , page 3-8 of the user guide). You may also want to search for HP An1279, it also goes over HP smartclock operation, and look for a paper titled "the Global Positioning System and HP SmartClock" by John A. Kusters. If you have a broadband connection, I can email you each one, if that will help. Brian Ulrich Bangert wrote: > Brian, > > thanks for your information! > > >> algorithm. From what I read about the smart clock, it takes >> 5 days for it to complete its initial learning cycle and then its >> > continuously > >> refining. >> > > Is that from the Z3801 manual, which I have available, or do you have any > other in depth information source? > > Best regards > Ulrich > > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby >> Gesendet: Mittwoch, 17. Juni 2009 16:58 >> An: Discussion of precise time and frequency measurement >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >> >> >> Ulrich, >> >> I have two Z3801A and both of them act close to what you >> describe in the >> first 24 hours of power up. I believe its part of the disciplining >> algorithm. From what I read about the smart clock, it takes >> 5 days for >> it to complete its initial learning cycle and then its continuously >> refining. >> >> Brian >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From magnus at rubidium.dyndns.org Thu Jun 18 00:21:00 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Thu, 18 Jun 2009 02:21:00 +0200 Subject: [time-nuts] DMTD question In-Reply-To: <4A397F5B.30008@xtra.co.nz> References: <20090617.113857.4016.0.cdelect@juno.com> <4A397211.6090801@xtra.co.nz> <4A397836.7060704@rubidium.dyndns.org> <4A397F5B.30008@xtra.co.nz> Message-ID: <4A39886C.1050302@rubidium.dyndns.org> Bruce Griffiths skrev: > Magnus Danielson wrote: >> Hi Corby, >> >>> Corby >>> >>> The noise contribution of the offset oscillator is incompletely canceled >>> when the delay between the zero crossings for both channels isn't zero. >>> The effect increases with the delay between zero crossings as your tests >>> demonstrate. >>> You can deduce little from the test apart from the fact that Osc 3 has >>> worse performance than that of the other 2 oscillators. >> I agree with Bruce, the delay removes the cross-correlation gain in >> the suppression of the transfer oscillator. Compare the oscillators >> pair-wise instead. >> >> Cheers, >> Magnus >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > Another question that arises is the stability/jitter of the 100ms delay > itself. > How was this 100ms delay achieved? Indeed. The NBS DMTD system I know of doesn't have this feature. Cheers, Magnus From bruce.griffiths at xtra.co.nz Thu Jun 18 01:19:58 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 18 Jun 2009 13:19:58 +1200 Subject: [time-nuts] DMTD question In-Reply-To: <4A39886C.1050302@rubidium.dyndns.org> References: <20090617.113857.4016.0.cdelect@juno.com> <4A397211.6090801@xtra.co.nz> <4A397836.7060704@rubidium.dyndns.org> <4A397F5B.30008@xtra.co.nz> <4A39886C.1050302@rubidium.dyndns.org> Message-ID: <4A39963E.2060302@xtra.co.nz> Magnus Danielson wrote: > Bruce Griffiths skrev: >> Magnus Danielson wrote: >>> Hi Corby, >>> >>>> Corby >>>> >>>> The noise contribution of the offset oscillator is incompletely >>>> canceled >>>> when the delay between the zero crossings for both channels isn't >>>> zero. >>>> The effect increases with the delay between zero crossings as your >>>> tests >>>> demonstrate. >>>> You can deduce little from the test apart from the fact that Osc 3 has >>>> worse performance than that of the other 2 oscillators. >>> I agree with Bruce, the delay removes the cross-correlation gain in >>> the suppression of the transfer oscillator. Compare the oscillators >>> pair-wise instead. >>> >>> Cheers, >>> Magnus >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> Another question that arises is the stability/jitter of the 100ms delay >> itself. >> How was this 100ms delay achieved? > > Indeed. The NBS DMTD system I know of doesn't have this feature. > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Hej Magnus This could be done by changing the phase difference between the 2 inputs to the 2 channels by 10% of the mixer input signal period or by about 20ns at 5MHz. Even so questioning the stability of this delay is reasonable considering that an instability of 0.3ps or so would be equivalent to the observed noise at 100ms delay between the zerocrossings of the 2 mixer outputs. A temperature fluctuation of 1C would produce a 2ps change in phase shift if ordinary coax were used for the delay. Bruce From df6jb at ulrich-bangert.de Thu Jun 18 06:28:38 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 18 Jun 2009 08:28:38 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up In-Reply-To: <4A398156.6050704@gmail.com> Message-ID: <9368E155E80C4D3CA0FB7EB6977594C6@athlon> Brian, > You may also want to search for HP An1279, it also goes over HP > smartclock operation, and look for a paper titled "the Global > Positioning System and HP SmartClock" by John A. Kusters. In the meantime I have not only found these but also "Smart Clock: A New Time" by David Allan et al which shows that "Smart Clock" is originally a NIST invention & patent and explains very well how it works. Perhaps what I and You have seen is a direct consequence of applying the Smart Clock algorithm. Best regards Ulrich > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby > Gesendet: Donnerstag, 18. Juni 2009 01:51 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > They do not talk about driving the frequency off, but they > warn to keep > the receiver locked the first 24 hours, so it can determine how the > oscillator ages. Its in the section on "holdover" (page 52 > of the PDF , > page 3-8 of the user guide). > > You may also want to search for HP An1279, it also goes over HP > smartclock operation, and look for a paper titled "the Global > Positioning System and HP SmartClock" by John A. Kusters. > > If you have a broadband connection, I can email you each one, if that > will help. > > Brian > > Ulrich Bangert wrote: > > Brian, > > > > thanks for your information! > > > > > >> algorithm. From what I read about the smart clock, it takes > >> 5 days for it to complete its initial learning cycle and then its > >> > > continuously > > > >> refining. > >> > > > > Is that from the Z3801 manual, which I have available, or > do you have > > any other in depth information source? > > > > Best regards > > Ulrich > > > > > >> -----Ursprungliche Nachricht----- > >> Von: time-nuts-bounces at febo.com > >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby > >> Gesendet: Mittwoch, 17. Juni 2009 16:58 > >> An: Discussion of precise time and frequency measurement > >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > >> > >> > >> Ulrich, > >> > >> I have two Z3801A and both of them act close to what you > >> describe in the > >> first 24 hours of power up. I believe its part of the > disciplining > >> algorithm. From what I read about the smart clock, it takes > >> 5 days for > >> it to complete its initial learning cycle and then its > continuously > >> refining. > >> > >> Brian > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts at febo.com > >> To unsubscribe, go to > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > >> > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From df6jb at ulrich-bangert.de Thu Jun 18 08:04:01 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 18 Jun 2009 10:04:01 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up revised In-Reply-To: <9368E155E80C4D3CA0FB7EB6977594C6@athlon> Message-ID: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> Gents, one of the papers suggested by Brian says: ------------------------------------------- SmartClock monitors the frequency control variable of the internal oscillator while it is locked to the external reference. This gives a measure of the frequency difference between the internal oscillator, if it is free-running, and the external reference over time. The resulting measurements include the effects of random noise in the oscillator, the measurement circuitry, and any noise in the external reference as well as any aging and environmental effects in the oscillator. From this information, SmartClock makes a continuous prediction of clock error over time. ------------------------------------------- The big question is: If the EFC signal includes this all information, how does the algo manage to extract the individual informations? After having a look at the PPS TI and the EFC of my Z3805 I am beginning to get a clue of it (the quirks on the EFC signal heve been removed): The SmartClock algo seems to set the loop time constants to a large value in the beginning. In other words: It measures the overall oscillator frequency influencing effects with a lowpass filter applied that has a very low cutoff frequency. Only effects which's frequency are sufficient lower then the cutoff pass the filter. Seems as if the SmartClock uses this filter setting to exclude any noise related effect and any environmental effect and make the measurement see ONLY the oscillator's aging. Once it has learned enough about the aging process it will be able to predict aging. Having reached this state it will be able to apply his knowledge about aging to further TI measurements and subtract the "aging part" of it, leaving mostly the environmental (which is mostly temperature) part. Having a model for the aging the Algo can now model the temperature dependence. However, a precondition for this were that the measurement sees the temperature effects and that the ambient temperature is measured independently. For that reason I expect the Algo will reduce its loop time constant within the next time to make the temperature effect get through the lowpass. Any bets on that? Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert > Gesendet: Donnerstag, 18. Juni 2009 08:29 > An: 'Discussion of precise time and frequency measurement' > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > Brian, > > > You may also want to search for HP An1279, it also goes over HP > > smartclock operation, and look for a paper titled "the Global > > Positioning System and HP SmartClock" by John A. Kusters. > > In the meantime I have not only found these but also "Smart > Clock: A New Time" by David Allan et al which shows that > "Smart Clock" is originally a NIST invention & patent and > explains very well how it works. Perhaps what I and You have > seen is a direct consequence of applying the Smart Clock algorithm. > > Best regards > Ulrich > > > > -----Ursprungliche Nachricht----- > > Von: time-nuts-bounces at febo.com > > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby > > Gesendet: Donnerstag, 18. Juni 2009 01:51 > > An: Discussion of precise time and frequency measurement > > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > > > > They do not talk about driving the frequency off, but they > > warn to keep > > the receiver locked the first 24 hours, so it can determine how the > > oscillator ages. Its in the section on "holdover" (page 52 > > of the PDF , > > page 3-8 of the user guide). > > > > You may also want to search for HP An1279, it also goes over HP > > smartclock operation, and look for a paper titled "the Global > > Positioning System and HP SmartClock" by John A. Kusters. > > > > If you have a broadband connection, I can email you each > one, if that > > will help. > > > > Brian > > > > Ulrich Bangert wrote: > > > Brian, > > > > > > thanks for your information! > > > > > > > > >> algorithm. From what I read about the smart clock, it > takes 5 days > > >> for it to complete its initial learning cycle and then its > > >> > > > continuously > > > > > >> refining. > > >> > > > > > > Is that from the Z3801 manual, which I have available, or > > do you have > > > any other in depth information source? > > > > > > Best regards > > > Ulrich > > > > > > > > >> -----Ursprungliche Nachricht----- > > >> Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] > > >> Im Auftrag von Brian Kirby > > >> Gesendet: Mittwoch, 17. Juni 2009 16:58 > > >> An: Discussion of precise time and frequency measurement > > >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > >> > > >> > > >> Ulrich, > > >> > > >> I have two Z3801A and both of them act close to what you > describe > > >> in the first 24 hours of power up. I believe its part of the > > disciplining > > >> algorithm. From what I read about the smart clock, it takes > > >> 5 days for > > >> it to complete its initial learning cycle and then its > > continuously > > >> refining. > > >> > > >> Brian > > >> > > >> _______________________________________________ > > >> time-nuts mailing list -- time-nuts at febo.com > > >> To unsubscribe, go to > > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > >> and follow the instructions there. > > >> > > > > > > > > > _______________________________________________ > > > time-nuts mailing list -- time-nuts at febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. -------------- next part -------------- A non-text attachment was scrubbed... Name: Z3805.pdf Type: application/pdf Size: 15616 bytes Desc: not available URL: From namichie at gmail.com Thu Jun 18 11:00:28 2009 From: namichie at gmail.com (Neville Michie) Date: Thu, 18 Jun 2009 21:00:28 +1000 Subject: [time-nuts] TBOLT learning Message-ID: Hi, I am building a temperature control system to keep a tbolt warm. If I start it at a constant temperature which never varies how can it learn what its temperature coefficient is? Should it be started in varying ambient conditions for a day or a week to learn then control the temperature? Should it be run at 5 degrees below control then 5 degrees above to teach it? Does anybody know? could be an interesting project, cheers, Neville Michie From bruce.griffiths at xtra.co.nz Thu Jun 18 12:09:57 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 19 Jun 2009 00:09:57 +1200 Subject: [time-nuts] TBOLT learning In-Reply-To: References: Message-ID: <4A3A2E95.2040501@xtra.co.nz> Neville Michie wrote: > Hi, > I am building a temperature control system to keep a tbolt warm. > If I start it at a constant temperature which never varies how can it > learn > what its temperature coefficient is? > Should it be started in varying ambient conditions for a day or a week > to learn > then control the temperature? > Should it be run at 5 degrees below control then 5 degrees above to > teach it? > Does anybody know? > could be an interesting project, > cheers, Neville Michie > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Neville Given the finite resolution of the temperature sensor if the temperature variation within the chamber is less than this it wont won't matter. Since the temperature coefficient may not be constant its probably advisable to have the temperature vary smoothly over a range rather than just choosing 2 temperatures. The tbolt software is probably designed to cope with smooth temperature variations. The tbolt may not actually retain the temperature corrections for more than a few days at most as it continually adapts to its surroundings so allowing it to learn its tempco may not be very useful if you intend to closely regulate the temperature of its surroundings. Bruce From df6jb at ulrich-bangert.de Thu Jun 18 13:50:43 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 18 Jun 2009 15:50:43 +0200 Subject: [time-nuts] TBOLT learning In-Reply-To: <4A3A2E95.2040501@xtra.co.nz> Message-ID: <392509D47BC347729D1EACE5943386A9@athlon> Bruce and Neville, IF the Tbolt can learn something at all, it must be a completely different process against the Z3801 with the TBolt's loop time constant being fixed by the user (or by 100 s as the default). Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Bruce Griffiths > Gesendet: Donnerstag, 18. Juni 2009 14:10 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] TBOLT learning > > > Neville Michie wrote: > > Hi, > > I am building a temperature control system to keep a tbolt > warm. If I > > start it at a constant temperature which never varies how > can it learn > > what its temperature coefficient is? > > Should it be started in varying ambient conditions for a > day or a week > > to learn > > then control the temperature? > > Should it be run at 5 degrees below control then 5 degrees above to > > teach it? > > Does anybody know? > > could be an interesting project, > > cheers, Neville Michie > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > Neville > > Given the finite resolution of the temperature sensor if the > temperature variation within the chamber is less than this it > wont won't matter. > > Since the temperature coefficient may not be constant its > probably advisable to have the temperature vary smoothly over > a range rather than just choosing 2 temperatures. The tbolt > software is probably designed to cope with smooth temperature > variations. > > The tbolt may not actually retain the temperature corrections > for more than a few days at most as it continually adapts to > its surroundings so allowing it to learn its tempco may not > be very useful if you intend to closely regulate the > temperature of its surroundings. > > Bruce > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From xde-l2g3 at myamail.com Thu Jun 18 13:41:06 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Thu, 18 Jun 2009 10:41:06 -0300 Subject: [time-nuts] Satellite Glitch Rekindles GPS Concerns Message-ID: An article in NetWork World discusses performance degredation in the new Lockheed-built GPS IIR-2 satellite. Apparently. the new L5 transmissions are interfering with other signals from the satellite. This reduces the accuracy an order of magnitude, from 2 feet to 20 feet. It should have a corresponding effect on the accuracy of the decoded time signals. The Air Force said it has identified several parameters in the GPS IIR-20 (M)'s navigation message that can be corrected and is studying the impact these may have on military and civil GPS users. Presumably, the problem will be corrected in the 12 Boeing GPS satellites currently being built that also feature the L5 signal. The article discusses issues such as delays due to techical problems, cost overruns, and aging of the fleet. These could affect system performance in the future. However, Col. Dave Buckman stated "The issue is under control. We are working hard to get out the word. The issue is not whether GPS will stop working. There's only a small risk we will not continue to exceed our performance standard," he said. http://www.networkworld.com/community/node/42767 From brooke at pacific.net Thu Jun 18 16:55:46 2009 From: brooke at pacific.net (Brooke Clarke) Date: Thu, 18 Jun 2009 09:55:46 -0700 Subject: [time-nuts] Satellite Glitch Rekindles GPS Concerns In-Reply-To: References: Message-ID: <4A3A7192.1080606@pacific.net> Hi Mike: The current issue of Inside GNSS has two articles about this and their web page has a new article dated 17 June 2009. http://www.insidegnss.com/ Also on line is a story that directly relates to GPS: "eLoran: The Never-Ending Story?" http://www.insidegnss.com/node/1571 ------------------------- Glen Gibbons June 15, 2009 To say that enhanced Loran (eLoran) has been an on-again off-again program would give short shrift to multiple generations of official ambivalence about the proposed backup for GPS. The latest chapter began on June 4 when Senator Maria Cantwell (D-Washington) introduced S. 1194, the Coast Guard Authorization Act for Fiscal Years 2010 and 2011 (FY2010/11). Among other details, the measure directs the Secretary of Transportation to continue the Loran system until a plan has been drawn up and implemented to transition the program to eLoran. In effect, this would reverse the course set by President Obama, whose FY10 budget proposal calls for termination of Loran in the coming year. At a May 7 press conference the president described Loran as a system that?s been eclipsed by the rise of GPS. ?Year after year, this obsolete technology has continued to be funded even though it serves no government function and very few people are left who still actually use it,? Obama said. The president?s proposal had overruled plans set in motion last year for the Department of Homeland Security (DHS) to complete the upgrade to eLoran as a backup to GPS. Now, S. 1194 would authorize the appropriation of $37 million for each of fiscal years 2010 and 2011 and direct the U.S. Coast Guard (USCG) to modernize and upgrade the Loran infrastructure to provide eLoran services. Under the legislation, the Department of Transportation (DoT) could transfer funds from the Federal Aviation Administration (FAA) or other DoT agencies to reimburse the USCG for costs of the modernization. The activity comes at the same time that a Government Accountability Office (GAO) report warns about the possibility that the GPS constellation may decline substantially in the coming years. Prospects for passage of S. 1194 appear promising. Cantwell is chairwoman of the Oceans, Atmosphere, Fisheries, and Coast Guard subcommittee of the Senate Committee on Commerce, Science, and Transportation to which S. 1194 has been referred. Three senators join her as cosponsors of the measure: Sen. Olympia Snowe (R-Maine), the ranking Republican member of the subcommittee; John D. Rockefeller IV (D-West Virginia), chairman of the Commerce, Science, and Transportation Committee itself, and Kay Hutchison (R-Texas), the committee?s ranking Republican. The legislation implicitly confirms the findings of an Independent Assessment Team (IAT) on eLoran, funded by the office of the under secretary of transportation policy and chaired by Brad Parkinson, the first program manager for GPS. DoT contracted with the Institute for Defense Analysis (IDA), which organized the IAT with IDA staff member Jim Doherty serving as the IAT?s executive director. If offset by an estimated $146 million decommissioning cost of existing Loran infrastructure, the IAT concluded that eLoran could be established effectively for free. Going forward, eLoran would require only the current $37 million per year in USCG operations and management base funds for Loran plus $20 million a year in new funds for five to eight years to complete all upgrades, new transmitters, and ?jump start? deferred maintenance. After that time, savings from substantially reduced staffing at the modernized facilities would offset eLoran operational and sustainment costs. In December 2006 the IAT unanimously recommended that for, at least the next 20 years, eLoran ?be completed and retained as the national backup system for critical safety of life, national and economic security, and quality of life applications currently reliant on position, time, and/or frequency from GPS.? Among the IAT?s key findings: ?eLoran is the only cost-effective backup for national needs; it is completely interoperable with and independent of GPS, with different propagation and failure mechanisms, plus significantly superior robustness to radio frequency interference and jamming.? Despite the report?s acceptance by the Bush administration, which relied on it for the DHS decision to move forward with eLoran, a summary of the IAT findings and supporting charts was only released in May. Parkinson told Inside GNSS that he estimates the probability of Congress approving eLoran at 75 to 80 percent. Currently, the Radio Technical Commission for Maritime Services (RTCM) is developing performance standards for eLoran in the maritime environment. eLoran also has strong support from the General Lighthouse Authorities (GLA) of the UK and Ireland (equivalent to USCG for maritime safety, which have committed to e-Navigation for maritime safety, using GPS/DGPS as primary input, eLoran as secondary or backup, and electronic charting. ---------------------------- Have Fun, Brooke Clarke http://www.prc68.com Mike Monett wrote: > An article in NetWork World discusses performance degredation in the > new Lockheed-built GPS IIR-2 satellite. Apparently. the new L5 > transmissions are interfering with other signals from the satellite. > > This reduces the accuracy an order of magnitude, from 2 feet to 20 > feet. It should have a corresponding effect on the accuracy of the > decoded time signals. > > The Air Force said it has identified several parameters in the GPS > IIR-20 (M)'s navigation message that can be corrected and is > studying the impact these may have on military and civil GPS users. > > Presumably, the problem will be corrected in the 12 Boeing GPS > satellites currently being built that also feature the L5 signal. > > The article discusses issues such as delays due to techical > problems, cost overruns, and aging of the fleet. These could affect > system performance in the future. > > However, Col. Dave Buckman stated > > "The issue is under control. We are working hard to get out the > word. The issue is not whether GPS will stop working. There's only a > small risk we will not continue to exceed our performance standard," > he said. > > http://www.networkworld.com/community/node/42767 > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From brooke at pacific.net Thu Jun 18 17:00:00 2009 From: brooke at pacific.net (Brooke Clarke) Date: Thu, 18 Jun 2009 10:00:00 -0700 Subject: [time-nuts] Satellite Glitch Rekindles GPS Concerns In-Reply-To: References: Message-ID: <4A3A7290.1080902@pacific.net> Hi again Mike: The IIR-2 satellite was launched in order to meet a deadline rather than when it was truly fully operational. The L5 module is an add on and can not run at full power. So this is not a representative of the future sats. Have Fun, Brooke Clarke http://www.prc68.com Mike Monett wrote: > An article in NetWork World discusses performance degredation in the > new Lockheed-built GPS IIR-2 satellite. Apparently. the new L5 > transmissions are interfering with other signals from the satellite. > > This reduces the accuracy an order of magnitude, from 2 feet to 20 > feet. It should have a corresponding effect on the accuracy of the > decoded time signals. > > The Air Force said it has identified several parameters in the GPS > IIR-20 (M)'s navigation message that can be corrected and is > studying the impact these may have on military and civil GPS users. > > Presumably, the problem will be corrected in the 12 Boeing GPS > satellites currently being built that also feature the L5 signal. > > The article discusses issues such as delays due to techical > problems, cost overruns, and aging of the fleet. These could affect > system performance in the future. > > However, Col. Dave Buckman stated > > "The issue is under control. We are working hard to get out the > word. The issue is not whether GPS will stop working. There's only a > small risk we will not continue to exceed our performance standard," > he said. > > http://www.networkworld.com/community/node/42767 > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From ssybert at kb1fxy.us Thu Jun 18 17:23:02 2009 From: ssybert at kb1fxy.us (Scott A Sybert) Date: Thu, 18 Jun 2009 10:23:02 -0700 Subject: [time-nuts] FS: Brandywine GPS-4 Units & Antennas - 2 sets available Message-ID: <15D717421F0B004A82877D8DFEDF912B058ACE@ex14.hostedexchange.local> Hi Guys, I didn't think I'd see anymore of these but I have two more Brandywine GPS-4 units available with brand new Panasonic antennas and coax kits. Same price as last time... $400 for the GPS and $40 for the antenna kit. As usual, shipping is always free (US only. International shipping will be additional). I prefer personal checks or money orders but will accept paypal for an additional 3%. If anyone is interested, please send me an email off the list. Regards, Scott KB1FXY ssybert at kb1fxy.us From cdelect at juno.com Thu Jun 18 18:13:11 2009 From: cdelect at juno.com (Corby Dawson) Date: Thu, 18 Jun 2009 11:13:11 -0700 Subject: [time-nuts] DMTD question Message-ID: <20090618.111311.3600.0.cdelect@juno.com> Hi, The delay circuit consists of toggle switch increments of 1 thru 180 degrees in binary steps (using differing lengths of miniature coax cable) as well as a fine adjustment that consists of a couple transistors with varactors. These are built into the unit inside sealed cases and with the unit in the rack with covers on the drift is minimal. (I don't ever turn the unit off) I have made plots of oscillator 1 against oscillator 2 and get a 1 second stability of around 3.50 X10-13th. Will be making some more measurements between an HP 5065A and HP 5071A high stability. Corby ____________________________________________________________ Come clean with a brand new shower. Click now! http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTGcgxgbFBBrsXnexqhVPII1HqjSxmV3sZXXiyKXmSrqeqvyKhcPgU/ From xde-l2g3 at myamail.com Thu Jun 18 17:40:43 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Thu, 18 Jun 2009 14:40:43 -0300 Subject: [time-nuts] Satellite Glitch Rekindles GPS Concerns Message-ID: > Hi Mike: > The current issue of Inside GNSS has two articles about this and > their web page has a new article dated 17 June 2009. > http://www.insidegnss.com/ > Hi again Mike: > The IIR-2 satellite was launched in order to meet a deadline > rather than when it was truly fully operational. The L5 module is > an add on and can not run at full power. So this is not a > representative of the future sats. > Have Fun, > Brooke Clarke Running at full power would make the problem worse, don't you think? This slipped past all the modeling and simulations prior to launch, so as well as fixing the problem, they also have to improve the simulations. Somehow that doesn't seem like such a difficult problem. Overall, I think they did a pretty good job for such a complex system with such incredibly tight performance parameters. At least it still works, with degraded accuracy. And it looks like they can fix it. So it's not like sending a billion-dollar satellite to Mars and having it crash because someone forgot to convert between US and metric values:) Hopefully the L5 addition will help reduce the diurnal variation in ionosphere delays that affect the accuracy of the timing signals. So progess in this area is of interest to us. And thanks for the link to insidegnss. That looks like an excellent resource for updates on the technology. Mike From jfor at quik.com Thu Jun 18 18:41:57 2009 From: jfor at quik.com (J. Forster) Date: Thu, 18 Jun 2009 11:41:57 -0700 (PDT) Subject: [time-nuts] DMTD question In-Reply-To: <20090618.111311.3600.0.cdelect@juno.com> References: <20090618.111311.3600.0.cdelect@juno.com> Message-ID: <1330.12.6.201.172.1245350517.squirrel@popacctsnew.quik.com> Hi Corby, Are you still fixing sick FTS and HP Rb's? Best, -John ======== > Hi, > > The delay circuit consists of toggle switch increments of 1 thru 180 > degrees in binary steps (using differing lengths of miniature coax cable) > as well as a fine adjustment that consists of a couple transistors with > varactors. These are built into the unit inside sealed cases and with the > unit in the rack with covers on the drift is minimal. (I don't ever turn > the unit off) > > I have made plots of oscillator 1 against oscillator 2 and get a 1 second > stability of around 3.50 X10-13th. > > Will be making some more measurements between an HP 5065A and HP 5071A > high stability. > > Corby From Murray.Greenman at rakon.com Thu Jun 18 18:45:27 2009 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Fri, 19 Jun 2009 06:45:27 +1200 Subject: [time-nuts] Lady Heather question Message-ID: John/Mark, I don't own a Thunderbolt, but I do have a very nice Trimble NTGS50AA GPSDO which works very well, and it also operates very nicely with TBOLTMON, in both TSIP and SCPI modes. However, I've just fired up Lady Heather V2.0 for the first time, and although the program starts, nothing happens. I have a graph graticule at the bottom, and a blank black area above with just a few things written on it, such as the graph legend. No sign of the wealth of data shown in the help file screen shot, nor any graph data, even after waiting quite a while. I tried both the Win version and the DOS version, and they behave the same. My test computer is an old IBM Aptiva with 450MHz 586 processor, running Win XP. I use COM2 and the program seems happy with that, and everything works fine with TBOLTMON. My next step is to drag out a laptop and spy on the comms between the computer and GPSDO to see what's going on (if anything). I know this is a big ask, but any suggestions as to what might be happening? 73, Murray ZL1BPU From cdelect at juno.com Thu Jun 18 18:45:33 2009 From: cdelect at juno.com (Corby Dawson) Date: Thu, 18 Jun 2009 11:45:33 -0700 Subject: [time-nuts] toko tk11650nt to-92 5v regulator data Message-ID: <20090618.114533.3600.1.cdelect@juno.com> I've built a circuit using a toko tk11650nt voltage regulator in a TO-92 package I got from Digikey a few years back. I need to know the max input voltage and the pinout to verify before I power the circuit up! Can anyone help? Corby ____________________________________________________________ Workers Compensation Legal Advice. Click here http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTOcqGnus3WuGGVpy1drJqjFGdCoqSAw9mciZDz4KSiL7dpOC3PGRS/ From jherrero at hvsistemas.es Thu Jun 18 19:20:25 2009 From: jherrero at hvsistemas.es (Javier Herrero) Date: Thu, 18 Jun 2009 21:20:25 +0200 Subject: [time-nuts] toko tk11650nt to-92 5v regulator data In-Reply-To: <20090618.114533.3600.1.cdelect@juno.com> References: <20090618.114533.3600.1.cdelect@juno.com> Message-ID: <4A3A9379.7020409@hvsistemas.es> This is the datasheet for the SOT-89 part http://www.cbtricks.com/radios/galaxy/datasheets/ic/pdf/tk11650.pdf Sipex seemed to have a pin compatible part, SPX116, this is the datasheet including TO-92 pinout http://www.datasheetarchive.com/pdf/Datasheet-021/DSA00376153.pdf Best regards, Javier Corby Dawson escribi?: > I've built a circuit using a toko tk11650nt voltage regulator in a TO-92 > package I got from Digikey a few years back. > > I need to know the max input voltage and the pinout to verify before I > power the circuit up! > > Can anyone help? > > Corby > ____________________________________________________________ > Workers Compensation Legal Advice. Click here > http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTOcqGnus3WuGGVpy1drJqjFGdCoqSAw9mciZDz4KSiL7dpOC3PGRS/ > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > -- ------------------------------------------------------------------------ Javier Herrero EMAIL: jherrero at hvsistemas.com HV Sistemas S.L. PHONE: +34 949 336 806 Los Charcones, 17A FAX: +34 949 336 792 19170 El Casar - Guadalajara - Spain WEB: http://www.hvsistemas.com From hmurray at megapathdsl.net Thu Jun 18 19:41:58 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Thu, 18 Jun 2009 12:41:58 -0700 Subject: [time-nuts] toko tk11650nt to-92 5v regulator data In-Reply-To: Message from Corby Dawson of "Thu, 18 Jun 2009 11:45:33 PDT." <20090618.114533.3600.1.cdelect@juno.com> Message-ID: <20090618194159.D4188BCEF@ip-64-139-1-69.sjc.megapath.net> > ... I got from Digikey a few years back. I recommend pack-rat mode. Whenever you order a part, grab a copy of the data sheet. Disks are cheap. If your collection gets big enough, you may have to spend some time organizing it. -- These are my opinions, not necessarily my employer's. I hate spam. From ernieperes at aol.com Thu Jun 18 20:12:46 2009 From: ernieperes at aol.com (ernieperes at aol.com) Date: Thu, 18 Jun 2009 16:12:46 -0400 Subject: [time-nuts] Lady Heather question In-Reply-To: References: Message-ID: <8CBBE6847C2E082-11F8-CD3@WEBMAIL-MC18.sysops.aol.com> HI Murray, got the same problem and found that the program looks as default COM1 port....... Please chk and change port. Rgds Ernie. -----Original Message----- From: Murray Greenman To: jmiles at pop.net; holrum at hotmail.com Cc: time-nuts at febo.com Sent: Thu, Jun 18, 2009 8:45 pm Subject: [time-nuts] Lady Heather question John/Mark, I don't own a Thunderbolt, but I do have a very nice Trimble NTGS50AA GPSDO which works very well, and it also operates very nicely with TBOLTMON, in both TSIP and SCPI modes. However, I've just fired up Lady Heather V2.0 for the first time, and although the program starts, nothing happens. I have a graph graticule at the bottom, and a blank black area above with just a few things written on it, such as the graph legend. No sign of the wealth of data shown in the help file screen shot, nor any graph data, even after waiting quite a while. I tried both the Win version and the DOS version, and they behave the same. My test computer is an old IBM Aptiva with 450MHz 586 processor, running Win XP. I use COM2 and the program seems happy with that, and everything works fine with TBOLTMON. My next step is to drag out a laptop and spy on the comms between the computer and GPSDO to see what's going on (if anything). I know this is a big ask, but any suggestions as to what might be happening? 73, Murray ZL1BPU _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From jmiles at pop.net Thu Jun 18 23:17:21 2009 From: jmiles at pop.net (John Miles) Date: Thu, 18 Jun 2009 16:17:21 -0700 Subject: [time-nuts] Lady Heather question In-Reply-To: <8CBBE6847C2E082-11F8-CD3@WEBMAIL-MC18.sysops.aol.com> Message-ID: Usually LH will time out and give you an error message if the port selection is the only problem. I'm not familiar with the NTGS50AA, but given that it's also from Trimble, my guess is that its TSIP implementation is at least somewhat different from the Thunderbolt's, and that TBOLTMON knows how to deal with those differences while LH doesn't. If you're able to get to the bottom of the issue, let Mark and/or myself know and maybe we can work around it. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of ernieperes at aol.com > Sent: Thursday, June 18, 2009 1:13 PM > To: time-nuts at febo.com > Subject: Re: [time-nuts] Lady Heather question > > > HI Murray, > > got the same problem and found that the program looks as default > COM1 port....... > Please chk and change port. > > Rgds Ernie. > > > -----Original Message----- > From: Murray Greenman > To: jmiles at pop.net; holrum at hotmail.com > Cc: time-nuts at febo.com > Sent: Thu, Jun 18, 2009 8:45 pm > Subject: [time-nuts] Lady Heather question > > > > John/Mark, > > I don't own a Thunderbolt, but I do have a very nice Trimble NTGS50AA > GPSDO which works very well, and it also operates very nicely with > TBOLTMON, in both TSIP and SCPI modes. > > However, I've just fired up Lady Heather V2.0 for the first time, and > although the program starts, nothing happens. I have a graph graticule > at the bottom, and a blank black area above with just a few things > written on it, such as the graph legend. No sign of the wealth of data > shown in the help file screen shot, nor any graph data, even after > waiting quite a while. > > I tried both the Win version and the DOS version, and they behave the > same. My test computer is an old IBM Aptiva with 450MHz 586 processor, > running Win XP. I use COM2 and the program seems happy with that, and > everything works fine with TBOLTMON. > > My next step is to drag out a laptop and spy on the comms between the > computer and GPSDO to see what's going on (if anything). I know this is > a big ask, but any suggestions as to what might be happening? > > 73, > > Murray ZL1BPU > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From frledda at verizon.net Thu Jun 18 13:06:13 2009 From: frledda at verizon.net (Francesco Ledda) Date: Thu, 18 Jun 2009 08:06:13 -0500 Subject: [time-nuts] Z3805 initial behaviour after power up revised In-Reply-To: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> Message-ID: Aging cannot be predicted! If it could be predicetd, there would be no aging. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Ulrich Bangert Sent: Thursday, June 18, 2009 3:04 AM To: 'Discussion of precise time and frequency measurement' Subject: [time-nuts] Z3805 initial behaviour after power up revised Gents, one of the papers suggested by Brian says: ------------------------------------------- SmartClock monitors the frequency control variable of the internal oscillator while it is locked to the external reference. This gives a measure of the frequency difference between the internal oscillator, if it is free-running, and the external reference over time. The resulting measurements include the effects of random noise in the oscillator, the measurement circuitry, and any noise in the external reference as well as any aging and environmental effects in the oscillator. From this information, SmartClock makes a continuous prediction of clock error over time. ------------------------------------------- The big question is: If the EFC signal includes this all information, how does the algo manage to extract the individual informations? After having a look at the PPS TI and the EFC of my Z3805 I am beginning to get a clue of it (the quirks on the EFC signal heve been removed): The SmartClock algo seems to set the loop time constants to a large value in the beginning. In other words: It measures the overall oscillator frequency influencing effects with a lowpass filter applied that has a very low cutoff frequency. Only effects which's frequency are sufficient lower then the cutoff pass the filter. Seems as if the SmartClock uses this filter setting to exclude any noise related effect and any environmental effect and make the measurement see ONLY the oscillator's aging. Once it has learned enough about the aging process it will be able to predict aging. Having reached this state it will be able to apply his knowledge about aging to further TI measurements and subtract the "aging part" of it, leaving mostly the environmental (which is mostly temperature) part. Having a model for the aging the Algo can now model the temperature dependence. However, a precondition for this were that the measurement sees the temperature effects and that the ambient temperature is measured independently. For that reason I expect the Algo will reduce its loop time constant within the next time to make the temperature effect get through the lowpass. Any bets on that? Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert > Gesendet: Donnerstag, 18. Juni 2009 08:29 > An: 'Discussion of precise time and frequency measurement' > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > Brian, > > > You may also want to search for HP An1279, it also goes over HP > > smartclock operation, and look for a paper titled "the Global > > Positioning System and HP SmartClock" by John A. Kusters. > > In the meantime I have not only found these but also "Smart > Clock: A New Time" by David Allan et al which shows that > "Smart Clock" is originally a NIST invention & patent and > explains very well how it works. Perhaps what I and You have > seen is a direct consequence of applying the Smart Clock algorithm. > > Best regards > Ulrich > > > > -----Ursprungliche Nachricht----- > > Von: time-nuts-bounces at febo.com > > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby > > Gesendet: Donnerstag, 18. Juni 2009 01:51 > > An: Discussion of precise time and frequency measurement > > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > > > > > They do not talk about driving the frequency off, but they > > warn to keep > > the receiver locked the first 24 hours, so it can determine how the > > oscillator ages. Its in the section on "holdover" (page 52 > > of the PDF , > > page 3-8 of the user guide). > > > > You may also want to search for HP An1279, it also goes over HP > > smartclock operation, and look for a paper titled "the Global > > Positioning System and HP SmartClock" by John A. Kusters. > > > > If you have a broadband connection, I can email you each > one, if that > > will help. > > > > Brian > > > > Ulrich Bangert wrote: > > > Brian, > > > > > > thanks for your information! > > > > > > > > >> algorithm. From what I read about the smart clock, it > takes 5 days > > >> for it to complete its initial learning cycle and then its > > >> > > > continuously > > > > > >> refining. > > >> > > > > > > Is that from the Z3801 manual, which I have available, or > > do you have > > > any other in depth information source? > > > > > > Best regards > > > Ulrich > > > > > > > > >> -----Ursprungliche Nachricht----- > > >> Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] > > >> Im Auftrag von Brian Kirby > > >> Gesendet: Mittwoch, 17. Juni 2009 16:58 > > >> An: Discussion of precise time and frequency measurement > > >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up > > >> > > >> > > >> Ulrich, > > >> > > >> I have two Z3801A and both of them act close to what you > describe > > >> in the first 24 hours of power up. I believe its part of the > > disciplining > > >> algorithm. From what I read about the smart clock, it takes > > >> 5 days for > > >> it to complete its initial learning cycle and then its > > continuously > > >> refining. > > >> > > >> Brian > > >> > > >> _______________________________________________ > > >> time-nuts mailing list -- time-nuts at febo.com > > >> To unsubscribe, go to > > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > >> and follow the instructions there. > > >> > > > > > > > > > _______________________________________________ > > > time-nuts mailing list -- time-nuts at febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From imp at bsdimp.com Fri Jun 19 03:28:03 2009 From: imp at bsdimp.com (M. Warner Losh) Date: Thu, 18 Jun 2009 21:28:03 -0600 (MDT) Subject: [time-nuts] Z3805 initial behaviour after power up revised In-Reply-To: References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> Message-ID: <20090618.212803.-146244266.imp@bsdimp.com> In message: "Francesco Ledda" writes: : Aging cannot be predicted! If it could be predicetd, there would be no : aging. Actually, if aging could be predicted perfectly, there'd be perfect holdover (which I think is saying the same thing). Aging can be predicted imperfectly in the short term, but the amount of imperfect grows with the time you're without data... Warner : : -----Original Message----- : From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On : Behalf Of Ulrich Bangert : Sent: Thursday, June 18, 2009 3:04 AM : To: 'Discussion of precise time and frequency measurement' : Subject: [time-nuts] Z3805 initial behaviour after power up revised : : : Gents, : : one of the papers suggested by Brian says: : ------------------------------------------- : SmartClock monitors the frequency control variable of the internal : oscillator while it is locked to the external reference. This gives a : measure of the frequency difference between the internal oscillator, if it : is free-running, and the external reference over time. The resulting : measurements include the effects of random noise in the oscillator, the : measurement circuitry, and any noise in the external reference as well as : any aging and environmental effects in the oscillator. From this : information, SmartClock makes a continuous prediction of clock error over : time. : ------------------------------------------- : : The big question is: If the EFC signal includes this all information, how : does the algo manage to extract the individual informations? After having a : look at the PPS TI and the EFC of my Z3805 I am beginning to get a clue of : it (the quirks on the EFC signal heve been removed): : : The SmartClock algo seems to set the loop time constants to a large value in : the beginning. In other words: It measures the overall oscillator frequency : influencing effects with a lowpass filter applied that has a very low cutoff : frequency. Only effects which's frequency are sufficient lower then the : cutoff pass the filter. Seems as if the SmartClock uses this filter setting : to exclude any noise related effect and any environmental effect and make : the measurement see ONLY the oscillator's aging. : : Once it has learned enough about the aging process it will be able to : predict aging. Having reached this state it will be able to apply his : knowledge about aging to further TI measurements and subtract the "aging : part" of it, leaving mostly the environmental (which is mostly temperature) : part. : : Having a model for the aging the Algo can now model the temperature : dependence. However, a precondition for this were that the measurement sees : the temperature effects and that the ambient temperature is measured : independently. For that reason I expect the Algo will reduce its loop time : constant within the next time to make the temperature effect get through the : lowpass. Any bets on that? : : Best regards : Ulrich Bangert : : > -----Ursprungliche Nachricht----- : > Von: time-nuts-bounces at febo.com : > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert : > Gesendet: Donnerstag, 18. Juni 2009 08:29 : > An: 'Discussion of precise time and frequency measurement' : > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up : > : > : > Brian, : > : > > You may also want to search for HP An1279, it also goes over HP : > > smartclock operation, and look for a paper titled "the Global : > > Positioning System and HP SmartClock" by John A. Kusters. : > : > In the meantime I have not only found these but also "Smart : > Clock: A New Time" by David Allan et al which shows that : > "Smart Clock" is originally a NIST invention & patent and : > explains very well how it works. Perhaps what I and You have : > seen is a direct consequence of applying the Smart Clock algorithm. : > : > Best regards : > Ulrich : > : > : > > -----Ursprungliche Nachricht----- : > > Von: time-nuts-bounces at febo.com : > > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby : > > Gesendet: Donnerstag, 18. Juni 2009 01:51 : > > An: Discussion of precise time and frequency measurement : > > Betreff: Re: [time-nuts] Z3805 initial behaviour after power up : > > : > > : > > They do not talk about driving the frequency off, but they : > > warn to keep : > > the receiver locked the first 24 hours, so it can determine how the : > > oscillator ages. Its in the section on "holdover" (page 52 : > > of the PDF , : > > page 3-8 of the user guide). : > > : > > You may also want to search for HP An1279, it also goes over HP : > > smartclock operation, and look for a paper titled "the Global : > > Positioning System and HP SmartClock" by John A. Kusters. : > > : > > If you have a broadband connection, I can email you each : > one, if that : > > will help. : > > : > > Brian : > > : > > Ulrich Bangert wrote: : > > > Brian, : > > > : > > > thanks for your information! : > > > : > > > : > > >> algorithm. From what I read about the smart clock, it : > takes 5 days : > > >> for it to complete its initial learning cycle and then its : > > >> : > > > continuously : > > > : > > >> refining. : > > >> : > > > : > > > Is that from the Z3801 manual, which I have available, or : > > do you have : > > > any other in depth information source? : > > > : > > > Best regards : > > > Ulrich : > > > : > > > : > > >> -----Ursprungliche Nachricht----- : > > >> Von: time-nuts-bounces at febo.com : > [mailto:time-nuts-bounces at febo.com] : > > >> Im Auftrag von Brian Kirby : > > >> Gesendet: Mittwoch, 17. Juni 2009 16:58 : > > >> An: Discussion of precise time and frequency measurement : > > >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up : > > >> : > > >> : > > >> Ulrich, : > > >> : > > >> I have two Z3801A and both of them act close to what you : > describe : > > >> in the first 24 hours of power up. I believe its part of the : > > disciplining : > > >> algorithm. From what I read about the smart clock, it takes : > > >> 5 days for : > > >> it to complete its initial learning cycle and then its : > > continuously : > > >> refining. : > > >> : > > >> Brian : > > >> : > > >> _______________________________________________ : > > >> time-nuts mailing list -- time-nuts at febo.com : > > >> To unsubscribe, go to : > > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts : > > >> and follow the instructions there. : > > >> : > > > : > > > : > > > _______________________________________________ : > > > time-nuts mailing list -- time-nuts at febo.com : > > > To unsubscribe, go to : > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts : > > > and follow the instructions there. : > > > : > > > : > > _______________________________________________ : > > time-nuts mailing list -- time-nuts at febo.com : > > To unsubscribe, go to : > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts : > > and follow the instructions there. : > : > : > _______________________________________________ : > time-nuts mailing list -- time-nuts at febo.com : > To unsubscribe, go to : > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts : > and follow the instructions there. : : : _______________________________________________ : time-nuts mailing list -- time-nuts at febo.com : To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts : and follow the instructions there. : : From cfharris at erols.com Fri Jun 19 04:41:30 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 19 Jun 2009 00:41:30 -0400 Subject: [time-nuts] Bulova PCOXO... Message-ID: <4A3B16FA.5000404@erols.com> Hi, I'm in the process of repairing a 10MHz Bulova PCOXO part number: 298248-3 serial number: 77-3129 It runs off of -15V for both the oscillator and oven. Hardly a timenuts oscillator, but I would like it work never the less. Does anyone have a schematic? It would be easier to start with a schematic, but if not, I will just have to trace it out. Thanks! -Chuck Harris From bruce.griffiths at xtra.co.nz Fri Jun 19 04:53:54 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 19 Jun 2009 16:53:54 +1200 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <20090618.212803.-146244266.imp@bsdimp.com> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> Message-ID: <4A3B19E2.8090903@xtra.co.nz> For the benefit of HP5370A and/or HP5370B users I have added a webpage detailing the characteristics and diagnosis of a fault that my HP5370A recently developed. With the 10MHz rear panel output connected to both inputs it developed an overange error when set to measure the time delay between the START and STOP inputs. Details are on the web page: http://www.ko4bb.com/~bruce/HP5370_Faults.html At Didier's suggestion I've also included a link detailing the imaging setup and camera settings etc used to acquire the chip image on the above page. Whilst it is possible to obtain good quality images with less precise multiaxis positioner than those used, at least it is very easy using such equipment The chip image confirms the diagnosis inferred from measurements of various signals within the 5370A. Replacing A22U21 cured the problem, Bruce From dforbes at dakotacom.net Fri Jun 19 06:12:20 2009 From: dforbes at dakotacom.net (David Forbes) Date: Thu, 18 Jun 2009 23:12:20 -0700 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B19E2.8090903@xtra.co.nz> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> Message-ID: At 4:53 PM +1200 6/19/09, Bruce Griffiths wrote: > >http://www.ko4bb.com/~bruce/HP5370_Faults.html > > > >Replacing A22U21 cured the problem, > >Bruce Bruce, This sounds like a good excuse to learn how the wire bonder in the office next to mine works. -- --David Forbes, Tucson, AZ http://www.cathodecorner.com/ From robert8rpi at yahoo.co.uk Fri Jun 19 06:54:24 2009 From: robert8rpi at yahoo.co.uk (Robert Atkinson) Date: Fri, 19 Jun 2009 06:54:24 +0000 (GMT) Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis Message-ID: <521579.39338.qm@web27107.mail.ukl.yahoo.com> Hi Bruce, I once had a similar problem with AD595 theromcouple IC's we had a whole bunch of them on a car when suddenly 2 at the rear kept failing. After the third failure I investigated further and it looked like on all 3 the feedback pin(8)had gone open circuit. I prised them open and on each, the bondwire had broken. We put this down to noise levels or possibly local supersonic buffeting exciting a resonance in that particular bond wire. A "blob" of high temperature RTV on the chip seemed to cure the problem. Hermetic packages have their own issues. Robert G8RPI. --- On Fri, 19/6/09, Bruce Griffiths wrote: > From: Bruce Griffiths > Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis > To: "Discussion of precise time and frequency measurement" > Date: Friday, 19 June, 2009, 5:53 AM > For the benefit of HP5370A and/or > HP5370B users I have added a webpage > detailing the characteristics and diagnosis of a fault that > my HP5370A > recently developed. > With the 10MHz rear panel output connected to both inputs > it developed > an overange error when set to measure the time delay > between the START > and STOP inputs. > Details are on the? web page: > > http://www.ko4bb.com/~bruce/HP5370_Faults.html > > > At Didier's suggestion I've also included a link detailing > the imaging > setup and camera settings etc used to acquire the chip > image on the > above page. > Whilst it is possible to obtain good quality images with > less precise > multiaxis positioner than those used, at least it is very > easy using > such equipment > The chip image confirms the diagnosis inferred from > measurements of > various signals within the 5370A. > > Replacing A22U21 cured the problem, > > Bruce > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From df6jb at ulrich-bangert.de Fri Jun 19 06:58:39 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Fri, 19 Jun 2009 08:58:39 +0200 Subject: [time-nuts] Bulova PCOXO... In-Reply-To: <4A3B16FA.5000404@erols.com> Message-ID: <345963452D914332AABA000CC7C1337F@athlon> Bulova, let the name alone... When I was a child a person in the neighbourhood owned a "BULOVE ACCUTRON" known as the "humming wristwatch". This was the first (and only?) wristwatch to use a mechanical tuning fork running at a few hundret Hertz instead of a conventional balance spring. Read more at http://en.wikipedia.org/wiki/Bulova Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Chuck Harris > Gesendet: Freitag, 19. Juni 2009 06:42 > An: Discussion of precise time and frequency measurement > Betreff: [time-nuts] Bulova PCOXO... > > > Hi, > > I'm in the process of repairing a 10MHz Bulova PCOXO > > part number: 298248-3 > serial number: 77-3129 > > It runs off of -15V for both the oscillator and oven. > > Hardly a timenuts oscillator, but I would like it work > never the less. > > Does anyone have a schematic? It would be easier to > start with a schematic, but if not, I will just have > to trace it out. > > Thanks! > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From rexa at sonic.net Fri Jun 19 07:46:53 2009 From: rexa at sonic.net (Rex) Date: Fri, 19 Jun 2009 00:46:53 -0700 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B19E2.8090903@xtra.co.nz> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> Message-ID: <4A3B426D.5080001@sonic.net> Bruce, I've never seen you post a new thread as a response to an existing, unrelated thread, as you've done here. You are not the first to do this, but I thought you might be aware of these subtleties. In the spirit of quasi-related posts... On the 5370A part, I recently bought one cheap and it sort of works but seems very noisey in its lower order digit readings; clean external ref doesn't help. I haven't looked at obvious things like the power supply yet, but I'm curious if the group has any thoughts of common problems to look for. Bruce Griffiths wrote: >For the benefit of HP5370A and/or HP5370B users I have added a webpage >detailing the characteristics and diagnosis of a fault that my HP5370A >recently developed. >With the 10MHz rear panel output connected to both inputs it developed >an overange error when set to measure the time delay between the START >and STOP inputs. >Details are on the web page: > >http://www.ko4bb.com/~bruce/HP5370_Faults.html > > >At Didier's suggestion I've also included a link detailing the imaging >setup and camera settings etc used to acquire the chip image on the >above page. >Whilst it is possible to obtain good quality images with less precise >multiaxis positioner than those used, at least it is very easy using >such equipment >The chip image confirms the diagnosis inferred from measurements of >various signals within the 5370A. > >Replacing A22U21 cured the problem, > >Bruce > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > > > From REMartinson at rcn.com Fri Jun 19 07:48:29 2009 From: REMartinson at rcn.com (Bob Martinson) Date: Fri, 19 Jun 2009 03:48:29 -0400 Subject: [time-nuts] Bulova PCOXO... In-Reply-To: <345963452D914332AABA000CC7C1337F@athlon> Message-ID: I still have one I bought for around $125 or 150 in Hawail in 1966. I'm sure with a fresh battery it wud still work.. I have the see-thru model. Bob, K1REM -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Ulrich Bangert Sent: Friday, June 19, 2009 2:59 AM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Bulova PCOXO... Bulova, let the name alone... When I was a child a person in the neighbourhood owned a "BULOVE ACCUTRON" known as the "humming wristwatch". This was the first (and only?) wristwatch to use a mechanical tuning fork running at a few hundret Hertz instead of a conventional balance spring. Read more at http://en.wikipedia.org/wiki/Bulova Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Chuck Harris > Gesendet: Freitag, 19. Juni 2009 06:42 > An: Discussion of precise time and frequency measurement > Betreff: [time-nuts] Bulova PCOXO... > > > Hi, > > I'm in the process of repairing a 10MHz Bulova PCOXO > > part number: 298248-3 > serial number: 77-3129 > > It runs off of -15V for both the oscillator and oven. > > Hardly a timenuts oscillator, but I would like it work > never the less. > > Does anyone have a schematic? It would be easier to > start with a schematic, but if not, I will just have > to trace it out. > > Thanks! > > -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.78/2185 - Release Date: 06/18/09 05:53:00 From bruce.griffiths at xtra.co.nz Fri Jun 19 08:09:28 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 19 Jun 2009 20:09:28 +1200 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B426D.5080001@sonic.net> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> <4A3B426D.5080001@sonic.net> Message-ID: <4A3B47B8.2000706@xtra.co.nz> Bruce Rex wrote: > Bruce, > > I've never seen you post a new thread as a response to an existing, > unrelated thread, as you've done here. You are not the first to do > this, but I thought you might be aware of these subtleties. > I was being lazy. How can you tell, looking at the message source I wasn't able to see any indication of this? > In the spirit of quasi-related posts... > > On the 5370A part, I recently bought one cheap and it sort of works > but seems very noisey in its lower order digit readings; clean > external ref doesn't help. I haven't looked at obvious things like the > power supply yet, but I'm curious if the group has any thoughts of > common problems to look for. > One cause of this can be misalignment of the 10MHz to 200MHz frequency multiplier chain filters. Another thing to look at (if you are using the rear panel 10MHz output) is the signal may not be clean enough in which case checking that the output filter is working properly and/or using an external bandpass filter may be necessary to cleanup the signal sufficiently. What is the indicated std deviation of the delay between the STAR and STOP inputs when connecting the rear panel 10MHz signal to both START and STOP inputs using the STAR COM position of the channel mode switch? > > Bruce Griffiths wrote: > >> For the benefit of HP5370A and/or HP5370B users I have added a webpage >> detailing the characteristics and diagnosis of a fault that my HP5370A >> recently developed. >> With the 10MHz rear panel output connected to both inputs it developed >> an overange error when set to measure the time delay between the START >> and STOP inputs. >> Details are on the web page: >> >> http://www.ko4bb.com/~bruce/HP5370_Faults.html >> >> >> At Didier's suggestion I've also included a link detailing the imaging >> setup and camera settings etc used to acquire the chip image on the >> above page. >> Whilst it is possible to obtain good quality images with less precise >> multiaxis positioner than those used, at least it is very easy using >> such equipment >> The chip image confirms the diagnosis inferred from measurements of >> various signals within the 5370A. >> >> Replacing A22U21 cured the problem, >> >> Bruce >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Bruce From jmiles at pop.net Fri Jun 19 08:10:35 2009 From: jmiles at pop.net (John Miles) Date: Fri, 19 Jun 2009 01:10:35 -0700 Subject: [time-nuts] HP5370A self test fault characteristics anddiagnosis In-Reply-To: <4A3B426D.5080001@sonic.net> Message-ID: > On the 5370A part, I recently bought one cheap and it sort of works but > seems very noisey in its lower order digit readings; clean external ref > doesn't help. I haven't looked at obvious things like the power supply > yet, but I'm curious if the group has any thoughts of common problems to > look for. What mode are you observing the noise in? Noisy LSDs on a 5370 are normal in many cases. -- john, KE5FX From rexa at sonic.net Fri Jun 19 09:16:00 2009 From: rexa at sonic.net (Rex) Date: Fri, 19 Jun 2009 02:16:00 -0700 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B47B8.2000706@xtra.co.nz> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> <4A3B426D.5080001@sonic.net> <4A3B47B8.2000706@xtra.co.nz> Message-ID: <4A3B5750.3030807@sonic.net> Bruce Griffiths wrote: >Bruce > >Rex wrote: > > >>Bruce, >> >>I've never seen you post a new thread as a response to an existing, >>unrelated thread, as you've done here. You are not the first to do >>this, but I thought you might be aware of these subtleties. >> >> >> > >I was being lazy. >How can you tell, looking at the message source I wasn't able to see any >indication of this? > > > I don't know enough about what is in the headers to explain the posting issue -- one of the entries ties back to the previous message, I think. The way I can tell is reading with the Thunderbird mail program, the new message shows up still under the earlier thread but with the new subject. I think I have seen similar with other mail programs. Thanks for the reply to my 5370A question. I'll study on it. Since the box sort of works, I think it should be fixable. From rexa at sonic.net Fri Jun 19 09:32:46 2009 From: rexa at sonic.net (Rex) Date: Fri, 19 Jun 2009 02:32:46 -0700 Subject: [time-nuts] HP5370A self test fault characteristics anddiagnosis In-Reply-To: References: Message-ID: <4A3B5B3E.30600@sonic.net> John Miles wrote: >>On the 5370A part, I recently bought one cheap and it sort of works but >>seems very noisey in its lower order digit readings; clean external ref >>doesn't help. I haven't looked at obvious things like the power supply >>yet, but I'm curious if the group has any thoughts of common problems to >>look for. >> >> > >What mode are you observing the noise in? Noisy LSDs on a 5370 are normal >in many cases. > >-- john, KE5FX > > > I have a 5334B and looking at the same signal it seems more stable. From memory (I haven't tried it recently) the 5370 had 3 or 4 unstable low order digits. Even selecting high periods or sample size didn't seem to remove noise out of two or three digits. I never used a 5370 before, but this doesn't seem right. I get several random digits even looking at it's own clean 10 MHz external clock. That shouldn't be, should it? From magnus at rubidium.dyndns.org Fri Jun 19 09:40:35 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 19 Jun 2009 11:40:35 +0200 Subject: [time-nuts] Satellite Glitch Rekindles GPS Concerns In-Reply-To: <4A3A7290.1080902@pacific.net> References: <4A3A7290.1080902@pacific.net> Message-ID: <4A3B5D13.10405@rubidium.dyndns.org> Brooke Clarke wrote: > Hi again Mike: > > The IIR-2 satellite was launched in order to meet a deadline rather > than when it was truly fully operational. The L5 module is an add on > and can not run at full power. So this is not a representative of the > future sats. First of all, it's the IIR-20(M). If you look at the article it has both variants, so I think it is just an editorial mistake. The problem is how the L1 tracking is affected. Exactly what mecanism shifts the L1 signal is unclear in the material I have seen, but L1 seems shifted. Depending on the elevation in the sky, this shift is more or less apparent. Cheers, Magnus > > Have Fun, > > Brooke Clarke > http://www.prc68.com > > Mike Monett wrote: >> An article in NetWork World discusses performance degredation in the >> new Lockheed-built GPS IIR-2 satellite. Apparently. the new L5 >> transmissions are interfering with other signals from the satellite. >> >> This reduces the accuracy an order of magnitude, from 2 feet to 20 >> feet. It should have a corresponding effect on the accuracy of the >> decoded time signals. >> >> The Air Force said it has identified several parameters in the GPS >> IIR-20 (M)'s navigation message that can be corrected and is >> studying the impact these may have on military and civil GPS users. >> >> Presumably, the problem will be corrected in the 12 Boeing GPS >> satellites currently being built that also feature the L5 signal. >> >> The article discusses issues such as delays due to techical >> problems, cost overruns, and aging of the fleet. These could affect >> system performance in the future. >> >> However, Col. Dave Buckman stated >> >> "The issue is under control. We are working hard to get out the >> word. The issue is not whether GPS will stop working. There's only a >> small risk we will not continue to exceed our performance standard," >> he said. >> >> http://www.networkworld.com/community/node/42767 >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From rexa at sonic.net Fri Jun 19 09:53:03 2009 From: rexa at sonic.net (Rex) Date: Fri, 19 Jun 2009 02:53:03 -0700 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B47B8.2000706@xtra.co.nz> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> <4A3B426D.5080001@sonic.net> <4A3B47B8.2000706@xtra.co.nz> Message-ID: <4A3B5FFF.7070803@sonic.net> Bruce Griffiths wrote: >What is the indicated std deviation of the delay between the STAR and >STOP inputs when connecting the rear panel 10MHz signal to both START >and STOP inputs using the STAR COM position of the channel mode switch? > > Bruce, I don't think I understand exactly how to measure this. First, let me say that this is a very early 5370A. It doesn't even have a 10544, it has the early crappy reference. Hence, I have been feeding it a better signal to the external ref input. Now, I am assuming you are talking about measuring a version of this reference signal. I think you are saying, put the front panel switch to START COMMON. Are you saying to feed in phase inputs to both Start and Stop inputs? I thought Start Common tied them together. Then I have no clue how to gather a reading for std deviation. Sorry if I am being dense. This counter, though very old, is new to me. Thanks for the help and suggestions. From jmiles at pop.net Fri Jun 19 10:07:33 2009 From: jmiles at pop.net (John Miles) Date: Fri, 19 Jun 2009 03:07:33 -0700 Subject: [time-nuts] HP5370A self test fault characteristics anddiagnosis In-Reply-To: <4A3B5B3E.30600@sonic.net> Message-ID: > I have a 5334B and looking at the same signal it seems more stable. From > memory (I haven't tried it recently) the 5370 had 3 or 4 unstable low > order digits. Even selecting high periods or sample size didn't seem to > remove noise out of two or three digits. > > I never used a 5370 before, but this doesn't seem right. I get several > random digits even looking at it's own clean 10 MHz external clock. That > shouldn't be, should it? The procedure Bruce was describing is basically the jitter test from the manual, at http://cp.literature.agilent.com/litweb/pdf/05370-90031.pdf (this is actually the same copy that David Kirkby scanned a few years ago, hosted by Agilent.) Follow the directions on page 3-11 and 3-12, and post the results, especially from step 15. This jitter figure is usually well under 50 ps in a 5370 that's working properly. -- john, KE5FX From holrum at hotmail.com Fri Jun 19 10:16:12 2009 From: holrum at hotmail.com (Mark Sims) Date: Fri, 19 Jun 2009 10:16:12 +0000 Subject: [time-nuts] Bulova PCOXO... In-Reply-To: References: Message-ID: Actually, that may be more of a problem than you think. These originally ran on a 1.35V mercury battery. A 1.5V alkaline cell can overdrive the tuning fork causing the watch to run fast or not at all. The watch may be able to be adjusted to work with the modern battery or you need to use an "Accucell" battery. This is a standard battery that is mounted in a machined brass holder with a dropping diode. ---------------------------------------- I still have one I bought for around $125 or 150 in Hawail in 1966. I'm sure with a fresh battery it wud still work.. I have the see-thru model. _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From rexa at sonic.net Fri Jun 19 10:40:17 2009 From: rexa at sonic.net (Rex) Date: Fri, 19 Jun 2009 03:40:17 -0700 Subject: [time-nuts] HP5370A self test fault characteristics anddiagnosis In-Reply-To: References: Message-ID: <4A3B6B11.3010101@sonic.net> John Miles wrote: >>I have a 5334B and looking at the same signal it seems more stable. From >>memory (I haven't tried it recently) the 5370 had 3 or 4 unstable low >>order digits. Even selecting high periods or sample size didn't seem to >>remove noise out of two or three digits. >> >>I never used a 5370 before, but this doesn't seem right. I get several >>random digits even looking at it's own clean 10 MHz external clock. That >>shouldn't be, should it? >> >> > >The procedure Bruce was describing is basically the jitter test from the >manual, at http://cp.literature.agilent.com/litweb/pdf/05370-90031.pdf (this >is actually the same copy that David Kirkby scanned a few years ago, hosted >by Agilent.) Follow the directions on page 3-11 and 3-12, and post the >results, especially from step 15. This jitter figure is usually well under >50 ps in a 5370 that's working properly. > >-- john, KE5FX > > > > > Thanks. I think I did the beginning of that, but will need to do it again to get anything accurate to post. Will do. From bruce.griffiths at xtra.co.nz Fri Jun 19 10:46:15 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 19 Jun 2009 22:46:15 +1200 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B5FFF.7070803@sonic.net> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> <4A3B426D.5080001@sonic.net> <4A3B47B8.2000706@xtra.co.nz> <4A3B5FFF.7070803@sonic.net> Message-ID: <4A3B6C77.8040705@xtra.co.nz> Rex wrote: > Bruce Griffiths wrote: > >> What is the indicated std deviation of the delay between the STAR and >> STOP inputs when connecting the rear panel 10MHz signal to both START >> and STOP inputs using the STAR COM position of the channel mode switch? >> >> > Bruce, > > I don't think I understand exactly how to measure this. > > First, let me say that this is a very early 5370A. It doesn't even > have a 10544, it has the early crappy reference. Hence, I have been > feeding it a better signal to the external ref input. > > Now, I am assuming you are talking about measuring a version of this > reference signal. I think you are saying, put the front panel switch > to START COMMON. Are you saying to feed in phase inputs to both Start > and Stop inputs? I thought Start Common tied them together. Then I > have no clue how to gather a reading for std deviation. > Yes, I should have given clearer instructions, just connect the 10MHz out to the START input with the swich selecting both inputs as COMMON. Even with the ECL gate based crystal oscillator (my 5370A has one as well even though its not a very early one, HP seemed to jump back and forth between having a cheap oscillator and having a 10544A as standard) the standard deviation should be less than 100ps. Typically something like 15ps. With an external 10MHz signal connected to both inputs in COMMON the STD deviation will be a little larger perhaps 35ps or so. > Sorry if I am being dense. This counter, though very old, is new to me. > > Thanks for the help and suggestions. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > Bruce From optomatic at rogers.com Fri Jun 19 12:04:04 2009 From: optomatic at rogers.com (Patrick) Date: Fri, 19 Jun 2009 08:04:04 -0400 Subject: [time-nuts] OT favorite signal generator? Message-ID: <4A3B7EB4.9010802@rogers.com> Hey everyone Sorry for the off topic post. I have received great advice in the past with items for my little shop and I can't resist to ask again. I am thinking about buying a signal generator. I suspect that I will mostly use it to inject low uV/mV signals into the amplification stages of the laboratory instruments I service. Any feedback you have would be greatly appreciated-Patrick From jmiles at pop.net Fri Jun 19 12:32:29 2009 From: jmiles at pop.net (John Miles) Date: Fri, 19 Jun 2009 05:32:29 -0700 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B7EB4.9010802@rogers.com> Message-ID: Budget? Freq range? HP 8657As are good general-purpose SGs. Reliable, serviceable, and reasonably clean. Avoid 8656s and 8660s IMHO unless you can get one for next to nothing. If you don't mind getting your hands dirty there have been some inexpensive 8662As on the surplus market lately. They are cleaner than most, have an actual tuning knob, and include sweep capability. They are complex, sometimes maintenance-intensive, and very hard to ship safely, and many of the ones you find on eBay have lived hard lives. -- john, KE5FX > Hey everyone > > Sorry for the off topic post. I have received great advice in the past > with items for my little shop and I can't resist to ask again. > > I am thinking about buying a signal generator. I suspect that I will > mostly use it to inject low uV/mV signals into the amplification stages > of the laboratory instruments I service. > > Any feedback you have would be greatly appreciated-Patrick > From optomatic at rogers.com Fri Jun 19 12:41:15 2009 From: optomatic at rogers.com (Patrick) Date: Fri, 19 Jun 2009 08:41:15 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: References: Message-ID: <4A3B876B.1070603@rogers.com> Thanks John With regard to frequency and price, low frequency is fine for me and I am hoping to buy something for < $250-Patrick John Miles wrote: > Budget? Freq range? > > HP 8657As are good general-purpose SGs. Reliable, serviceable, and > reasonably clean. Avoid 8656s and 8660s IMHO unless you can get one for > next to nothing. > > If you don't mind getting your hands dirty there have been some inexpensive > 8662As on the surplus market lately. They are cleaner than most, have an > actual tuning knob, and include sweep capability. They are complex, > sometimes maintenance-intensive, and very hard to ship safely, and many of > the ones you find on eBay have lived hard lives. > > -- john, KE5FX > > > >> Hey everyone >> >> Sorry for the off topic post. I have received great advice in the past >> with items for my little shop and I can't resist to ask again. >> >> I am thinking about buying a signal generator. I suspect that I will >> mostly use it to inject low uV/mV signals into the amplification stages >> of the laboratory instruments I service. >> >> Any feedback you have would be greatly appreciated-Patrick >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From magnus at rubidium.dyndns.org Fri Jun 19 12:58:51 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 19 Jun 2009 14:58:51 +0200 Subject: [time-nuts] Z3805 initial behaviour after power up revised In-Reply-To: References: Message-ID: <4A3B8B8B.9090701@rubidium.dyndns.org> Francesco Ledda wrote: > Aging cannot be predicted! If it could be predicetd, there would be no > aging. > Not entierly true. Even with a perfectly known aging, only a few oscillators would bother to estimate and correct it. This can never be perfectly done anyway, and there is only so many things you can bring into the model while keeping it economical. There is fairly good clues around. If all was included and handled, it would reduce the effects. Cheers, Magnus > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Ulrich Bangert > Sent: Thursday, June 18, 2009 3:04 AM > To: 'Discussion of precise time and frequency measurement' > Subject: [time-nuts] Z3805 initial behaviour after power up revised > > > Gents, > > one of the papers suggested by Brian says: > ------------------------------------------- > SmartClock monitors the frequency control variable of the internal > oscillator while it is locked to the external reference. This gives a > measure of the frequency difference between the internal oscillator, if it > is free-running, and the external reference over time. The resulting > measurements include the effects of random noise in the oscillator, the > measurement circuitry, and any noise in the external reference as well as > any aging and environmental effects in the oscillator. From this > information, SmartClock makes a continuous prediction of clock error over > time. > ------------------------------------------- > > The big question is: If the EFC signal includes this all information, how > does the algo manage to extract the individual informations? After having a > look at the PPS TI and the EFC of my Z3805 I am beginning to get a clue of > it (the quirks on the EFC signal heve been removed): > > The SmartClock algo seems to set the loop time constants to a large value in > the beginning. In other words: It measures the overall oscillator frequency > influencing effects with a lowpass filter applied that has a very low cutoff > frequency. Only effects which's frequency are sufficient lower then the > cutoff pass the filter. Seems as if the SmartClock uses this filter setting > to exclude any noise related effect and any environmental effect and make > the measurement see ONLY the oscillator's aging. > > Once it has learned enough about the aging process it will be able to > predict aging. Having reached this state it will be able to apply his > knowledge about aging to further TI measurements and subtract the "aging > part" of it, leaving mostly the environmental (which is mostly temperature) > part. > > Having a model for the aging the Algo can now model the temperature > dependence. However, a precondition for this were that the measurement sees > the temperature effects and that the ambient temperature is measured > independently. For that reason I expect the Algo will reduce its loop time > constant within the next time to make the temperature effect get through the > lowpass. Any bets on that? > > Best regards > Ulrich Bangert > > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert >> Gesendet: Donnerstag, 18. Juni 2009 08:29 >> An: 'Discussion of precise time and frequency measurement' >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >> >> >> Brian, >> >> >>> You may also want to search for HP An1279, it also goes over HP >>> smartclock operation, and look for a paper titled "the Global >>> Positioning System and HP SmartClock" by John A. Kusters. >>> >> In the meantime I have not only found these but also "Smart >> Clock: A New Time" by David Allan et al which shows that >> "Smart Clock" is originally a NIST invention & patent and >> explains very well how it works. Perhaps what I and You have >> seen is a direct consequence of applying the Smart Clock algorithm. >> >> Best regards >> Ulrich >> >> >> >>> -----Ursprungliche Nachricht----- >>> Von: time-nuts-bounces at febo.com >>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby >>> Gesendet: Donnerstag, 18. Juni 2009 01:51 >>> An: Discussion of precise time and frequency measurement >>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>> >>> >>> They do not talk about driving the frequency off, but they >>> warn to keep >>> the receiver locked the first 24 hours, so it can determine how the >>> oscillator ages. Its in the section on "holdover" (page 52 >>> of the PDF , >>> page 3-8 of the user guide). >>> >>> You may also want to search for HP An1279, it also goes over HP >>> smartclock operation, and look for a paper titled "the Global >>> Positioning System and HP SmartClock" by John A. Kusters. >>> >>> If you have a broadband connection, I can email you each >>> >> one, if that >> >>> will help. >>> >>> Brian >>> >>> Ulrich Bangert wrote: >>> >>>> Brian, >>>> >>>> thanks for your information! >>>> >>>> >>>> >>>>> algorithm. From what I read about the smart clock, it >>>>> >> takes 5 days >> >>>>> for it to complete its initial learning cycle and then its >>>>> >>>>> >>>> continuously >>>> >>>> >>>>> refining. >>>>> >>>>> >>>> Is that from the Z3801 manual, which I have available, or >>>> >>> do you have >>> >>>> any other in depth information source? >>>> >>>> Best regards >>>> Ulrich >>>> >>>> >>>> >>>>> -----Ursprungliche Nachricht----- >>>>> Von: time-nuts-bounces at febo.com >>>>> >> [mailto:time-nuts-bounces at febo.com] >> >>>>> Im Auftrag von Brian Kirby >>>>> Gesendet: Mittwoch, 17. Juni 2009 16:58 >>>>> An: Discussion of precise time and frequency measurement >>>>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>>>> >>>>> >>>>> Ulrich, >>>>> >>>>> I have two Z3801A and both of them act close to what you >>>>> >> describe >> >>>>> in the first 24 hours of power up. I believe its part of the >>>>> >>> disciplining >>> >>>>> algorithm. From what I read about the smart clock, it takes >>>>> 5 days for >>>>> it to complete its initial learning cycle and then its >>>>> >>> continuously >>> >>>>> refining. >>>>> >>>>> Brian >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts at febo.com >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>> and follow the instructions there. >>>>> >>>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts at febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From cfharris at erols.com Fri Jun 19 13:03:16 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 19 Jun 2009 09:03:16 -0400 Subject: [time-nuts] Bulova PCOXO... In-Reply-To: References: Message-ID: <4A3B8C94.7020204@erols.com> Oooh! Way to hijack a thread... on the first response too! All Bulova Accutrons can be adjusted to work with a 1.5V cell. If the specifications are to be believed, they are all supposed to work up to 1.7V when properly adjusted... They don't, though. The adjustment is not for the non watchmaker, though. It requires a 30x microscope, and a very steady hand. The Bulova test jig is helpful too. -Chuck Harris Mark Sims wrote: > Actually, that may be more of a problem than you think. These originally ran on a 1.35V mercury battery. A 1.5V > alkaline cell can overdrive the tuning fork causing the watch to run fast or not at all. > > The watch may be able to be adjusted to work with the modern battery or you need to use an "Accucell" battery. This > is a standard battery that is mounted in a machined brass holder with a dropping diode. > > ---------------------------------------- I still have one I bought for around $125 or 150 in Hawail in 1966. I'm > sure with a fresh battery it wud still work.. I have the see-thru model. > > > _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s > right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. > From rdarlington at gmail.com Fri Jun 19 13:13:46 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Fri, 19 Jun 2009 07:13:46 -0600 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B7EB4.9010802@rogers.com> References: <4A3B7EB4.9010802@rogers.com> Message-ID: I just bought an HP 3325A synthesizer/function generator that I really like (for some things anyway) in about that price range. What you get is probably dependent on what YOU need though. This thing is pretty limited but this particular one has the high voltage option so the output goes up to 40 volts up to 1MHz. It only goes to 20.99999999 Mhz (at up to 10V I think) but for 99% of what I do that's just fine. It has a 10MHz external reference which I hook to either an Rb osc or a Thunderbolt depending on what I'm doing. It's pretty neat to see all the digits match between the 3325A and the 5335A counter. Of course, that's being clocked by the same oscillator too. Also, I noticed on some signal generators, dropping the output down to a few mV distorts the signal. What I learned to do was send my signal out at about 1 volt ((RMS or p2p, doesn't matter) and go through a step attenuator to drop it back down so it comes out clean. -Bob, N3XKB On Fri, Jun 19, 2009 at 6:04 AM, Patrick wrote: > Hey everyone > > Sorry for the off topic post. I have received great advice in the past > with items for my little shop and I can't resist to ask again. > > I am thinking about buying a signal generator. I suspect that I will > mostly use it to inject low uV/mV signals into the amplification stages > of the laboratory instruments I service. > > Any feedback you have would be greatly appreciated-Patrick > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From cfharris at erols.com Fri Jun 19 13:15:04 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 19 Jun 2009 09:15:04 -0400 Subject: [time-nuts] HP5370A self test fault characteristics and diagnosis In-Reply-To: <4A3B47B8.2000706@xtra.co.nz> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> <4A3B426D.5080001@sonic.net> <4A3B47B8.2000706@xtra.co.nz> Message-ID: <4A3B8F58.9040405@erols.com> Bruce Griffiths wrote: > Bruce > > Rex wrote: >> Bruce, >> >> I've never seen you post a new thread as a response to an existing, >> unrelated thread, as you've done here. You are not the first to do >> this, but I thought you might be aware of these subtleties. >> > > I was being lazy. > How can you tell, looking at the message source I wasn't able to see any > indication of this? The references header points back to the post you replied to. In this case: <4ECC7583323F41D38EFD9C7AD619FE53 at athlon> -Chuck Harris From optomatic at rogers.com Fri Jun 19 13:38:46 2009 From: optomatic at rogers.com (optomatic at rogers.com) Date: Fri, 19 Jun 2009 09:38:46 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: References: <4A3B7EB4.9010802@rogers.com> Message-ID: <4A3B94E6.1000800@rogers.com> Hey Robert Great tip about the attenuator. I looked up some models on the internet and some look fairly expensive. I know that I will always be injecting low voltage signals, do you think it would be wise to buy a cheaper fixed attenuator, let's say 20dB?, and then just depend on the variable rate that the signal generator? Thanks-Patrick Robert Darlington wrote: > I just bought an HP 3325A synthesizer/function generator that I really like > (for some things anyway) in about that price range. What you get is > probably dependent on what YOU need though. This thing is pretty limited > but this particular one has the high voltage option so the output goes up to > 40 volts up to 1MHz. It only goes to 20.99999999 Mhz (at up to 10V I > think) but for 99% of what I do that's just fine. It has a 10MHz external > reference which I hook to either an Rb osc or a Thunderbolt depending on > what I'm doing. It's pretty neat to see all the digits match between the > 3325A and the 5335A counter. Of course, that's being clocked by the same > oscillator too. > > Also, I noticed on some signal generators, dropping the output down to a few > mV distorts the signal. What I learned to do was send my signal out at > about 1 volt ((RMS or p2p, doesn't matter) and go through a step attenuator > to drop it back down so it comes out clean. > > -Bob, N3XKB > > On Fri, Jun 19, 2009 at 6:04 AM, Patrick wrote: > > >> Hey everyone >> >> Sorry for the off topic post. I have received great advice in the past >> with items for my little shop and I can't resist to ask again. >> >> I am thinking about buying a signal generator. I suspect that I will >> mostly use it to inject low uV/mV signals into the amplification stages >> of the laboratory instruments I service. >> >> Any feedback you have would be greatly appreciated-Patrick >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From jmiles at pop.net Fri Jun 19 13:57:19 2009 From: jmiles at pop.net (John Miles) Date: Fri, 19 Jun 2009 06:57:19 -0700 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B94E6.1000800@rogers.com> Message-ID: No distortion at low levels will occur with any signal generator worth owning. Nothing from HP will do that. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of optomatic at rogers.com > Sent: Friday, June 19, 2009 6:39 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] OT favorite signal generator? > > > Hey Robert > > Great tip about the attenuator. > > I looked up some models on the internet and some look fairly expensive. > I know that I will always be injecting low voltage signals, do you think > it would be wise to buy a cheaper fixed attenuator, let's say 20dB?, and > then just depend on the variable rate that the signal generator? > > Thanks-Patrick > > Robert Darlington wrote: > > I just bought an HP 3325A synthesizer/function generator that I > really like > > (for some things anyway) in about that price range. What you get is > > probably dependent on what YOU need though. This thing is > pretty limited > > but this particular one has the high voltage option so the > output goes up to > > 40 volts up to 1MHz. It only goes to 20.99999999 Mhz (at up to 10V I > > think) but for 99% of what I do that's just fine. It has a > 10MHz external > > reference which I hook to either an Rb osc or a Thunderbolt depending on > > what I'm doing. It's pretty neat to see all the digits match > between the > > 3325A and the 5335A counter. Of course, that's being clocked > by the same > > oscillator too. > > > > Also, I noticed on some signal generators, dropping the output > down to a few > > mV distorts the signal. What I learned to do was send my signal out at > > about 1 volt ((RMS or p2p, doesn't matter) and go through a > step attenuator > > to drop it back down so it comes out clean. > > > > -Bob, N3XKB > > > > On Fri, Jun 19, 2009 at 6:04 AM, Patrick wrote: > > > > > >> Hey everyone > >> > >> Sorry for the off topic post. I have received great advice in the past > >> with items for my little shop and I can't resist to ask again. > >> > >> I am thinking about buying a signal generator. I suspect that I will > >> mostly use it to inject low uV/mV signals into the amplification stages > >> of the laboratory instruments I service. > >> > >> Any feedback you have would be greatly appreciated-Patrick > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts at febo.com > >> To unsubscribe, go to > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > >> > >> > From james.p.lux at jpl.nasa.gov Fri Jun 19 14:10:57 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Fri, 19 Jun 2009 07:10:57 -0700 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B7EB4.9010802@rogers.com> Message-ID: How accurate? What frequency range? What spectral performance (harmonics, spurs)? One thing to watch out for on testing with very low level signals is leakage out of the signal generator and into the unit under test via a path other than the coax. When we test deep space transponders at work at very low levels (-160dBm), we actually use a signal generator at a different frequency and multiply it up externally (partly that's also because historically, the signal generator didn't go high enough (7.15 GHz).. But when you use a modern signal gen that does work at 7GHz, you've got to be more careful). .. In any event, it doesn't take much to turn your careful and precise -160 into -159 or -161. On 6/19/09 5:04 AM, "Patrick" wrote: Hey everyone Sorry for the off topic post. I have received great advice in the past with items for my little shop and I can't resist to ask again. I am thinking about buying a signal generator. I suspect that I will mostly use it to inject low uV/mV signals into the amplification stages of the laboratory instruments I service. Any feedback you have would be greatly appreciated-Patrick _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From james.p.lux at jpl.nasa.gov Fri Jun 19 14:19:50 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Fri, 19 Jun 2009 07:19:50 -0700 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: Message-ID: We use a lot of 3325As in the lab at JPL (they used to have dozens of them at the deep space network, so there are lots of them around). Some have the rear panel option that puts out a sine wave up to 60MHz, which is fairly convenient. The settability with lots o' digits is nice (that's why they were used in DSN..).. Really a function generator with sine square triangle, and some modulation capability. You can also lock multiple 3325s together which is nice for generating things like I/Q signals with known errors in phase/amplitude, or with frequencies offset by 0.1 Hz (so it sweeps through all relative phases in 10 seconds), or clock signals with known skew (although something like an 8110 or it's newer brethren is nicer). They're not super quiet Depending on your needs, there might be better solutions. For a bit more money($600), you can get the TAPR Vector Network Analyzer from TenTec, which has a calibrated signal generator mode. In the few hundred dollar range, I've used a lot of eval boards from one source or another. Analog Devices has a whole bunch of DDS eval boards that take an external reference (always important for timenuts use) and with a small amount of work, you can calibrate them. National Semi has a whole bunch of PLL eval boards, if you need GHz kinds of frequencies. On 6/19/09 6:13 AM, "Robert Darlington" wrote: I just bought an HP 3325A synthesizer/function generator that I really like (for some things anyway) in about that price range. What you get is probably dependent on what YOU need though. This thing is pretty limited but this particular one has the high voltage option so the output goes up to 40 volts up to 1MHz. It only goes to 20.99999999 Mhz (at up to 10V I think) but for 99% of what I do that's just fine. It has a 10MHz external reference which I hook to either an Rb osc or a Thunderbolt depending on what I'm doing. It's pretty neat to see all the digits match between the 3325A and the 5335A counter. Of course, that's being clocked by the same oscillator too. Also, I noticed on some signal generators, dropping the output down to a few mV distorts the signal. What I learned to do was send my signal out at about 1 volt ((RMS or p2p, doesn't matter) and go through a step attenuator to drop it back down so it comes out clean. -Bob, N3XKB On Fri, Jun 19, 2009 at 6:04 AM, Patrick wrote: > Hey everyone > > Sorry for the off topic post. I have received great advice in the past > with items for my little shop and I can't resist to ask again. > > I am thinking about buying a signal generator. I suspect that I will > mostly use it to inject low uV/mV signals into the amplification stages > of the laboratory instruments I service. > > Any feedback you have would be greatly appreciated-Patrick > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From james.p.lux at jpl.nasa.gov Fri Jun 19 14:22:46 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Fri, 19 Jun 2009 07:22:46 -0700 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B94E6.1000800@rogers.com> Message-ID: On 6/19/09 6:38 AM, "optomatic at rogers.com" wrote: > Hey Robert > > Great tip about the attenuator. > > I looked up some models on the internet and some look fairly expensive. > I know that I will always be injecting low voltage signals, do you think > it would be wise to buy a cheaper fixed attenuator, let's say 20dB?, and > then just depend on the variable rate that the signal generator? > How precise does your level have to be? How stable? There are surplus attenuators available all over the place, some variable ones too. MiniCircuits has VAT-nn attenuators which are relatively inexpensive (not by "found it at a ham-fest 30 years ago" standards, though) Building your own attenuator using chip resistors is another possibility. From optomatic at rogers.com Fri Jun 19 14:41:41 2009 From: optomatic at rogers.com (Patrick) Date: Fri, 19 Jun 2009 10:41:41 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: References: Message-ID: <4A3BA3A5.1010805@rogers.com> Hi James Thanks for your feedback on this. My needs are probably very privative compared to those of the people on this list. I service a lot of the time without a schematic so I spend a lot of time figuring out how the circuit works. I was thinking that if I injected a signal with a known waveform I could follow it around the amplification circuits and such. My only real need is to create something that does not appear to already be there. For instance I don't see many triangle waves, if I produced one I could following it around with my oscilloscope. So in terms of frequency just a few hertz would do, heck even 1 would probably be fine. My only concern is that some of the circuits are high impedance and have low voltages. It might be a good idea if I could get down somewhere into the uV range. Thanks again!-Patrick Lux, James P wrote: > > On 6/19/09 6:38 AM, "optomatic at rogers.com" wrote: > > >> Hey Robert >> >> Great tip about the attenuator. >> >> I looked up some models on the internet and some look fairly expensive. >> I know that I will always be injecting low voltage signals, do you think >> it would be wise to buy a cheaper fixed attenuator, let's say 20dB?, and >> then just depend on the variable rate that the signal generator? >> >> > > How precise does your level have to be? How stable? > There are surplus attenuators available all over the place, some variable > ones too. > MiniCircuits has VAT-nn attenuators which are relatively inexpensive (not by > "found it at a ham-fest 30 years ago" standards, though) > > Building your own attenuator using chip resistors is another possibility. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From jra at febo.com Fri Jun 19 14:42:43 2009 From: jra at febo.com (John Ackermann N8UR) Date: Fri, 19 Jun 2009 10:42:43 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: References: Message-ID: <4A3BA3E3.8050404@febo.com> I took a look at the phase noise of a 3325B and as Jim said, the phase noise is not great -- about -60 dBc at 1 Hz offset. An external reference cleans up the close in (<10 Hz) signal, but beyond about 10 Hz the synthesizer noice drowns out the reference; from the noise from 10 Hz to about 3 kHz is about -115 dBc, then it drops off to a floor of around -135 dBc at 100 kHz. Some plots are at http://www.febo.com/pages/hp3325b/ That said, they are awfully nice boxes for audio and low HF use. John ---- Lux, James P wrote: > We use a lot of 3325As in the lab at JPL (they used to have dozens of them at the deep space network, so there are lots of them around). Some have the rear panel option that puts out a sine wave up to 60MHz, which is fairly convenient. > The settability with lots o' digits is nice (that's why they were used in DSN..).. Really a function generator with sine square triangle, and some modulation capability. You can also lock multiple 3325s together which is nice for generating things like I/Q signals with known errors in phase/amplitude, or with frequencies offset by 0.1 Hz (so it sweeps through all relative phases in 10 seconds), or clock signals with known skew (although something like an 8110 or it's newer brethren is nicer). > They're not super quiet > > Depending on your needs, there might be better solutions. For a bit more money($600), you can get the TAPR Vector Network Analyzer from TenTec, which has a calibrated signal generator mode. In the few hundred dollar range, I've used a lot of eval boards from one source or another. Analog Devices has a whole bunch of DDS eval boards that take an external reference (always important for timenuts use) and with a small amount of work, you can calibrate them. National Semi has a whole bunch of PLL eval boards, if you need GHz kinds of frequencies. > > > On 6/19/09 6:13 AM, "Robert Darlington" wrote: > > I just bought an HP 3325A synthesizer/function generator that I really like > (for some things anyway) in about that price range. What you get is > probably dependent on what YOU need though. This thing is pretty limited > but this particular one has the high voltage option so the output goes up to > 40 volts up to 1MHz. It only goes to 20.99999999 Mhz (at up to 10V I > think) but for 99% of what I do that's just fine. It has a 10MHz external > reference which I hook to either an Rb osc or a Thunderbolt depending on > what I'm doing. It's pretty neat to see all the digits match between the > 3325A and the 5335A counter. Of course, that's being clocked by the same > oscillator too. > > Also, I noticed on some signal generators, dropping the output down to a few > mV distorts the signal. What I learned to do was send my signal out at > about 1 volt ((RMS or p2p, doesn't matter) and go through a step attenuator > to drop it back down so it comes out clean. > > -Bob, N3XKB > > On Fri, Jun 19, 2009 at 6:04 AM, Patrick wrote: > >> Hey everyone >> >> Sorry for the off topic post. I have received great advice in the past >> with items for my little shop and I can't resist to ask again. >> >> I am thinking about buying a signal generator. I suspect that I will >> mostly use it to inject low uV/mV signals into the amplification stages >> of the laboratory instruments I service. >> >> Any feedback you have would be greatly appreciated-Patrick >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From frledda at verizon.net Fri Jun 19 14:38:04 2009 From: frledda at verizon.net (Francesco Ledda) Date: Fri, 19 Jun 2009 09:38:04 -0500 Subject: [time-nuts] Z3805 initial behavior after power up revised In-Reply-To: <4A3B8B8B.9090701@rubidium.dyndns.org> Message-ID: Variation due to environment are deterministic and are nor part of aging. Ageing needs to measured in conditions that remove ambient induced perturbations. I used to put crystal oscillators in high quality environmental chambers that kept temp, humidity and pressure constant and measure the ageing. There are tricks that can be done to increase the aging rate, so that we did not have to wait 20 years ;) We know that ageing happens, but the direction of ageing cannot be determined. A coin toss can yield face or tail. If the coin is perfect, the distribution will be uniform. If a face is 1 and a tail is -1, we can add successive tosses and track the total number. Even is the distribution of tosses is uniform, the sum will walk away from 0 (random walk),cameback to 0 and then move away from 0 again. This is a good way to model and explain ageing. Nature is perfect, but things do not follow our math perfectly. A better simulation would include a "leaky integral". The statistical analysis of ageing is tricky, since ageing doeas have a statistical mean, and therefore standard deviation cannot be used. This discussion brings lots of good memories back. The good old days when SONET synchronization was a new thing, and we were creating new technology. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Magnus Danielson Sent: Friday, June 19, 2009 7:59 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Z3805 initial behaviour after power up revised Francesco Ledda wrote: > Aging cannot be predicted! If it could be predicetd, there would be no > aging. > Not entierly true. Even with a perfectly known aging, only a few oscillators would bother to estimate and correct it. This can never be perfectly done anyway, and there is only so many things you can bring into the model while keeping it economical. There is fairly good clues around. If all was included and handled, it would reduce the effects. Cheers, Magnus > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Ulrich Bangert > Sent: Thursday, June 18, 2009 3:04 AM > To: 'Discussion of precise time and frequency measurement' > Subject: [time-nuts] Z3805 initial behaviour after power up revised > > > Gents, > > one of the papers suggested by Brian says: > ------------------------------------------- > SmartClock monitors the frequency control variable of the internal > oscillator while it is locked to the external reference. This gives a > measure of the frequency difference between the internal oscillator, if it > is free-running, and the external reference over time. The resulting > measurements include the effects of random noise in the oscillator, the > measurement circuitry, and any noise in the external reference as well as > any aging and environmental effects in the oscillator. From this > information, SmartClock makes a continuous prediction of clock error over > time. > ------------------------------------------- > > The big question is: If the EFC signal includes this all information, how > does the algo manage to extract the individual informations? After having a > look at the PPS TI and the EFC of my Z3805 I am beginning to get a clue of > it (the quirks on the EFC signal heve been removed): > > The SmartClock algo seems to set the loop time constants to a large value in > the beginning. In other words: It measures the overall oscillator frequency > influencing effects with a lowpass filter applied that has a very low cutoff > frequency. Only effects which's frequency are sufficient lower then the > cutoff pass the filter. Seems as if the SmartClock uses this filter setting > to exclude any noise related effect and any environmental effect and make > the measurement see ONLY the oscillator's aging. > > Once it has learned enough about the aging process it will be able to > predict aging. Having reached this state it will be able to apply his > knowledge about aging to further TI measurements and subtract the "aging > part" of it, leaving mostly the environmental (which is mostly temperature) > part. > > Having a model for the aging the Algo can now model the temperature > dependence. However, a precondition for this were that the measurement sees > the temperature effects and that the ambient temperature is measured > independently. For that reason I expect the Algo will reduce its loop time > constant within the next time to make the temperature effect get through the > lowpass. Any bets on that? > > Best regards > Ulrich Bangert > > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert >> Gesendet: Donnerstag, 18. Juni 2009 08:29 >> An: 'Discussion of precise time and frequency measurement' >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >> >> >> Brian, >> >> >>> You may also want to search for HP An1279, it also goes over HP >>> smartclock operation, and look for a paper titled "the Global >>> Positioning System and HP SmartClock" by John A. Kusters. >>> >> In the meantime I have not only found these but also "Smart >> Clock: A New Time" by David Allan et al which shows that >> "Smart Clock" is originally a NIST invention & patent and >> explains very well how it works. Perhaps what I and You have >> seen is a direct consequence of applying the Smart Clock algorithm. >> >> Best regards >> Ulrich >> >> >> >>> -----Ursprungliche Nachricht----- >>> Von: time-nuts-bounces at febo.com >>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby >>> Gesendet: Donnerstag, 18. Juni 2009 01:51 >>> An: Discussion of precise time and frequency measurement >>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>> >>> >>> They do not talk about driving the frequency off, but they >>> warn to keep >>> the receiver locked the first 24 hours, so it can determine how the >>> oscillator ages. Its in the section on "holdover" (page 52 >>> of the PDF , >>> page 3-8 of the user guide). >>> >>> You may also want to search for HP An1279, it also goes over HP >>> smartclock operation, and look for a paper titled "the Global >>> Positioning System and HP SmartClock" by John A. Kusters. >>> >>> If you have a broadband connection, I can email you each >>> >> one, if that >> >>> will help. >>> >>> Brian >>> >>> Ulrich Bangert wrote: >>> >>>> Brian, >>>> >>>> thanks for your information! >>>> >>>> >>>> >>>>> algorithm. From what I read about the smart clock, it >>>>> >> takes 5 days >> >>>>> for it to complete its initial learning cycle and then its >>>>> >>>>> >>>> continuously >>>> >>>> >>>>> refining. >>>>> >>>>> >>>> Is that from the Z3801 manual, which I have available, or >>>> >>> do you have >>> >>>> any other in depth information source? >>>> >>>> Best regards >>>> Ulrich >>>> >>>> >>>> >>>>> -----Ursprungliche Nachricht----- >>>>> Von: time-nuts-bounces at febo.com >>>>> >> [mailto:time-nuts-bounces at febo.com] >> >>>>> Im Auftrag von Brian Kirby >>>>> Gesendet: Mittwoch, 17. Juni 2009 16:58 >>>>> An: Discussion of precise time and frequency measurement >>>>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>>>> >>>>> >>>>> Ulrich, >>>>> >>>>> I have two Z3801A and both of them act close to what you >>>>> >> describe >> >>>>> in the first 24 hours of power up. I believe its part of the >>>>> >>> disciplining >>> >>>>> algorithm. From what I read about the smart clock, it takes >>>>> 5 days for >>>>> it to complete its initial learning cycle and then its >>>>> >>> continuously >>> >>>>> refining. >>>>> >>>>> Brian >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts at febo.com >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>> and follow the instructions there. >>>>> >>>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts at febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From stanw1le at verizon.net Fri Jun 19 14:36:27 2009 From: stanw1le at verizon.net (Stan W1LE) Date: Fri, 19 Jun 2009 10:36:27 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: References: Message-ID: <4A3BA26B.6000305@verizon.net> Hello Pat, Ebay could be your friend in locating a signal generator, as well as researching availability and pricing. My perspective is that Ebay is the big flea market in the ether and you do not know what you got, till you get it on your test bench and exercise it. Bid accordingly, most dealers are simply junk/scrap dealers who buy the stuff by the pallet load and hope for a quick sale. There are some used equipment dealers that will provide calibration and a guarantee. I have had decent luck selectively bidding on older obsolete HP/Agilent/Fluke/TEK test gear. Many manuals and other documents are available at the HP/Agilent website, a tremendous resource. Consider buying a second of a unit for a parts unit. Get them while you can. The stuff I buy is clearly obsolete and not logistically supported by the manufacturer. I am happy with 80's and 90's vintage commercial test equipment. Stan, W1LE Cape Cod From peterawson at earthlink.net Fri Jun 19 15:27:39 2009 From: peterawson at earthlink.net (Pete) Date: Fri, 19 Jun 2009 09:27:39 -0600 Subject: [time-nuts] OT favorite signal generator? References: <4A3BA3A5.1010805@rogers.com> Message-ID: <3931CD34BF8C41A9B52FC0FD3D5DD2B5@BASE1> Patrick, If signal tracing in a "mystery" circuit is important, I would look for a generator with external FM input. This feature is common in upscale units. Using a basic audio function generator on the FM input, you can supply 2 tone FM, switching at 1 or 2Hz which is easy to identify in the device you're testing. Pete Rawson From rdarlington at gmail.com Fri Jun 19 15:32:41 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Fri, 19 Jun 2009 09:32:41 -0600 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B94E6.1000800@rogers.com> References: <4A3B7EB4.9010802@rogers.com> <4A3B94E6.1000800@rogers.com> Message-ID: Patrick, Using a large fixed attenuator should work fine. I learned the attenuator trick when dealing with some variable gain amp chips from Analog. Instead of varying the gain, they run at some fixed level that produces a clean output, and vary the attenuation level to prevent non-linear effects and distortion. HP might be doing this, then again, maybe not. Some of my instruments are very sensitive to input overloading and I just got in the habit of using a step attenuator between the signal source and the VNA or spectrum analyzer, or what have you. It helps to prevent stupid mistakes that seem to happen at all the wrong times. As John Miles said, no HP signal generator should produce a distorted output at low level. My Tektronix does! -Bob On Fri, Jun 19, 2009 at 7:38 AM, wrote: > Hey Robert > > Great tip about the attenuator. > > I looked up some models on the internet and some look fairly expensive. I > know that I will always be injecting low voltage signals, do you think it > would be wise to buy a cheaper fixed attenuator, let's say 20dB?, and then > just depend on the variable rate that the signal generator? > > Thanks-Patrick > > > Robert Darlington wrote: > >> I just bought an HP 3325A synthesizer/function generator that I really >> like >> (for some things anyway) in about that price range. What you get is >> probably dependent on what YOU need though. This thing is pretty limited >> but this particular one has the high voltage option so the output goes up >> to >> 40 volts up to 1MHz. It only goes to 20.99999999 Mhz (at up to 10V I >> think) but for 99% of what I do that's just fine. It has a 10MHz external >> reference which I hook to either an Rb osc or a Thunderbolt depending on >> what I'm doing. It's pretty neat to see all the digits match between the >> 3325A and the 5335A counter. Of course, that's being clocked by the same >> oscillator too. >> >> Also, I noticed on some signal generators, dropping the output down to a >> few >> mV distorts the signal. What I learned to do was send my signal out at >> about 1 volt ((RMS or p2p, doesn't matter) and go through a step >> attenuator >> to drop it back down so it comes out clean. >> >> -Bob, N3XKB >> >> On Fri, Jun 19, 2009 at 6:04 AM, Patrick wrote: >> >> >> >>> Hey everyone >>> >>> Sorry for the off topic post. I have received great advice in the past >>> with items for my little shop and I can't resist to ask again. >>> >>> I am thinking about buying a signal generator. I suspect that I will >>> mostly use it to inject low uV/mV signals into the amplification stages >>> of the laboratory instruments I service. >>> >>> Any feedback you have would be greatly appreciated-Patrick >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From cfharris at erols.com Fri Jun 19 15:48:35 2009 From: cfharris at erols.com (Chuck Harris) Date: Fri, 19 Jun 2009 11:48:35 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: References: <4A3B7EB4.9010802@rogers.com> <4A3B94E6.1000800@rogers.com> Message-ID: <4A3BB353.0@erols.com> Robert Darlington wrote: > > As John Miles said, no HP signal generator should produce a distorted output > at low level. My Tektronix does! It depends on how they lower the signal level. If the signal level is lowered using a traditional attenuator, the distortion will be unchanged, but if the signal level is lowered by biasing a pin diode attenuator, or by changing the bias on a gain stage, it will change the distortion all over the place. Basically, if there is a pot to adjust the signal level, you can expect the distortion to change too. If there is a selector switch like mechanism, the distortion will probably not be affected. -Chuck Harris From brooke at pacific.net Fri Jun 19 15:52:29 2009 From: brooke at pacific.net (Brooke Clarke) Date: Fri, 19 Jun 2009 08:52:29 -0700 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B7EB4.9010802@rogers.com> References: <4A3B7EB4.9010802@rogers.com> Message-ID: <4A3BB43D.9050601@pacific.net> Hi Patrick: There are a bunch of signal sources that could be used. The rack sized HP signal generators that weigh 50+ pounds were designed to have very low phase noise and although now many years old are still very good for that. The HP 3325() is the only signal generator that has adjustable amplitude that's calibrated to a small fraction of a dB. They still are the specified instrument for amplitude calibration of many other pieces of lab equipment and there is no newer instrument to replace them. They don't have good specs in the frequency domain. The HP 8648() series are reasonably small and light synthesized signal generators. I got the 8648A Option 1EP which is specific for pager testing and includes many modulation enhancements. The prior versions of the 8648 did not have good enough specs to test pagers. http://www.prc68.com/I/HP8648.shtml A problem with injecting a signal into operating equipment is you may burn out the signal generator. For example just touching a DC point feeds a step change back into the sig gen. So it's good to have a series resistor and blocking cap to protect the sig gen. You might be able to use a probe that generates something like narrow pulses at an audio rate as a universal signal source. Have Fun, Brooke Clarke http://www.prc68.com Patrick wrote: > Hey everyone > > Sorry for the off topic post. I have received great advice in the past > with items for my little shop and I can't resist to ask again. > > I am thinking about buying a signal generator. I suspect that I will > mostly use it to inject low uV/mV signals into the amplification stages > of the laboratory instruments I service. > > Any feedback you have would be greatly appreciated-Patrick > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From frledda at verizon.net Fri Jun 19 15:57:17 2009 From: frledda at verizon.net (Francesco Ledda) Date: Fri, 19 Jun 2009 10:57:17 -0500 Subject: [time-nuts] Z3805 initial behavior after power up revised In-Reply-To: Message-ID: Correction... -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Francesco Ledda Sent: Friday, June 19, 2009 9:38 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Z3805 initial behavior after power up revised Variation due to environment are deterministic and are nor part of aging. Ageing needs to measured in conditions that remove ambient induced perturbations. I used to put crystal oscillators in high quality environmental chambers that kept temp, humidity and pressure constant and measure the ageing. There are tricks that can be done to increase the aging rate, so that we did not have to wait 20 years ;) We know that ageing happens, but the direction of ageing cannot be determined. A coin toss can yield face or tail. If the coin is perfect, the distribution will be uniform. If a face is 1 and a tail is -1, we can add successive tosses and track the total number. Even is the distribution of tosses is uniform, the sum will walk away from 0 (random walk),cameback to 0 and then move away from 0 again. This is a good way to model and explain ageing. Nature is perfect, but things do not follow our math perfectly. A better simulation would include a "leaky integral". The statistical analysis of ageing is tricky, since ageing doeas have NOT a statistical mean, and therefore standard deviation cannot be used. This discussion brings lots of good memories back. The good old days when SONET synchronization was a new thing, and we were creating new technology. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Magnus Danielson Sent: Friday, June 19, 2009 7:59 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Z3805 initial behaviour after power up revised Francesco Ledda wrote: > Aging cannot be predicted! If it could be predicetd, there would be no > aging. > Not entierly true. Even with a perfectly known aging, only a few oscillators would bother to estimate and correct it. This can never be perfectly done anyway, and there is only so many things you can bring into the model while keeping it economical. There is fairly good clues around. If all was included and handled, it would reduce the effects. Cheers, Magnus > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Ulrich Bangert > Sent: Thursday, June 18, 2009 3:04 AM > To: 'Discussion of precise time and frequency measurement' > Subject: [time-nuts] Z3805 initial behaviour after power up revised > > > Gents, > > one of the papers suggested by Brian says: > ------------------------------------------- > SmartClock monitors the frequency control variable of the internal > oscillator while it is locked to the external reference. This gives a > measure of the frequency difference between the internal oscillator, if it > is free-running, and the external reference over time. The resulting > measurements include the effects of random noise in the oscillator, the > measurement circuitry, and any noise in the external reference as well as > any aging and environmental effects in the oscillator. From this > information, SmartClock makes a continuous prediction of clock error over > time. > ------------------------------------------- > > The big question is: If the EFC signal includes this all information, how > does the algo manage to extract the individual informations? After having a > look at the PPS TI and the EFC of my Z3805 I am beginning to get a clue of > it (the quirks on the EFC signal heve been removed): > > The SmartClock algo seems to set the loop time constants to a large value in > the beginning. In other words: It measures the overall oscillator frequency > influencing effects with a lowpass filter applied that has a very low cutoff > frequency. Only effects which's frequency are sufficient lower then the > cutoff pass the filter. Seems as if the SmartClock uses this filter setting > to exclude any noise related effect and any environmental effect and make > the measurement see ONLY the oscillator's aging. > > Once it has learned enough about the aging process it will be able to > predict aging. Having reached this state it will be able to apply his > knowledge about aging to further TI measurements and subtract the "aging > part" of it, leaving mostly the environmental (which is mostly temperature) > part. > > Having a model for the aging the Algo can now model the temperature > dependence. However, a precondition for this were that the measurement sees > the temperature effects and that the ambient temperature is measured > independently. For that reason I expect the Algo will reduce its loop time > constant within the next time to make the temperature effect get through the > lowpass. Any bets on that? > > Best regards > Ulrich Bangert > > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert >> Gesendet: Donnerstag, 18. Juni 2009 08:29 >> An: 'Discussion of precise time and frequency measurement' >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >> >> >> Brian, >> >> >>> You may also want to search for HP An1279, it also goes over HP >>> smartclock operation, and look for a paper titled "the Global >>> Positioning System and HP SmartClock" by John A. Kusters. >>> >> In the meantime I have not only found these but also "Smart >> Clock: A New Time" by David Allan et al which shows that >> "Smart Clock" is originally a NIST invention & patent and >> explains very well how it works. Perhaps what I and You have >> seen is a direct consequence of applying the Smart Clock algorithm. >> >> Best regards >> Ulrich >> >> >> >>> -----Ursprungliche Nachricht----- >>> Von: time-nuts-bounces at febo.com >>> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby >>> Gesendet: Donnerstag, 18. Juni 2009 01:51 >>> An: Discussion of precise time and frequency measurement >>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>> >>> >>> They do not talk about driving the frequency off, but they >>> warn to keep >>> the receiver locked the first 24 hours, so it can determine how the >>> oscillator ages. Its in the section on "holdover" (page 52 >>> of the PDF , >>> page 3-8 of the user guide). >>> >>> You may also want to search for HP An1279, it also goes over HP >>> smartclock operation, and look for a paper titled "the Global >>> Positioning System and HP SmartClock" by John A. Kusters. >>> >>> If you have a broadband connection, I can email you each >>> >> one, if that >> >>> will help. >>> >>> Brian >>> >>> Ulrich Bangert wrote: >>> >>>> Brian, >>>> >>>> thanks for your information! >>>> >>>> >>>> >>>>> algorithm. From what I read about the smart clock, it >>>>> >> takes 5 days >> >>>>> for it to complete its initial learning cycle and then its >>>>> >>>>> >>>> continuously >>>> >>>> >>>>> refining. >>>>> >>>>> >>>> Is that from the Z3801 manual, which I have available, or >>>> >>> do you have >>> >>>> any other in depth information source? >>>> >>>> Best regards >>>> Ulrich >>>> >>>> >>>> >>>>> -----Ursprungliche Nachricht----- >>>>> Von: time-nuts-bounces at febo.com >>>>> >> [mailto:time-nuts-bounces at febo.com] >> >>>>> Im Auftrag von Brian Kirby >>>>> Gesendet: Mittwoch, 17. Juni 2009 16:58 >>>>> An: Discussion of precise time and frequency measurement >>>>> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up >>>>> >>>>> >>>>> Ulrich, >>>>> >>>>> I have two Z3801A and both of them act close to what you >>>>> >> describe >> >>>>> in the first 24 hours of power up. I believe its part of the >>>>> >>> disciplining >>> >>>>> algorithm. From what I read about the smart clock, it takes >>>>> 5 days for >>>>> it to complete its initial learning cycle and then its >>>>> >>> continuously >>> >>>>> refining. >>>>> >>>>> Brian >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts at febo.com >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>> and follow the instructions there. >>>>> >>>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts at febo.com >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From w9ac at arrl.net Fri Jun 19 16:38:17 2009 From: w9ac at arrl.net (Paul Christensen) Date: Fri, 19 Jun 2009 12:38:17 -0400 Subject: [time-nuts] Thunderbolt - any negatives ? References: Message-ID: > "The other issue is noise from a switcher." And be mindful that some frequency-standard devices contain integrated DC-DC switching converters -- like my HP 58540A GPS-DO. The noise from the HP DC converters was spraying RFI every 100 kHz or so on the HF bands. After trying various RFI abatement measures, including additional bypass C and toroid-wound #31 ferrite material, my solution was scrap the entire PS board and bring in clean power from a triple-output linear supply made by Power-One. There's no switch-mode component anywhere in the path of my GPS-DO. I love switch-mode devices for their light weight and package density; I hate them for their propensity to generate RFI and at least historically, their abysmal long-term reliability. That said, I do believe that recent SMPS product is significantly more reliable than those manufactured 10+ years ago. Paul, W9AC From rexa at sonic.net Fri Jun 19 18:40:20 2009 From: rexa at sonic.net (Rex) Date: Fri, 19 Jun 2009 11:40:20 -0700 Subject: [time-nuts] My HP5370A performance Message-ID: <4A3BDB94.1040301@sonic.net> John Miles wrote: >The procedure Bruce was describing is basically the jitter test from the >manual, at http://cp.literature.agilent.com/litweb/pdf/05370-90031.pdf (this >is actually the same copy that David Kirkby scanned a few years ago, hosted >by Agilent.) Follow the directions on page 3-11 and 3-12, and post the >results, especially from step 15. This jitter figure is usually well under >50 ps in a 5370 that's working properly. > >-- john, KE5FX > > > > Bruce and John, Thanks for pointing me back to these operator checks. I ran through the procedures this morning and nothing seems out of spec. I guess I just had unrealistic expectations about how stable the displays should be while looking at that counter's own clock. Here's my results from the Operators Checks on 3-11, 3-12: 1 - 12. Setup 13. Initial TI function: 99.59 to 99.68 nS 14. Sample 100, 99.605 to 99.618 1000, 99.603 to 99.612 10K, 99.6xx x 100K, 99.6xx x 15. STD DEV, +-TI SS 100, 18.x to 24.x pS MIN, -0.45 to -0.53 MAX, -0.3x 16. DSP REF 000 SET REF 99.613 nS CLR REF 00.000 DSP EVTS 100 17. MEAN, 1, +-TI : -0.37 to -0.47 nS PERIOD COMPLEMENT ok 18. TRIG LEV ok 19. FREQ .01S 9.999 999 9xx to 10.000 000 0x .1S 9.999 999 99x x to 10.000 000 01x 1S 9.999 999 999 xx to 10.000 000 001 x 20. PERIOD 99.9X to 100.00 nS 21. Start/Stop Output ok I guess all of that is in specification. Any comments appreciated. -Rex From magnus at rubidium.dyndns.org Fri Jun 19 19:00:12 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 19 Jun 2009 21:00:12 +0200 Subject: [time-nuts] My HP5370A performance In-Reply-To: <4A3BDB94.1040301@sonic.net> References: <4A3BDB94.1040301@sonic.net> Message-ID: <4A3BE03C.3040905@rubidium.dyndns.org> Rex wrote: > John Miles wrote: > >> The procedure Bruce was describing is basically the jitter test from the >> manual, at >> http://cp.literature.agilent.com/litweb/pdf/05370-90031.pdf (this >> is actually the same copy that David Kirkby scanned a few years ago, >> hosted >> by Agilent.) Follow the directions on page 3-11 and 3-12, and post the >> results, especially from step 15. This jitter figure is usually well >> under >> 50 ps in a 5370 that's working properly. >> >> -- john, KE5FX >> >> >> >> > > Bruce and John, > > Thanks for pointing me back to these operator checks. I ran through > the procedures this morning and nothing seems out of spec. I guess I > just had unrealistic expectations about how stable the displays should > be while looking at that counter's own clock. > > Here's my results from the Operators Checks on 3-11, 3-12: > > 1 - 12. Setup > > 13. Initial TI function: 99.59 to 99.68 nS > > 14. Sample 100, 99.605 to 99.618 > 1000, 99.603 to 99.612 > 10K, 99.6xx x > 100K, 99.6xx x > > 15. STD DEV, +-TI > SS 100, 18.x to 24.x pS > MIN, -0.45 to -0.53 > MAX, -0.3x > > 16. DSP REF 000 > SET REF 99.613 nS > CLR REF 00.000 > DSP EVTS 100 > > 17. MEAN, 1, +-TI : -0.37 to -0.47 nS > PERIOD COMPLEMENT ok > > 18. TRIG LEV ok > > 19. FREQ .01S 9.999 999 9xx to 10.000 000 0x > .1S 9.999 999 99x x to 10.000 000 01x > 1S 9.999 999 999 xx to 10.000 000 001 x > > 20. PERIOD 99.9X to 100.00 nS > > 21. Start/Stop Output ok > > > I guess all of that is in specification. Any comments appreciated. If you have a spectrum analyzer, take a look at the 10 MHz output. If you see 5 MHz and overtones, then there is a simple mod for you to do, to remove them. Also, if you feel up for it, check the multiplier chain as indicated in the manual. The higher resolution you have, the more digits will be affected by a noise source... Cheers, Magnus From peterawson at earthlink.net Fri Jun 19 19:26:41 2009 From: peterawson at earthlink.net (Pete) Date: Fri, 19 Jun 2009 13:26:41 -0600 Subject: [time-nuts] My HP5370A performance References: <4A3BDB94.1040301@sonic.net> Message-ID: Rex, Your 5370A is performing well. While it's possible to use the adjustment procedure to gain a few ps better readings, the result is largely an illusion & won't produce better results with real world signals. If you choose to wander into the adjustment procedures, be sure to have the required test equipment at hand. Correctly adjusting the 5370A is NOT an exercise to take lightly & can result in poorer results than your unit is displaying. The other caution about this box is the adjustments are often interactive & may require many iterations to get right. As for stable readings in the last 2 or 3 digits, if you compute the influence of the specified 300uV of input referred noise, you'll see that the variations you're observing are probably smaller than the noise voltage suggests. All this would be easier to deal with if the data output capability of this box was simple, but it's not & that's too bad. Despite these issues, the 5370A/B is still the highest time resolution counter from H-P/Agilent. Pete Rawson From magnus at rubidium.dyndns.org Fri Jun 19 20:30:11 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 19 Jun 2009 22:30:11 +0200 Subject: [time-nuts] [Fwd: GPS 256 week rollover may be causing problems for some GPS receivers] Message-ID: <4A3BF553.20205@rubidium.dyndns.org> Fellow time-nuts, Have any of you seen the reported problems? Cheers, Magnus -------------- next part -------------- An embedded message was scrubbed... From: "TIS-PF-NISWS" Subject: GPS 256 week rollover may be causing problems for some GPS receivers Date: Fri, 19 Jun 2009 14:36:05 -0400 Size: 5678 URL: From imp at bsdimp.com Fri Jun 19 20:34:48 2009 From: imp at bsdimp.com (M. Warner Losh) Date: Fri, 19 Jun 2009 14:34:48 -0600 (MDT) Subject: [time-nuts] [Fwd: GPS 256 week rollover may be causing problems for some GPS receivers] In-Reply-To: <4A3BF553.20205@rubidium.dyndns.org> References: <4A3BF553.20205@rubidium.dyndns.org> Message-ID: <20090619.143448.2102305600.imp@bsdimp.com> In message: <4A3BF553.20205 at rubidium.dyndns.org> Magnus Danielson writes: : Have any of you seen the reported problems? "These counts started at 0 roughly at midnight UTC 6 Jan 1980" What does "roughly" mean here in this context? Warner From phk at phk.freebsd.dk Fri Jun 19 20:41:20 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 19 Jun 2009 20:41:20 +0000 Subject: [time-nuts] [Fwd: GPS 256 week rollover may be causing problems for some GPS receivers] In-Reply-To: Your message of "Fri, 19 Jun 2009 14:34:48 CST." <20090619.143448.2102305600.imp@bsdimp.com> Message-ID: <4813.1245444080@critter.freebsd.dk> In message <20090619.143448.2102305600.imp at bsdimp.com>, "M. Warner Losh" writes : >In message: <4A3BF553.20205 at rubidium.dyndns.org> > Magnus Danielson writes: >: Have any of you seen the reported problems? > >"These counts started at 0 roughly at midnight UTC 6 Jan 1980" > >What does "roughly" mean here in this context? That the we have leap seconds. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From magnus at rubidium.dyndns.org Fri Jun 19 20:41:03 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 19 Jun 2009 22:41:03 +0200 Subject: [time-nuts] [Fwd: GPS 256 week rollover may be causing problems for some GPS receivers] In-Reply-To: <20090619.143448.2102305600.imp@bsdimp.com> References: <4A3BF553.20205@rubidium.dyndns.org> <20090619.143448.2102305600.imp@bsdimp.com> Message-ID: <4A3BF7DF.5080408@rubidium.dyndns.org> M. Warner Losh skrev: > In message: <4A3BF553.20205 at rubidium.dyndns.org> > Magnus Danielson writes: > : Have any of you seen the reported problems? > > "These counts started at 0 roughly at midnight UTC 6 Jan 1980" > > What does "roughly" mean here in this context? Well, GPS and UTC was aligned at that time, maybe that was what helped confusing the text? Cheers, Magnus From magnus at rubidium.dyndns.org Fri Jun 19 21:21:47 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 19 Jun 2009 23:21:47 +0200 Subject: [time-nuts] [Fwd: GPS 256 week rollover may be causing problems for some GPS receivers] In-Reply-To: <4813.1245444080@critter.freebsd.dk> References: <4813.1245444080@critter.freebsd.dk> Message-ID: <4A3C016B.1010409@rubidium.dyndns.org> Poul-Henning Kamp skrev: > In message <20090619.143448.2102305600.imp at bsdimp.com>, "M. Warner Losh" writes > : >> In message: <4A3BF553.20205 at rubidium.dyndns.org> >> Magnus Danielson writes: >> : Have any of you seen the reported problems? >> >> "These counts started at 0 roughly at midnight UTC 6 Jan 1980" >> >> What does "roughly" mean here in this context? > > That the we have leap seconds. Doesn't affect GPS week rollovers, they occur in GPS time, which was coordinated with UTC at midnight 1980-01-06. So it was fairly exact, as it was defined to be coordinated. Cheers, Magnus From xde-l2g3 at myamail.com Fri Jun 19 21:24:20 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Fri, 19 Jun 2009 18:24:20 -0300 Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: > And be mindful that some frequency-standard devices contain > integrated DC-DC switching converters - like my HP 58540A GPS-DO. > The noise from the HP DC converters was spraying RFI every 100 kHz > or so on the HF bands. After trying various RFI abatement > measures, including additional bypass C and toroid-wound #31 > ferrite material, my solution was scrap the entire PS board and > bring in clean power from a triple-output linear supply made by > Power-One. There's no switch-mode component anywhere in the path > of my GPS-DO. I'm having the opposite problem. The linear supply in my HP 53310A Modulation Domain Analyzer spews out a huge magnetic field that completely disupts any nearby equipment. For example, it causes a fuzzy trace and triggering problems on TEK 2467B scopes, which makes the scope unusable for low-level work. No amount of shielding has helped. I'm seriously considering making the 53310A DC power section into a switcher. I have developed some techniques that greatly reduce crosstalk by mounting circuits on their own grounded platform. These have a minimum number of connections to the main system ground, and are chosen to minimize switching currents from flowing on the main system ground. I put a brief description of the PST Prototype Platform on my web site at http://pstca.com/spice/pstpp/pstpp.htm Another technique that can help is adding an active filter to the output of the power supply. These can be very effective, but there are a number of approaches that are well-publicized that don't work very well. There is more analysis here: http://pstca.com/spice/ripple/ripple.htm Finally, Linear Technology supplies Low Noise Switching Regulators that can give ripple values of less than 100uV, which is comparable to or less than many linear regulators. If interested, see the links in the above url. Noise can be a tricky problem, but the above information might give some ideas to help tame it. Mike From imp at bsdimp.com Fri Jun 19 22:54:08 2009 From: imp at bsdimp.com (M. Warner Losh) Date: Fri, 19 Jun 2009 16:54:08 -0600 (MDT) Subject: [time-nuts] [Fwd: GPS 256 week rollover may be causing problems for some GPS receivers] In-Reply-To: <4813.1245444080@critter.freebsd.dk> References: <20090619.143448.2102305600.imp@bsdimp.com> <4813.1245444080@critter.freebsd.dk> Message-ID: <20090619.165408.-1183029511.imp@bsdimp.com> In message: <4813.1245444080 at critter.freebsd.dk> "Poul-Henning Kamp" writes: : In message <20090619.143448.2102305600.imp at bsdimp.com>, "M. Warner Losh" writes : : : >In message: <4A3BF553.20205 at rubidium.dyndns.org> : > Magnus Danielson writes: : >: Have any of you seen the reported problems? : > : >"These counts started at 0 roughly at midnight UTC 6 Jan 1980" : > : >What does "roughly" mean here in this context? : : That the we have leap seconds. But midnight UTC time on 6 Jan 1980 was exactly the same thing as second 0 in GPS time. Leap seconds, while an evil complication to UTC, don't enter the synchronization point issue at all. It wasn't even Jan 1 when the leap second might have happened... Hence my confusion... Warner From brooke at pacific.net Fri Jun 19 22:55:02 2009 From: brooke at pacific.net (Brooke Clarke) Date: Fri, 19 Jun 2009 15:55:02 -0700 Subject: [time-nuts] Thunderbolt - any negatives ? In-Reply-To: References: Message-ID: <4A3C1746.80005@pacific.net> Hi Mike: I think it's National semi that has an app note talking about how the topology relates to noise output. Some are bad others are much better. Have Fun, Brooke Clarke http://www.prc68.com Mike Monett wrote: > > And be mindful that some frequency-standard devices contain > > integrated DC-DC switching converters - like my HP 58540A GPS-DO. > > > The noise from the HP DC converters was spraying RFI every 100 kHz > > or so on the HF bands. After trying various RFI abatement > > measures, including additional bypass C and toroid-wound #31 > > ferrite material, my solution was scrap the entire PS board and > > bring in clean power from a triple-output linear supply made by > > Power-One. There's no switch-mode component anywhere in the path > > of my GPS-DO. > > I'm having the opposite problem. The linear supply in my HP 53310A > Modulation Domain Analyzer spews out a huge magnetic field that > completely disupts any nearby equipment. For example, it causes a > fuzzy trace and triggering problems on TEK 2467B scopes, which makes > the scope unusable for low-level work. No amount of shielding has > helped. > > I'm seriously considering making the 53310A DC power section into a > switcher. I have developed some techniques that greatly reduce > crosstalk by mounting circuits on their own grounded platform. These > have a minimum number of connections to the main system ground, and > are chosen to minimize switching currents from flowing on the main > system ground. I put a brief description of the PST Prototype > Platform on my web site at > > http://pstca.com/spice/pstpp/pstpp.htm > > Another technique that can help is adding an active filter to the > output of the power supply. These can be very effective, but there > are a number of approaches that are well-publicized that don't work > very well. There is more analysis here: > > http://pstca.com/spice/ripple/ripple.htm > > Finally, Linear Technology supplies Low Noise Switching Regulators > that can give ripple values of less than 100uV, which is comparable > to or less than many linear regulators. If interested, see the links > in the above url. > > Noise can be a tricky problem, but the above information might give > some ideas to help tame it. > > Mike > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From peterawson at earthlink.net Fri Jun 19 23:28:39 2009 From: peterawson at earthlink.net (Pete) Date: Fri, 19 Jun 2009 17:28:39 -0600 Subject: [time-nuts] Thunderbolt - any negatives ? References: Message-ID: <3FFBE76BF7E440498CE63711F7D39866@BASE1> Mike, That PS is a most curious problem. For reduced leakage fields from 60Hz transformers, it was common to have a wide copper strap wrapped around the transformer in the same orientation as the windings. This strap was the full width of the winding bobbin, but formed a shorted turn on the outside of the transformer to reduce, or eliminate leakage flux. Does your tranformer have this shorted turn on it & is it still shorted? Any chance your line setting is 100V? This would certainly run the transformer towards saturation. Can you power that unit from a Variac & set the voltage down enough to see the external fields slack off? H-P had a rather conservative limit on external fields at power line frequeny & this was always verified during environmental testing, so I'm quite surprised you're seeing this issue. I think something is broken. Pete Rawson From ch at murgatroid.com Sat Jun 20 00:12:16 2009 From: ch at murgatroid.com (christopher hoover) Date: Fri, 19 Jun 2009 17:12:16 -0700 Subject: [time-nuts] Z3817A manual or details? Message-ID: <4A3C2960.7030100@murgatroid.com> Anyone else playing with one of these Z3817A boxes that are/were available on that marketplace which shall not be named? The Z3817A appears to be essential a discipling box for an E1938. I'm still not sure yet what the disciplining input is. I'd love a manual, but I haven't found one yet. So I've been doing some reverse engineering. On the TIB (P1) DB-25 connector, I'm fairly confident about these: V+ pins 1 and 21 V- pins 8 and 25 10MHz #1 pins 2/15 xfmr coupled, ~4.6V into 1M 10MHz #2 pins 23/16 xfmr coupled, ~4.6V into 1M 1PPS pin 14 Supply voltage is dictated by Lucent DC-DC converter. Input is 18-36V, 1.9A. Still chasing down the other pins. Currently I am working on a possible disciplining input: input of some kind to U6/3 via 100 ohms pin 18, prob. diff with 4 input of some kind to U6/2 via 100 ohms pin 4, prob. diff with 18 The MMI (J1) DB-9 connector is RS-232, 9600baud, 8n1 and runs a a familiar SCPI interface as you can see: scpi> *IDN? HEWLETT-PACKARD,Z3817A,3832A03064,3752-A scpi> :SYSTEM:STATUS? SYNCHRONIZATION ........................................... [ Outputs Invalid ] SmartClock Mode ___________________________ Reference Outputs _______________ Locked TFOM 9 FFOM 3 Recovery 1PPS TI -- Holdover HOLD THR 1.000 us >> Power-up: TIMEREF1 invalid Holdover Uncertainty ____________ Predict -- ACQUISITION ................................... [ TIMEREF1 (GPS) 1PPS Invalid ] Tracking: 0 ____ Not Tracking: 0 ________ Time ____________________________ TIME --:--:-- [?] -- --- ---- GPS 1PPS Invalid: not tracking ANT DLY -- Position ________________________ MODE Hold LAT -- LON -- ELEV MASK -- HGT -- HEALTH MONITOR ......................................................... [ OK ] Self Test: OK | Int Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK scpi > -ch From gcarlistaa at garychatters.com Sat Jun 20 03:35:49 2009 From: gcarlistaa at garychatters.com (Gary Chatters) Date: Fri, 19 Jun 2009 23:35:49 -0400 Subject: [time-nuts] OT favorite signal generator? In-Reply-To: <4A3B876B.1070603@rogers.com> References: <4A3B876B.1070603@rogers.com> Message-ID: <4A3C5915.5010506@garychatters.com> Patrick wrote: > Thanks John > > With regard to frequency and price, low frequency is fine for me and I > am hoping to buy something for < $250-Patrick > The HP 3336 (A,B,C) is similar to the 3325 but somewhat lesser capabilities and can be a bit cheaper. There is one on eBay "in working condition" for $150. Frequency range is 10 Hz to 21 MHz. Frequency is settable to uHz or mHz steps and it has frequency sweep capability. The output attenuator has 0.01dB steps and the output goes down to about -71 dBm. It is sine wave output only. If you want square or triangle, this won't do. If you need to go below about 10 Hz you will need a function generator. My impression from your description is that you do not need the capabilities of a synthesized signal generator. Perhaps an old analog test oscillator such as the HP 654A would be adequate. This is just an analog oscillator combined with a step attenuator that goes down to about -90dBm in 1 dB steps. There is one on eBay for $85 OBO, "tested". Or, for function generator capabilities (square, triangle, lower frequencies) an HP 3310A with an external attenuator. RF attenuators can be somewhat expensive, but audio ones are usually much less. I'll let others comment on whether anything that old might have too many problems. One advantage of the old analog stuff is that they are acoustically quiet (no fan). 73, Gary From xde-l2g3 at myamail.com Sat Jun 20 02:57:32 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Fri, 19 Jun 2009 23:57:32 -0300 Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: > Hi Mike: > I think it's National semi that has an app note talking about how > the topology relates to noise output. Some are bad others are much > better. > Have Fun, > Brooke Clarke > http://www.prc68.com Hi Brooke, Do you recall the number or title of the National app note? One of the techiques used in the Linear Technology Low Noise switchers is to limit the slew rate of the switching waveform. As mentioned in my web page, two models are: LT1533 - Ultralow Noise 1A Switching Regulator. This uses a conventional push-pull transformer with diode rectifiers on the secondary: and the LT1534 ultralow noise switching regulator. This one is for buck, boost, inverting, SEPIC, etc. The following app notes are also useful: AN70 A Monolithic Switching Regulator with 100uV Output Noise snan70 (corrects pin number errors in AN70) AN75 Circuitry for Signal Conditioning and Power Conversion AN118 - High Voltage, Low Noise, DC/DC Converters LT1533 Ultralow Noise Switching Regulator for High Voltage or High Current Applications I hope the links don't get mangled too badly! Mike From xde-l2g3 at myamail.com Sat Jun 20 03:28:19 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Sat, 20 Jun 2009 00:28:19 -0300 Subject: [time-nuts] Thunderbolt - any negatives ? Message-ID: > Mike, > That PS is a most curious problem. For reduced leakage fields from > 60Hz transformers, it was common to have a wide copper strap > wrapped around the transformer in the same orientation as the > windings. > This strap was the full width of the winding bobbin, but formed a > shorted turn on the outside of the transformer to reduce, or > eliminate leakage flux. > Does your tranformer have this shorted turn on it & is it still > shorted? > Any chance your line setting is 100V? This would certainly run the > transformer towards saturation. Can you power that unit from a > Variac & set the voltage down enough to see the external fields > slack off? > H-P had a rather conservative limit on external fields at power > line frequeny & this was always verified during environmental > testing, so I'm quite surprised you're seeing this issue. I think > something is broken. > Pete Rawson Hi Pete, I remember the copper strap from my younger days repairing tv sets for my neighbors. That was a long time ago:) The power transformer on the 53310A is huge - way bigger than it needs to be for the load. But I don't recall seeing the copper strap. As I recall, all four sides of the transformer were visible. I thought that was quite odd as I was expecting to see the copper strap. Part of the problem is the TEK 2467B is extremely sensitive to magnetic fields. The crt has a channel multiplier to allow viewing single-shot events at 1ns/div like the TEK 7104. So the deflection sensitivity is much higher than normal. The problem is definitely due to stray magnetic fields. The only way to have the two instruments turned on at the same time is to put one on a different bench. That is a bit awkward when you need to run back and forth to adjust the controls. The line voltage is 125V, so that's not the problem. Both instruments are pristine inside and seem to be working fine. The 2467B doesn't seem to be affected by any other instrument except the 53310A. Another small point. I mounted a fluorescent light under the top shelf where the TEK 2467B's sit. It turns out the small ballast inductor for the fluorescent light also delivers enough stray field to demolish the 2467B. I solved the problem temporarily by unscrewing the ballast and letting it hang down about 6 inches, supported by the leads. It's been like that for a long time. I was just looking at it now, and remembered that I promised myself I would mount it properly as soon as I had some time. So I think the 53310A is OK - maybe just a bit stronger field than usual. And the TEK is indispensable, so I just have to find ways to keep the stray fields away from the scope. BTW, both scopes show the same problem, so it's likely intrinsic to the design. Mike From kilodelta4foxmike at gmail.com Sat Jun 20 04:49:40 2009 From: kilodelta4foxmike at gmail.com (Brian Kirby) Date: Fri, 19 Jun 2009 23:49:40 -0500 Subject: [time-nuts] Thunderbolts for sale In-Reply-To: <4A3B19E2.8090903@xtra.co.nz> References: <4ECC7583323F41D38EFD9C7AD619FE53@athlon> <20090618.212803.-146244266.imp@bsdimp.com> <4A3B19E2.8090903@xtra.co.nz> Message-ID: <4A3C6A64.2090903@gmail.com> I will have two Trimble Thunderbolts GPSDO, that I will be selling. Both were bought thru the Time-Nuts purchases. There is nothing wrong with these units, they are operational, and surplus to my needs. One unit comes with the Ault power supply and power connector. The second unit comes without a power supply and I will be furnishing a pig-tailed power lead connector. I do not have pay-pal (sorry, I gave up on *bay...) and I can send COD. I can only make this offer for the lower 48 of the United States. If you are interested, please contact me off this list. Brian Kirby - KD4FM From magnus at rubidium.dyndns.org Sat Jun 20 11:33:03 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 20 Jun 2009 13:33:03 +0200 Subject: [time-nuts] Z3805 initial behavior after power up revised In-Reply-To: References: Message-ID: <4A3CC8EF.9020700@rubidium.dyndns.org> Francesco Ledda wrote: > Correction... > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Francesco Ledda > Sent: Friday, June 19, 2009 9:38 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Z3805 initial behavior after power up revised > > > Variation due to environment are deterministic and are nor part of aging. > Ageing needs to measured in conditions that remove ambient induced > perturbations. Not entierly true, as aging behaviour may be re-started or modified as environmental conditions change. > I used to put crystal oscillators in high quality > environmental chambers that kept temp, humidity and pressure constant and > measure the ageing. There are tricks that can be done to increase the aging > rate, so that we did not have to wait 20 years ;) > Strange, as the aging rate decreases over time, most of its aging and shift in frequency occur early. This occurs both in the "green" aging period, when it is new, but also after it has been turned off and cooled down / low temperature storage. So what tricks did you use? > We know that ageing happens, but the direction of ageing cannot be > determined. > A coin toss can yield face or tail. If the coin is perfect, the > distribution will be uniform. If a face is 1 and a tail is -1, we can add > successive tosses and track the total number. Even is the distribution of > tosses is uniform, the sum will walk away from 0 (random walk),cameback to 0 > and then move away from 0 again. This is a good way to model and explain > ageing. Nature is perfect, but things do not follow our math perfectly. A > better simulation would include a "leaky integral". > > The statistical analysis of ageing is tricky, since ageing doeas have NOT a > statistical mean, and therefore standard deviation cannot be used. > Standard deviation of frequency isn't used, but rather it is modeled thru the frequency drift component, and this is also described for different time-spans. Over time it integrates to the drifted frequency over that time. In all models it is treated separately from the noise components. The curvature of aging has also been established (see for instance Vig on the UFFC site), and with external reference (such as in a GPSDO), the parameters for that curve can be established and adjusted over time for better prediction of where the aging. Or is it that we have different concepts or environments in mind when we discuss aging? For me, aging is the shift in frequency over time as the oscillator is maintained at the same temperature. > This discussion brings lots of good memories back. The good old days when > SONET synchronization was a new thing, and we were creating new technology. > There are a few others here that was involved with that, and it would be fun to have a few discussion on that. Cheers, Magnus From richiem at hughes.net Sat Jun 20 19:31:03 2009 From: richiem at hughes.net (Dick Moore) Date: Sat, 20 Jun 2009 12:31:03 -0700 Subject: [time-nuts] Volt-nuts cooperation? Message-ID: <7451D39B-6EFD-4CF0-B19A-DD0342BB2ACE@hughes.net> A couple of times a year, I could really use an HP 3458A. No way can I justify spending upwards of $4-5k for such limited use. So, maybe some of us could form a buyer/user group to share the cost of one of these instruments, which could put it in the range of affordability for each. For example, ten of us could have the instrument for two weeks each twice a year, and the cost for each comes down to that for a 34401A. These instruments ship well (at least within the continental US, via FedEx or UPS), are very stable, and self-calibrate, needing a full cal (which uses a 10kohm resistor and a 10VDC source) once every couple of years to keep within tolerable specs. I've rented one once and I found that it really needed to self-cal once every couple of days to stay repeatable, especially on ohms and AC. My confidence in my Fluke 5440B Direct Valtage Calibrator, two Fluke 732A 10V standards, and two Datron 1082 7-1/2-digit DMMs would go way up, not to mention keeping a few other things checked and accounted for, like resistance standards. I'm willing to ante-up up to $1k to get us started, if there is any interest here among the US time-nuts. Best to reply to me at: richiem at hughes.net. We can work our details if the interest is sufficient. Best, Dick Moore From lstoskopf at cox.net Sat Jun 20 20:09:34 2009 From: lstoskopf at cox.net (lstoskopf at cox.net) Date: Sat, 20 Jun 2009 16:09:34 -0400 Subject: [time-nuts] LF power supply noise In-Reply-To: Message-ID: <20090620160934.LZ1FR.406000.imail@eastrmwml35> Again, you might try electronic goldmine's mu metal shielding. Used to be used as a shield around CRTs, etc. Their version is sticky on one side so might make a good trial wrap. N0UU From magnus at rubidium.dyndns.org Sat Jun 20 20:18:54 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 20 Jun 2009 22:18:54 +0200 Subject: [time-nuts] LF power supply noise In-Reply-To: <20090620160934.LZ1FR.406000.imail@eastrmwml35> References: <20090620160934.LZ1FR.406000.imail@eastrmwml35> Message-ID: <4A3D442E.5070102@rubidium.dyndns.org> lstoskopf at cox.net skrev: > Again, you might try electronic goldmine's mu metal shielding. Used to be used as a shield around CRTs, etc. Their version is sticky on one side so might make a good trial wrap. I has issues with the big permanent magnet of one of my speakers made one of my screens going all strange in colours. I had some backsides from a pair of racks which I put inbetween, and the steel was doing a good job as finding a better path for the magnetic fields than through my screen. Maybe you should put a few slabs of steel around that HP543310A to at least guide most of the magnetic fields back into the core. Cheers, Magnus From wb6bnq at cox.net Sat Jun 20 20:50:08 2009 From: wb6bnq at cox.net (WB6BNQ) Date: Sat, 20 Jun 2009 13:50:08 -0700 Subject: [time-nuts] Volt-nuts cooperation? References: <7451D39B-6EFD-4CF0-B19A-DD0342BB2ACE@hughes.net> Message-ID: <4A3D4B80.5616242B@cox.net> Hi Dick, I am a little confused as to your needs. On the one hand you feel the hp3458A is a fine instrument only needing ?CAL? every 2 years, yet you then say it needed to be ?CAL?d? every 2 days to stay repeatable. That does not sound very encouraging and is indicative of other problems. I would like to know why you feel this particular instrument is so crucial ? Particularly as you have within your own means just about everything to verify your own equipment beyond anything reasonably needed. The only item missing from your list is a damn good null meter; the Fluke 845. You have the best there is in a voltage standard with the 732A, assuming they are working correctly and verified (i.e., calibrated) by a highly reputable source like Fluke. Even without the null meter you could easily jump start your own verification process to improve your confidence. The only other ?NICE? thing to have would be Fluke 720A Kelvin-Varley divider. For $1000 you could easily obtain the 845 and 720A. With the 720A you could prove, without doubt, each and every digit in your 7 ? digit meters, not to mention the 5440B. The race for digits is a fun ?hobby? but a truly wasteful effort because the real world does not operate in a finely tuned calibration lab with every nuance of the environment controlled beyond reason. Even if you had such a lab in the basement (some do), playing around at even just 6 digits requires knowing how to account for a number of not so easily proved variables in the measurement process. Of course, if this is a commercial concern like trying to satisfy a government contract, then all bets are off. Such a game guarantees the race. Bill....WB6BNQ wb6bnq at cox.net Dick Moore wrote: > A couple of times a year, I could really use an HP 3458A. No way can I > justify spending upwards of $4-5k for such limited use. So, maybe some > of us could form a buyer/user group to share the cost of one of these > instruments, which could put it in the range of affordability for > each. For example, ten of us could have the instrument for two weeks > each twice a year, and the cost for each comes down to that for a > 34401A. > > These instruments ship well (at least within the continental US, via > FedEx or UPS), are very stable, and self-calibrate, needing a full cal > (which uses a 10kohm resistor and a 10VDC source) once every couple of > years to keep within tolerable specs. I've rented one once and I found > that it really needed to self-cal once every couple of days to stay > repeatable, especially on ohms and AC. > > My confidence in my Fluke 5440B Direct Valtage Calibrator, two Fluke > 732A 10V standards, and two Datron 1082 7-1/2-digit DMMs would go way > up, not to mention keeping a few other things checked and accounted > for, like resistance standards. > > I'm willing to ante-up up to $1k to get us started, if there is any > interest here among the US time-nuts. > > Best to reply to me at: > richiem at hughes.net. > > We can work our details if the interest is sufficient. > > Best, > Dick Moore > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From rexa at sonic.net Sat Jun 20 21:23:53 2009 From: rexa at sonic.net (Rex) Date: Sat, 20 Jun 2009 14:23:53 -0700 Subject: [time-nuts] My HP5370A performance In-Reply-To: <4A3BDB94.1040301@sonic.net> References: <4A3BDB94.1040301@sonic.net> Message-ID: <4A3D5369.2060809@sonic.net> Rex wrote: > Bruce and John, > > Thanks for pointing me back to these operator checks. I ran through > the procedures this morning and nothing seems out of spec. I guess I > just had unrealistic expectations about how stable the displays should > be while looking at that counter's own clock. > > Here's my results from the Operators Checks on 3-11, 3-12: > > [Snip] > I just wanted to say thanks for the nudge in the right direction on evaluating my counter and for the comments about my numbers. Pete, especially, gave a nice, concise summary about the counter. -Rex From holrum at hotmail.com Sat Jun 20 22:04:35 2009 From: holrum at hotmail.com (Mark Sims) Date: Sat, 20 Jun 2009 22:04:35 +0000 Subject: [time-nuts] Volt-nuts cooperation? In-Reply-To: References: Message-ID: The 3458A has two types of calibrations. The first is done every year or two using the external references. The other is an internal self calibration which you should run every day or two. This is pretty much standard for every high res meter on the market today (except most want you to send it to the external cal lab every six months) The 3458A is probably the best meter on the market. It seems like multimeters pretty much stopped evolving with this unit. Basically 8.5 digits seems to be the practical limit of resolution that you can extract from silicon devices. 8.5 digit meters have been available for around over 20 years now. Nobody seems to have come out with anything better in the last 20+ years. As far as spending $4-5K for a 3458A, if you are patient and a little lucky you can score one for half that. I bought one for under $1500 (but sold it after I was made an offer I could not refuse). My latest one cost $2500. There is one on Ebay right now that opens at $1600. I suspect it will sell for under $2800. ---------------------------------------- I am a little confused as to your needs. On the one hand you feel the hp3458A is a fine instrument only needing ?CAL? every 2 years, yet you then say it needed to be ?CAL?d? every 2 days to stay repeatable. That does not sound very encouraging and is indicative of other problems. _________________________________________________________________ Hotmail? has ever-growing storage! Don?t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 From frledda at verizon.net Sat Jun 20 22:30:19 2009 From: frledda at verizon.net (Francesco Ledda) Date: Sat, 20 Jun 2009 17:30:19 -0500 Subject: [time-nuts] Volt-nuts cooperation? In-Reply-To: Message-ID: Lucky me, I bought an HP3455A new still in the box for $300! -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Mark Sims Sent: Saturday, June 20, 2009 5:05 PM To: time-nuts at febo.com Subject: [time-nuts] Volt-nuts cooperation? The 3458A has two types of calibrations. The first is done every year or two using the external references. The other is an internal self calibration which you should run every day or two. This is pretty much standard for every high res meter on the market today (except most want you to send it to the external cal lab every six months) The 3458A is probably the best meter on the market. It seems like multimeters pretty much stopped evolving with this unit. Basically 8.5 digits seems to be the practical limit of resolution that you can extract from silicon devices. 8.5 digit meters have been available for around over 20 years now. Nobody seems to have come out with anything better in the last 20+ years. As far as spending $4-5K for a 3458A, if you are patient and a little lucky you can score one for half that. I bought one for under $1500 (but sold it after I was made an offer I could not refuse). My latest one cost $2500. There is one on Ebay right now that opens at $1600. I suspect it will sell for under $2800. ---------------------------------------- I am a little confused as to your needs. On the one hand you feel the hp3458A is a fine instrument only needing ?CAL? every 2 years, yet you then say it needed to be ?CAL?d? every 2 days to stay repeatable. That does not sound very encouraging and is indicative of other problems. _________________________________________________________________ Hotmail? has ever-growing storage! Don?t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutoria l_Storage_062009 _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From bruce.griffiths at xtra.co.nz Sat Jun 20 23:06:32 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sun, 21 Jun 2009 11:06:32 +1200 Subject: [time-nuts] LF power supply noise In-Reply-To: <4A3D442E.5070102@rubidium.dyndns.org> References: <20090620160934.LZ1FR.406000.imail@eastrmwml35> <4A3D442E.5070102@rubidium.dyndns.org> Message-ID: <4A3D6B78.50406@xtra.co.nz> Magnus Danielson wrote: > lstoskopf at cox.net skrev: >> Again, you might try electronic goldmine's mu metal shielding. Used >> to be used as a shield around CRTs, etc. Their version is sticky on >> one side so might make a good trial wrap. > > I has issues with the big permanent magnet of one of my speakers made > one of my screens going all strange in colours. I had some backsides > from a pair of racks which I put inbetween, and the steel was doing a > good job as finding a better path for the magnetic fields than through > my screen. > > Maybe you should put a few slabs of steel around that HP543310A to at > least guide most of the magnetic fields back into the core. > > Cheers, > Magnus > If the magnetic field is too high the mu metal will saturate so using a high saturation ferromagnetic material to reduce the field seen by the mu metal itself may be necessary. One has to be careful in the selection of the steel to be used as some alloys can be only weakly ferromagnetic. Bruce From holrum at hotmail.com Sun Jun 21 00:55:20 2009 From: holrum at hotmail.com (Mark Sims) Date: Sun, 21 Jun 2009 00:55:20 +0000 Subject: [time-nuts] Volt-nuts cooperation? In-Reply-To: References: Message-ID: Not nearly as good a deal as my $50 including manuals and shipping HP 3457A... you gotta love sellers that don't check the fuse... Also one should be very wary of new-in-box vintage equipment. It tends to have a much greater failure rate than used equipment! The major culprit is bad electrolytic capacitors. Electrolytic caps that had never really been powered up and that sat unused for ages tend to fail much more often than caps that had been powered up for a reasonable amount of time early in their life (even if they then sat unused for extended periods). ----------------------------- Lucky me, I bought an HP3455A new still in the box for $300! _________________________________________________________________ Hotmail? has ever-growing storage! Don?t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 From ed_palmer at sasktel.net Sun Jun 21 03:35:08 2009 From: ed_palmer at sasktel.net (Ed Palmer) Date: Sat, 20 Jun 2009 21:35:08 -0600 Subject: [time-nuts] Volt-nuts cooperation? In-Reply-To: References: Message-ID: <4A3DAA6C.7040303@sasktel.net> Does this happen even if the electrolytics are reformed before use? Ed Mark Sims wrote: > Not nearly as good a deal as my $50 including manuals and shipping HP 3457A... you gotta love sellers that don't check the fuse... > > Also one should be very wary of new-in-box vintage equipment. It tends to have a much greater failure rate than used equipment! The major culprit is bad electrolytic capacitors. Electrolytic caps that had never really been powered up and that sat unused for ages tend to fail much more often than caps that had been powered up for a reasonable amount of time early in their life (even if they then sat unused for extended periods). > > > ----------------------------- > Lucky me, I bought an HP3455A new still in the box for $300! > _________________________________________________________________ > Hotmail? has ever-growing storage! Don?t worry about storage limits. > http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From frledda at verizon.net Sun Jun 21 04:00:56 2009 From: frledda at verizon.net (Francesco Ledda) Date: Sat, 20 Jun 2009 23:00:56 -0500 Subject: [time-nuts] Volt-nuts cooperation? In-Reply-To: Message-ID: I agree that electrolit like to fail, after years of sitting on a shelf. I have had the 3455 for 6/7 years, and has not given me any problems. Year ago, a brand new RF section for an 8568 found me; this has been good, as well. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Mark Sims Sent: Saturday, June 20, 2009 7:55 PM To: time-nuts at febo.com Subject: [time-nuts] Volt-nuts cooperation? Not nearly as good a deal as my $50 including manuals and shipping HP 3457A... you gotta love sellers that don't check the fuse... Also one should be very wary of new-in-box vintage equipment. It tends to have a much greater failure rate than used equipment! The major culprit is bad electrolytic capacitors. Electrolytic caps that had never really been powered up and that sat unused for ages tend to fail much more often than caps that had been powered up for a reasonable amount of time early in their life (even if they then sat unused for extended periods). ----------------------------- Lucky me, I bought an HP3455A new still in the box for $300! _________________________________________________________________ Hotmail? has ever-growing storage! Don?t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutoria l_Storage_062009 _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From GandalfG8 at aol.com Sun Jun 21 10:03:23 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sun, 21 Jun 2009 06:03:23 EDT Subject: [time-nuts] OT favorite signal generator? Message-ID: In a message dated 19/06/2009 15:42:15 GMT Daylight Time, optomatic at rogers.com writes: I was thinking that if I injected a signal with a known waveform I could follow it around the amplification circuits and such. My only real need is to create something that does not appear to already be there. For instance I don't see many triangle waves, if I produced one I could following it around with my oscilloscope. So in terms of frequency just a few hertz would do, heck even 1 would probably be fine. My only concern is that some of the circuits are high impedance and have low voltages. It might be a good idea if I could get down somewhere into the uV range. ---------------------- Then forget distortion specs and HP kit, nice as it is, etc etc, all you really need is the cheapest function generator you can find. Most, if not all, will go down to a few Hz and all should give you a triangular waveform. Frequency calibration is often poor, and output level accuracy too, but that shouldn't matter for what you need. Most do have relatively high outputs compared to decent signal generators but a fixed attenuator to bring it into the range you need, easily knocked up with a few resistors, should fix that and you can then adjust using the built in level control. Building something to match your stated requirements wouldn't be difficult either and shouldn't require anything more than a handful of components costing just a few dollars. regards Nigel GM8PZR From xde-l2g3 at myamail.com Sun Jun 21 13:37:31 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Sun, 21 Jun 2009 10:37:31 -0300 Subject: [time-nuts] LF power supply noise References: <4A3D442E.5070102@rubidium.dyndns.org> Message-ID: >> Again, you might try electronic goldmine's mu metal shielding. >> Used to be used as a shield around CRTs, etc. Their version is >> sticky on one side so might make a good trial wrap. > I has issues with the big permanent magnet of one of my speakers > made one of my screens going all strange in colours. I had some > backsides from a pair of racks which I put inbetween, and the > steel was doing a good job as finding a better path for the > magnetic fields than through my screen. > Maybe you should put a few slabs of steel around that HP543310A to > at least guide most of the magnetic fields back into the core. >Cheers, >Magnus Hi Magnus, I was having the same problem with funny colors until I switched to LCD monitors. The problem went away:) I did try putting a large steel plate between the 543310A and the 2467B. The plate was 12"X12"X1/4" (30.48cm X 30.48cm X 0.635cm), and I checked it with a magnet to verify it was magnetic, but it had little effect. One of the reasons I was attracted to the 543310A was it could display 14 digits of frequency in one second. Sine then, I have figured a way to resolve 16 digits in one second, so that part of the spec is no longer interesting. The 543310A can do a single-shot time measurement with a resolution of 200ps, and gets down to 1ps with averaging. The HP5370B does 20ps single-shot, and will resolve 100fs with averaging. But I have figured a way to measure 2ps single-shot, and a bit better with averaging. So that part of the spec is not so interesting any more. The 543310A will display the phase and frequency changes in a PLL step response. But you can get the frequency response just by looking at the VCO DC error voltage. And if you look at the voltage across the bottom capacitor in a type 3 loop, you get the phase response. Here's a picture: -------------------------> to VCO | --- C1 --- | |----------O < - Phase Error | | --- C2 \ --- / R1 | \ | | --- --- - - So about the only thing left of interest is histograms of the jitter. Unfortunately, the 543310A cannot store enough samples to really make an interesting graph. What I would like to be able to do is similar to an invention I made for the disk industry long ago, called Phase Margin Analysis. There is a brief description on my web page at http://pstca.com/patents.htm#phasemargin There is a more detailed description in the paper, "Effect of Bitshift Distribution on Error Rate in Magnetic Recording", by Eric Katz and Tom Campbell, at http://pstca.com/pdfs/katz.pdf But it doesn't look like the 543310A will be able to do that. Now that I can beat most of the performance specs of the 543310A, it doesn't seem worthwhile to spend much time trying to solve the problem of stray magnetic fields. So it looks like that problem is not worth pursuing any more. But this might be a good time to give you a progress report on what I have been up to these past months. Some time ago, I mentioned I had a way to measure time difference with very high resolution. This is similar to what you are trying to do with DMTD, but I'm confident I can get down to 1e-16 in one second, and also provide continuous measurements for Allen Deviation calculations. The technique uses Binary Sampling, and there is a brief description on my web site at http://pstca.com/ Since then, I have combined the other developments and came up with a completely new way of locking a OXCO to the 1pps GPS signals. This uses Binary Sampling to eliminate the noise due to granularity and sawtooth error, and should give at least one order of magnitude or more improvement in performance over anything else that is available. The improved performance means you have to start tracking the delays in the GPS antenna amplifier and the coax to the receiver, and incorporate them as offsets in the timing. I have figured a way to measure the changes in electrical length of the coax due to temperature to better than 1 ps resolution, and can either measure the temperature of the preamplifier or control it by sending power up the coax. All this is using one single coax. Another project in the works is a system to do a three-corner hat with 1e-16 resolution, with extensions for more channels. I think I can fit 6 channels in a reasonable size box. Another project is to measure amplitude and phase noise. The quadrature method looks most useful, but getting a PLL to give stable quadrature lock is problematic. Again, Binary Sampling comes to the rescue, and I am confident I can make a phase noise measurement equal to or better than anything on the market. On a side issue, we all suffer from colds and flu infections. These are usually caused by a virus, and the medical field has nothing that can treat viral infections and kill the virus. Just like we need trace amounts selenium and chromium, I believe the immune system also needs trace amounts of silver to manufacture the enzymes and proteins necessary to kill viruses. The problem is unlike sodium, potassium, and calcium, silver compounds are either poisonous, highly explosive, or completely insoluble. And the silver must be in ionic form to be usable by the body. I have been working on ways to generate high concentrations of silver ions in solution for many years, and have just reached the final breakthrough in solving the myriad problems. There is a brief description on my web site at http://www.pstca.com/silversol/index.htm The new breakthrough is not described yet, but I am making a new type of generator that solves all these problems and will start selling it in eBay soon. Finally, I have the misfortune to suffer from serious case of mycotoxosis for many years. This is a devastating problem, and is completely incapacitating. There is a brief description at http://www.ibd.ab.ca/files/Mould-chap2.pdf but it does not describe how serious the problem can be. Just for example, the toxins on Amanita virosa produces one of the most potent poisons known to pharmacologists. I read somewhere that a couple of micrograms of some mold toxins will kill someone in less than 24 hours, and the toxins are metabolized so they disappear. This is apparently used by some countries for assassination, since an autopsy will conclude the death was by natural causes. Mycotoxosis is incurable, and the only solution is to completely eliminate any kind of mold spores in the environment. This turns out to be very difficult to do. The spores grow on most fabrics, especially cotton, and they cannot be killed with bleach or any other common household chemical. They require temperatures over 240F to start having any effect, and it is difficult or impossible to heat fabrics to these temperatures without melting them or starting a fire. Ozone can kill them by removing the outer protective shell, but it is very difficult to generate high enough ozone concentrations. Also, ozone generation requires very low humidity, which is difficult to obtain in the summer when temperatures and humidity are high. But I have found a very effective solution and am in the process of making a system to sterilize fabrics. This will be of great interest to hospitals, clinics, retirement homes, and to anyone else who may be affected by mold toxins. One way of reducing the spore concentration in the air is by filtering. Unfortunately, the spores grow on most filter mediums so the filter becomes a source of spores. I have developed a new type of filter that has no organic or synthetic material, so there is no place for the spores to grow. These innovations will be of great benefit to others who suffer from allergies, so I am in the process of developing several new businesses to bring them to market. As you can see, I have a lot of very interesting things to do to keep me busy. I'll be sure to keep you updated on developments in the time and frequency areas, and if anyone is interested in the elimination of colds, flu, Shingles, dental cavities, peptic ulcers, and the removal of moles and warts, you can contact me separately via the address on my Silversol web site. Thanks, Mike From magnus at rubidium.dyndns.org Sun Jun 21 16:01:33 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 21 Jun 2009 18:01:33 +0200 Subject: [time-nuts] LF power supply noise In-Reply-To: References: <4A3D442E.5070102@rubidium.dyndns.org> Message-ID: <4A3E595D.6040109@rubidium.dyndns.org> Mike, > Hi Magnus, > > I was having the same problem with funny colors until I switched to > LCD monitors. The problem went away:) > > I did try putting a large steel plate between the 543310A and the > 2467B. The plate was 12"X12"X1/4" (30.48cm X 30.48cm X 0.635cm), and > I checked it with a magnet to verify it was magnetic, but it had > little effect. Maybe it was not a suitable variant of steel. I used a pair of backsides from a pair of 10 U Schroff racks, no particular steel at all, and it proved useful to reduce the effects. Just as Bruce pointed out, steel is not one thing, but magnetic permeability can change quite drastically, so I just had good luck where as you didn't have such a good luck. Also, aligning it properly for the field should increase the coupling effect between the steel and the transformer... which is the important part. > One of the reasons I was attracted to the 543310A was it could > display 14 digits of frequency in one second. Sine then, I have > figured a way to resolve 16 digits in one second, so that part of > the spec is no longer interesting. As was described by J. J. Snyder in "An Ultra-High Resolution Frequency Meter" in the FCS 1981 (as available from IEEE UFFC) I assume, basically using the fact that adding more measurements in a dense time raises the degrees of freedom and allows for quicker interpolation. Modern counters like HP 53131, HP 53132 as well as Pendulum CNT-90 or Fluke 6690 uses similar approaches. As being reported, such mechanisms does not fair well with ADEV calculations, and especially the overlapping variants of ADEV and den MDEV and TDEV which was inspired by that particular article, so using it twice forms unwanted filters. > The 543310A can do a single-shot time measurement with a resolution > of 200ps, and gets down to 1ps with averaging. The HP5370B does 20ps > single-shot, and will resolve 100fs with averaging. But I have > figured a way to measure 2ps single-shot, and a bit better with > averaging. So that part of the spec is not so interesting any more. I assume you really mean HP 53310A and not HP 543310A, even if your typing is consistent. The listed numbers is when weigthing in how various jitter sources combine upon averaging and should be considered a bit conservative. By all means describe what you mean by 2 ps single-shot resolution. > The 543310A will display the phase and frequency changes in a PLL > step response. But you can get the frequency response just by > looking at the VCO DC error voltage. And if you look at the voltage > across the bottom capacitor in a type 3 loop, you get the phase > response. Here's a picture: > > -------------------------> to VCO > | > --- C1 > --- > | > |----------O < - Phase Error > | | > --- C2 \ > --- / R1 > | \ > | | > --- --- > - - You should recall that when HP built their line of analyzers, they where thinking "what can we make this cool ZDT core do?" rather than attempting to build the best analyzer for all responsens. > So about the only thing left of interest is histograms of the > jitter. Unfortunately, the 543310A cannot store enough samples to > really make an interesting graph. What I would like to be able to do > is similar to an invention I made for the disk industry long ago, > called Phase Margin Analysis. There is a brief description on my web > page at > > http://pstca.com/patents.htm#phasemargin Somewhere in my map of apps there is a HP appnote for doing the same, to discs, intended for disc industry, back in the days. The HP 5372A and onwards (HP 5373A and HP 53310A) include hardware histograms, to increase the rate of histogram builing. Use that rather than the software more histograms. I don't know the details for the HP 53310A as I have never used one, but having a look at them it looks like it also has the fast histogram measurement engine, which is also described in detail by the patent... the HP 5371A did not have the hardware histogram, so it uses software instead. > There is a more detailed description in the paper, "Effect of > Bitshift Distribution on Error Rate in Magnetic Recording", by Eric > Katz and Tom Campbell, at > > http://pstca.com/pdfs/katz.pdf > > But it doesn't look like the 543310A will be able to do that. > > Now that I can beat most of the performance specs of the 543310A, it > doesn't seem worthwhile to spend much time trying to solve the > problem of stray magnetic fields. The 53310A was a nice convenient tool at its time, but it's performance isn't up to spec with modern times. It seems like HP didn't pursue it into much deeper levels after its VXI instruments, where as others went deeper. Cheers, Magnus From w9ac at arrl.net Sun Jun 21 16:18:51 2009 From: w9ac at arrl.net (Paul Christensen) Date: Sun, 21 Jun 2009 12:18:51 -0400 Subject: [time-nuts] GPSDO 10 MHz Distribution Amp Message-ID: <000819CC0D4449478A872A2FEA60D58A@DBTOA000> In the next couple weeks, I plan on distributing the output of my GPSDO to a pair of Icom transceivers. I've thought about using a DA like the TAPR TADD-1, but it seems that I can simply split the output of the +13 dBm GPSDO with a Z=50, 3dB equal power divider, that will yield an output of ~ +9.5 dBm to each transceiver. I can't foresee any port isolation issues that would make necessitate the use of the DA for this application and the 3 dB "hit" in level to each transceiver still seems reasonable for proper transceiver operation. Am I not considering something important? Also, I do not want to add any noise with such a distribution that would in any way destroy the excellent phase noise characteristics of my GPSDO. Thoughts? Paul, W9AC From holrum at hotmail.com Sun Jun 21 16:21:39 2009 From: holrum at hotmail.com (Mark Sims) Date: Sun, 21 Jun 2009 16:21:39 +0000 Subject: [time-nuts] Bad capacitors (was Volt-nuts cooperation?) In-Reply-To: References: Message-ID: The problems I saw were mostly hard failures in the caps (opens/shorts/etc). These were in both power caps and signal caps. One lot that I saw was a group of 12 Mettler scales. 6 were used daily and 6 were never used backup units. When the company shut down the operations that used the scales, they were sold. All the used units worked fine. The backup units all had capacitor problems. I also bought a lot of new-in-box Tektronix TM500 modules. Most wound up having flakey capacitors. BTW, EVERY (new or used) Tek PG505 pulse generator you will come across will have bad power supply filter caps... unless they were replaced. ---------------------------------------- Does this happen even if the electrolytics are reformed before use? _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From g4hup at btinternet.com Sun Jun 21 16:34:09 2009 From: g4hup at btinternet.com (dave powis) Date: Sun, 21 Jun 2009 16:34:09 +0000 (GMT) Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In-Reply-To: <000819CC0D4449478A872A2FEA60D58A@DBTOA000> References: <000819CC0D4449478A872A2FEA60D58A@DBTOA000> Message-ID: <55232.44839.qm@web86304.mail.ird.yahoo.com> Hi Paul, Sounds a reasonable approach to me where an equal 2 way split is needed, and you already have adequate signal level available. May not be up to 'time-nuts' precision etc, but it is a practical method that will give what you need. If you ever need to remove one Rig, just remember to terminate the unused split output in 50R! However, when you get yourself an analyser, sig gen or counter that takes the 10MHz reference, then you will need a DA! Comeback to me (http://g4hup.com) or TAPR then! 73, Dave http://g4hup.com ________________________________ From: Paul Christensen To: Discussion of precise time and frequency measurement Sent: Sunday, 21 June, 2009 5:18:51 PM Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In the next couple weeks, I plan on distributing the output of my GPSDO to a pair of Icom transceivers. I've thought about using a DA like the TAPR TADD-1, but it seems that I can simply split the output of the +13 dBm GPSDO with a Z=50, 3dB equal power divider, that will yield an output of ~ +9.5 dBm to each transceiver. I can't foresee any port isolation issues that would make necessitate the use of the DA for this application and the 3 dB "hit" in level to each transceiver still seems reasonable for proper transceiver operation. Am I not considering something important? Also, I do not want to add any noise with such a distribution that would in any way destroy the excellent phase noise characteristics of my GPSDO. Thoughts? Paul, W9AC _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From frledda at verizon.net Sun Jun 21 16:58:07 2009 From: frledda at verizon.net (Francesco Ledda) Date: Sun, 21 Jun 2009 11:58:07 -0500 Subject: [time-nuts] Bad capacitors (was Volt-nuts cooperation?) In-Reply-To: Message-ID: I believe you. You know that its is better to be lucky than smart ;) -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Mark Sims Sent: Sunday, June 21, 2009 11:22 AM To: time-nuts at febo.com Subject: [time-nuts] Bad capacitors (was Volt-nuts cooperation?) The problems I saw were mostly hard failures in the caps (opens/shorts/etc). These were in both power caps and signal caps. One lot that I saw was a group of 12 Mettler scales. 6 were used daily and 6 were never used backup units. When the company shut down the operations that used the scales, they were sold. All the used units worked fine. The backup units all had capacitor problems. I also bought a lot of new-in-box Tektronix TM500 modules. Most wound up having flakey capacitors. BTW, EVERY (new or used) Tek PG505 pulse generator you will come across will have bad power supply filter caps... unless they were replaced. ---------------------------------------- Does this happen even if the electrolytics are reformed before use? _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From xde-l2g3 at myamail.com Sun Jun 21 18:27:54 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Sun, 21 Jun 2009 15:27:54 -0300 Subject: [time-nuts] LF power supply noise References: Message-ID: > Mike, [...] >> One of the reasons I was attracted to the 543310A was it could >> display 14 digits of frequency in one second. Sine then, I have >> figured a way to resolve 16 digits in one second, so that part of >> the spec is no longer interesting. > As was described by J. J. Snyder in "An Ultra-High Resolution > Frequency Meter" in the FCS 1981 (as available from IEEE UFFC) I > assume, basically using the fact that adding more measurements in > a dense time raises the degrees of freedom and allows for quicker > interpolation. > Modern counters like HP 53131, HP 53132 as well as Pendulum CNT-90 > or Fluke 6690 uses similar approaches. I can't find any copies that are not payware, but it is unlikely there is any connection between the methods. Conventional averaging methods are limited by the exponential rise in number of samples that are required to improve the SNR. The measurement ends up taking too long, or the system drifts which renders the mesurement useless. This provides an effective barrier to the amount of improvement possible in SNR, and the available precision that is possible with conventional technology. Binary Sampling works a completely different way. It ignores the amplitude of the sample, and only records the direction of the error. According to the Central Limit Theorem, the mean of Gaussian noise is zero. This forces the Binary Sampler to converge on the true value of the signal, and ignore the error caused by the amplitude of the sample. This is a really big thing. The problem of using averaging to improve sigma has existed for over 109 years. And nobody has been able to solve it up till now. With a heterodyne sampling system, or conventional mixer technology, the sample delta is the offset frequency divided by the square of the reference frequency: Delta = Offset / Ref * Ref With a delta of 1Hz and reference of 1 MHz, the sample delta is 1 / (1e6)^2 = 1 / 1e12, or 1 picosecond. Since the Binary Sampler discards noise, the result is 1 picosecond resolution in 1 second. I show this on my web site. The schematic for the measurement is shown in Fig. 1 at http://pstca.com/sampler/design.htm A simple boxcar smoother is used to integrate the samples. The result with different smoothing values is shown at http://pstca.com/sampler/smooth.htm A system with 18.38 ps rms jitter would require averaging 338 waveforms to obtain 1ps rms jitter. With conventional sampling technology, this would require 169 seconds, and the system would probably drift during the measurement, rendering the measurement invalid. So it is not possible to obtain this amount of improvement in this system, and the measurement is impossible. The Binary Sampler gives 1ps resolution in 1 second. This is shown in Fig. 4 at http://pstca.com/sampler/binsamp.htm No other system can achieve this performance. And anyone with sufficient skill can duplicate this result at home. Extending this to higher frequency, it should be possible to obtain a 1Hz offset at 100MHz with 1 uHz resolution. This gives 1 / (1e8)^2 = 1e-16 resolution in 1 second. I do not think any existing equipment from HP, Fluke, or Pendulum or anyone else can come close to matching this level of performance. Also, existing technology must deal with noise and the averaging problem. This eliminates much of the performance boundaries from consideration. As a result, conventional technology cannot reach 1e-16 in one second. > As being reported, such mechanisms does not fair well with ADEV > calculations, and especially the overlapping variants of ADEV and > den MDEV and TDEV which was inspired by that particular article, > so using it twice forms unwanted filters. My approach delivers continuous samples. No missing or extra bits. >> The 543310A can do a single-shot time measurement with a >> resolution of 200ps, and gets down to 1ps with averaging. The >> HP5370B does 20ps single-shot, and will resolve 100fs with >> averaging. But I have figured a way to measure 2ps single-shot, >> and a bit better with averaging. So that part of the spec is not >> so interesting any more. > I assume you really mean HP 53310A and not HP 543310A, even if > your typing is consistent. The listed numbers is when weigthing in > how various jitter sources combine upon averaging and should be > considered a bit conservative. > By all means describe what you mean by 2 ps single-shot > resolution. That will cure me of trying to type complex numbers when copy and paste works so much better. But now I have to try and figure out what your "weigthing" really means:) The 2ps single shot is dead straight conventional time-to-time conversion. Nothing new there, except I think I have some new tricks on stabilizing the circuits against drift, and providing a much faster response to the zero-crossing at the end of the timing interval. All these reduce the noise in the sampling process. But the real trick is applying the Binary Sampling technique to the result. That allows a huge reduction in the noise from the sampling process, and converges rapidly on a much more precise solution. >> The 543310A will display the phase and frequency changes in a PLL >> step response. But you can get the frequency response just by >> looking at the VCO DC error voltage. And if you look at the >> voltage across the bottom capacitor in a type 3 loop, you get the >> phase response. Here's a picture: >> | >> --- C1 >> --- >> | >> |----------O < - Phase Error >> | | >> --- C2 \ >> --- / R1 >> | \ >> | | >> --- --- >> - - > You should recall that when HP built their line of analyzers, they > where thinking "what can we make this cool ZDT core do?" rather > than attempting to build the best analyzer for all responsens. I have a slightly different impression. I sold a lot of equipment to Boisie, Idaho, and I used to make a lot of trips there in my Piper Malibu, which was about the only realistic way of getting there from San Jose: http://www.jetphotos.net/viewphoto.php?id=5874208&nseq=0 There was a lot of political infighting at Boisie involved in development of new equipment. The winner pretty much had whatever say he wanted in the direction, and he ignored the input from other competent engineers. As a result, the equipment was limited by that individual's scope and abilities. The result is much of HP's equipment suffered. One example is the 20ps single-shot resolution of the HP 5370B has never been matched by any later equipment, as far as I know. A few engineers at Boisie complained bitterly about the loss. >> So about the only thing left of interest is histograms of the >> jitter. Unfortunately, the 543310A cannot store enough samples to >> really make an interesting graph. What I would like to be able to >> do is similar to an invention I made for the disk industry long >> ago, called Phase Margin Analysis. There is a brief description >> on my web page at >> http://pstca.com/patents.htm#phasemargin > Somewhere in my map of apps there is a HP appnote for doing the > same, to discs, intended for disc industry, back in the days. That may very well be a result of my invention, which occurred in 1970, was published in 1979, and was copied by IBM in the 1990's. But I have all the HP appnotes for disk. I don't recall any of them describing what I show above. Can you provide more information? [...] > The 53310A was a nice convenient tool at its time, but it's > performance isn't up to spec with modern times. It seems like HP > didn't pursue it into much deeper levels after its VXI > instruments, where as others went deeper. I'm not sure about this, but I don't think there is any later HP equipment that can approach what the 53310A does. But I can now match or beat it by orders of magnitude. This is sufficient for our current needs, but I will always be working on newer technology to break through the limits we now have. > Cheers, > Magnus Thanks, Mike From w1ksz at earthlink.net Sun Jun 21 21:24:25 2009 From: w1ksz at earthlink.net (Richard W. Solomon) Date: Sun, 21 Jun 2009 14:24:25 -0700 (GMT-07:00) Subject: [time-nuts] Thunderbolts for sale Message-ID: <10269879.1245619465545.JavaMail.root@mswamui-blood.atl.sa.earthlink.net> Did you receive my e-mail ? 73, Dick, W1KSZ -----Original Message----- >From: Brian Kirby >Sent: Jun 19, 2009 9:49 PM >To: Discussion of precise time and frequency measurement >Subject: [time-nuts] Thunderbolts for sale > >I will have two Trimble Thunderbolts GPSDO, that I will be selling. > >Both were bought thru the Time-Nuts purchases. There is nothing wrong >with these units, they are operational, and surplus to my needs. > >One unit comes with the Ault power supply and power connector. > >The second unit comes without a power supply and I will be furnishing a >pig-tailed power lead connector. > >I do not have pay-pal (sorry, I gave up on *bay...) and I can send COD. >I can only make this offer for the lower 48 of the United States. > >If you are interested, please contact me off this list. > >Brian Kirby - KD4FM > > > > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. From dave.mallery at gmail.com Sun Jun 21 22:12:35 2009 From: dave.mallery at gmail.com (Dave Mallery) Date: Sun, 21 Jun 2009 16:12:35 -0600 Subject: [time-nuts] Bad capacitors (was Volt-nuts cooperation?) In-Reply-To: References: Message-ID: <3010c9470906211512r73738824xf7c33fb2fc3f7757@mail.gmail.com> hi many thanks for the heads-up on the pg505 caps! they are supposed to be 350 ufd at 75 vdc. they are anything but. (goes back to mixing/matching caps...) dave On Sun, Jun 21, 2009 at 10:21 AM, Mark Sims wrote: > > The problems I saw were mostly hard failures in the caps > (opens/shorts/etc). These were in both power caps and signal caps. > > One lot that I saw was a group of 12 Mettler scales. 6 were used daily and > 6 were never used backup units. When the company shut down the operations > that used the scales, they were sold. All the used units worked fine. The > backup units all had capacitor problems. > > I also bought a lot of new-in-box Tektronix TM500 modules. Most wound up > having flakey capacitors. BTW, EVERY (new or used) Tek PG505 pulse > generator you will come across will have bad power supply filter caps... > unless they were replaced. > > > ---------------------------------------- > > > Does this happen even if the electrolytics are reformed before use? > _________________________________________________________________ > Lauren found her dream laptop. Find the PC that?s right for you. > http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dave Mallery, K5EN (ubuntu linux 9.04) HC31 Box 99E; Williamsburg, NM 87942 no gates... no windows! free at last! linux counter #64628 (since 1997) "People aren't as dumb as Microsoft needs them to be." --PJ, May 2007 From don.key at ntlworld.com Sun Jun 21 23:14:23 2009 From: don.key at ntlworld.com (Don Key) Date: Mon, 22 Jun 2009 00:14:23 +0100 Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In-Reply-To: <55232.44839.qm@web86304.mail.ird.yahoo.com> References: <000819CC0D4449478A872A2FEA60D58A@DBTOA000> <55232.44839.qm@web86304.mail.ird.yahoo.com> Message-ID: <04B4AD11A8FC49DAA586C95521161AEE@JimPC> Hi Dave Do you supply your DA1-4L distribution amp as a ready-built unit? Your PDF Technical manual says you do, but there are only prices for the kits on your ordering page. Cheers. Jim. ----- Original Message ----- From: "dave powis" To: "Discussion of precise time and frequency measurement" Sent: Sunday, June 21, 2009 5:34 PM Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp Hi Paul, Sounds a reasonable approach to me where an equal 2 way split is needed, and you already have adequate signal level available. May not be up to 'time-nuts' precision etc, but it is a practical method that will give what you need. If you ever need to remove one Rig, just remember to terminate the unused split output in 50R! However, when you get yourself an analyser, sig gen or counter that takes the 10MHz reference, then you will need a DA! Comeback to me (http://g4hup.com) or TAPR then! 73, Dave http://g4hup.com ________________________________ From: Paul Christensen To: Discussion of precise time and frequency measurement Sent: Sunday, 21 June, 2009 5:18:51 PM Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In the next couple weeks, I plan on distributing the output of my GPSDO to a pair of Icom transceivers. I've thought about using a DA like the TAPR TADD-1, but it seems that I can simply split the output of the +13 dBm GPSDO with a Z=50, 3dB equal power divider, that will yield an output of ~ +9.5 dBm to each transceiver. I can't foresee any port isolation issues that would make necessitate the use of the DA for this application and the 3 dB "hit" in level to each transceiver still seems reasonable for proper transceiver operation. Am I not considering something important? Also, I do not want to add any noise with such a distribution that would in any way destroy the excellent phase noise characteristics of my GPSDO. Thoughts? Paul, W9AC _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From g4hup at btinternet.com Sun Jun 21 23:38:58 2009 From: g4hup at btinternet.com (dave powis) Date: Sun, 21 Jun 2009 16:38:58 -0700 (PDT) Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In-Reply-To: <04B4AD11A8FC49DAA586C95521161AEE@JimPC> References: <000819CC0D4449478A872A2FEA60D58A@DBTOA000> <55232.44839.qm@web86304.mail.ird.yahoo.com> <04B4AD11A8FC49DAA586C95521161AEE@JimPC> Message-ID: <720079.15159.qm@web86306.mail.ird.yahoo.com> Hi Jim, Thanks for the enquiry. I do prefer to supply kits, as I am not a full time business, and need to work for a living! However, on request I do build units, so if that is what you want, I can quote for that. Cost for the DA1-4L assembled will depend on the connectors you want fitted - if you note from the page, I don't supply connectors with the kit, since some folks want BNC's to fit in their systems, while others want SMA's. Let me know what connector you are interested in, and where the finished unit is to be shipped to, and I'll put a quote together. Best 73, Dave, G4HUP ________________________________ From: Don Key To: Discussion of precise time and frequency measurement Sent: Monday, 22 June, 2009 12:14:23 AM Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp Hi Dave Do you supply your DA1-4L distribution amp as a ready-built unit? Your PDF Technical manual says you do, but there are only prices for the kits on your ordering page. Cheers. Jim. ----- Original Message ----- From: "dave powis" To: "Discussion of precise time and frequency measurement" Sent: Sunday, June 21, 2009 5:34 PM Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp Hi Paul, Sounds a reasonable approach to me where an equal 2 way split is needed, and you already have adequate signal level available. May not be up to 'time-nuts' precision etc, but it is a practical method that will give what you need. If you ever need to remove one Rig, just remember to terminate the unused split output in 50R! However, when you get yourself an analyser, sig gen or counter that takes the 10MHz reference, then you will need a DA! Comeback to me (http://g4hup.com) or TAPR then! 73, Dave http://g4hup.com ________________________________ From: Paul Christensen To: Discussion of precise time and frequency measurement Sent: Sunday, 21 June, 2009 5:18:51 PM Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In the next couple weeks, I plan on distributing the output of my GPSDO to a pair of Icom transceivers. I've thought about using a DA like the TAPR TADD-1, but it seems that I can simply split the output of the +13 dBm GPSDO with a Z=50, 3dB equal power divider, that will yield an output of ~ +9.5 dBm to each transceiver. I can't foresee any port isolation issues that would make necessitate the use of the DA for this application and the 3 dB "hit" in level to each transceiver still seems reasonable for proper transceiver operation. Am I not considering something important? Also, I do not want to add any noise with such a distribution that would in any way destroy the excellent phase noise characteristics of my GPSDO. Thoughts? Paul, W9AC _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From w7cs at theriver.com Sun Jun 21 23:53:44 2009 From: w7cs at theriver.com (Chuck Smallhouse) Date: Sun, 21 Jun 2009 16:53:44 -0700 Subject: [time-nuts] GPSDO 10 MHz Distribution Amp In-Reply-To: References: Message-ID: <20090621165346.F5FBD200@sj1-dm102.mta.everyone.net> At 04:39 PM 6/21/2009, time-nuts-request at febo.com wrote: >Send time-nuts mailing list submissions to > time-nuts at febo.com > >To subscribe or unsubscribe via the World Wide Web, visit > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >or, via email, send a message with subject or body 'help' to > time-nuts-request at febo.com >DEMI (Down East Microwave) has 10 MHz distibution amplifers for >sale, either in kit form or built and tested. The kits ( all the >parts, but sans connectors and enclosure) are only $25 and delivery was quick. Each output is driven by an ERA device and has a two stage low pass filter. I just put one together and it took about an hour. Damn some of SMD chip capacitors are really small ! But I'm proud that at my age (77) I can still solder with a steady hand. Chuck, W7CS >You can reach the person managing the list at > time-nuts-owner at febo.com > >When replying, please edit your Subject line so it is more specific >than "Re: Contents of time-nuts digest..." > > >Today's Topics: > > 1. Re: LF power supply noise (Mike Monett) > 2. Re: Thunderbolts for sale (Richard W. Solomon) > 3. Re: Bad capacitors (was Volt-nuts cooperation?) (Dave Mallery) > 4. Re: GPSDO 10 MHz Distribution Amp (Don Key) > 5. Re: GPSDO 10 MHz Distribution Amp (dave powis) > > >---------------------------------------------------------------------- > >Message: 1 >Date: Sun, 21 Jun 2009 15:27:54 -0300 >From: "Mike Monett" >Subject: Re: [time-nuts] LF power supply noise >To: "" >Message-ID: >Content-Type: text/plain; charset="iso-8859-1" > > > > Mike, > > [...] > > >> One of the reasons I was attracted to the 543310A was it could > >> display 14 digits of frequency in one second. Sine then, I have > >> figured a way to resolve 16 digits in one second, so that part of > >> the spec is no longer interesting. > > > As was described by J. J. Snyder in "An Ultra-High Resolution > > Frequency Meter" in the FCS 1981 (as available from IEEE UFFC) I > > assume, basically using the fact that adding more measurements in > > a dense time raises the degrees of freedom and allows for quicker > > interpolation. > > > Modern counters like HP 53131, HP 53132 as well as Pendulum CNT-90 > > or Fluke 6690 uses similar approaches. > > I can't find any copies that are not payware, but it is unlikely > there is any connection between the methods. > > Conventional averaging methods are limited by the exponential rise > in number of samples that are required to improve the SNR. The > measurement ends up taking too long, or the system drifts which > renders the mesurement useless. > > This provides an effective barrier to the amount of improvement > possible in SNR, and the available precision that is possible with > conventional technology. > > Binary Sampling works a completely different way. It ignores the > amplitude of the sample, and only records the direction of the > error. > > According to the Central Limit Theorem, the mean of Gaussian noise > is zero. This forces the Binary Sampler to converge on the true > value of the signal, and ignore the error caused by the amplitude of > the sample. > > This is a really big thing. The problem of using averaging to > improve sigma has existed for over 109 years. And nobody has been > able to solve it up till now. > > With a heterodyne sampling system, or conventional mixer technology, > the sample delta is the offset frequency divided by the square of > the reference frequency: > > Delta = Offset / Ref * Ref > > With a delta of 1Hz and reference of 1 MHz, the sample delta is > > 1 / (1e6)^2 = 1 / 1e12, > > or 1 picosecond. > > Since the Binary Sampler discards noise, the result is 1 picosecond > resolution in 1 second. > > I show this on my web site. The schematic for the measurement is > shown in Fig. 1 at > > http://pstca.com/sampler/design.htm > > A simple boxcar smoother is used to integrate the samples. The > result with different smoothing values is shown at > > http://pstca.com/sampler/smooth.htm > > A system with 18.38 ps rms jitter would require averaging 338 > waveforms to obtain 1ps rms jitter. With conventional sampling > technology, this would require 169 seconds, and the system would > probably drift during the measurement, rendering the measurement > invalid. > > So it is not possible to obtain this amount of improvement in this > system, and the measurement is impossible. > > The Binary Sampler gives 1ps resolution in 1 second. This is shown > in Fig. 4 at > > http://pstca.com/sampler/binsamp.htm > > No other system can achieve this performance. And anyone with > sufficient skill can duplicate this result at home. > > Extending this to higher frequency, it should be possible to obtain > a 1Hz offset at 100MHz with 1 uHz resolution. This gives > > 1 / (1e8)^2 = 1e-16 resolution in 1 second. > > I do not think any existing equipment from HP, Fluke, or Pendulum or > anyone else can come close to matching this level of performance. > > Also, existing technology must deal with noise and the averaging > problem. This eliminates much of the performance boundaries from > consideration. > > As a result, conventional technology cannot reach 1e-16 in one > second. > > > As being reported, such mechanisms does not fair well with ADEV > > calculations, and especially the overlapping variants of ADEV and > > den MDEV and TDEV which was inspired by that particular article, > > so using it twice forms unwanted filters. > > My approach delivers continuous samples. No missing or extra bits. > > >> The 543310A can do a single-shot time measurement with a > >> resolution of 200ps, and gets down to 1ps with averaging. The > >> HP5370B does 20ps single-shot, and will resolve 100fs with > >> averaging. But I have figured a way to measure 2ps single-shot, > >> and a bit better with averaging. So that part of the spec is not > >> so interesting any more. > > > I assume you really mean HP 53310A and not HP 543310A, even if > > your typing is consistent. The listed numbers is when weigthing in > > how various jitter sources combine upon averaging and should be > > considered a bit conservative. > > > By all means describe what you mean by 2 ps single-shot > > resolution. > > That will cure me of trying to type complex numbers when copy and > paste works so much better. But now I have to try and figure out > what your "weigthing" really means:) > > The 2ps single shot is dead straight conventional time-to-time > conversion. Nothing new there, except I think I have some new tricks > on stabilizing the circuits against drift, and providing a much > faster response to the zero-crossing at the end of the timing > interval. All these reduce the noise in the sampling process. > > But the real trick is applying the Binary Sampling technique to the > result. That allows a huge reduction in the noise from the sampling > process, and converges rapidly on a much more precise solution. > > >> The 543310A will display the phase and frequency changes in a PLL > >> step response. But you can get the frequency response just by > >> looking at the VCO DC error voltage. And if you look at the > >> voltage across the bottom capacitor in a type 3 loop, you get the > >> phase response. Here's a picture: > > >> | > >> --- C1 > >> --- > >> | > >> |----------O < - Phase Error > >> | | > >> --- C2 \ > >> --- / R1 > >> | \ > >> | | > >> --- --- > >> - - > > > You should recall that when HP built their line of analyzers, they > > where thinking "what can we make this cool ZDT core do?" rather > > than attempting to build the best analyzer for all responsens. > > I have a slightly different impression. I sold a lot of equipment to > Boisie, Idaho, and I used to make a lot of trips there in my Piper > Malibu, which was about the only realistic way of getting there from > San Jose: > > http://www.jetphotos.net/viewphoto.php?id=5874208&nseq=0 > > There was a lot of political infighting at Boisie involved in > development of new equipment. The winner pretty much had whatever > say he wanted in the direction, and he ignored the input from other > competent engineers. > > As a result, the equipment was limited by that individual's scope > and abilities. The result is much of HP's equipment suffered. > > One example is the 20ps single-shot resolution of the HP 5370B has > never been matched by any later equipment, as far as I know. A few > engineers at Boisie complained bitterly about the loss. > > >> So about the only thing left of interest is histograms of the > >> jitter. Unfortunately, the 543310A cannot store enough samples to > >> really make an interesting graph. What I would like to be able to > >> do is similar to an invention I made for the disk industry long > >> ago, called Phase Margin Analysis. There is a brief description > >> on my web page at > > >> http://pstca.com/patents.htm#phasemargin > > > Somewhere in my map of apps there is a HP appnote for doing the > > same, to discs, intended for disc industry, back in the days. > > That may very well be a result of my invention, which occurred in > 1970, was published in 1979, and was copied by IBM in the 1990's. > > But I have all the HP appnotes for disk. I don't recall any of them > describing what I show above. Can you provide more information? > > [...] > > > The 53310A was a nice convenient tool at its time, but it's > > performance isn't up to spec with modern times. It seems like HP > > didn't pursue it into much deeper levels after its VXI > > instruments, where as others went deeper. > > I'm not sure about this, but I don't think there is any later HP > equipment that can approach what the 53310A does. > > But I can now match or beat it by orders of magnitude. This is > sufficient for our current needs, but I will always be working on > newer technology to break through the limits we now have. > > > Cheers, > > Magnus > > Thanks, > > Mike > > > >------------------------------ > >Message: 2 >Date: Sun, 21 Jun 2009 14:24:25 -0700 (GMT-07:00) >From: "Richard W. Solomon" >Subject: Re: [time-nuts] Thunderbolts for sale >To: Discussion of precise time and frequency measurement > >Message-ID: > ><10269879.1245619465545.JavaMail.root at mswamui-blood.atl.sa.earthlink.net> > >Content-Type: text/plain; charset=UTF-8 > >Did you receive my e-mail ? > >73, Dick, W1KSZ > >-----Original Message----- > >From: Brian Kirby > >Sent: Jun 19, 2009 9:49 PM > >To: Discussion of precise time and frequency measurement > > >Subject: [time-nuts] Thunderbolts for sale > > > >I will have two Trimble Thunderbolts GPSDO, that I will be selling. > > > >Both were bought thru the Time-Nuts purchases. There is nothing wrong > >with these units, they are operational, and surplus to my needs. > > > >One unit comes with the Ault power supply and power connector. > > > >The second unit comes without a power supply and I will be furnishing a > >pig-tailed power lead connector. > > > >I do not have pay-pal (sorry, I gave up on *bay...) and I can send COD. > >I can only make this offer for the lower 48 of the United States. > > > >If you are interested, please contact me off this list. > > > >Brian Kirby - KD4FM > > > > > > > > > > > >_______________________________________________ > >time-nuts mailing list -- time-nuts at febo.com > >To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >and follow the instructions there. > > > > >------------------------------ > >Message: 3 >Date: Sun, 21 Jun 2009 16:12:35 -0600 >From: Dave Mallery >Subject: Re: [time-nuts] Bad capacitors (was Volt-nuts cooperation?) >To: Discussion of precise time and frequency measurement > >Message-ID: > <3010c9470906211512r73738824xf7c33fb2fc3f7757 at mail.gmail.com> >Content-Type: text/plain; charset=windows-1252 > >hi > >many thanks for the heads-up on the pg505 caps! > >they are supposed to be 350 ufd at 75 vdc. they are anything but. > >(goes back to mixing/matching caps...) > >dave > >On Sun, Jun 21, 2009 at 10:21 AM, Mark Sims wrote: > > > > > The problems I saw were mostly hard failures in the caps > > (opens/shorts/etc). These were in both power caps and signal caps. > > > > One lot that I saw was a group of 12 Mettler scales. 6 were used daily and > > 6 were never used backup units. When the company shut down the operations > > that used the scales, they were sold. All the used units worked > fine. The > > backup units all had capacitor problems. > > > > I also bought a lot of new-in-box Tektronix TM500 modules. Most wound up > > having flakey capacitors. BTW, EVERY (new or used) Tek PG505 pulse > > generator you will come across will have bad power supply filter caps... > > unless they were replaced. > > > > > > ---------------------------------------- > > > > > > Does this happen even if the electrolytics are reformed before use? > > _________________________________________________________________ > > Lauren found her dream laptop. Find the PC that?s right for you. > > http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > >-- >Dave Mallery, K5EN (ubuntu linux 9.04) >HC31 Box 99E; Williamsburg, NM 87942 > >no gates... > no windows! > free at last! > linux counter #64628 (since 1997) > >"People aren't as dumb as Microsoft needs them to be." >--PJ, May 2007 > > >------------------------------ > >Message: 4 >Date: Mon, 22 Jun 2009 00:14:23 +0100 >From: "Don Key" >Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp >To: "Discussion of precise time and frequency measurement" > >Message-ID: <04B4AD11A8FC49DAA586C95521161AEE at JimPC> >Content-Type: text/plain; format=flowed; charset="UTF-8"; > reply-type=original > >Hi Dave > >Do you supply your DA1-4L distribution amp as a ready-built unit? >Your PDF Technical manual says you do, but there are only prices for the >kits on your ordering page. >Cheers. > >Jim. >----- Original Message ----- >From: "dave powis" >To: "Discussion of precise time and frequency measurement" > >Sent: Sunday, June 21, 2009 5:34 PM >Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp > > >Hi Paul, > >Sounds a reasonable approach to me where an equal 2 way split is needed, and >you already have adequate signal level available. May not be up to >'time-nuts' precision etc, but it is a practical method that will give what >you need. If you ever need to remove one Rig, just remember to terminate >the unused split output in 50R! > >However, when you get yourself an analyser, sig gen or counter that takes >the 10MHz reference, then you will need a DA! Comeback to me >(http://g4hup.com) or TAPR then! > >73, >Dave > >http://g4hup.com > > > > >________________________________ >From: Paul Christensen >To: Discussion of precise time and frequency measurement > >Sent: Sunday, 21 June, 2009 5:18:51 PM >Subject: [time-nuts] GPSDO 10 MHz Distribution Amp > >In the next couple weeks, I plan on distributing the output of my GPSDO to a >pair of Icom transceivers. I've thought about using a DA like the TAPR >TADD-1, but it seems that I can simply split the output of the +13 dBm GPSDO >with a Z=50, 3dB equal power divider, that will yield an output of ~ +9.5 >dBm to each transceiver. > >I can't foresee any port isolation issues that would make necessitate the >use of the DA for this application and the 3 dB "hit" in level to each >transceiver still seems reasonable for proper transceiver operation. Am I >not considering something important? Also, I do not want to add any noise >with such a distribution that would in any way destroy the excellent phase >noise characteristics of my GPSDO. Thoughts? > >Paul, W9AC > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > > > > >------------------------------ > >Message: 5 >Date: Sun, 21 Jun 2009 16:38:58 -0700 (PDT) >From: dave powis >Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp >To: Discussion of precise time and frequency measurement > >Message-ID: <720079.15159.qm at web86306.mail.ird.yahoo.com> >Content-Type: text/plain; charset=utf-8 > >Hi Jim, > >Thanks for the enquiry. I do prefer to supply kits, as I am not a >full time business, and need to work for a living! However, on >request I do build units, so if that is what you want, I can quote for that. > >Cost for the DA1-4L assembled will depend on the connectors you want >fitted - if you note from the page, I don't supply connectors with >the kit, since some folks want BNC's to fit in their systems, while >others want SMA's. Let me know what connector you are interested >in, and where the finished unit is to be shipped to, and I'll put a >quote together. > >Best 73, >Dave, G4HUP > > > > >________________________________ >From: Don Key >To: Discussion of precise time and frequency measurement >Sent: Monday, 22 June, 2009 12:14:23 AM >Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp > >Hi Dave > >Do you supply your DA1-4L distribution amp as a ready-built unit? >Your PDF Technical manual says you do, but there are only prices for >the kits on your ordering page. >Cheers. > >Jim. >----- Original Message ----- From: "dave powis" >To: "Discussion of precise time and frequency measurement" > >Sent: Sunday, June 21, 2009 5:34 PM >Subject: Re: [time-nuts] GPSDO 10 MHz Distribution Amp > > >Hi Paul, > >Sounds a reasonable approach to me where an equal 2 way split is >needed, and you already have adequate signal level available. May >not be up to 'time-nuts' precision etc, but it is a practical method >that will give what you need. If you ever need to remove one Rig, >just remember to terminate the unused split output in 50R! > >However, when you get yourself an analyser, sig gen or counter that >takes the 10MHz reference, then you will need a DA! Comeback to me >(http://g4hup.com) or TAPR then! > >73, >Dave > >http://g4hup.com > > > > >________________________________ >From: Paul Christensen >To: Discussion of precise time and frequency measurement >Sent: Sunday, 21 June, 2009 5:18:51 PM >Subject: [time-nuts] GPSDO 10 MHz Distribution Amp > >In the next couple weeks, I plan on distributing the output of my >GPSDO to a pair of Icom transceivers. I've thought about using a DA >like the TAPR TADD-1, but it seems that I can simply split the >output of the +13 dBm GPSDO with a Z=50, 3dB equal power divider, >that will yield an output of ~ +9.5 dBm to each transceiver. > >I can't foresee any port isolation issues that would make >necessitate the use of the DA for this application and the 3 dB >"hit" in level to each transceiver still seems reasonable for proper >transceiver operation. Am I not considering something >important? Also, I do not want to add any noise with such a >distribution that would in any way destroy the excellent phase noise >characteristics of my GPSDO. Thoughts? > >Paul, W9AC > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > >------------------------------ > >_______________________________________________ >time-nuts mailing list >time-nuts at febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >End of time-nuts Digest, Vol 59, Issue 74 >***************************************** From holrum at hotmail.com Mon Jun 22 01:20:14 2009 From: holrum at hotmail.com (Mark Sims) Date: Mon, 22 Jun 2009 01:20:14 +0000 Subject: [time-nuts] Bad capacitors (was Volt-nuts cooperation?) In-Reply-To: References: Message-ID: I have rebuilt about 20 of the PG505's using 2200 uF 80V caps that a local surplus store had. They were about the same size as the original 350 uF caps and seem to work fine. They were the closest value that they had that could be installed in the original mounting holes. I ain't got no ripple in my pulses no more ;-) -------------------------------- hi many thanks for the heads-up on the pg505 caps! they are supposed to be 350 ufd at 75 vdc. they are anything but. _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From marc at msys.ch Mon Jun 22 08:11:24 2009 From: marc at msys.ch (Marc Balmer) Date: Mon, 22 Jun 2009 10:11:24 +0200 Subject: [time-nuts] Ideas for a long-wave receiver sought Message-ID: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> Hi I want to build a small, cheap, yet precise long-wave receiver which can be tuned from the computer in the 2KHz - 200 KHz range (the intended use is to receive various time signal stations). Does a chip for such a receiver exist? Should I take the SDR route? I designed a DCF77 receivers some years ago, but I need something more flexible (and a bit more modern...) - Marc Balmer From phk at phk.freebsd.dk Mon Jun 22 08:14:41 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 22 Jun 2009 08:14:41 +0000 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: Your message of "Mon, 22 Jun 2009 10:11:24 +0200." <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> Message-ID: <21393.1245658481@critter.freebsd.dk> In message <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6 at msys.ch>, Marc Balmer writes: >I want to build a small, cheap, yet precise long-wave receiver which >can be >tuned from the computer in the 2KHz - 200 KHz range (the intended use >is to receive various time signal stations). > >Does a chip for such a receiver exist? Should I take the SDR route? >I designed a DCF77 receivers some years ago, but I need something >more flexible (and a bit more modern...) Go SDR. There are ARM7 chips now that have sufficient ADC quality to do the job. See for instance: http://phk.freebsd.dk/AducLoran Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From marc at msys.ch Mon Jun 22 09:30:56 2009 From: marc at msys.ch (Marc Balmer) Date: Mon, 22 Jun 2009 11:30:56 +0200 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <21393.1245658481@critter.freebsd.dk> References: <21393.1245658481@critter.freebsd.dk> Message-ID: <70D1E333-26C4-4068-BFAC-30D689BBF3D1@msys.ch> Am 22.06.2009 um 10:14 schrieb Poul-Henning Kamp: > In message <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6 at msys.ch>, Marc > Balmer writes: > >> I want to build a small, cheap, yet precise long-wave receiver which >> can be >> tuned from the computer in the 2KHz - 200 KHz range (the intended use >> is to receive various time signal stations). >> >> Does a chip for such a receiver exist? Should I take the SDR route? >> I designed a DCF77 receivers some years ago, but I need something >> more flexible (and a bit more modern...) > > Go SDR. > > There are ARM7 chips now that have sufficient ADC quality to do the > job. Ok, thanks. I happen to have some Overp Earth boards, OMAP 3503 Application Processor with ARM Cortex-A8 CPU, do you think these will handle the job? (runnin at 600 MHz). They say it makes up 1200 dhrytsone mips (www.gumstix.com) > > See for instance: http://phk.freebsd.dk/AducLoran Thanks for the pointer, I already found that, nice work! - Marc > > Poul-Henning > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk at FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by > incompetence. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From phk at phk.freebsd.dk Mon Jun 22 09:46:39 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 22 Jun 2009 09:46:39 +0000 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: Your message of "Mon, 22 Jun 2009 11:30:56 +0200." <70D1E333-26C4-4068-BFAC-30D689BBF3D1@msys.ch> Message-ID: <28786.1245663999@critter.freebsd.dk> In message <70D1E333-26C4-4068-BFAC-30D689BBF3D1 at msys.ch>, Marc Balmer writes: >Ok, thanks. I happen to have some Overp Earth boards, OMAP 3503 >Application Processor with ARM Cortex-A8 CPU, do you think these >will handle the job? (runnin at 600 MHz). They say it makes up 1200 >dhrytsone mips It's more a matter of what their ADC can do... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From marc at msys.ch Mon Jun 22 10:07:34 2009 From: marc at msys.ch (Marc Balmer) Date: Mon, 22 Jun 2009 12:07:34 +0200 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <28786.1245663999@critter.freebsd.dk> References: <28786.1245663999@critter.freebsd.dk> Message-ID: <0587CB86-96EF-4660-9FBE-8C1D1FDFBAFB@msys.ch> Am 22.06.2009 um 11:46 schrieb Poul-Henning Kamp: > In message <70D1E333-26C4-4068-BFAC-30D689BBF3D1 at msys.ch>, Marc > Balmer writes: > >> Ok, thanks. I happen to have some Overp Earth boards, OMAP 3503 >> Application Processor with ARM Cortex-A8 CPU, do you think these >> will handle the job? (runnin at 600 MHz). They say it makes up 1200 >> dhrytsone mips > > It's more a matter of what their ADC can do... unfortunately it's "only" a TI TPS65950 which has only an audio codec, the ADC doing 48kHz max. From phk at phk.freebsd.dk Mon Jun 22 10:16:18 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 22 Jun 2009 10:16:18 +0000 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: Your message of "Mon, 22 Jun 2009 12:07:34 +0200." <0587CB86-96EF-4660-9FBE-8C1D1FDFBAFB@msys.ch> Message-ID: <33349.1245665778@critter.freebsd.dk> In message <0587CB86-96EF-4660-9FBE-8C1D1FDFBAFB at msys.ch>, Marc Balmer writes: >unfortunately it's "only" a TI TPS65950 which has only an audio codec, >the ADC doing 48kHz max. That's still usable, you could for instance use a "DRM" frontend like the "pappradio" There are some links here: http://www.drmradio.dk/Byggesaet og konvertere-da.htm Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From ewkehren at aol.com Mon Jun 22 11:35:11 2009 From: ewkehren at aol.com (ewkehren at aol.com) Date: Mon, 22 Jun 2009 07:35:11 -0400 Subject: [time-nuts] Thunderbolts for sale In-Reply-To: <10269879.1245619465545.JavaMail.root@mswamui-blood.atl.sa.earthlink.net> References: <10269879.1245619465545.JavaMail.root@mswamui-blood.atl.sa.earthlink.net> Message-ID: <8CBC144A316FA5C-1684-506D@webmail-de11.sysops.aol.com> Did you receive my e-mail? Same question WB5MZJ Bert -----Original Message----- From: Richard W. Solomon To: Discussion of precise time and frequency measurement Sent: Sun, Jun 21, 2009 5:24 pm Subject: Re: [time-nuts] Thunderbolts for sale Did you receive my e-mail ? 73, Dick, W1KSZ -----Original Message----- >From: Brian Kirby >Sent: Jun 19, 2009 9:49 PM >To: Discussion of precise time and frequency measurement >Subject: [time-nuts] Thunderbolts for sale > >I will have two Trimble Thunderbolts GPSDO, that I will be selling. > >Both were bought thru the Time-Nuts purchases. There is nothing wrong >with these units, they are operational, and surplus to my needs. > >One unit comes with the Ault power supply and power connector. > >The second unit comes without a power supply and I will be furnishing a >pig-tailed power lead connector. > >I do not have pay-pal (sorry, I gave up on *bay...) and I can send COD. >I can only make this offer for the lower 48 of the United States. > >If you are interested, please contact me off this list. > >Brian Kirby - KD4FM > > > > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From asmagal at fc.up.pt Mon Jun 22 11:58:17 2009 From: asmagal at fc.up.pt (asmagal at fc.up.pt) Date: Mon, 22 Jun 2009 13:58:17 +0200 Subject: [time-nuts] Austron 2000C Message-ID: <20090622135817.jrnnqunkis8ow4k8@webmail.fc.up.pt> Greetings to all members. I would like to purchase the following parts for the Austron 2000C LORAN-C receiver: -ASSEMBLY PCB ASSY GRP DIVIDER, ASSY NO 10397137; -ASSEMBLY PCB ASSY PHASE CODE, ASSY NO 10396936. The above parts could eventually have been produced by Tracor, Inc. from Austin, TX, also. Any clue would be very much appreciated. Antonio/CT1TE. ------------------------------------------------------------------------- A FCUP utiliza o sistema open source de webmail Horde/IMP (www.horde.org) Visite: http://www.fc.up.pt/ http://info.fc.up.pt/ From brooke at pacific.net Mon Jun 22 14:18:01 2009 From: brooke at pacific.net (Brooke Clarke) Date: Mon, 22 Jun 2009 07:18:01 -0700 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> References: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> Message-ID: <4A3F9299.9080505@pacific.net> Hi Marc: The SDR-IQ has the ability to record everything between 500 Hz and 190 kHz when used with a fast enough PC. This is the best of the SDR series for use below 200 kHz. It can be used with SpectraVue or Winrad. Works with I2PHD WINRAD, SM5BSZ LINRAD, HOKA and DRM software. See: http://www.rfspace.com/SDR-IQ.html http://groups.yahoo.com/group/SDR-IQ/ Have Fun, Brooke Clarke http://www.prc68.com Marc Balmer wrote: > Hi > > I want to build a small, cheap, yet precise long-wave receiver which can be > tuned from the computer in the 2KHz - 200 KHz range (the intended use > is to receive various time signal stations). > > Does a chip for such a receiver exist? Should I take the SDR route? > I designed a DCF77 receivers some years ago, but I need something > more flexible (and a bit more modern...) > > - Marc Balmer > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From brooke at pacific.net Mon Jun 22 14:24:54 2009 From: brooke at pacific.net (Brooke Clarke) Date: Mon, 22 Jun 2009 07:24:54 -0700 Subject: [time-nuts] SDR-IP with 10 MHz Cesium and 1 PPS Input Message-ID: <4A3F9436.2050806@pacific.net> Hi: RF Space is developing the SDR-IP (Internet Protocol) receiver that has options for an external 10 MHz Cesium reference as well as 1 PPS input to allow multiple receivers to work as RADAR sets (using FM radio broadcast transmitters) or for radio astronomy. http://www.rfspace.com/SDR-IP.html http://groups.yahoo.com/group/SDR-IP/ The existing SDR-IQ and SDR-14 are now being used in a number of space related activities, see: http://www.rfspace.com/BLOG/BLOG.html -- Have Fun, Brooke Clarke http://www.prc68.com From marc at msys.ch Mon Jun 22 14:41:12 2009 From: marc at msys.ch (Marc Balmer) Date: Mon, 22 Jun 2009 16:41:12 +0200 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <4A3F9299.9080505@pacific.net> References: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> <4A3F9299.9080505@pacific.net> Message-ID: <2EA6313A-99DC-4017-9ED9-31D83E9FA804@msys.ch> Am 22.06.2009 um 16:18 schrieb Brooke Clarke: > Hi Marc: > > The SDR-IQ has the ability to record everything between 500 Hz and > 190 kHz when used with a fast enough PC. This is the best of the > SDR series for use below 200 kHz. > It can be used with SpectraVue or Winrad. > Works with I2PHD WINRAD, SM5BSZ LINRAD, HOKA and DRM software. See: > http://www.rfspace.com/SDR-IQ.html > http://groups.yahoo.com/group/SDR-IQ/ > very nice, indeed, although it does not fit my definition of cheap. but then I'd like to get one of these, are the specs and docs open? I am not using Windows but rather Unix (BSD) > Have Fun, > > Brooke Clarke > http://www.prc68.com > > Marc Balmer wrote: >> Hi >> I want to build a small, cheap, yet precise long-wave receiver >> which can be >> tuned from the computer in the 2KHz - 200 KHz range (the intended use >> is to receive various time signal stations). >> Does a chip for such a receiver exist? Should I take the SDR route? >> I designed a DCF77 receivers some years ago, but I need something >> more flexible (and a bit more modern...) >> - Marc Balmer >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From phk at phk.freebsd.dk Mon Jun 22 15:07:07 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 22 Jun 2009 15:07:07 +0000 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: Your message of "Mon, 22 Jun 2009 07:18:01 MST." <4A3F9299.9080505@pacific.net> Message-ID: <5964.1245683227@critter.freebsd.dk> In message <4A3F9299.9080505 at pacific.net>, Brooke Clarke writes: >The SDR-IQ has the ability to record everything between 500 Hz and 190 kHz when >used with a fast enough PC. This is the best of the SDR series for use below >200 kHz. I have looked at that earlier, but it does not look like it is feasible to lock its clock to an atomic reference :-/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From james.p.lux at jpl.nasa.gov Mon Jun 22 16:13:01 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Mon, 22 Jun 2009 09:13:01 -0700 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <4A3F9299.9080505@pacific.net> References: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> <4A3F9299.9080505@pacific.net> Message-ID: 200kHz is a bit tricky for the top end.. That probably puts the standard music recording A/D out of the picture (although they have very high performance A/Ds in them, and because of large production volume, they're relatively inexpensive). Almost any PC these days has enough processor to take a 400 ksps stream of samples and filter/decimate it. Maybe the boards from the HPSDR folks might serve? Do you need continuous stream of samples? One of the eval boards for high performance A/Ds with a USB might work for you, but last time I checked, they were more oriented to "capture a buffer, then analyze" sorts of approaches. Your best long range approach might be to use a high quality A/D with a small FPGA behind it that implements a digital down converter, feeding the (lower rate after downconversion/filtering) samples through USB to an application like DL4YHF's spectrum lab. DL4YHF is very interested in VLF receiving, and he might have good ideas on inexpensive approaches. http://freenet-homepage.de/dl4yhf/spectra1.html > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Brooke Clarke > Sent: Monday, June 22, 2009 7:18 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Ideas for a long-wave receiver sought > > Hi Marc: > > The SDR-IQ has the ability to record everything between 500 > Hz and 190 kHz when used with a fast enough PC. This is the > best of the SDR series for use below 200 kHz. > It can be used with SpectraVue or Winrad. > Works with I2PHD WINRAD, SM5BSZ LINRAD, HOKA and DRM software. See: > http://www.rfspace.com/SDR-IQ.html > http://groups.yahoo.com/group/SDR-IQ/ > > Have Fun, > > Brooke Clarke > http://www.prc68.com > > Marc Balmer wrote: > > Hi > > > > I want to build a small, cheap, yet precise long-wave > receiver which > > can be tuned from the computer in the 2KHz - 200 KHz range (the > > intended use is to receive various time signal stations). > > > > Does a chip for such a receiver exist? Should I take the SDR route? > > I designed a DCF77 receivers some years ago, but I need > something more > > flexible (and a bit more modern...) > > > > - Marc Balmer From brooke at pacific.net Mon Jun 22 16:41:06 2009 From: brooke at pacific.net (Brooke Clarke) Date: Mon, 22 Jun 2009 09:41:06 -0700 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <5964.1245683227@critter.freebsd.dk> References: <5964.1245683227@critter.freebsd.dk> Message-ID: <4A3FB422.5000709@pacific.net> Hi Poul: The SDR-IQ has holes in the PCB for an SMA jack and there's a jumper/resistor used to select either the on board 66 MHz crystal oscillator or the external source. See: http://www.prc68.com/I/Bats.shtml#SDRIQ Have Fun, Brooke Clarke http://www.prc68.com Poul-Henning Kamp wrote: > In message <4A3F9299.9080505 at pacific.net>, Brooke Clarke writes: > >> The SDR-IQ has the ability to record everything between 500 Hz and 190 kHz when >> used with a fast enough PC. This is the best of the SDR series for use below >> 200 kHz. > > I have looked at that earlier, but it does not look like it is feasible > to lock its clock to an atomic reference :-/ > From mpfahmie at lbl.gov Mon Jun 22 16:49:26 2009 From: mpfahmie at lbl.gov (Mike Fahmie) Date: Mon, 22 Jun 2009 09:49:26 -0700 Subject: [time-nuts] ARRL FMT - addendum In-Reply-To: <4.3.2.7.2.20070307094203.031a4b50@popper.lbl.gov> References: <45EED4BC.9070301@alum.wpi.edu> <4.3.2.7.2.20070306112910.0345b370@popper.lbl.gov> <001801c76011$cd5b4610$0200a8c0@BASE1> <5D4F7C8593366B4BADD5A821D00EBAA09BD21F@exchange15.fed.cclrc.ac.uk> <5D4F7C8593366B4BADD5A821D00EBAA09BD228@exchange15.fed.cclrc.ac.uk> <001801c76011$cd5b4610$0200a8c0@BASE1> <4.3.2.7.2.20070306112910.0345b370@popper.lbl.gov> Message-ID: <4.3.2.7.2.20090622094448.039a0930@popper.lbl.gov> A couple of details that might help you avoid confusion in next weeks ARRL FMT; 1.) The CW ID transmissions will be on the carrier frequency. 2.) Tone transmissions will be on the Lower Side Band. -Mike- WA6ZTY From jmiles at pop.net Tue Jun 23 04:56:59 2009 From: jmiles at pop.net (John Miles) Date: Mon, 22 Jun 2009 21:56:59 -0700 Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: Message-ID: It's not necessarily inexpensive, but here's one data point: an EVAL-AD7760 board is $150, and a Nexys2 FPGA board is $129. This combination can acquire DC-1 MHz with 100 dB SNR and 120 dB SFDR. There is no need for a hardware or FPGA-based DDC, as any modern PC can do host-based processing at these rates without breaking a sweat. In the setup I have been playing with, the FPGA is used only to transfer the AD7760's output to the USB 2.0 chip. With a 16 KB block-RAM FIFO in the FPGA and overlapped reads from the CyUSB driver, my test app has run for 2-3 days at 10 MBytes/sec without missing any samples. At 20 MBytes/sec, sending every 32-bit sample twice as a test, the FIFO overruns every couple of hours. Considering that you can spend $279 on a high-end sound card without trying very hard, the AD7760-based USB digitizer isn't too unreasonable, at least for single-channel applications. I'm still debating whether to spin a PCB that'll put the FX2 USB chip, FPGA, and AD7760 on one board... it's tempting, because I'd really like a two-channel digitizer, but it won't necessarily be much cheaper than the Nexys2/EVAL-AD7760 combo. The Nexys2 is a real bargain. I'm not quite ready to call the Verilog and ADC API code "done," although anyone who wants to play with it is welcome to it, just write me offline. TI also has a new 24-bit sigma-delta ADC called the ADS1675 that digitizes at 4 MS/s and uses about half the power of the AD7760. You can buy the chips from DigiKey but there appears to be no official evaluation board yet. It's hard to compare the specs on an apples-to-apples basis, but my impression is that the overall performance isn't too far behind the AD7760 at 2.5 MSPS. Re: the SDR-IQ, yes, it comes with a public interface spec. It's based on ASCP (Amateur Station Control Protocol), which I'm not too familiar with. Great little box, usable as a general-purpose digitizer for narrowband HF applications that don't need to go all the way down to DC. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Lux, James P > Sent: Monday, June 22, 2009 9:13 AM > To: brooke at pacific.net; Discussion of precise time andfrequency > measurement > Subject: Re: [time-nuts] Ideas for a long-wave receiver sought > > > 200kHz is a bit tricky for the top end.. That probably puts the > standard music recording A/D out of the picture (although they > have very high performance A/Ds in them, and because of large > production volume, they're relatively inexpensive). > > Almost any PC these days has enough processor to take a 400 ksps > stream of samples and filter/decimate it. > Maybe the boards from the HPSDR folks might serve? > > Do you need continuous stream of samples? One of the eval boards > for high performance A/Ds with a USB might work for you, but last > time I checked, they were more oriented to "capture a buffer, > then analyze" sorts of approaches. > > Your best long range approach might be to use a high quality A/D > with a small FPGA behind it that implements a digital down > converter, feeding the (lower rate after > downconversion/filtering) samples through USB to an application > like DL4YHF's spectrum lab. DL4YHF is very interested in VLF > receiving, and he might have good ideas on inexpensive approaches. > http://freenet-homepage.de/dl4yhf/spectra1.html > > > > > > -----Original Message----- > > From: time-nuts-bounces at febo.com > > [mailto:time-nuts-bounces at febo.com] On Behalf Of Brooke Clarke > > Sent: Monday, June 22, 2009 7:18 AM > > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] Ideas for a long-wave receiver sought > > > > Hi Marc: > > > > The SDR-IQ has the ability to record everything between 500 > > Hz and 190 kHz when used with a fast enough PC. This is the > > best of the SDR series for use below 200 kHz. > > It can be used with SpectraVue or Winrad. > > Works with I2PHD WINRAD, SM5BSZ LINRAD, HOKA and DRM software. See: > > http://www.rfspace.com/SDR-IQ.html > > http://groups.yahoo.com/group/SDR-IQ/ > > > > Have Fun, > > > > Brooke Clarke > > http://www.prc68.com > > > > Marc Balmer wrote: > > > Hi > > > > > > I want to build a small, cheap, yet precise long-wave > > receiver which > > > can be tuned from the computer in the 2KHz - 200 KHz range (the > > > intended use is to receive various time signal stations). > > > > > > Does a chip for such a receiver exist? Should I take the SDR route? > > > I designed a DCF77 receivers some years ago, but I need > > something more > > > flexible (and a bit more modern...) > > > > > > - Marc Balmer > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From david.partridge at dsl.pipex.com Tue Jun 23 08:28:44 2009 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Tue, 23 Jun 2009 09:28:44 +0100 Subject: [time-nuts] TNC connectors Message-ID: <97A430416D9546F0BED1FCE6D3656699@APOLLO> I'm thinking of buying a Panasonic VIC100 timing antenna with a 50 ohm TNC connector (I assume) from fluke.l on eBay, as the room I use for my den has moved to one without a view to the south, so I can't use the puck antenna mounted just outside the window any more. The T-Bolt manual recommends 75 ohm coax, so will a 75 ohm TNC mate with a 50 ohm TNC without problems? Though I suppose for a short run of cable, 50 ohm will be OK? PS Where do you get the (1" diameter?) threaded poles these antennas screw onto? Cheers David Partridge From df6jb at ulrich-bangert.de Tue Jun 23 09:28:35 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Tue, 23 Jun 2009 11:28:35 +0200 Subject: [time-nuts] Introduction of Z38XX Message-ID: Gents, perhaps you have read that since a few days I am the owner of a Z3805 bought on eBAy from fluke.I. The other day a friend of mine visited me and brought his GPSCON with him to test it on my Z3805. As fluke.I had pointed out, the GPSCON would work with the Z3805 but it would not work really satisfying. The reason is that the Z3801 has a 6 channel receiver and the Z3816 has a 8 channel receiver, so GPSCON is simply not prepared to read more than 8 sat data sets from the Z3805's status screen (which has a 12 channel receiver). In addition, because the Z3805's status screen uses more lines for the display of the additional sat data sets GPSCON will miss the last three lines of the z3805's status screen. This in conjunction with some other things encouraged me me to write a z3805 tool of my own named Z38XX. Of course it will handle z3801s and z3816s as well. It is far from being complete but you can get a good impression of it by downloading it from the usual place http://www.ulrich-bangert.de/html/downloads.html Z38XX talks to the Z3801/5/16 with a exact 10 s time base which means the PPS TI delivered can be used for the computation of Allan deviation (and other measures) of the internal phase comparator with a Tau0 = 10 s (which is done internally in Z38XX similar as in Lady Heather). The sat's horizont line in the Azimuth / Elevation chart will look strange in the first hours after program start. Give it some days until it looks as attched or even better. Have fun Ulrich Bangert www.ulrich-bangert.de Ortholzer Weg 1 27243 Gross Ippener -------------- next part -------------- A non-text attachment was scrubbed... Name: PChart.pdf Type: application/pdf Size: 7816 bytes Desc: not available URL: From dave at uk-ar.co.uk Tue Jun 23 09:59:00 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Tue, 23 Jun 2009 10:59:00 +0100 Subject: [time-nuts] TNC connectors In-Reply-To: Message-ID: > Message: 9 > Date: Tue, 23 Jun 2009 09:28:44 +0100 > From: "David C. Partridge" > Subject: [time-nuts] TNC connectors > > I'm thinking of buying a Panasonic VIC100 timing antenna with > a 50 ohm TNC connector (I assume) from fluke.l on eBay, as the room I use > for my den has moved to one without a view to the south, so I can't use the > puck antenna mounted just outside the window any more. > > The T-Bolt manual recommends 75 ohm coax, so will a 75 ohm > TNC mate with a 50 ohm TNC without problems? Though I suppose for a short > run of cable, 50 ohm will be OK? > > PS Where do you get the (1" diameter?) threaded poles these > antennas screw onto? > > Cheers > David Partridge Hi Again David. Hope all's still well with that DMM... According to Wikipedia, a 75r TNC will mate OK with a 50r version. http://en.wikipedia.org/wiki/TNC_connector However, it's years since I saw a 75r version, so I don't know for sure. Doing that with BNC's will lead to a flaky connection, as the centre pin on the 75r ones is much smaller. The other way round (50r plug into 75r socket) will damage the socket. As TNC's are very similar to BNC's ??? However..... Scratching about the www for a minute or two... a 75r TNC data sheet is here. http://www.hubersuhner.com/mozilla/hs-p-rf-con-gr-series-tnc75-td_en.pdf and the 50r version is here. http://www.hubersuhner.com/mozilla/hs-p-rf-con-gr-series-tnc50-td_en.pdf The centre pin's are very similar it seems! Unfortunately, if you have to source one from these people it'll cost an arm and a leg. We used to be able to ring up the distribution centre in Bicester, then run over to get some parts at good cost/time etc, now even we have to go through a third party in Kent (I think is where they are/were) who hold no stock and have very long lead times, and even higher costs! I'd be tempted to just fit a 50r TNC plug (common enough) and go with that... I'm also looking at a Thunderbolt, but mainly to get a reliable 1PPS feed for a NTP server that I've yet to figure out how to get going. (Just not enough of the right sort of time to figure out this sort of stuff) After I blew up the only GPS RX I had with a 1PPS output, due to a (commercially built, with no crowbar) PSU failure. If I could use the 10MHz output for a receiver LO reference, and soundcard clock locking too, that would be a bonus. Not looked at a TB manual yet (are they downloadable?) but it does have a 'F' connector on the front from what I've seen of the pictures, and those are generally used with 75r solid centre conductor coax. 50r solid centre conductor cable can be used with F's too however that I do know. But at 1500MHz any matching problem may be an issue, F's are generally only rated up to 1GHz anyway, though "usable" to several GHz, they say... Does anyone know what the actual design input Z of the TB's GPS RX is? As connectors, they are not much better/worse than "UHF" types. Mechanically poor is an understatement, and ideally they need the correct torque to secure them to be reliable. (In a past life, I briefly worked for a Cable TV equipment company.) In any case, there will be less of a problem at the antenna end with a mismatch, than at the RX end of the cable. Source mismatches are much less troublesome than load mismatches, when a long cable is used, so if indeed it needs to use 75r, then that would be best. "Long" in this context, being relative in terms of signal wavelength. At 1500MHz the wavelength is only some 0.2m (in free air too, it will be even shorter in the cable) so just about any practical physical length will appear "long". At the moment, I'm up to my eyes in dead multi kW RF amps, and creaky firmware in other (unrelated) products, that & friends/family are continuing to keep me very busy with various PC woes, plus a possible trip to the US is on the cards, as a result of one of the multi kW amp failures. It never ends!... Regards to All. Dave B. PS: 1" 'Threaded' poles? A marine chandlers perhaps? Or just "wing it" with a cheap ally' TV type pole, and a bit of creativity with some silicone rubber! (The non corrosive stuff) From GandalfG8 at aol.com Tue Jun 23 10:00:49 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 23 Jun 2009 06:00:49 EDT Subject: [time-nuts] TNC connectors Message-ID: In a message dated 23/06/2009 09:29:38 GMT Daylight Time, david.partridge at dsl.pipex.com writes: The T-Bolt manual recommends 75 ohm coax, so will a 75 ohm TNC mate with a 50 ohm TNC without problems? Though I suppose for a short run of cable, 50 ohm will be OK? --------------------- Hi David There's been some previous discussion on this, perhaps an archive search will throw up past comments, and probably with usual Time-Nuts overkill:-). According to the manual the Thunderbolt antenna input impedance is 50ohms, despite their using an F connector, but they recommend using 75 ohm cable on the basis that it tends to have lower loss for a given size. Unless you're planning on really long runs I'd suggest just sticking with 50 ohm cable and connectors. I've got a couple of commercial antennas that come with predefined lengths of cable, 20 metres if I remember correctly, and these use RG58. I'm not sure if you'll get a TNC to F type adapter anyway, so you might have to revert to BNC on the cable at the Thunderbolt end. The mounting pole thread seems to be fairly standard but not sure on availability of threaded poles. One option would be a stub mounting plate as sold for marine use, one current ebay item for example is 250430681103, and a further search in the marine section might prove useful. regards Nigel GM8PZR From GandalfG8 at aol.com Tue Jun 23 10:11:36 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 23 Jun 2009 06:11:36 EDT Subject: [time-nuts] TNC connectors Message-ID: In a message dated 23/06/2009 11:00:13 GMT Daylight Time, dave at uk-ar.co.uk writes: However, it's years since I saw a 75r version, so I don't know for sure. Doing that with BNC's will lead to a flaky connection, as the centre pin on the 75r ones is much smaller. The other way round (50r plug into 75r socket) will damage the socket. As TNC's are very similar to BNC's ??? ---------------- This belief about BNC connectors seems to be an "urban myth", although admittedly one that I shared for many years. Whether or not it has been true at some time in the past, or of some manufacturers, I don't know but the following is a current quote from Amphenol........ --------------- Two distinct types of 75 ? BNCs are available, and both mate with each other and with 50 ? BNCs. Type 1 is designated 75 ? BNC-T1 and provides constant 75 ? performance with low VSWR DC ? 4 GHz. Type 2 is designated 75 ? BNC-T2 and is usable with low reflection DC - 1 GHz. For applications above 1 GHz, Type 1 is recommended. -------------------- The full text of this can be found at.... _http://www.amphenolconnex.com/products/bnc.asp_ (http://www.amphenolconnex.com/products/bnc.asp) and I've seen similar comments from other manufacturers. regards Nigel GM8PZR From david.partridge at dsl.pipex.com Tue Jun 23 10:37:39 2009 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Tue, 23 Jun 2009 11:37:39 +0100 Subject: [time-nuts] TNC connectors In-Reply-To: References: Message-ID: <1EB69185ABD1478AB2F4CFA65A540BFC@APOLLO> Hi Dave, The Solartron 7081 is very happy and so am I :-). Thanks yet again for all your help. Re: different sized centre pins - I know that's true of "N" type connectors, - you really don't want to push an N type male 50R into an N type female 75R connector. However I'm pretty sure that it doesn't apply to BNC - just wasn't sure about TNC. Dave From normn3ykf at stny.rr.com Tue Jun 23 10:54:24 2009 From: normn3ykf at stny.rr.com (Norman J McSweyn) Date: Tue, 23 Jun 2009 06:54:24 -0400 Subject: [time-nuts] TNC connectors In-Reply-To: <1EB69185ABD1478AB2F4CFA65A540BFC@APOLLO> References: <1EB69185ABD1478AB2F4CFA65A540BFC@APOLLO> Message-ID: <4A40B460.3000906@stny.rr.com> David, I used a piece of pvc conduit to mount the antenna. It fits in the vic-100's mounting skirt. If it does not have a mounting skirt, perhaps use a flange and drill the appropriate holes, apply RTV (or your favorite sealant!). Norm (The divider board is working like a charm!! Even impressed the heck out of my new GF!!! GEEEEKKKKKK!!!) David C. Partridge wrote: > Hi Dave, > > The Solartron 7081 is very happy and so am I :-). Thanks yet again for all > your help. > > Re: different sized centre pins - I know that's true of "N" type connectors, > - you really don't want to push an N type male 50R into an N type female > 75R connector. However I'm pretty sure that it doesn't apply to BNC - just > wasn't sure about TNC. > > Dave > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From david.partridge at dsl.pipex.com Tue Jun 23 11:10:17 2009 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Tue, 23 Jun 2009 12:10:17 +0100 Subject: [time-nuts] TNC connectors In-Reply-To: <4A40B460.3000906@stny.rr.com> References: <1EB69185ABD1478AB2F4CFA65A540BFC@APOLLO> <4A40B460.3000906@stny.rr.com> Message-ID: <703B310589984AA8BF42B21157DF696D@APOLLO> Norman, PVC conduit sounds like a good solution. I'm delighted to hear the frequency divider board is performing good service. I was rather surprised when there was insufficient interest to justify getting a further batch of boards made up. I'm pretty sure it would out-perform any micro based solution (no disrespect to the TAPR board intended) in terms of jitter etc. especially if you used thin film resistors instead of thick film in the clock circuit, but don't have the test equipment to measure that. I wonder if anyone did get round to measuring how good or bad it was - I did try (with a lot of help from Bruce) to design it to minimise that sort of problem. Dave -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Norman J McSweyn Sent: 23 June 2009 11:54 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] TNC connectors David, I used a piece of pvc conduit to mount the antenna. It fits in the vic-100's mounting skirt. If it does not have a mounting skirt, perhaps use a flange and drill the appropriate holes, apply RTV (or your favorite sealant!). Norm (The divider board is working like a charm!! Even impressed the heck out of my new GF!!! GEEEEKKKKKK!!!) David C. Partridge wrote: > Hi Dave, > > The Solartron 7081 is very happy and so am I :-). Thanks yet again > for all your help. > > Re: different sized centre pins - I know that's true of "N" type > connectors, > - you really don't want to push an N type male 50R into an N type female > 75R connector. However I'm pretty sure that it doesn't apply to BNC - just > wasn't sure about TNC. > > Dave > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From cfharris at erols.com Tue Jun 23 11:54:02 2009 From: cfharris at erols.com (Chuck Harris) Date: Tue, 23 Jun 2009 07:54:02 -0400 Subject: [time-nuts] TNC connectors In-Reply-To: References: Message-ID: <4A40C25A.7080403@erols.com> Dave Baxter wrote: > Doing that with BNC's will lead to a flaky connection, as the centre pin > on the 75r ones is much smaller. The other way round (50r plug into 75r > socket) will damage the socket. As TNC's are very similar to BNC's ??? You are thinking of the incompatibility between 50 ohm and 75 ohm *N* connectors. 75 ohm BNC are use the same center pin hardware as 50 ohm BNC. The only difference is in the white plastic (teflon) insulator. In the 50 ohm BNC, the center insulator goes all the way to the tip of the center pin. In the 75 ohm BNC, the center insulator is abbreviated. HP/Agilent uses 75 OHM BNC's on several of its devices that have switchable impedances. For example, the 3586C. -Chuck Harris From dave at uk-ar.co.uk Tue Jun 23 12:40:23 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Tue, 23 Jun 2009 13:40:23 +0100 Subject: [time-nuts] TNC connectors In-Reply-To: Message-ID: > Message: 3 > Date: Tue, 23 Jun 2009 07:54:02 -0400 > From: Chuck Harris > Subject: Re: [time-nuts] TNC connectors > To: Discussion of precise time and frequency measurement > > Message-ID: <4A40C25A.7080403 at erols.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Dave Baxter wrote: > > > Doing that with BNC's will lead to a flaky connection, as > the centre > > pin on the 75r ones is much smaller. The other way round (50r plug > > into 75r > > socket) will damage the socket. As TNC's are very similar > to BNC's ??? > > You are thinking of the incompatibility between 50 ohm and 75 > ohm *N* connectors. > > 75 ohm BNC are use the same center pin hardware as 50 ohm > BNC. The only difference is in the white plastic (teflon) > insulator. In the 50 ohm BNC, the center insulator goes all > the way to the tip of the center pin. In the 75 ohm BNC, the > center insulator is abbreviated. > > HP/Agilent uses 75 OHM BNC's on several of its devices that > have switchable impedances. For example, the 3586C. > > -Chuck Harris Indeed looking as some more data sheets. However, I have somewhere in the deed box at home, some Ex BT BNC's, marked up as 75 Ohm, that have very much smaller center pin's than the common or garden 50r types, as well as less plastic in there too. We once had a Novell computer network in the office, that used 93r coax cable, and 50r BNC's, at 100MBPS. Using Thomas Conrad cards I seem to remember. We still have the real of 93r coax. (It was very much faster end to end, and much more stable than the TCP/IP based Microsoft network we have now, but I digress.) In general, yes indeed size for size, 75r coax will be less lossy than 50r types, but if the RX does present a nominal 50r load, they may be some potential issues. However, if the antenna is an active type, it's probably not worth fussing over. Enough people have used what's recomended I guess and found no problems. Just use good quality cable, not the so called "Low loss" TV coax. I'd guess the foam dielectric "Satelite LNB" cable would do. It fit's 'F' connectors too. Cheers All. Dave B. From david.partridge at dsl.pipex.com Tue Jun 23 13:50:09 2009 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Tue, 23 Jun 2009 14:50:09 +0100 Subject: [time-nuts] TNC connectors In-Reply-To: References: Message-ID: <508DF26D5AAE4ED989C5AD31E7D1736E@APOLLO> Hmmm now all I have to do is find a TNC connector to fit FT100 (or RG6) without paying 5 times thet value of the connector for shipping - or just use RG58 as I've got BNC for this, and can easily get TNC for it too. Thanks to all Dave -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Dave Baxter Sent: 23 June 2009 13:40 To: time-nuts at febo.com Subject: Re: [time-nuts] TNC connectors > Message: 3 > Date: Tue, 23 Jun 2009 07:54:02 -0400 > From: Chuck Harris > Subject: Re: [time-nuts] TNC connectors > To: Discussion of precise time and frequency measurement > > Message-ID: <4A40C25A.7080403 at erols.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Dave Baxter wrote: > > > Doing that with BNC's will lead to a flaky connection, as > the centre > > pin on the 75r ones is much smaller. The other way round (50r plug > > into 75r > > socket) will damage the socket. As TNC's are very similar > to BNC's ??? > > You are thinking of the incompatibility between 50 ohm and 75 ohm *N* > connectors. > > 75 ohm BNC are use the same center pin hardware as 50 ohm BNC. The > only difference is in the white plastic (teflon) insulator. In the 50 > ohm BNC, the center insulator goes all the way to the tip of the > center pin. In the 75 ohm BNC, the center insulator is abbreviated. > > HP/Agilent uses 75 OHM BNC's on several of its devices that have > switchable impedances. For example, the 3586C. > > -Chuck Harris Indeed looking as some more data sheets. However, I have somewhere in the deed box at home, some Ex BT BNC's, marked up as 75 Ohm, that have very much smaller center pin's than the common or garden 50r types, as well as less plastic in there too. We once had a Novell computer network in the office, that used 93r coax cable, and 50r BNC's, at 100MBPS. Using Thomas Conrad cards I seem to remember. We still have the real of 93r coax. (It was very much faster end to end, and much more stable than the TCP/IP based Microsoft network we have now, but I digress.) In general, yes indeed size for size, 75r coax will be less lossy than 50r types, but if the RX does present a nominal 50r load, they may be some potential issues. However, if the antenna is an active type, it's probably not worth fussing over. Enough people have used what's recomended I guess and found no problems. Just use good quality cable, not the so called "Low loss" TV coax. I'd guess the foam dielectric "Satelite LNB" cable would do. It fit's 'F' connectors too. Cheers All. Dave B. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From cfharris at erols.com Tue Jun 23 14:19:24 2009 From: cfharris at erols.com (Chuck Harris) Date: Tue, 23 Jun 2009 10:19:24 -0400 Subject: [time-nuts] TNC connectors In-Reply-To: References: Message-ID: <4A40E46C.70107@erols.com> Dave Baxter wrote: > Indeed looking as some more data sheets. > > However, I have somewhere in the deed box at home, some Ex BT BNC's, > marked up as 75 Ohm, that have very much smaller center pin's than the > common or garden 50r types, as well as less plastic in there too. Connectors that deviate from standards were at one time pretty common. The "Ex BT BNC's" in your junk box are undoubtedly an example. I have run into carbon copies of the old PL259/SO239 UHF connectors that were identical in all respects, including the nomenclature markings, but were metric threaded. And, I have run into alleged BNC's that looked like they were ok, but wouldn't mate with anything I could find. They were a silly millimeter bigger in diameter. > We once had a Novell computer network in the office, that used 93r coax > cable, and 50r BNC's, at 100MBPS. Using Thomas Conrad cards I seem to > remember. We still have the real of 93r coax. 93 ohm coax is standard fare for automobile AM radios in the US. Its claim to fame is its very low capacitance per foot. > (It was very much faster end to end, and much more stable than the > TCP/IP based Microsoft network we have now, but I digress.) > > In general, yes indeed size for size, 75r coax will be less lossy than > 50r types, but if the RX does present a nominal 50r load, they may be > some potential issues. Unlikely. The biggest issue would be edge smearing caused by the received signal bouncing up and down the length of the coax. This effect is minimized because the mismatch is small, and the loss of the coax is pretty high. However, if the antenna is an active type, it's > probably not worth fussing over. Enough people have used what's > recomended I guess and found no problems. Just use good quality cable, > not the so called "Low loss" TV coax. What a thing to say! Quad shielded RG-6 is the minimum quality you will find for today's TV and cable systems. Even RadioShack sells it. It is the same stuff used by the satellite TV guys. I'd guess the foam dielectric > "Satelite LNB" cable would do. It fit's 'F' connectors too. That is because Satellite LNB's use Quad RG 6. Normal TV coax. -Chuck Harris From rdarlington at gmail.com Tue Jun 23 14:34:51 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Tue, 23 Jun 2009 08:34:51 -0600 Subject: [time-nuts] TNC connectors In-Reply-To: <508DF26D5AAE4ED989C5AD31E7D1736E@APOLLO> References: <508DF26D5AAE4ED989C5AD31E7D1736E@APOLLO> Message-ID: I just bought two of these antennas from Bob (fluke.l) and asked him to throw in adapters from TNC on the antenna to female F so I can use ordinary 75 ohm cable TV coax from rat shack. He charged an extra $5 for the adapters which I think is a pretty good deal. Still waiting on delivery so I don't know for sure what was thrown in the box but I'll let you guys know if there was a problem. -Bob On Tue, Jun 23, 2009 at 7:50 AM, David C. Partridge < david.partridge at dsl.pipex.com> wrote: > Hmmm now all I have to do is find a TNC connector to fit FT100 (or RG6) > without paying 5 times thet value of the connector for shipping - or just > use RG58 as I've got BNC for this, and can easily get TNC for it too. > > Thanks to all > Dave > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of Dave Baxter > Sent: 23 June 2009 13:40 > To: time-nuts at febo.com > Subject: Re: [time-nuts] TNC connectors > > > Message: 3 > > Date: Tue, 23 Jun 2009 07:54:02 -0400 > > From: Chuck Harris > > Subject: Re: [time-nuts] TNC connectors > > To: Discussion of precise time and frequency measurement > > > > Message-ID: <4A40C25A.7080403 at erols.com> > > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > > > Dave Baxter wrote: > > > > > Doing that with BNC's will lead to a flaky connection, as > > the centre > > > pin on the 75r ones is much smaller. The other way round (50r plug > > > into 75r > > > socket) will damage the socket. As TNC's are very similar > > to BNC's ??? > > > > You are thinking of the incompatibility between 50 ohm and 75 ohm *N* > > connectors. > > > > 75 ohm BNC are use the same center pin hardware as 50 ohm BNC. The > > only difference is in the white plastic (teflon) insulator. In the 50 > > ohm BNC, the center insulator goes all the way to the tip of the > > center pin. In the 75 ohm BNC, the center insulator is abbreviated. > > > > HP/Agilent uses 75 OHM BNC's on several of its devices that have > > switchable impedances. For example, the 3586C. > > > > -Chuck Harris > > > Indeed looking as some more data sheets. > > However, I have somewhere in the deed box at home, some Ex BT BNC's, marked > up as 75 Ohm, that have very much smaller center pin's than the common or > garden 50r types, as well as less plastic in there too. > > We once had a Novell computer network in the office, that used 93r coax > cable, and 50r BNC's, at 100MBPS. Using Thomas Conrad cards I seem to > remember. We still have the real of 93r coax. > > (It was very much faster end to end, and much more stable than the TCP/IP > based Microsoft network we have now, but I digress.) > > In general, yes indeed size for size, 75r coax will be less lossy than 50r > types, but if the RX does present a nominal 50r load, they may be some > potential issues. However, if the antenna is an active type, it's probably > not worth fussing over. Enough people have used what's recomended I guess > and found no problems. Just use good quality cable, not the so called "Low > loss" TV coax. I'd guess the foam dielectric "Satelite LNB" cable would > do. > It fit's 'F' connectors too. > > Cheers All. > > Dave B. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From jfor at quik.com Tue Jun 23 14:44:01 2009 From: jfor at quik.com (J. Forster) Date: Tue, 23 Jun 2009 07:44:01 -0700 (PDT) Subject: [time-nuts] TNC connectors In-Reply-To: <97A430416D9546F0BED1FCE6D3656699@APOLLO> References: <97A430416D9546F0BED1FCE6D3656699@APOLLO> Message-ID: <1088.12.6.201.127.1245768241.squirrel@popacctsnew.quik.com> [snip] On my FTS antenna it's just a standard 1" NPT male thread (NPT = National Pipe Thread). Any US plumbing supply store or home improvement store will sell you iron pipe threaded that way or adapters to go to PVC or copper. -John ============ > PS Where do you get the (1" diameter?) threaded poles these antennas screw > onto? > > Cheers > David Partridge From cfharris at erols.com Tue Jun 23 14:56:28 2009 From: cfharris at erols.com (Chuck Harris) Date: Tue, 23 Jun 2009 10:56:28 -0400 Subject: [time-nuts] TNC connectors In-Reply-To: <1088.12.6.201.127.1245768241.squirrel@popacctsnew.quik.com> References: <97A430416D9546F0BED1FCE6D3656699@APOLLO> <1088.12.6.201.127.1245768241.squirrel@popacctsnew.quik.com> Message-ID: <4A40ED1C.8030605@erols.com> If the thread measures 1 inch, it isn't 1 inch pipe thread. It is more likely 1/2 inch pipe thread, or possibly 3/4 inch, depending on how accurately you measured. 1 inch pipe is 1-3/8 inch OD, 3/4 inch pipe is 1-1/16 inch OD, and 3/4 inch pipe is 7/8 inch OD. -Chuck Harris J. Forster wrote: > [snip] > > On my FTS antenna it's just a standard 1" NPT male thread (NPT = National > Pipe Thread). Any US plumbing supply store or home improvement store will > sell you iron pipe threaded that way or adapters to go to PVC or copper. > > -John > > ============ > > >> PS Where do you get the (1" diameter?) threaded poles these antennas screw >> onto? >> >> Cheers >> David Partridge From jfor at quik.com Tue Jun 23 15:00:22 2009 From: jfor at quik.com (J. Forster) Date: Tue, 23 Jun 2009 08:00:22 -0700 (PDT) Subject: [time-nuts] TNC connectors In-Reply-To: <4A40ED1C.8030605@erols.com> References: <97A430416D9546F0BED1FCE6D3656699@APOLLO> <1088.12.6.201.127.1245768241.squirrel@popacctsnew.quik.com> <4A40ED1C.8030605@erols.com> Message-ID: <1140.12.6.201.127.1245769222.squirrel@popacctsnew.quik.com> I just took the antenna to Home Depot and looked through the bins, found something that fit well, paid, and left. LoL. Whatever the nominal Pipe size, mine is NPT for sure. -John ========== > If the thread measures 1 inch, it isn't 1 inch pipe thread. It is > more likely 1/2 inch pipe thread, or possibly 3/4 inch, depending on > how accurately you measured. 1 inch pipe is 1-3/8 inch OD, 3/4 inch > pipe is 1-1/16 inch OD, and 3/4 inch pipe is 7/8 inch OD. > > -Chuck Harris > > J. Forster wrote: >> [snip] >> >> On my FTS antenna it's just a standard 1" NPT male thread (NPT = >> National >> Pipe Thread). Any US plumbing supply store or home improvement store >> will >> sell you iron pipe threaded that way or adapters to go to PVC or copper. >> >> -John >> >> ============ >> >> >>> PS Where do you get the (1" diameter?) threaded poles these antennas >>> screw >>> onto? >>> >>> Cheers >>> David Partridge > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From stanw1le at verizon.net Tue Jun 23 15:01:40 2009 From: stanw1le at verizon.net (Stan W1LE) Date: Tue, 23 Jun 2009 11:01:40 -0400 Subject: [time-nuts] TNC connectors In-Reply-To: <97A430416D9546F0BED1FCE6D3656699@APOLLO> References: <97A430416D9546F0BED1FCE6D3656699@APOLLO> Message-ID: <4A40EE54.7000502@verizon.net> Hello Dave, I looked for that antenna but could not find it, to understand how to mate to it. Consider using to a coaxial adapter at the antenna, TNC male to BNC female. Then put a BNC male connector on whatever coax you will be using. In an ideal world, a 75 ohm TNC will NOT mate a 50 ohm TNC. May feel like it is screwed in properly but the diameter of the center pin is smaller for the 75 ohm version. So, if you jam in a larger 50 ohm male center pin into a smaller 75 ohm female center pin, you will destroy it. Having said that, most connectors you find will be 50 ohm, just be watchful for the odd ball. I got my chromed pipe for the GPS antenna from a friend. Actual O.D. is 1.007" and the male thread looks to be a straight thread. Check the specs on the Panasonic antenna for the mating thread required. Check out the Home Depot's plumbing section for either galvi pipe or white PVC pipe. The electrical section will have a grey PVC pipe that may be more suitable and UV proof. Stan, W1LE Cape Cod FN41sr David C. Partridge wrote: > I'm thinking of buying a Panasonic VIC100 timing antenna with a 50 ohm TNC > connector (I assume) from fluke.l on eBay, as the room I use for my den has > moved to one without a view to the south, so I can't use the puck antenna > mounted just outside the window any more. > > The T-Bolt manual recommends 75 ohm coax, so will a 75 ohm TNC mate with a > 50 ohm TNC without problems? Though I suppose for a short run of cable, 50 > ohm will be OK? > > PS Where do you get the (1" diameter?) threaded poles these antennas screw > onto? > > Cheers > David Partridge > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From dave at uk-ar.co.uk Tue Jun 23 16:49:37 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Tue, 23 Jun 2009 17:49:37 +0100 Subject: [time-nuts] OT: Re: TNC connectors In-Reply-To: Message-ID: Chuck, please realise we're in the UK, not the US, so things are significantly different in many ways... "TV coax" hear is really cheap cruddy stuff, if you're very lucky you might get 50% braid/shielding coverage! There was no real need to prevent ingress or egress of signals, as (other than channel 36 around some airports) that band was dedicated to broadcast TV. Unlike in the US, where your cable distribution systems had to be buttoned up quite well, as the same frequencies are also used over the air for "other services" etc. The "Satellite LNB" coax that you regard as "standard TV coax", has only recently become common over here, since the rise in popularity of Satellite TV, and the need to use good quality cable, as well as keeping stuff in or out as needed. Yes, I'm aware of the old "AM" car radio aerial cable. But from what I've seen (still got in places) that was a very poor imitation of the 93r coax we used for the network. Almost no braid, and the very thin "wire" (much thinner than in the network cable) just floating about in the tube dielectric, no spiral filament to hold it in the centre. But it was no doubt cheap to produce. (That reminds me, I need a replacement broadcast antenna for the 4x4, the last one argued with a tree, and lost, not as rugged as advertised!) Metric vs Imperial: Wasn't the USA supposed to go Metric decades ago? Many instrument makers managed it (IBM, HP, TEK etc.) But the folklore I remember when I was in the US just down 101 from San Jose back in the early 90's, states that most small (jobbing) metal bashing suppliers just plain refused to push the "Metric" button on their CNC machines ;-) Certainly, the ones we used would and could do metric if you really wanted, but they didn't half grumble about it... (They did a good job though!) Non standard connectors, yes, it happens. BT in this context is British Telecom, and I guess they could have had connectors made especially for them. But I've also seen the same things on Ex BBC broadcast and other kit. Closely allied to BT or the GPO as it used to be it has to be said, so no surprise there I guess. In either case, I suspect it effectively became a "Standard" over hear within that industry. "Metric UHF connector threads". Yep, whatever the thread is supposed to be, there are many variations on that theme (and also the exact size of the centre pin!) Another reason I avoid them like the plague!. Not least their tendency to explode in flames with a kilowatt flowing through them! There again, I've also destroyed good clean N connectors with less RF than that. (Bad VSWR problems!) "Radio Shack" never existed in the UK. There was a brief period where "Tandy" was on the high street, with Rat Shack branded products. "RS" over hear stands for what used to be "Radio Spares". Now RS Components, one of the big (huge) catalogue based component suppliers, like your Mouser or DigiKey (who are also over hear in a small but expensive way.) Even then, Tandy went for the "Gadget" toy and phone market, abandoning even the small line of components they had, their products were of doubtful quality as well from what I remember. The closest now in the UK would be Maplin, though they are slowly moving away from components, towards toys, gadgets, PC's and phones etc. Go in to there and start asking for TNC connectors, and you'll probably get a blank stare... What you call RCA connectors, we call "Phono" connectors. Another example. Interestingly, Maplin do this... http://www.maplin.co.uk/Module.aspx?ModuleNo=1587&C=SO&U=strat15 A TNC Male, to BNC Female adapter. For the impressive cost of ?1.89 Useful to know. Now all you have to do, is find a store with one in stock, and what the "Quality" is like is anyone's guess at that price. Pipe threads and mounting poles... We can't just go to "Any US plumbing supply store". There are DIY equivalent stores here of course, but you'd be very lucky indeed to find any iron water piping for domestic use these days. Threaded or otherwise! Even our water plumbing (Hot as well as cold) is moving towards plastic and push fit fittings. (!) Again, please be aware we are not in the USA, and 90+% of all our suppliers are exclusively metric, so it can be an issue to get the "correct stuff", when it is critical, and it is some odd (to us) imperial size or thread fitting.. Strangely, the more common it is in the US, the scarcer it is over hear it seems. Bit like trying to by Tea bags and Branston Pickle in the US. Not to say a decent electric kettle! :-) 'Nuff said I think. Regards to all. Dave B. From jfor at quik.com Tue Jun 23 17:11:22 2009 From: jfor at quik.com (J. Forster) Date: Tue, 23 Jun 2009 10:11:22 -0700 (PDT) Subject: [time-nuts] OT: Re: TNC connectors In-Reply-To: References: Message-ID: <1358.12.6.201.173.1245777082.squirrel@popacctsnew.quik.com> > Chuck, please realise we're in the UK [snip] > Metric vs Imperial: Wasn't the USA supposed to go Metric decades ago? > Many instrument makers managed it (IBM, HP, TEK etc.) But the folklore I > remember when I was in the US just down 101 from San Jose back in the > early 90's, states that most small (jobbing) metal bashing suppliers just > plain refused to push the "Metric" button on their CNC machines ;-) > Certainly, the ones we used would and could do metric if you really > wanted, but they didn't half grumble about it... (They did a good job > though!) Yes, but it really didn't happen. HP and maybe Tek did switch for the world market as did the car makers, but metric fastners are still a minority here. Most 'home centers' do carry some sizes in small quantities at high prices. [snip] > "Radio Shack" never existed in the UK. There was a brief period where > "Tandy" was on the high street, with Rat Shack branded products. "RS" > over hear stands for what used to be "Radio Spares". Now RS Components, > one of the big (huge) catalogue based component suppliers, like your > Mouser or DigiKey (who are also over hear in a small but expensive way.) Their motto is "You got questions, we got cell phones". Actually, they do have a minimal selection of parts (about the only people in most areaws that do) but it's really cell phones, toys, and consumer electronics like TVs. > Even then, Tandy went for the "Gadget" toy and phone market, abandoning > even the small line of components they had, their products were of > doubtful quality as well from what I remember. The closest now in the UK > would be Maplin, though they are slowly moving away from components, > towards toys, gadgets, PC's and phones etc. Go in to there and start > asking for TNC connectors, and you'll probably get a blank stare... > > What you call RCA connectors, we call "Phono" connectors. Another > example. Both names are used in the US. > Interestingly, Maplin do this... > http://www.maplin.co.uk/Module.aspx?ModuleNo=1587&C=SO&U=strat15 > > A TNC Male, to BNC Female adapter. For the impressive cost of ?1.89 > Useful to know. Now all you have to do, is find a store with one in > stock, and what the "Quality" is like is anyone's guess at that price. > > Pipe threads and mounting poles... We can't just go to "Any US plumbing > supply store". There are DIY equivalent stores here of course, but you'd > be very lucky indeed to find any iron water piping for domestic use these > days. Threaded or otherwise! Even our water plumbing (Hot as well as > cold) is moving towards plastic and push fit fittings. (!) Iron pipe comes in two types: Black and galvanized. The former is for gas, the later for water (and is rarely used, except for old work these days). The water systems in the UK used to be very different than here, with supply pressures from 30 to 120 PSI. There have also been some massive problems with plastic pipe fittings leaking. Copper w/ soldered connections has been the best choice although that may be cfhanging. Plastic, because it's flexible, is cheaper to install. > Again, please be aware we are not in the USA, and 90+% of all our > suppliers are exclusively metric, so it can be an issue to get the > "correct stuff", when it is critical, and it is some odd (to us) imperial > size or thread fitting.. I don't know if there is a Metric standard corresponding to NPT, but 've seen fittings (like Swageloc) for Metric tubing with NPT threads. > > Strangely, the more common it is in the US, the scarcer it is over hear it > seems. Bit like trying to by Tea bags and Branston Pickle in the US. Not > to say a decent electric kettle! :-) The first and third are common. -John > > 'Nuff said I think. > > Regards to all. > > Dave B. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From holrum at hotmail.com Tue Jun 23 18:08:20 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 23 Jun 2009 18:08:20 +0000 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: Lady Heather is undergoing her periodic trip to the beauty parlor. A few new gratuitous features have already crept in: * You can specify a time/date for the program to exit * The satellite elevation shows if the satellite is rising or setting * You can show the times in your local time zone * Periods of holdover are flagged in the plot * The tbolt version and serial info is written to the log file * You can specify command line options in a .CFG file Now would be a good time to suggest any new features that you can't live without... _________________________________________________________________ Microsoft brings you a new way to search the web. Try Bing? now http://www.bing.com?form=MFEHPG&publ=WLHMTAG&crea=TEXT_MFEHPG_Core_tagline_try_bing_1x1 From robert8rpi at yahoo.co.uk Tue Jun 23 18:31:13 2009 From: robert8rpi at yahoo.co.uk (Robert Atkinson) Date: Tue, 23 Jun 2009 18:31:13 +0000 (GMT) Subject: [time-nuts] OT: Re: 1" poles in UK Message-ID: <241209.67814.qm@web27105.mail.ukl.yahoo.com> The 1" mounts used for many GPS antennas are available in the UK. They are common on boats and available from most ships chandler's (price is another thing). I have a Shakespear adjustable mount and fibreglass extension. Then there is always *bay. Robert G8RPI. --- On Tue, 23/6/09, Dave Baxter wrote: > From: Dave Baxter > Subject: [time-nuts] OT: Re: TNC connectors > To: time-nuts at febo.com > Date: Tuesday, 23 June, 2009, 5:49 PM > Chuck, please realise we're in the > UK, not the US, so things are significantly different in > many ways... > > "TV coax" hear is really cheap cruddy stuff, if you're very > lucky you might get 50% braid/shielding > coverage!???There was no real need to prevent > ingress or egress of signals, as (other than channel 36 > around some airports) that band was dedicated to broadcast > TV. > > Unlike in the US, where your cable distribution systems had > to be buttoned up quite well, as the same frequencies are > also used over the air for "other services" etc.? > > The "Satellite LNB" coax that you regard as "standard TV > coax", has only recently become common over here, since the > rise in popularity of Satellite TV, and the need to use good > quality cable, as well as keeping stuff in or out as > needed. > > Yes, I'm aware of the old "AM" car radio aerial > cable.? But from what I've seen (still got in places) > that was a very poor imitation of the 93r coax we used for > the network.? Almost no braid, and the very thin "wire" > (much thinner than in the network cable) just floating about > in the tube dielectric, no spiral filament to hold it in the > centre.? But it was no doubt cheap to produce.? > (That reminds me, I need a replacement broadcast antenna for > the 4x4, the last one argued with a tree, and lost, not as > rugged as advertised!) > > Metric vs Imperial:???Wasn't the USA > supposed to go Metric decades ago?? Many instrument > makers managed it (IBM, HP, TEK etc.)? But the folklore > I remember when I was in the US just down 101 from San Jose > back in the early 90's, states that most small (jobbing) > metal bashing suppliers just plain refused to push the > "Metric" button on their CNC machines? ;-)? ? > Certainly, the ones we used would and could do metric if you > really wanted, but they didn't half grumble about > it...? (They did a good job though!) > > Non standard connectors, yes, it happens.? BT in this > context is British Telecom, and I guess they could have had > connectors made especially for them.? But I've also > seen the same things on Ex BBC broadcast and other > kit.???Closely allied to BT or the GPO as it > used to be it has to be said, so no surprise there I > guess.? In either case, I suspect it effectively became > a "Standard" over hear within that industry. > > "Metric UHF connector threads".? Yep, whatever the > thread is supposed to be, there are many variations on that > theme (and also the exact size of the centre pin!)? > Another reason I avoid them like the plague!.? Not > least their tendency to explode in flames with a kilowatt > flowing through them!? There again, I've also destroyed > good clean N connectors with less RF than that.? (Bad > VSWR problems!) > > "Radio Shack" never existed in the UK.? There was a > brief period where "Tandy" was on the high street, with Rat > Shack branded products.? "RS" over hear stands for what > used to be "Radio Spares".? Now RS Components, one of > the big (huge) catalogue based component suppliers, like > your Mouser or DigiKey (who are also over hear in a small > but expensive way.) > > Even then, Tandy went for the "Gadget" toy and phone > market, abandoning even the small line of components they > had, their products were of doubtful quality as well from > what I remember.???The closest now in the UK > would be Maplin, though they are slowly moving away from > components, towards toys, gadgets, PC's and phones > etc.? Go in to there and start asking for TNC > connectors, and you'll probably get a blank stare... > > What you call RCA connectors, we call "Phono" > connectors.? Another example. > > Interestingly, Maplin do this... > http://www.maplin.co.uk/Module.aspx?ModuleNo=1587&C=SO&U=strat15 > > A TNC Male, to BNC Female adapter.? For the impressive > cost of ?1.89? Useful to know.???Now > all you have to do, is find a store with one in stock, and > what the "Quality" is like is anyone's guess at that price. > > Pipe threads and mounting poles...???We > can't just go to "Any US plumbing supply store".? There > are DIY equivalent stores here of course, but you'd be very > lucky indeed to find any iron water piping for domestic use > these days.? Threaded or otherwise!? Even our > water plumbing (Hot as well as cold) is moving towards > plastic and push fit fittings.? (!) > > Again, please be aware we are not in the USA, and 90+% of > all our suppliers are exclusively metric, so it can be an > issue to get the "correct stuff", when it is critical, and > it is some odd (to us) imperial size or thread fitting.. > > Strangely, the more common it is in the US, the scarcer it > is over hear it seems.? Bit like trying to by Tea bags > and Branston Pickle in the US.? Not to say a decent > electric kettle!? :-) > > 'Nuff said I think. > > Regards to all. > > Dave B. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From brooke at pacific.net Tue Jun 23 18:39:54 2009 From: brooke at pacific.net (Brooke Clarke) Date: Tue, 23 Jun 2009 11:39:54 -0700 Subject: [time-nuts] Lady Heather Request Sig Str vs 0- 24 Sidereal hrs Message-ID: <4A41217A.20707@pacific.net> Hi Mark: I've been told that by plotting the signal strength for each satellite you can see multipath distortion as oscillations near rise and set. Is there a way to see a plot of SV signal strength for all 32 satellites? Since each GPS satellite has the same ground track they would overlay each other if the signal strength plot used siderial time instead of UTC. Is there a way to plot the signal strength for each SV vs. sidereal time 0 to 24 hours? -- Have Fun, Brooke Clarke http://www.prc68.com From magnus at rubidium.dyndns.org Tue Jun 23 18:42:32 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 23 Jun 2009 20:42:32 +0200 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: <4A412218.8090708@rubidium.dyndns.org> Mark Sims skrev: > Lady Heather is undergoing her periodic trip to the beauty parlor. A few new gratuitous features have already crept in: > * You can specify a time/date for the program to exit > * The satellite elevation shows if the satellite is rising or setting > * You can show the times in your local time zone > * Periods of holdover are flagged in the plot > * The tbolt version and serial info is written to the log file > * You can specify command line options in a .CFG file > > Now would be a good time to suggest any new features that you can't live without... Last time I was down in Lady Heathers dungeon she didn't have any PLL control options and other related time configuration parameters... Cheers, Magnus From Arnold.Tibus at gmx.de Tue Jun 23 19:09:49 2009 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Tue, 23 Jun 2009 21:09:49 +0200 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: Message-ID: On Tue, 23 Jun 2009 18:08:20 +0000, Mark Sims wrote: >Lady Heather is undergoing her periodic trip to the beauty parlor. A few new gratuitous features have already crept in: >* You can specify a time/date for the program to exit >* The satellite elevation shows if the satellite is rising or setting >* You can show the times in your local time zone >* Periods of holdover are flagged in the plot >* The tbolt version and serial info is written to the log file >* You can specify command line options in a .CFG file >Now would be a good time to suggest any new features that you can't live without... Hello Mark, normally I do run LH without the log option tick. but in some cases it would be fine for me to have still the option to save (or discard) the data when stopping the program. I think the data are still in the memory because I can walk back in the graphics part... Is there a way to put in that feature? Many thanks so far for this very practical and useful tool! regards Arnold From xde-l2g3 at myamail.com Tue Jun 23 18:16:53 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Tue, 23 Jun 2009 15:16:53 -0300 Subject: [time-nuts] LF power supply noise Message-ID: Magnus wrote: Mike wrote: >>> So about the only thing left of interest is histograms of the >>> jitter. Unfortunately, the 543310A cannot store enough samples to >>> really make an interesting graph. What I would like to be able to >>> do is similar to an invention I made for the disk industry long >>> ago, called Phase Margin Analysis. There is a brief description >>> on my web page at >>> http://pstca.com/patents.htm#phasemargin >> Somewhere in my map of apps there is a HP appnote for doing the >> same, to discs, intended for disc industry, back in the days. > That may very well be a result of my invention, which occurred in > 1970, was published in 1979, and was copied by IBM in the 1990's. > But I have all the HP appnotes for disk. I don't recall any of > them describing what I show above. Can you provide more > information? I found it. AN 191-7, 8.34 MB PDF, for the 5370B Universal Time Interval Counter Dated 1987-06-01 url: http://cp.literature.agilent.com/litweb/pdf/5952-7908.pdf web page: There are so many thing wrong with that app note I don't have time to list them all. First, it is dated June, 1987. That is 17 years after I invented Phase Margin Analysis, and 8 years after the Katz & Campbell article was published in IEEE Transactions on Magnetics. By this time, the technique of Phase Margin Analysis was used in every hard disk company all over the world. You simply could not design, analyze, or manufacture a hard disk without it. So it was well known and understood. But in this case, it looks like some junior applications engineer got a brilliant idea to advance his career and publish this app note. He has no clue about magnetic recording and what it takes to store data on the disk and read it back. The article was written for floppy disks. The maximum rate of data collection is mentioned at 8,000 samples/sec. That is useless. In order to detect the loss in margin caused by a single bit defect, you must collect data on each and every transition. For example, see Figs 6 and 7 in the Katz paper: http://pstca.com/pdfs/katz.pdf Thus, 8,000 samples/sec is far below the data rate needed for floppy, and hopelessly inadequate for hard disk. The timing measurement described in the app note does not clearly describe where the data and clock signals come from. Ideally, the timing measurement should be made at the output of the PFD in order to include any offsets in the phase detector, and to include the loop dynamics in the measurement. For example, the heads on a hard disk flutter as they move across bumps and imperfections in the surface. This causes a phase error in the loop that can turn a minor disk defect into a hard error, or mask an error by shifting the phase in the opposite direction. A similar effect occurs on floppy disk with imperfections and variations in the coating thickness. The next time the sector is written, the timing shifts slightly. So what was previously an error-free disk suddenly turns into a hard error. Or vice-versa. For example, see my micro-defect patent at These issues are not emphasized in the app note, so it is unlikely the author is even aware of them. It is not clear how the 5370B is connected to the electronics. Just blindly hooking up cables could cause all sorts of loading and grounding problems. These issues are not emphasized in the app note, so it is unlikely the author is even aware of them. The Gaussian curve is a parabola when measured on log-linear plot. Any deviation from a parabolic curve on the side of the margin plot is an indication of problems that need to be addressed. The plots in the Katz paper all show the parabolic drop. But the plots in the app note have any kind of shape you may want, and the software allows you to select various parameters for the curve fit. This is wrong. The plots shown in the app note are useless for making analytical measurements of the performance of the channel. The app note is wrong, misleading, propagates false information about data channels and measuring Phase Margin, and should never have been published. I could go on, and will probably kick myself for forgetting some hugely important issue. But I have to stop and work on several other issues that suddenly came up. (Nothing terribly important. My landlord needs some help with urgent problems in the laundromat and kitchen. He is a nice guy so I try to help whenever I can, and he counts on me when problems crop up. So one minute I am analyzing one of the most exotic measurement capabilities available on the planet, and the next minute I am buried in a front load washer trying to figure why the drain valve is stuck open, then fixing a broken tomato slicing machine:) Regards, Mike From cfharris at erols.com Tue Jun 23 19:41:57 2009 From: cfharris at erols.com (Chuck Harris) Date: Tue, 23 Jun 2009 15:41:57 -0400 Subject: [time-nuts] TNC connectors In-Reply-To: <1140.12.6.201.127.1245769222.squirrel@popacctsnew.quik.com> References: <97A430416D9546F0BED1FCE6D3656699@APOLLO> <1088.12.6.201.127.1245768241.squirrel@popacctsnew.quik.com> <4A40ED1C.8030605@erols.com> <1140.12.6.201.127.1245769222.squirrel@popacctsnew.quik.com> Message-ID: <4A413005.8070606@erols.com> Hi John, I only mentioned it so that someone wouldn't measure 1 inch, and walk off to Home Depot and ask for 1 inch, only to be in for a big surprise. -Chuck Harris J. Forster wrote: > I just took the antenna to Home Depot and looked through the bins, found > something that fit well, paid, and left. LoL. Whatever the nominal Pipe > size, mine is NPT for sure. > > -John > > ========== > >> If the thread measures 1 inch, it isn't 1 inch pipe thread. It is >> more likely 1/2 inch pipe thread, or possibly 3/4 inch, depending on >> how accurately you measured. 1 inch pipe is 1-3/8 inch OD, 3/4 inch >> pipe is 1-1/16 inch OD, and 3/4 inch pipe is 7/8 inch OD. >> >> -Chuck Harris From jfor at quik.com Tue Jun 23 19:55:48 2009 From: jfor at quik.com (J. Forster) Date: Tue, 23 Jun 2009 12:55:48 -0700 (PDT) Subject: [time-nuts] TNC connectors In-Reply-To: <4A413005.8070606@erols.com> References: <97A430416D9546F0BED1FCE6D3656699@APOLLO> <1088.12.6.201.127.1245768241.squirrel@popacctsnew.quik.com> <4A40ED1C.8030605@erols.com> <1140.12.6.201.127.1245769222.squirrel@popacctsnew.quik.com> <4A413005.8070606@erols.com> Message-ID: <1612.12.6.201.150.1245786948.squirrel@popacctsnew.quik.com> True. I always take the to be mated part w/ me to avoid repeat trips. -John ========= > Hi John, > > I only mentioned it so that someone wouldn't measure 1 inch, and > walk off to Home Depot and ask for 1 inch, only to be in for a big > surprise. > > -Chuck Harris > > J. Forster wrote: >> I just took the antenna to Home Depot and looked through the bins, found >> something that fit well, paid, and left. LoL. Whatever the nominal Pipe >> size, mine is NPT for sure. >> >> -John >> >> ========== >> >>> If the thread measures 1 inch, it isn't 1 inch pipe thread. It is >>> more likely 1/2 inch pipe thread, or possibly 3/4 inch, depending on >>> how accurately you measured. 1 inch pipe is 1-3/8 inch OD, 3/4 inch >>> pipe is 1-1/16 inch OD, and 3/4 inch pipe is 7/8 inch OD. >>> >>> -Chuck Harris > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From holrum at hotmail.com Tue Jun 23 20:02:07 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 23 Jun 2009 20:02:07 +0000 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: Hello Arnold, That feature is already in the current release (v 2.0). You can use the 'w' keyboard command to write the data to a file. You can select either the complete buffer or just the time span displayed on the screen. --------------------------- normally I do run LH without the log option tick. but in some cases it would be fine for me to have still the option to save (or discard) the data when stopping the program. _________________________________________________________________ Hotmail? has ever-growing storage! Don?t worry about storage limits. http://windowslive.com/Tutorial/Hotmail/Storage?ocid=TXT_TAGLM_WL_HM_Tutorial_Storage_062009 From holrum at hotmail.com Tue Jun 23 20:02:52 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 23 Jun 2009 20:02:52 +0000 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: Hello Arnold, That feature is already in the current release (v 2.0). You can use the 'w' keyboard command to write the data to a file. You can select either the complete buffer or just the time span displayed on the screen. --------------------------- normally I do run LH without the log option tick. but in some cases it would be fine for me to have still the option to save (or discard) the data when stopping the program. _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From holrum at hotmail.com Tue Jun 23 20:05:51 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 23 Jun 2009 20:05:51 +0000 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: Hello Magnus, The current version (v 2.0) already supports modifying the pll and oscillator parameters. Use the '&' keyboard command. _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From stanw1le at verizon.net Tue Jun 23 20:07:06 2009 From: stanw1le at verizon.net (Stan W1LE) Date: Tue, 23 Jun 2009 16:07:06 -0400 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: <4A4135EA.2080506@verizon.net> Hello Mark, I appreciate LH and your development effort. I do not log data, but rather I periodically do a screen grab as a graphics file. From this saved single screen I would like to know the program info, version and date. Granted this data is on a second help screen, but I would prefer it to be on the main screen along with tabular data and plotted data. Thanks Stan, W1LE Cape Cod FN41sr Mark Sims wrote: > Lady Heather is undergoing her periodic trip to the beauty parlor. A few new gratuitous features have already crept in: > * You can specify a time/date for the program to exit > * The satellite elevation shows if the satellite is rising or setting > * You can show the times in your local time zone > * Periods of holdover are flagged in the plot > * The tbolt version and serial info is written to the log file > * You can specify command line options in a .CFG file > > Now would be a good time to suggest any new features that you can't live without... > _________________________________________________________________ > Microsoft brings you a new way to search the web. Try Bing? now > http://www.bing.com?form=MFEHPG&publ=WLHMTAG&crea=TEXT_MFEHPG_Core_tagline_try_bing_1x1 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From xde-l2g3 at myamail.com Tue Jun 23 21:31:27 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Tue, 23 Jun 2009 18:31:27 -0300 Subject: [time-nuts] LF power supply noise Message-ID: Magnus wrote: > I has issues with the big permanent magnet of one of my speakers > made one of my screens going all strange in colours. I had some > backsides from a pair of racks which I put inbetween, and the > steel was doing a good job as finding a better path for the > magnetic fields than through my screen. > Maybe you should put a few slabs of steel around that HP543310A to > at least guide most of the magnetic fields back into the core. > Cheers, > Magnus I was wondering where that funny HP number came from. The HP543310A was from your post above, and I just copied and pasted it everywhere as needed. Then you blamed me for the mistake! Way to go Magnus. I'll check things a bit more carefully now. Regards, Mike From Leigh at WA5ZNU.org Tue Jun 23 23:34:10 2009 From: Leigh at WA5ZNU.org (Leigh L. Klotz, Jr. WA5ZNU) Date: Tue, 23 Jun 2009 16:34:10 -0700 (PDT) Subject: [time-nuts] Ideas for a long-wave receiver sought In-Reply-To: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> References: <38553AAD-ECC6-4AF8-90B3-42BBEC366CA6@msys.ch> Message-ID: <7dbd665a6325b472c1d8163e49651d10.squirrel@graflex.org> Are you doing DGPS? An an alterative to the roll-your-own SDR, tou can build a direct conversion small receiver or IF converter with a SA602 chip, which contains a Gilbert cell mixer and a local oscillator. Here is a board that will do most of what you want, if you're willing to live with the SA602 limitation. http://home.att.net/~jacksonharbor/lfconv.htm You will get out of this board LO + (0 to 500 Khz), which you can the receive with an existing receiver that can receive the LO frequency. It comes with 4.0 and 10.0 MHz crystals. Here's an article about better input filtering against AM broadcast band interference, which will be useful for you no matter what route you take for LF and VLF reception. http://www.cliftonlaboratories.com/jackson_harbor_press_vlf_converter.htm There are many ham and non-hams who are using very low bit-rate signals in LF and VLF at micro power levels. As a result, they care about frequency stability, and some are building their own RX equipment. Here's a random sample: http://www.qrss.thersgb.net/Receiving-QRSS.html . Murray Greenman who is a member of this group did some pioneering work in VLF TX using the FE5680A as a transmitter, and he may have something to contribute on RX as well. If you need better phase noise and frequency stability, you won't get that from a product like the SA602, not the least because of its internal oscillator. You can build a receiver or IF converter yourself out of discrete mixers from Mini-Circuits, but you'll likely need a preamp as well as they generally require higher drive points (more loss), and output filters as well to deal with the image rejection. Leigh. > Hi > > I want to build a small, cheap, yet precise long-wave receiver which > can be > tuned from the computer in the 2KHz - 200 KHz range (the intended use > is to receive various time signal stations). > > Does a chip for such a receiver exist? Should I take the SDR route? > I designed a DCF77 receivers some years ago, but I need something > more flexible (and a bit more modern...) > > - Marc Balmer > From SAIDJACK at aol.com Wed Jun 24 04:17:23 2009 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Wed, 24 Jun 2009 00:17:23 EDT Subject: [time-nuts] Introduction of Z38XX Message-ID: Hi Ulrich, since our FireFly and Fury GPSDO's support GPSCon as well, I tried your plot program. We use 115.200 baud by default, but when I set your program to that speed, it defaults back to 57600 for some reason. Changing our board's baud rate fixed that problem. Our status output is shown properly in your status window (see below), and the *IDN? string is shown as well, but the program says "the last smartclock status is undefined". What commands do you use to query the GPSDO that it may be getting hung up on? Your software looks quite nice, and It would be great if your software could support our units like GPSCon does. Thanks in advance, Said The status window in your software shows the following: :SYSTEM:STATUS? AQUISITION ................................................ Tracking:10 Not Tracking: 3 PRN El Az SS PRN El Az 2 42 175 24 14 0 331 4 59 119 21 28 17 101 9 59 283 33 51 44 156 12 27 303 25 15 6 218 11 17 36 49 29 20 1 47 19 26 18 267 29 27 65 250 33 48 45 197 39 UTC 4:12:45 24 Jun 2009 LAT N 37:16:17.915 LON W 121:57:26.719 HGT 71.20 m (MSL) HEALTH MONITOR................................................ OCXO Current: OK EFC: OK GPS Receiver Status: 3D Fix 1PPS SOURCE MODE : GPS 1PPS SOURCE STATE : GPS GPSDO Status : Locked In a message dated 6/23/2009 02:29:05 Pacific Daylight Time, df6jb at ulrich-bangert.de writes: Z38XX talks to the Z3801/5/16 with a exact 10 s time base which means the PPS TI delivered can be used for the computation of Allan deviation (and other measures) of the internal phase comparator with a Tau0 = 10 s (which is done internally in Z38XX similar as in Lady Heather). The sat's horizont line in the Azimuth / Elevation chart will look strange in the first hours after program start. Give it some days until it looks as attched or even better. Have fun Ulrich Bangert From magnus at rubidium.dyndns.org Wed Jun 24 08:43:42 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 24 Jun 2009 10:43:42 +0200 Subject: [time-nuts] LF power supply noise In-Reply-To: References: Message-ID: <4A41E73E.8040509@rubidium.dyndns.org> Mike Monett skrev: > Magnus wrote: > > > I has issues with the big permanent magnet of one of my speakers > > made one of my screens going all strange in colours. I had some > > backsides from a pair of racks which I put inbetween, and the > > steel was doing a good job as finding a better path for the > > magnetic fields than through my screen. > > > Maybe you should put a few slabs of steel around that HP543310A to > > at least guide most of the magnetic fields back into the core. > > > Cheers, > > Magnus > > I was wondering where that funny HP number came from. The HP543310A > was from your post above, and I just copied and pasted it > everywhere as needed. > > Then you blamed me for the mistake! > > Way to go Magnus. I'll check things a bit more carefully now. Not blame, you are making a chicken out of the feather... a mistyping can occur, I was just wondering why you where so consistent about it. BTW, as for the HP appnote, you got the wrong one. I was refering to one written for HP 5371A and/or HP5372A and not the HP 5370A/B. I think it is in the App note 358 series. Regardless, I have not spent quality time over it as it does not address issues which is particular useful for me as I don't do disc drives and rarely to those low rates of bitstreams. Cheers, Magnus From xde-l2g3 at myamail.com Wed Jun 24 12:50:38 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Wed, 24 Jun 2009 09:50:38 -0300 Subject: [time-nuts] LF power supply noise References: Message-ID: > Mike Monett skrev: >> Way to go Magnus. I'll check things a bit more carefully now. > Not blame, you are making a chicken out of the feather... a > mistyping can occur, I was just wondering why you where so > consistent about it. Copy & paste. Saves time and usually eliminates typos. But I should have checked more carefully, and will do so in the future. > BTW, as for the HP appnote, you got the wrong one. I was refering > to one written for HP 5371A and/or HP5372A and not the HP 5370A/B. > I think it is in the App note 358 series. Regardless, I have not > spent quality time over it as it does not address issues which is > particular useful for me as I don't do disc drives and rarely to > those low rates of bitstreams. > Cheers, > Magnus The HP museum shows the following list for the 358 series (sorry for the wrap) 358-1 1987 5371A Characterization of Frequency-Agile Signal Sources 358-2 1987 5371A Jitter and Wander Analysis in Digital Communications 358-3 1988 5371A Time Domain Characterization of Magnetic Disk Drives 358-4 1989 5372A Pre-Trigger Simplifies VCO Step Response Measurements 358-5 1989 5372A Clock Rate Independent Jitter Measurements for Digital Communications Systems 358-5 1990 5372A French Translation of AN 358-5 358-6 1989 5372A Characterizing Transient Timing Errors in Disk and Tape Drives 358-7 1989 5372A Analysing Phase-Locked Loop Transients in the Modulation Domain 358-8 1989 5372A Single Shot BPSK Signal Characterization 358-9 1989 5372A Modulation Domain Techniques for Measuring Complex Radar Signals 358-9 1991 5372A French Translation of AN 358-9 358-10 1989 5372A Characterizing Baker Coded Modulation in Radar Systems 358-11 1989 5372A Characterizing Shirp Coded Modulation in Radar Systems 358-12 1990 5371A-5372A French Translation of AN 358-12 358-13 1990 5372A Analysing Phase-Locked Loop Capture and Tracking Range http://www.hpmemory.org/ressources/resrc_an_01.htm It looks like AN358-3 is the one you are referring to. However, it is not listed on the Agilent site: 5372A Frequency and Time Interval Analyzer 1-12 of 12 Title/Description Date Type PDF 667 KB Analyzing Phase-Locked Loop Capture and Tracking Range (AN 358-13) PDF 658 KB Analyzing Phase-Locked Loop Transients in the Modulation Domain (AN 358-7) PDF 721 KB Characterizing Barker Coded Modulation in Radar Systems (AN 358-10) PDF 647 KB Characterizing Chirp Coded Modulation in Radar Systems (AN 358-11) PDF 634 KB Clock Rate Independent Jitter Measurements for Digital Communications Systems (AN 358-5) PDF 4.29 MB Frequency and Time Standards (AN 52) PDF 15.4 MB Fundamentals of Time and Frequency Standards (AN 52-1) PDF 897 KB Fundamentals of Time Interval Measurements (AN 200-3) PDF 713 KB Modulation Domain Techniques for Measuring Complex Radar Singals (AN 358-9) PDF 1.33 MB Simplify Frequency Stability Measurements with Built-in Allan Variance Analysis (AN 358-12) PDF 943 KB Single Shot BPSK Signal Characterization (AN 358-5) PDF 11.9 MB Timekeeping and Frequency Calibration (AN 52-2) and it does not show up in google. However, in order to do Phase Margin Analysis as described in the Katz paper, you must have access to signals that are internal to the phase detector. They are not accessible in the hard disk, so the only signals that could be used for the HP 5372 are the same clock and data signals that were used in AN 191-7: http://cp.literature.agilent.com/litweb/pdf/5952-7908.pdf Since the same signals are used, the resulting plots will be the same. As I described previously, they are useless for any kind of analytical measurements of the performance of the disk drive. Regards, Mike From dave.mallery at gmail.com Wed Jun 24 16:48:04 2009 From: dave.mallery at gmail.com (Dave Mallery) Date: Wed, 24 Jun 2009 10:48:04 -0600 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: References: Message-ID: <3010c9470906240948x334f7194mc5ba3d8d86f70d3d@mail.gmail.com> hi on my amd machines running ubuntu latest, the lady runs, but is invisibie.... perhaps toggling the cloaking feature.... thanks dave On Tue, Jun 23, 2009 at 12:08 PM, Mark Sims wrote: > > Lady Heather is undergoing her periodic trip to the beauty parlor. A few > new gratuitous features have already crept in: > * You can specify a time/date for the program to exit > * The satellite elevation shows if the satellite is rising or setting > * You can show the times in your local time zone > * Periods of holdover are flagged in the plot > * The tbolt version and serial info is written to the log file > * You can specify command line options in a .CFG file > > Now would be a good time to suggest any new features that you can't live > without... > _________________________________________________________________ > Microsoft brings you a new way to search the web. Try Bing? now > > http://www.bing.com?form=MFEHPG&publ=WLHMTAG&crea=TEXT_MFEHPG_Core_tagline_try_bing_1x1 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Dave Mallery, K5EN (ubuntu linux 9.04) HC31 Box 99E; Williamsburg, NM 87942 no gates... no windows! free at last! linux counter #64628 (since 1997) "People aren't as dumb as Microsoft needs them to be." --PJ, May 2007 From Murray.Greenman at rakon.com Wed Jun 24 19:07:40 2009 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Thu, 25 Jun 2009 07:07:40 +1200 Subject: [time-nuts] Long wave receiver ideas In-Reply-To: References: Message-ID: Marc, I endorse Leigh's suggestion. It is a very simple but effective solution. I use the SA602 myself. Used with an active whip antenna sensitivity is not a problem, and you can receive signals from around the world. As for the local oscillator, yes you can most certainly use the FE-5650A or FE-5680A, but I don't think that's necessary. If you have a receiver which has suitable stability and can receive 10MHz, then a very good solution is to drive the S602 with a 10MHz OCXO as the LO (the SA602 is very accommodating, and can act as VFO, XO or buffer for an external LO), or even drive it from a 10MHz GPSDO. Bear in mind that any phase noise or modulation will appear on the mixed output (and 1Hz modulation can be a problem with GPSDOs if you're not careful). There is a very neat technique which works well below about 500kHz to give extreme precision to reception. This is 'Clicklock' developed by Peter Martinez G3PLX. Essentially you can receive any signal which has ultra-low drift even if your receiver or converter has drift. It uses harmonics of a 1pps reference compared with the 1pps pulse itself to compensate for receiver drift, and all you need is a 1pps GPS signal and a PC with sound card. The software is then able to provide sufficient phase stability to integrate the received signal synchronously over many seconds, giving incredible sensitivity and bandwidths measured in milliHz. It has enabled me to discern the carrier (and hourly phase advance) of WWVB on 60kHz at a range of 8000km, and for my own 80uW EIRP transmission on 181kHz to be detected 500km away. See http://www.qsl.net/zl1bpu/ZL2AFP/CLICK/click.htm for more information and Clicklock software by Con Wassilief ZL2AFP. 73, Murray Greenman ZL1BPU From phk at phk.freebsd.dk Wed Jun 24 19:28:58 2009 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Wed, 24 Jun 2009 19:28:58 +0000 Subject: [time-nuts] Long wave receiver ideas In-Reply-To: Your message of "Thu, 25 Jun 2009 07:07:40 +1200." Message-ID: <17433.1245871738@critter.freebsd.dk> In message , "Murra y Greenman" writes: >There is a very neat technique which works well below about 500kHz to >give extreme precision to reception. This is 'Clicklock' developed by >Peter Martinez G3PLX. Am I right in assuming the only special thing here is how the measurement is performed ? The results look similar to what you would get with a lock-in amplifier ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk at FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. From tomknox at nist.gov Thu Jun 25 00:48:41 2009 From: tomknox at nist.gov (tomknox at nist.gov) Date: Wed, 24 Jun 2009 20:48:41 -0400 Subject: [time-nuts] Austron 2110 manual In-Reply-To: <20090403200407.1E685C5EA2C8@mailhost.idcomm.com> References: <20090403200407.1E685C5EA2C8@mailhost.idcomm.com> Message-ID: <20090624204841.291221awwo2c9rvt@webmail.nist.gov> HI Ship; I tracked down my 2110 manual. The manual is from about 1985/86 and appears complete. I hope this rev will work. I am looking forward to going thru it, you were over my head more then once today. I will bring it when we meet. Best Wishes; Thomas Knox NIST 4475 Whitney Place Boulder Colorado 80305 1-303-554-0307 tomknox at nist.gov Quoting Skip Withrow : > > Hello Time-Nuts, > > I am in need of a manual for the Austron 2110 Disciplined Frequency > Standard. Anyone have an electronic copy? I have already tried KO4BB's > site and BAMA. > > I would be more than happy to pay shipping so that I could copy/scan a > hard-copy if you have one. Guaranteed to be returned promptly. > > Regards, > Skip Withrow > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From jfor at quik.com Thu Jun 25 00:53:32 2009 From: jfor at quik.com (J. Forster) Date: Wed, 24 Jun 2009 17:53:32 -0700 (PDT) Subject: [time-nuts] Austron 2110 manual In-Reply-To: <20090624204841.291221awwo2c9rvt@webmail.nist.gov> References: <20090403200407.1E685C5EA2C8@mailhost.idcomm.com> <20090624204841.291221awwo2c9rvt@webmail.nist.gov> Message-ID: <1532.12.6.201.246.1245891212.squirrel@popacctsnew.quik.com> If you can arrange a scan, I'd like to get a copy of the .pdf. BTW, Dave at Artek Media might be interested in doing the scanning and making it available as he has done for lots of Tek and HP manuals. He does a nice job. -John ========= > HI Ship; > I tracked down my 2110 manual. The manual is from about 1985/86 and > appears complete. I hope this rev will work. I am looking forward to > going thru it, you were over my head more then once today. I will > bring it when we meet. > Best Wishes; > Thomas Knox > NIST > 4475 Whitney Place > Boulder Colorado 80305 > 1-303-554-0307 > tomknox at nist.gov > > > > Quoting Skip Withrow : > >> >> Hello Time-Nuts, >> >> I am in need of a manual for the Austron 2110 Disciplined Frequency >> Standard. Anyone have an electronic copy? I have already tried KO4BB's >> site and BAMA. >> >> I would be more than happy to pay shipping so that I could copy/scan a >> hard-copy if you have one. Guaranteed to be returned promptly. >> >> Regards, >> Skip Withrow >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From cfharris at erols.com Thu Jun 25 02:19:03 2009 From: cfharris at erols.com (Chuck Harris) Date: Wed, 24 Jun 2009 22:19:03 -0400 Subject: [time-nuts] Austron 2110 manual In-Reply-To: <1532.12.6.201.246.1245891212.squirrel@popacctsnew.quik.com> References: <20090403200407.1E685C5EA2C8@mailhost.idcomm.com> <20090624204841.291221awwo2c9rvt@webmail.nist.gov> <1532.12.6.201.246.1245891212.squirrel@popacctsnew.quik.com> Message-ID: <4A42DE97.2020704@erols.com> I loaned my copy to Brooke for scanning. There should be one on his PRC68.com website. -Chuck Harris J. Forster wrote: > If you can arrange a scan, I'd like to get a copy of the .pdf. > > BTW, Dave at Artek Media might be interested in doing the scanning and > making it available as he has done for lots of Tek and HP manuals. He does > a nice job. > > -John > > ========= > >> HI Ship; >> I tracked down my 2110 manual. The manual is from about 1985/86 and >> appears complete. I hope this rev will work. I am looking forward to >> going thru it, you were over my head more then once today. I will >> bring it when we meet. >> Best Wishes; >> Thomas Knox >> NIST >> 4475 Whitney Place >> Boulder Colorado 80305 >> 1-303-554-0307 >> tomknox at nist.gov >> >> >> >> Quoting Skip Withrow : >> >>> Hello Time-Nuts, >>> >>> I am in need of a manual for the Austron 2110 Disciplined Frequency >>> Standard. Anyone have an electronic copy? I have already tried KO4BB's >>> site and BAMA. >>> >>> I would be more than happy to pay shipping so that I could copy/scan a >>> hard-copy if you have one. Guaranteed to be returned promptly. >>> >>> Regards, >>> Skip Withrow >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From df6jb at ulrich-bangert.de Thu Jun 25 06:52:29 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 25 Jun 2009 08:52:29 +0200 Subject: [time-nuts] Introduction of Z38XX In-Reply-To: Message-ID: <84A284ED746F4A49B3A7A087A7FEBB5B@athlon> Gents, in the meantime I have received some feedback. Please read it with my answers in case you noticed something similar: > 1. The vertical scale has some issues. It goes down from 10-8 > to 10-23 and then goes up again to 10-7. Read the 10-23 as "near zero". Everything below should have a "-" sign, indicating negative values. I enclose a picture how it looks here. > The EFC value is remains fixed at > 65000. My Z3801 goes to EFC 696364 so stays at the top always. All scales are "autoscaling" and should follow whatever values you have. You mave have however put the autoscaling out of work by zooming into the grahics or by panning the graphics. Zooming is initiated by pressing the left mousebutton at the top left point of the area to be zoomed and then draw a white rectangle to the bottom right point of the area to be zoomed. Panning is initiated by pressing the right mouse button within the graphics and then move the mouse while the button is pressed. You can use both actions as often as you want and return to your initial screen by "reverse zoom" action, i.e. press the left mouse button anywhere in the graphics and move the mouse left and up while the button is pressed. A second possibility were that you have played around with the chart editor and switched the scale to a fixed value. In this case you can turn everything to the start values by termintaing the program and then start it again. All existing data will be read in again so will only loose one value or two > 2. The holdover unc. and sats the sat scale is not OK. It > seems to indicate twice the number of tracked sats and a high > number (76) of visible sats. First check whether the visible and tracked number of sats is shown correct in the main screen's status bar. If the error is already there then check in the parameters whether the "Where to look for data in the status screen" values are correct for you (You can count the lines in the receiver status screen). May be that I initialized these values wrong as long as no Z3801.Ini is available. 73 de Ulrich, DF6JB > -----Urspr?ngliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert > Gesendet: Dienstag, 23. Juni 2009 11:29 > An: Time nuts > Betreff: [time-nuts] Introduction of Z38XX > > > Gents, > > perhaps you have read that since a few days I am the owner of > a Z3805 bought on eBAy from fluke.I. > > The other day a friend of mine visited me and brought his > GPSCON with him to test it on my Z3805. As fluke.I had > pointed out, the GPSCON would work with the Z3805 but it > would not work really satisfying. The reason is that the > Z3801 has a 6 channel receiver and the Z3816 has a 8 channel > receiver, so GPSCON is simply not prepared to read more than > 8 sat data sets from the Z3805's status screen (which has a > 12 channel receiver). In addition, because the Z3805's status > screen uses more lines for the display of the additional sat > data sets GPSCON will miss the last three lines of the > z3805's status screen. > > This in conjunction with some other things encouraged me me > to write a z3805 tool of my own named Z38XX. Of course it > will handle z3801s and z3816s as well. It is far from being > complete but you can get a good impression of it by > downloading it from the usual place > > http://www.ulrich-bangert.de/html/downloads.html > > Z38XX talks to the Z3801/5/16 with a exact 10 s time base > which means the PPS TI delivered can be used for the > computation of Allan deviation (and other measures) of the > internal phase comparator with a Tau0 = 10 s (which is done > internally in Z38XX similar as in Lady Heather). > > The sat's horizont line in the Azimuth / Elevation chart will > look strange in the first hours after program start. Give it > some days until it looks as attched or even better. > > Have fun > > Ulrich Bangert > www.ulrich-bangert.de > Ortholzer Weg 1 > 27243 Gross Ippener > From df6jb at ulrich-bangert.de Thu Jun 25 13:24:29 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Thu, 25 Jun 2009 15:24:29 +0200 Subject: [time-nuts] Introduction of Z38XX In-Reply-To: Message-ID: <8508D72353754344B57A7867210D674F@athlon> Gents, the first users of Z38XX have found some issues with the software. I hope I have already fixed them but I want to wait for the feedback. ASAP I will inform you wheter the new version is free of this issues. Best regards Ulrich Bangert > -----Urspr?ngliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Ulrich Bangert > Gesendet: Dienstag, 23. Juni 2009 11:29 > An: Time nuts > Betreff: [time-nuts] Introduction of Z38XX > > > Gents, > > perhaps you have read that since a few days I am the owner of > a Z3805 bought on eBAy from fluke.I. > > The other day a friend of mine visited me and brought his > GPSCON with him to test it on my Z3805. As fluke.I had > pointed out, the GPSCON would work with the Z3805 but it > would not work really satisfying. The reason is that the > Z3801 has a 6 channel receiver and the Z3816 has a 8 channel > receiver, so GPSCON is simply not prepared to read more than > 8 sat data sets from the Z3805's status screen (which has a > 12 channel receiver). In addition, because the Z3805's status > screen uses more lines for the display of the additional sat > data sets GPSCON will miss the last three lines of the > z3805's status screen. > > This in conjunction with some other things encouraged me me > to write a z3805 tool of my own named Z38XX. Of course it > will handle z3801s and z3816s as well. It is far from being > complete but you can get a good impression of it by > downloading it from the usual place > > http://www.ulrich-bangert.de/html/downloads.html > > Z38XX talks to the Z3801/5/16 with a exact 10 s time base > which means the PPS TI delivered can be used for the > computation of Allan deviation (and other measures) of the > internal phase comparator with a Tau0 = 10 s (which is done > internally in Z38XX similar as in Lady Heather). > > The sat's horizont line in the Azimuth / Elevation chart will > look strange in the first hours after program start. Give it > some days until it looks as attched or even better. > > Have fun > > Ulrich Bangert > www.ulrich-bangert.de > Ortholzer Weg 1 > 27243 Gross Ippener > From tomknox at nist.gov Thu Jun 25 15:42:54 2009 From: tomknox at nist.gov (tomknox at nist.gov) Date: Thu, 25 Jun 2009 11:42:54 -0400 Subject: [time-nuts] Have Austron 2110 manual, looking for Datum 2110C manual In-Reply-To: <1532.12.6.201.246.1245891212.squirrel@popacctsnew.quik.com> References: <20090403200407.1E685C5EA2C8@mailhost.idcomm.com> <20090624204841.291221awwo2c9rvt@webmail.nist.gov> <1532.12.6.201.246.1245891212.squirrel@popacctsnew.quik.com> Message-ID: <20090625114254.12365zwe6o0vac5a@webmail.nist.gov> Hi John; I will see what I can do. I will also make a few additional hard copies. It may be a week or so, Skip has a incomplete copy that I believe it is a different REV and it would be nice to combine the two. Does any one have a 2110C manual? Thomas Knox NIST 4475 Whitney Place Boulder Colorado 80305 1-303-554-0307 tomknox at nist.gov Quoting "J. Forster" : > If you can arrange a scan, I'd like to get a copy of the .pdf. > > BTW, Dave at Artek Media might be interested in doing the scanning and > making it available as he has done for lots of Tek and HP manuals. He does > a nice job. > > -John > > ========= > >> HI Ship; >> I tracked down my 2110 manual. The manual is from about 1985/86 and >> appears complete. I hope this rev will work. I am looking forward to >> going thru it, you were over my head more then once today. I will >> bring it when we meet. >> Best Wishes; >> Thomas Knox >> NIST >> 4475 Whitney Place >> Boulder Colorado 80305 >> 1-303-554-0307 >> tomknox at nist.gov >> >> >> >> Quoting Skip Withrow : >> >>> >>> Hello Time-Nuts, >>> >>> I am in need of a manual for the Austron 2110 Disciplined Frequency >>> Standard. Anyone have an electronic copy? I have already tried KO4BB's >>> site and BAMA. >>> >>> I would be more than happy to pay shipping so that I could copy/scan a >>> hard-copy if you have one. Guaranteed to be returned promptly. >>> >>> Regards, >>> Skip Withrow >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From jpawlan at pawlan.com Thu Jun 25 16:08:42 2009 From: jpawlan at pawlan.com (Jeffrey Pawlan) Date: Thu, 25 Jun 2009 09:08:42 -0700 (PDT) Subject: [time-nuts] Have Austron 2110 manual, looking for Datum 2110C manual In-Reply-To: <20090625114254.12365zwe6o0vac5a@webmail.nist.gov> References: <20090403200407.1E685C5EA2C8@mailhost.idcomm.com> <20090624204841.291221awwo2c9rvt@webmail.nist.gov> <1532.12.6.201.246.1245891212.squirrel@popacctsnew.quik.com> <20090625114254.12365zwe6o0vac5a@webmail.nist.gov> Message-ID: Tom and John, I am still using my Austron loran c receiver with an austron 2110 disciplined frequency standard. I have made several modifications as well as repairs to both units. I purchased the manual from Austron when they were still in business. I think it was around $125. I looked at the titlepage and it is revision L and was from Sept 1988. I do not know whether Datum revised it after that. Regards, Jeffrey Pawlan Pawlan Communications From Murray.Greenman at rakon.com Thu Jun 25 18:39:43 2009 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Fri, 26 Jun 2009 06:39:43 +1200 Subject: [time-nuts] Long Wave Receiver ideas In-Reply-To: References: Message-ID: Poul, Regarding Clicklock. Yes, in a sense Clicklock is a lock-in amplifier. However the really special thing is that it completely compensates (within reason) for the drift in ALL the oscillators in your receiver and/or converter, so that it becomes GPS locked. It does this by comparing the phase of harmonics of 1pps as they arrive at the receiver with the phase of the 1pps itself. It uses an NCO to down-convert to zero Hz. There is obviously an advancing phase with frequency in the 1pps harmonics if the down-converted frequency is high, and the NCO is shifted to compensate. It will also therefore also compensate for changes in phase and delay through the preamp, feedline and receiver filters. If you look at the examples on the reference I gave, http://www.qsl.net/zl1bpu/ZL2AFP/CLICK/click.htm, you'll see there's a phase plot which shows the integration of I and Q samples, plus phase and power plots which are achieved by maths from the I and Q followed by 'leaky integrators'. That bit was my contribution. The whole idea originated with Peter G3PLX, the source of many good ideas. Give it a try - it's quite a tricky bit of software to drive. Regards, Murray Greenman ZL1BPU From iain at g7iii.net Thu Jun 25 18:47:57 2009 From: iain at g7iii.net (Iain Young) Date: Thu, 25 Jun 2009 19:47:57 +0100 Subject: [time-nuts] Z3805 vs Z3816/Z3801 Message-ID: <4A43C65D.6080403@g7iii.net> Hi All, I'm thinking about adding a Z3805 to my existing Z3816 (once I get the 3816 up and running once the sparky has finished putting electricity in the garage!) However, I have a few questions that I need to answer before I actually make that decision, and as I'm sure those of you who have a Z3805 know, finding the manual is...a challenge... Anyway, does anyone know: a) The Power requirements. The 3801 and 3816 differ in Voltage requirements as I understand it, anyone able to tell me what the 3805 needs/wants/likes to be fed ? b) Pictures I've seen appear to show BNC rather than SMA connectors, can someone with 3805 confirm ? (Not that it's such a massive issue, but extra cables or converters required...) c) 16 channel GPS RX is great. But anyone know if it wants to feed 3.3V or 5V up to the antenna ? d) Anyone know if it works with the Type 26 NTP reference clock driver ? Anyone actually have it running this way ? Finally, a generic question about all 3 of these HP/Agilent/Symmetricon devices: I know the PPS spec -isn't- at RS-232 levels, however nor is the Garmin GPS-18, and that worked raw for me. Has anyone tried just feeding the PPS signal from a 3801/05/16 into the DCD pin of a serial port ? Iain From hmurray at megapathdsl.net Thu Jun 25 19:22:56 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Thu, 25 Jun 2009 12:22:56 -0700 Subject: [time-nuts] Z3805 vs Z3816/Z3801 In-Reply-To: Message from Iain Young of "Thu, 25 Jun 2009 19:47:57 BST." <4A43C65D.6080403@g7iii.net> Message-ID: <20090625192257.E1DAABCEF@ip-64-139-1-69.sjc.megapath.net> > Finally, a generic question about all 3 of these HP/Agilent/ > Symmetricon devices: I know the PPS spec -isn't- at RS-232 levels, > however nor is the Garmin GPS-18, and that worked raw for me. Has > anyone tried just feeding the PPS signal from a 3801/05/16 into the > DCD pin of a serial port ? I don't know about the 3805 or 3816, but the 3801 is RS-442 rather than RS-232. It's all setup to talk RS-232, but you have to take it apart and shuffle some 0-ohm resistors. While you are in there, you can make a similar patch for the PPS signal. http://support.ntp.org/bin/view/Support/ConfiguringHPZ3801ARefclocks -- These are my opinions, not necessarily my employer's. I hate spam. From alan.melia at btinternet.com Thu Jun 25 23:21:53 2009 From: alan.melia at btinternet.com (Alan Melia) Date: Fri, 26 Jun 2009 00:21:53 +0100 Subject: [time-nuts] Long Wave Receiver ideas References: Message-ID: <005501c9f5ed$20a04b40$0900a8c0@AM> Murray, I dont remember the detail but we used Clicklock a few time on LF and I think Steve MacDonald VE7SL built a GUI front end to make it a bit more appealing. He has a web site. I dont seem to have it loaded on this machine any longer. Alan G3NYK ----- Original Message ----- From: "Murray Greenman" To: Sent: Thursday, June 25, 2009 7:39 PM Subject: [time-nuts] Long Wave Receiver ideas > Poul, > Regarding Clicklock. Yes, in a sense Clicklock is a lock-in amplifier. > However the really special thing is that it completely compensates > (within reason) for the drift in ALL the oscillators in your receiver > and/or converter, so that it becomes GPS locked. It does this by > comparing the phase of harmonics of 1pps as they arrive at the receiver > with the phase of the 1pps itself. It uses an NCO to down-convert to > zero Hz. There is obviously an advancing phase with frequency in the > 1pps harmonics if the down-converted frequency is high, and the NCO is > shifted to compensate. > > It will also therefore also compensate for changes in phase and delay > through the preamp, feedline and receiver filters. > > If you look at the examples on the reference I gave, > http://www.qsl.net/zl1bpu/ZL2AFP/CLICK/click.htm, you'll see there's a > phase plot which shows the integration of I and Q samples, plus phase > and power plots which are achieved by maths from the I and Q followed by > 'leaky integrators'. That bit was my contribution. The whole idea > originated with Peter G3PLX, the source of many good ideas. > > Give it a try - it's quite a tricky bit of software to drive. > > Regards, > Murray Greenman ZL1BPU > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From rdarlington at gmail.com Fri Jun 26 01:07:48 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Thu, 25 Jun 2009 19:07:48 -0600 Subject: [time-nuts] Datachron, Inc. Message-ID: Hi guys, What happened to Datachron? I'm trying to dig up a manual for an IRIG-B display, Datachron model 3700-205 that I just picked up on eBay: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290323873289 It came in today and powers up, and looks just like it does in the pictures. Doesn't seem to do anything more than that, either! I'm trying to drive it using NMEATime software. It seems that no matter what amplitude I'm using, the display does nothing. I reseated all IC chips, wiggled connectors, the standard sort of thing. No change. Datachron appears to have gone out of business, but I'm hopeful that somebody just bought them, changed their name, and has a hidden supply of manuals somewhere. Thanks, Bob, N3XKB From kyrrin at bluefeathertech.com Fri Jun 26 01:20:26 2009 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Thu, 25 Jun 2009 18:20:26 -0700 Subject: [time-nuts] Datachron, Inc. In-Reply-To: References: Message-ID: <200906251820260968.07732CC1@192.168.42.129> There were two popular ways to transmit IRIG time code: DC (TTL) level and AM on a 1kHz audio carrier. Your display might be jumpered for DC level code. Open it up, look around the input connector. I'll bet there's an internal switch or jumper to select DC or audio carrier. Happy tweaking. *********** REPLY SEPARATOR *********** On 25-Jun-09 at 19:07 Robert Darlington wrote: >Hi guys, > >What happened to Datachron? I'm trying to dig up a manual for an IRIG-B >display, Datachron model 3700-205 that I just picked up on eBay: > >http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290323873289 > >It came in today and powers up, and looks just like it does in the >pictures. Doesn't seem to do anything more than that, either! I'm trying >to drive it using NMEATime software. It seems that no matter what >amplitude >I'm using, the display does nothing. I reseated all IC chips, wiggled >connectors, the standard sort of thing. No change. Datachron appears to >have gone out of business, but I'm hopeful that somebody just bought them, >changed their name, and has a hidden supply of manuals somewhere. > >Thanks, >Bob, N3XKB >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > >__________ Information from ESET Smart Security, version of virus >signature database 4189 (20090625) __________ > >The message was checked by ESET Smart Security. > >http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "Quid Malmborg in Plano..." From jfor at quik.com Fri Jun 26 01:21:40 2009 From: jfor at quik.com (J. Forster) Date: Thu, 25 Jun 2009 18:21:40 -0700 (PDT) Subject: [time-nuts] Datachron, Inc. In-Reply-To: References: Message-ID: <2458.12.6.201.71.1245979300.squirrel@popacctsnew.quik.com> Are you sure you are really feeding it IRIG-B? You might try looking at your TC signal with a 'scope and seeing if it meets the IRIG spec. Such a test would bisect the problem. FWIW, -John ========== > Hi guys, > > What happened to Datachron? I'm trying to dig up a manual for an IRIG-B > display, Datachron model 3700-205 that I just picked up on eBay: > > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290323873289 > > It came in today and powers up, and looks just like it does in the > pictures. Doesn't seem to do anything more than that, either! I'm > trying > to drive it using NMEATime software. It seems that no matter what > amplitude > I'm using, the display does nothing. I reseated all IC chips, wiggled > connectors, the standard sort of thing. No change. Datachron appears to > have gone out of business, but I'm hopeful that somebody just bought them, > changed their name, and has a hidden supply of manuals somewhere. > > Thanks, > Bob, N3XKB > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > From rdarlington at gmail.com Fri Jun 26 01:24:30 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Thu, 25 Jun 2009 19:24:30 -0600 Subject: [time-nuts] Datachron, Inc. In-Reply-To: <2458.12.6.201.71.1245979300.squirrel@popacctsnew.quik.com> References: <2458.12.6.201.71.1245979300.squirrel@popacctsnew.quik.com> Message-ID: I'm 99% sure. What I see on the scope looks like what I see in the spec. AM modulated signal, but I didn't actually verify the timings yet. I figured that even if I was off a bit, that *something* should change on the display. Maybe this is a poor assumption. I'm off to find a jumper... -Bob On Thu, Jun 25, 2009 at 7:21 PM, J. Forster wrote: > Are you sure you are really feeding it IRIG-B? You might try looking at > your TC signal with a 'scope and seeing if it meets the IRIG spec. > > Such a test would bisect the problem. > > FWIW, > -John > > ========== > > > Hi guys, > > > > What happened to Datachron? I'm trying to dig up a manual for an IRIG-B > > display, Datachron model 3700-205 that I just picked up on eBay: > > > > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290323873289 > > > > It came in today and powers up, and looks just like it does in the > > pictures. Doesn't seem to do anything more than that, either! I'm > > trying > > to drive it using NMEATime software. It seems that no matter what > > amplitude > > I'm using, the display does nothing. I reseated all IC chips, wiggled > > connectors, the standard sort of thing. No change. Datachron appears > to > > have gone out of business, but I'm hopeful that somebody just bought > them, > > changed their name, and has a hidden supply of manuals somewhere. > > > > Thanks, > > Bob, N3XKB > > _______________________________________________ > > time-nuts mailing list -- time-nuts at febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From rdarlington at gmail.com Fri Jun 26 01:50:48 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Thu, 25 Jun 2009 19:50:48 -0600 Subject: [time-nuts] Datachron, Inc. In-Reply-To: References: <2458.12.6.201.71.1245979300.squirrel@popacctsnew.quik.com> Message-ID: The only jumper I could see is on the display board. It appears to just be a segment test. I verified that it's running at 1kHz modulation against a frequency synthesizer on the scope. Amplitudes look fine. I tried everything from about 0.1 V peak to peak to about 5 volts peak to peak. I'll keep looking around for a manual. I suspect Bruce might be right about it wanting TTL without the carrier. Thanks, Bob On Thu, Jun 25, 2009 at 7:24 PM, Robert Darlington wrote: > I'm 99% sure. What I see on the scope looks like what I see in the spec. > AM modulated signal, but I didn't actually verify the timings yet. I > figured that even if I was off a bit, that *something* should change on the > display. Maybe this is a poor assumption. I'm off to find a jumper... > > -Bob > > > On Thu, Jun 25, 2009 at 7:21 PM, J. Forster wrote: > >> Are you sure you are really feeding it IRIG-B? You might try looking at >> your TC signal with a 'scope and seeing if it meets the IRIG spec. >> >> Such a test would bisect the problem. >> >> FWIW, >> -John >> >> ========== >> >> > Hi guys, >> > >> > What happened to Datachron? I'm trying to dig up a manual for an IRIG-B >> > display, Datachron model 3700-205 that I just picked up on eBay: >> > >> > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290323873289 >> > >> > It came in today and powers up, and looks just like it does in the >> > pictures. Doesn't seem to do anything more than that, either! I'm >> > trying >> > to drive it using NMEATime software. It seems that no matter what >> > amplitude >> > I'm using, the display does nothing. I reseated all IC chips, wiggled >> > connectors, the standard sort of thing. No change. Datachron appears >> to >> > have gone out of business, but I'm hopeful that somebody just bought >> them, >> > changed their name, and has a hidden supply of manuals somewhere. >> > >> > Thanks, >> > Bob, N3XKB >> > _______________________________________________ >> > time-nuts mailing list -- time-nuts at febo.com >> > To unsubscribe, go to >> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> > and follow the instructions there. >> > >> > >> >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts at febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > From w9ac at arrl.net Fri Jun 26 02:49:12 2009 From: w9ac at arrl.net (Paul Christensen) Date: Thu, 25 Jun 2009 22:49:12 -0400 Subject: [time-nuts] Brandywine GPS-4 Software? Message-ID: Anyone know if there's a software control program available for the Brandywine GPS-4 -- either through Brandywine or a third-party? Thanks! Paul, W9AC From rdarlington at gmail.com Fri Jun 26 03:57:58 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Thu, 25 Jun 2009 21:57:58 -0600 Subject: [time-nuts] Datachron, Inc. In-Reply-To: References: <2458.12.6.201.71.1245979300.squirrel@popacctsnew.quik.com> Message-ID: There is a 44 pin chip that seems to have had a pin broken off. In my attempts to short this to an already mangled chip socket, I managed to let some smoke out. Oh well, now I have a pretty metal paperweight that I may convert over to using NMEA signals from a gps. Thanks guys, -Bob On Thu, Jun 25, 2009 at 7:50 PM, Robert Darlington wrote: > The only jumper I could see is on the display board. It appears to just be > a segment test. I verified that it's running at 1kHz modulation against a > frequency synthesizer on the scope. Amplitudes look fine. I tried > everything from about 0.1 V peak to peak to about 5 volts peak to peak. > I'll keep looking around for a manual. I suspect Bruce might be right about > it wanting TTL without the carrier. > > Thanks, > Bob > > > On Thu, Jun 25, 2009 at 7:24 PM, Robert Darlington wrote: > >> I'm 99% sure. What I see on the scope looks like what I see in the spec. >> AM modulated signal, but I didn't actually verify the timings yet. I >> figured that even if I was off a bit, that *something* should change on the >> display. Maybe this is a poor assumption. I'm off to find a jumper... >> >> -Bob >> >> >> On Thu, Jun 25, 2009 at 7:21 PM, J. Forster wrote: >> >>> Are you sure you are really feeding it IRIG-B? You might try looking at >>> your TC signal with a 'scope and seeing if it meets the IRIG spec. >>> >>> Such a test would bisect the problem. >>> >>> FWIW, >>> -John >>> >>> ========== >>> >>> > Hi guys, >>> > >>> > What happened to Datachron? I'm trying to dig up a manual for an >>> IRIG-B >>> > display, Datachron model 3700-205 that I just picked up on eBay: >>> > >>> > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290323873289 >>> > >>> > It came in today and powers up, and looks just like it does in the >>> > pictures. Doesn't seem to do anything more than that, either! I'm >>> > trying >>> > to drive it using NMEATime software. It seems that no matter what >>> > amplitude >>> > I'm using, the display does nothing. I reseated all IC chips, wiggled >>> > connectors, the standard sort of thing. No change. Datachron appears >>> to >>> > have gone out of business, but I'm hopeful that somebody just bought >>> them, >>> > changed their name, and has a hidden supply of manuals somewhere. >>> > >>> > Thanks, >>> > Bob, N3XKB >>> > _______________________________________________ >>> > time-nuts mailing list -- time-nuts at febo.com >>> > To unsubscribe, go to >>> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> > and follow the instructions there. >>> > >>> > >>> >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts at febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> > From df6jb at ulrich-bangert.de Fri Jun 26 06:50:34 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Fri, 26 Jun 2009 08:50:34 +0200 Subject: [time-nuts] Z3805 vs Z3816/Z3801 In-Reply-To: <4A43C65D.6080403@g7iii.net> Message-ID: <8B7813AAC16742AEA31F0D67B218C30B@athlon> Iain, I own a Z3805 but have no manual for it, so the following is from my experience only: > a) The Power requirements. The 3801 and 3816 differ in > Voltage requirements as I understand it, anyone able to tell > me what the 3805 needs/wants/likes to be fed ? There seem to be 24 V versions and 48 V versions around. Mine is a 24 V version. The power connector is male XLR connector as used in audio applications. > b) Pictures I've seen appear to show BNC rather than SMA > connectors, can someone with 3805 confirm ? (Not that it's > such a massive issue, but extra cables or converters required...) Mine has 2 10 MHz and 2 PPS outputs via BNC connectors. Antenna connector is N-type. There are two 25 pin male Sub-D connectors, one of which is a RS232 with DTE pinning > c) 16 channel GPS RX is great. But anyone know if it wants to > feed 3.3V or 5V up to the antenna ? My guess is 5 V. Perhaps someone has measured it. I am currently experimenting with mine in software and do at this point not want to disconnect the antenna cable to measure. > d) Anyone know if it works with the Type 26 NTP reference > clock driver ? Anyone actually have it running this way ? The only difference in communication against a Z3801 that I could find as far comes from the 16 channel receiver: It needs more lines in the status screen to list all tracked sats. So my guess is that it should run with any software that does not rely TOO strong on positions on the status screen. Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Iain Young > Gesendet: Donnerstag, 25. Juni 2009 20:48 > An: time-nuts at febo.com > Betreff: [time-nuts] Z3805 vs Z3816/Z3801 > > > Hi All, > > I'm thinking about adding a Z3805 to my existing Z3816 (once > I get the 3816 up and running once the sparky has finished > putting electricity in the garage!) > > However, I have a few questions that I need to answer before > I actually make that decision, and as I'm sure those of you > who have a Z3805 know, finding the manual is...a challenge... > > Anyway, does anyone know: > > a) The Power requirements. The 3801 and 3816 differ in > Voltage requirements as I understand it, anyone able to tell > me what the 3805 needs/wants/likes to be fed ? > > b) Pictures I've seen appear to show BNC rather than SMA > connectors, can someone with 3805 confirm ? (Not that it's > such a massive issue, but extra cables or converters required...) > > c) 16 channel GPS RX is great. But anyone know if it wants to > feed 3.3V or 5V up to the antenna ? > > d) Anyone know if it works with the Type 26 NTP reference > clock driver ? Anyone actually have it running this way ? > > > Finally, a generic question about all 3 of these > HP/Agilent/Symmetricon > devices: I know the PPS spec -isn't- at RS-232 levels, > however nor is the Garmin GPS-18, and that worked raw for me. > Has anyone tried just feeding the PPS signal from a > 3801/05/16 into the DCD pin of a serial port ? > > > Iain > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From vilgotch at bigpond.net.au Fri Jun 26 06:58:47 2009 From: vilgotch at bigpond.net.au (Morris Odell) Date: Fri, 26 Jun 2009 16:58:47 +1000 Subject: [time-nuts] time-nuts Digest, Vol 59, Issue 85 References: Message-ID: <2F04A7806FC04EDBA67778E4DBDE87CB@Morris1> I bought a manual from them a couple of years ago but on checking their website www.datachroninc.com it appears that the domain name is for sale. They lasted a long time but it looks like they've gone... Regarding IRIG, there are several different flavours - IRIG A, B, C etc all with different data rates and frame specs. My ancient DTL driven Datachron has a selector switch on the front panel - maybe yours has one too, hidden somewhere Morris > From: Robert Darlington > Subject: [time-nuts] Datachron, Inc. > To: Discussion of precise time and frequency measurement > > Message-ID: > > Content-Type: text/plain; charset=ISO-8859-1 > > Hi guys, > > What happened to Datachron? From hmurray at megapathdsl.net Fri Jun 26 08:29:38 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Fri, 26 Jun 2009 01:29:38 -0700 Subject: [time-nuts] Z3805 vs Z3816/Z3801 Message-ID: <20090626082939.353C9BCEF@ip-64-139-1-69.sjc.megapath.net> >> d) Anyone know if it works with the Type 26 NTP reference >> clock driver ? Anyone actually have it running this way ? > The only difference in communication against a Z3801 that I could find > as far comes from the 16 channel receiver: It needs more lines in the > status screen to list all tracked sats. So my guess is that it should > run with any software that does not rely TOO strong on positions on > the status screen. The HP driver in ntpd sends an occasional ":PTIME:TCODE?\" and expects to get a format 2 response. I'd have to check the code to be sure of the details. There is an option that I'm not familiar with to log the status screen. It expects 24x80 characters. If something similar to a Z3801 has a different size screen we should be able to work out something.... That's assuming it works without logging the status screen. -- These are my opinions, not necessarily my employer's. I hate spam. From df6jb at ulrich-bangert.de Fri Jun 26 11:35:41 2009 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Fri, 26 Jun 2009 13:35:41 +0200 Subject: [time-nuts] Z3805 vs Z3816/Z3801 In-Reply-To: <20090626082939.353C9BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: Hal, > The HP driver in ntpd sends an occasional ":PTIME:TCODE?\" > and expects to get > a format 2 response. I'd have to check the code to be sure > of the details. I am going to use this command myself and will be able to tell within a few hours whether that works on a Z3805 or not. Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Hal Murray > Gesendet: Freitag, 26. Juni 2009 10:30 > An: time-nuts at febo.com > Betreff: Re: [time-nuts] Z3805 vs Z3816/Z3801 > > > >> d) Anyone know if it works with the Type 26 NTP reference > >> clock driver ? Anyone actually have it running this way ? > > > The only difference in communication against a Z3801 that I > could find > > as far comes from the 16 channel receiver: It needs more > lines in the > > status screen to list all tracked sats. So my guess is that > it should > > run with any software that does not rely TOO strong on positions on > > the status screen. > > The HP driver in ntpd sends an occasional ":PTIME:TCODE?\" > and expects to get > a format 2 response. I'd have to check the code to be sure > of the details. > > There is an option that I'm not familiar with to log the > status screen. It > expects 24x80 characters. If something similar to a Z3801 > has a different > size screen we should be able to work out something.... > That's assuming it > works without logging the status screen. > > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From iovane at inwind.it Fri Jun 26 23:25:57 2009 From: iovane at inwind.it (iovane at inwind.it) Date: Sat, 27 Jun 2009 01:25:57 +0200 Subject: [time-nuts] Orbiting crystals Message-ID: Time-nuts, this post wouldn't be merely speculative, I have an actual interest in knowing if what I'm going to ask is possible. As it has already been discussed here, crystals may jump in frequency. If I recall, about 20% of good quality crystals are prone to jumping, but a crystal that used to jump might not jump anymore, a crystal that never jumped might jump in the future, and so on. The trace of a disciplined (atomic or GPS) jumping crystal shows spikes (because it is soon steered), while the trace of its control voltage shows permanent changes in level. Well, I thought it is legitimate to assume that orbiting crystals, namely the ones disciplined by caesium aboard GPS satellites, are not extraneous to the issue. And here is the question: may a time-nuts grade equipment detect this? The answer would not be simple. In the majority of cases we get from our multichannel GPSDO the 1 PPS pulse. How may the pulse be affected by the spike in frequency of a single orbiting crystal? I know this list is also populated by qualified professionals, and hope to get for sure one of the following conclusions: -crystals aboard GPS satellites do not jump at all; -if they do, time-nuts can't detect this; -time-nuts can detect jumps, but can't identify the jumping satellite; -time-nuts can detect jumps, and can identify the jumping satellite; Thanks. Antonio I8IOV From swithrow at alum.mit.edu Sat Jun 27 01:34:03 2009 From: swithrow at alum.mit.edu (Skip Withrow) Date: Fri, 26 Jun 2009 19:34:03 -0600 Subject: [time-nuts] Loosing for Datum/Symmetricom PRS-50 Information Message-ID: <4A45770B.7020403@alum.mit.edu> Is there a time-nut out there with any information on the Datum PRS-50 Cesium Primary Reference Source (spec sheets, User's Manual, command set)? I can find a reference to the user manual on the Symmetricom site, but when I click on it all that comes up are other User Manuals with the PRS-50 missing. Thanks in advance for any help. Regards, Skip Withrow From SAIDJACK at aol.com Sat Jun 27 04:46:30 2009 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Sat, 27 Jun 2009 00:46:30 EDT Subject: [time-nuts] Orbiting crystals Message-ID: Hi Antonio, not an expert on space qualified crystals, but I would think that in general Cesium and Rubidium crystals would be steered very quickly (within seconds?) to correct for any crystal jumps that surely will happen even, or especially in space. In a GPSDO, we generally only have one correction pulse per second from the GPS, and that one is even noisy and needs to be filtered. In an atomic clock, we can steer the crystal without this 1Hz limit. A good gps receiver will use over-determination and not use a single sat to generate the 1PPS. And even then a GPS 1PPS is expected to be noisy. Bye, Said In a message dated 6/26/2009 16:26:22 Pacific Daylight Time, iovane at inwind.it writes: this post wouldn't be merely speculative, I have an actual interest in knowing if what I'm going to ask is possible. As it has already been discussed here, crystals may jump in frequency. If I recall, about 20% of good quality crystals are prone to jumping, but a crystal that used to jump might not jump anymore, a crystal that never jumped might jump in the future, and so on. From w9ac at arrl.net Sat Jun 27 13:15:51 2009 From: w9ac at arrl.net (Paul Christensen) Date: Sat, 27 Jun 2009 09:15:51 -0400 Subject: [time-nuts] Z3801A Schematic Message-ID: <175155FB55D74909A646CBBC9870D873@DBTOA000> Looking for a schematic of the Z3801? I'm primarily interested in the power supply section. Anyone know an on-line source? I've been looking with no success. Tnx! Paul, W9AC From magnus at rubidium.dyndns.org Sat Jun 27 13:39:53 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 27 Jun 2009 15:39:53 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: Message-ID: <4A462129.4020603@rubidium.dyndns.org> iovane at inwind.it skrev: > Time-nuts, > > this post wouldn't be merely speculative, I have an actual > interest in knowing if what I'm going to ask is possible. > As it has already been discussed here, crystals may jump in > frequency. If I recall, about 20% of good quality crystals are > prone to jumping, but a crystal that used to jump might not > jump anymore, a crystal that never jumped might jump in the > future, and so on. To the best of my knowledge, it is due to strain defects which releases themselfs. Annealing is used to reduce stress. I am sure we have some that could comment on it's use in (deep) space programmes. > The trace of a disciplined (atomic or GPS) jumping crystal > shows spikes (because it is soon steered), while the trace of > its control voltage shows permanent changes in level. > Well, I thought it is legitimate to assume that orbiting > crystals, namely the ones disciplined by caesium aboard GPS > satellites, are not extraneous to the issue. > And here is the question: may a time-nuts grade equipment > detect this? > The answer would not be simple. In the majority of cases we > get from our multichannel GPSDO the 1 PPS pulse. How may the > pulse be affected by the spike in frequency of a single > orbiting crystal? > I know this list is also populated by qualified professionals, > and hope to get for sure one of the following conclusions: > -crystals aboard GPS satellites do not jump at all; I think there could be some interesting articles to dig up on that. I expect them to be conservative and use annealed crystals, so if there is jumps, they are rare occasions. I know that effects of the time-pieces have been reported. You should recall that there is several individual clocks. I expect the telemetry data to include a myriad of parameters of the clocks, so an oscillator frequency jumped should not be missed. The time-constants of the lock-up loops should give the oscillator some time of it own before it is pulled back into frequency, so that short-term deviation should be detectable. > -if they do, time-nuts can't detect this; > -time-nuts can detect jumps, but can't identify the jumping > satellite; > -time-nuts can detect jumps, and can identify the jumping > satellite; Depends on how you are rigged up. If you have propper L1/L2 receiver locked to a cesium and do propper RINEX dumping and analysis of the result, you should be able to see the resulting phase shift-dance when it occurs. However, you must be able to rule out other effects such as multipath and scintilation. Multiple observations of the same effect aids in that process. The resolution available in these receivers should be more than sufficient to detect such a jump, if it occurs. Cheers, Magnus From GandalfG8 at aol.com Sat Jun 27 14:53:53 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sat, 27 Jun 2009 10:53:53 EDT Subject: [time-nuts] Z3801A Schematic Message-ID: In a message dated 27/06/2009 14:16:27 GMT Daylight Time, w9ac at arrl.net writes: Looking for a schematic of the Z3801? I'm primarily interested in the power supply section. Anyone know an on-line source? I've been looking with no success. Tnx! ---------------- Hi Paul There don't seem to have been any "official" schematics issued for the Z3801A but there was a user traced schematic for the PSU posted online some time ago. I've just checked the URL and it's no longer valid but I have the files archived, web page, schematics, and component notes, and have zipped them into a single file of 2.5MB. If you can confirm your ARRL address is ok for attachments of that size I'll email it to you direct. regards Nigel GM8PZR From w9ac at arrl.net Sat Jun 27 14:58:10 2009 From: w9ac at arrl.net (Paul Christensen) Date: Sat, 27 Jun 2009 10:58:10 -0400 Subject: [time-nuts] Z3801A Schematic References: Message-ID: <08BAB289648E4701B85162CE6A1F6673@DBTOA000> Nigel, Yes, please attach and send to my ARRL address. Tnx! Paul, W9AC ----- Original Message ----- From: To: Sent: Saturday, June 27, 2009 10:53 AM Subject: Re: [time-nuts] Z3801A Schematic > In a message dated 27/06/2009 14:16:27 GMT Daylight Time, w9ac at arrl.net > writes: > > Looking for a schematic of the Z3801? I'm primarily interested in the > power > supply section. Anyone know an on-line source? I've been looking with > no > success. Tnx! > ---------------- > > > Hi Paul > > There don't seem to have been any "official" schematics issued for the > Z3801A but there was a user traced schematic for the PSU posted online > some > time ago. > I've just checked the URL and it's no longer valid but I have the files > archived, web page, schematics, and component notes, and have zipped them > into > a single file of 2.5MB. > If you can confirm your ARRL address is ok for attachments of that size > I'll email it to you direct. > > regards > > Nigel > GM8PZR > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From tvb at LeapSecond.com Sat Jun 27 15:07:22 2009 From: tvb at LeapSecond.com (Tom Van Baak) Date: Sat, 27 Jun 2009 08:07:22 -0700 Subject: [time-nuts] Orbiting crystals References: Message-ID: <141F3489BABE418BA09DCBBB5589B057@pc52> Hi Antonio, A couple of thoughts... First, remember the quartz crystals on the GPS SV are not free-running; they are just the LO of Rb or Cs atomic clocks. So you can partly answer the question yourself with a simple experiment at home. Have you ever seen frequency jumps in any of your cheap Rb or Cs clocks at home? Even one? If so how big was the jump? Second, can you better define what you mean by "frequency jump"? This is a familiar but vague term. In some respects one can say that every crystal, that every oscillator has frequency jumps. The frequency averaged over one tau is always different than than the frequency over the next tau, and the next, etc. If not, the ADEV would be zero. But as you know ADEV is never zero. The purpose of clock statistics is to show how close to zero it is. So it would be good for you to define your threshold of "jump" before we talk too much more about detecting them. /tvb From david at endor.com Sat Jun 27 15:35:36 2009 From: david at endor.com (David McGaw) Date: Sat, 27 Jun 2009 15:35:36 -0000 Subject: [time-nuts] Hand Held GPS In-Reply-To: <49DA3683.80604@greenrover.demon.co.uk> References: <49CC93C9.4010908@greenrover.demon.co.uk> <1197.SVVXXVxVQkI=.1238164282.squirrel@webmail.securepacific.net> <36802.80.251.207.129.1238271578.squirrel@webmail.lysator.liu.se> <49D0642E.3010904@greenrover.demon.co.uk> <49DA3683.80604@greenrover.demon.co.uk> Message-ID: <200906271535.n5RFZ0F1001906@mailhub2.dartmouth.edu> As I found, do be aware that the Synergy VIC-100 (58532A clone) does not like 3V. Does anyone know if the 58532A fairs better? However, my experience is that the Synergy Timing 3000 is better, even though it is also rated for 5V only. I happen to have just bought a Garmin GPSmap 60CSx myself. It is nice that it spits out NMEA-0183, though the serial string is not timed well to the internal 1PPS - delayed and jittery. :-( Thanks, David At 01:06 PM 4/6/2009, you wrote: >paul at greenrover.demon.co.uk wrote: > > >To follow up on my previous request for help, I ordered a Garmin >GPSmap60 which delivers an unloaded 3.2V to the MCX connector with fresh >batteries. > >Tried it on a couple of Symetricom and Motorola site antennas on the end >of 100 feet of cable and it works just fine. > >So thanks for all the pointers and help - job done! > >Regards Paul > >-- >73 de Paul GW8IZR IO73TI >http://www.gw8izr.com > > >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. From magnus at rubidium.dyndns.org Sat Jun 27 16:44:44 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 27 Jun 2009 18:44:44 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: <141F3489BABE418BA09DCBBB5589B057@pc52> References: <141F3489BABE418BA09DCBBB5589B057@pc52> Message-ID: <4A464C7C.3040006@rubidium.dyndns.org> Tom and Antonio, Tom Van Baak skrev: > Hi Antonio, > > A couple of thoughts... > > First, remember the quartz crystals on the GPS SV are not > free-running; they are just the LO of Rb or Cs atomic clocks. In the Block II series, the crystal oscillator responsible for transmitter circuit is a separate oscillator from any of the atomic references and their respective fly-wheel oscillator. That is how SA noise is introduced, into the loop of the transmitter oscillator. > So you can partly answer the question yourself with a simple > experiment at home. Have you ever seen frequency jumps in > any of your cheap Rb or Cs clocks at home? Even one? If so > how big was the jump? It takes a good reference to find it. The quality of oscillators have reduced the rate of jumps. > Second, can you better define what you mean by "frequency > jump"? This is a familiar but vague term. In some respects one > can say that every crystal, that every oscillator has frequency > jumps. I think looking at this reference could aid, as it covers many of the other terms, so "frequency jump" becomes distinct from that of 1/f variants of noise sources. http://www.ieee-uffc.org/frequency_control/teaching/pdf/fcdevices.pdf In general, the UFFC educational material at: http://www.ieee-uffc.org/frequency_control/teaching.asp can be a good start. For aging, have a look at this survey: http://www.ieee-uffc.org/frequency_control/teaching.asp?name=aging However, the FCS 1991 PDF is better formated variant, but password protected on the UFFC site. However, the more I read about aging effects, the less clear connection I see between material effects and frequency jumps. > The frequency averaged over one tau is always different than > than the frequency over the next tau, and the next, etc. If not, > the ADEV would be zero. But as you know ADEV is never > zero. The purpose of clock statistics is to show how close to > zero it is. So it would be good for you to define your threshold > of "jump" before we talk too much more about detecting them. A jump should be considered that or those frequency samples which significantly deviates from what the various noise sources would allow for. Random walk noise produces frequency jump like features, but through propper ADEV and MDEV analysis the levels of various 1/f noises can be established and random walk deviations can be limited. So, those level shifts which is significantly higher than expected from these noise sources is "true" frequency jumps. However, there are several systematic effects which can produce a frequency jump observation, which includes environmental effects. Let's assume that environmental effects is maintained within limits for a crystal.... Then, crystal physics and mecanics, alongside with that of the electronics comes into play. However, it is from these sources we see much of the noise we already said we elimintated. Cheers, Magnus From hmurray at megapathdsl.net Sat Jun 27 23:22:51 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Sat, 27 Jun 2009 16:22:51 -0700 Subject: [time-nuts] OCXO startup transient Message-ID: <20090627232252.731B1BCEF@ip-64-139-1-69.sjc.megapath.net> A couple of graphs in case anybody is looking for examples... This is a 3 MHz OCXO from Telco surplus. The can says EROS-800-M45, 94-12. I haven't found a data sheet but it's supposed to be equivalent to Isotemp 127-10. It's got a mechanical adjustment, no electrical adjustment. (I haven't touched the adjustment.) The can is 2.5 x 2.75 x 1.75 inches. I'd call it medium quality. Nothing fancy, but probably better than most of the small ovens. When I was playing a while ago, I could see changes when I grabbed the can with my fingers. It was powered off for at least 6 months before I started this run. I'm collecting samples every 5 minutes. I discarded the first 3 samples after power on. The first was way low. (It's so far off that the rest of any graph gets compressed into a flat line.) The next two overshot. When I run out of other things to do, I'll make another run with samples closer together for the first few hours. But first I want to watch the drift some more. So far, the drift has generally been in one direction. That's when averaged over several days. There is enough noise on the hour scale that I wouldn't want to try to predict anything to get better holdover. To my eye, there is a bend in the drift curve at 4 days. I can't think of any environmental change that happened then. I might have bumped it. For my purposes, it takes a few hours to a few days to settle down, depending upon how stable you want it. Watch for scale changes. First 3 hours: http://www.megapathdsl.net/~hmurray/time-nuts/Drift-ocxo3mhz-a.gif First 3 days: http://www.megapathdsl.net/~hmurray/time-nuts/Drift-ocxo3mhz-b.gif First 10 days: http://www.megapathdsl.net/~hmurray/time-nuts/Drift-ocxo3mhz-c.gif Days 2-12 http://www.megapathdsl.net/~hmurray/time-nuts/Drift-ocxo3mhz-d.gif -- These are my opinions, not necessarily my employer's. I hate spam. From rchensley at gmail.com Sun Jun 28 00:46:39 2009 From: rchensley at gmail.com (Ron Hensley) Date: Sat, 27 Jun 2009 17:46:39 -0700 Subject: [time-nuts] Z3801A Schematic In-Reply-To: References: Message-ID: <326e15be0906271746u795a5ac0g5d7e1c5f4be633e9@mail.gmail.com> Hi Nigel.. Just read your response to Paul inquiry. I to have been looking for info on the Z3801 box. Would you please forwarding a copy of you data to me. I picked up a Rubidium oscillator (WP-92066-l5) from Dayton in May and can't find any info on it ether. I circuit traced the interface bard within the inter housing. I'll make it available to any body who wants a copy (PDF or DXF format. Thanks Ron Hensley WB6RNH RCHENSLEY@ GMAIL (I don't know of any limit on file transfer on Google) On 6/27/09, GandalfG8 at aol.com wrote: > > In a message dated 27/06/2009 14:16:27 GMT Daylight Time, w9ac at arrl.net > writes: > > Looking for a schematic of the Z3801? I'm primarily interested in the > power > supply section. Anyone know an on-line source? I've been looking with no > success. Tnx! > ---------------- > > > Hi Paul > > There don't seem to have been any "official" schematics issued for the > Z3801A but there was a user traced schematic for the PSU posted online some > time ago. > I've just checked the URL and it's no longer valid but I have the files > archived, web page, schematics, and component notes, and have zipped them > into > a single file of 2.5MB. > If you can confirm your ARRL address is ok for attachments of that size > I'll email it to you direct. > > regards > > Nigel > GM8PZR > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Ron Hensley 408-857-2261 408-248-1382 RCHENSLEY at GMAIL.COM From Charlie.Myers at ps.net Sun Jun 28 02:10:38 2009 From: Charlie.Myers at ps.net (Myers, Charlie) Date: Sat, 27 Jun 2009 21:10:38 -0500 Subject: [time-nuts] time-nuts Digest, Vol 59, Issue 89 In-Reply-To: References: Message-ID: -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of time-nuts-request at febo.com Sent: Saturday, June 27, 2009 7:46 PM To: time-nuts at febo.com Subject: time-nuts Digest, Vol 59, Issue 89 Send time-nuts mailing list submissions to time-nuts at febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-request at febo.com You can reach the person managing the list at time-nuts-owner at febo.com When replying, please edit your Subject line so it is more specific than "Re: Contents of time-nuts digest..." From Charlie.Myers at ps.net Sun Jun 28 02:13:41 2009 From: Charlie.Myers at ps.net (Myers, Charlie) Date: Sat, 27 Jun 2009 21:13:41 -0500 Subject: [time-nuts] Z3801A Schematic In-Reply-To: References: Message-ID: Paul, The URL where all that information is posted is still on-line. The URL is http://www.realhamradio.com/GPS_Frequency_Standard.htm Enjoy the wealth of knowledge that is out there on K8CU's web site. Charlie WA3RAD -----Original Message----- From: GandalfG8 at aol.com [mailto:GandalfG8 at aol.com] Sent: Saturday, June 27, 2009 10:54 AM To: time-nuts at febo.com Subject: Re: [time-nuts] Z3801A Schematic In a message dated 27/06/2009 14:16:27 GMT Daylight Time, w9ac at arrl.net writes: Looking for a schematic of the Z3801? I'm primarily interested in the power supply section. Anyone know an on-line source? I've been looking with no success. Tnx! ---------------- Hi Paul There don't seem to have been any "official" schematics issued for the Z3801A but there was a user traced schematic for the PSU posted online some time ago. I've just checked the URL and it's no longer valid but I have the files archived, web page, schematics, and component notes, and have zipped them into a single file of 2.5MB. If you can confirm your ARRL address is ok for attachments of that size I'll email it to you direct. regards Nigel GM8PZR From GandalfG8 at aol.com Sun Jun 28 08:39:30 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sun, 28 Jun 2009 04:39:30 EDT Subject: [time-nuts] Z3801A Schematic Message-ID: In a message dated 28/06/2009 03:14:54 GMT Daylight Time, Charlie.Myers at ps.net writes: The URL where all that information is posted is still on-line. The URL is http://www.realhamradio.com/GPS_Frequency_Standard.htm Enjoy the wealth of knowledge that is out there on K8CU's web site. --------------------- Hi Charlie Realhamradio is a great source of information on the Z3801A and I checked there before posting my original reply but couldn't find anything, this is the schematic for the internal PSU of the Z3801A not an external one to drive it. I take no credit for the work, I found it online some time ago when searching for a spare DC-DC convertor for one of my units but the URL I have recorded is no longer active. It may still be online somewhere but a Google search didn't find it. regards Nigel GM8PZR From don.key at ntlworld.com Sun Jun 28 08:48:25 2009 From: don.key at ntlworld.com (Don Key) Date: Sun, 28 Jun 2009 09:48:25 +0100 Subject: [time-nuts] GPS-based frequency reference in "Everyday Practical Electronics" Message-ID: <20F8AA64842C4F0D8F2A9AE3E9347C18@JimPC> Was just catching up on my past issues of "Everyday Practical Electronics" when I noticed that the April & May 2009 issues featured a constructional article for a GPS-based frequency reference. It is based on the Garmin "GPS 15L" module, and the unit provides a 10MHz, 1MHz & 1pps output. It has an LCD display to show time, date, position, number of satellites etc. Back issues are available here:- http://www.epemag3.com/index.php?option=com_virtuemart&page=shop.browse&category_id=48&Itemid=26 From iovane at inwind.it Sun Jun 28 09:59:24 2009 From: iovane at inwind.it (iovane at inwind.it) Date: Sun, 28 Jun 2009 11:59:24 +0200 Subject: [time-nuts] Orbiting crystals Message-ID: Thanks all. Let's explain why I would like to look at orbiting crystals. In brief, along with some friends of mine, I am carrying some experimental work in the field of gravitational anomalies, and tests with vibrating matter are part of this work. This field of research has a background also in the work of others with atomic clocks. As an example, the Chinese Professor S.W.Zhou believed that at least one of his cesium clocks changed its rate in the path of a solar eclipse. See http://home.t01.itscom.net/allais/blackprior/zhou/zhou-1.pdf Look simply at the graphs. Zhou believed that cesium itself changed its rate, and instead I believe that the cesium- steered crystal "jumped". The plots actually would suggest jumps. Yes, crystal jumps are rare events. By "jump" I mean what has been well described by Magnus. I had never observed one at home, but clear examples may be often seen on the online GPSDO in Colima, Mexico. Making experiments during eclipses would almost always mean that a measuring instrument should be put in the eclipse path. This is not always possible, or at least it is quite expensive. So, I thought to take advantage of remote crystals that could transmit data about themselves while crossing eclipses. As far as I can understand, crystal jumps may not be due only to strain release, but also to rapid migration from one to another metastable state and vice-versa. I'm wondering if this could also occur in the presence of special gravitational circumstances such as during eclipses. We have clues (and even more the prior art has) that eclipses are special from the gravitational point of view (something strange and unpredictable does occur, looks like the forces do not play as expected) but we have not yet devised the ultimate undisputable test. We are still collecting clues, and the behavior of crystals in the eclipse path could give its contribution. Maybe the probability to get a significant result is not worth the effort of setting up, but I would like to explore this. Thanks for the tips and for cautioning me against the possible problems. Anyway I take from this brief discussion that there might be some possibility. I will meditate about. Bye, Antonio I8IOV From GandalfG8 at aol.com Sun Jun 28 10:30:16 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sun, 28 Jun 2009 06:30:16 EDT Subject: [time-nuts] Z3801A PSU and Outer Oven Control Message-ID: Hi All Following my earlier post re the Z3801A PSU schematic I've realised that the information I've emailed to several list members is not complete. As well as the internal PSU description and schematic the original web site also hosted a description and schematic for the outer oven controller, which is part of the PSU circuit board, but I had this filed separately. I have now combined all the relevant files into a single zip file, which should maintain the directory structure on extraction, and would recommend downloading this as a replacement for the earlier files. This way too it's all kept together and the originator will get proper credit for his work. The file is at..... _http://rapidshare.com/files/249531410/Z3801APSUandOven.zip_ (http://rapidshare.com/files/249531410/Z3801APSUandOven.zip) I've had some problems uploading to Didier's site from the flaky broadband connection here but If Didier, or anybody else for that matter, would like to upload it there that's fine with me. As said earlier, I take no credit for this, I'm just the messenger:-), but please note I take no responsibility either if there's any errors. regards Nigel GM8PZR From magnus at rubidium.dyndns.org Sun Jun 28 11:19:30 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 28 Jun 2009 13:19:30 +0200 Subject: [time-nuts] OCXO startup transient In-Reply-To: <20090627232252.731B1BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090627232252.731B1BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A4751C2.9030104@rubidium.dyndns.org> Hal Murray wrote: > A couple of graphs in case anybody is looking for examples... > > This is a 3 MHz OCXO from Telco surplus. > > The can says EROS-800-M45, 94-12. I haven't found a data sheet but it's > supposed to be equivalent to Isotemp 127-10. > > It's got a mechanical adjustment, no electrical adjustment. (I haven't > touched the adjustment.) > > The can is 2.5 x 2.75 x 1.75 inches. I'd call it medium quality. Nothing > fancy, but probably better than most of the small ovens. When I was playing > a while ago, I could see changes when I grabbed the can with my fingers. > > It was powered off for at least 6 months before I started this run. > > > I'm collecting samples every 5 minutes. I discarded the first 3 samples > after power on. The first was way low. (It's so far off that the rest of > any graph gets compressed into a flat line.) The next two overshot. > > When I run out of other things to do, I'll make another run with samples > closer together for the first few hours. But first I want to watch the drift > some more. > > So far, the drift has generally been in one direction. That's when averaged > over several days. There is enough noise on the hour scale that I wouldn't > want to try to predict anything to get better holdover. Your holdover properties should be evaluated after running for say 30 days. A frequency compensation get you a first degree correction which together with TDEV measures give you an indication of aggregated holdover properties. > To my eye, there is a bend in the drift curve at 4 days. I can't think of > any environmental change that happened then. I might have bumped it. Considering the wobble on day 8, I'd say the day 4 shift is within what environmental shifts do to you, where as on day 4 the curvature is still steep so the added effects fools the eye. Cheers, Magnus From paul at greenrover.demon.co.uk Sun Jun 28 11:31:36 2009 From: paul at greenrover.demon.co.uk (paul at greenrover.demon.co.uk) Date: Sun, 28 Jun 2009 12:31:36 +0100 Subject: [time-nuts] Hand Held GPS In-Reply-To: <200906271535.n5RFZ0F1001906@mailhub2.dartmouth.edu> References: <49CC93C9.4010908@greenrover.demon.co.uk> <1197.SVVXXVxVQkI=.1238164282.squirrel@webmail.securepacific.net> <36802.80.251.207.129.1238271578.squirrel@webmail.lysator.liu.se> <49D0642E.3010904@greenrover.demon.co.uk> <49DA3683.80604@greenrover.demon.co.uk> <200906271535.n5RFZ0F1001906@mailhub2.dartmouth.edu> Message-ID: <4A475498.8010402@greenrover.demon.co.uk> David McGaw wrote: > As I found, do be aware that the Synergy VIC-100 (58532A clone) does not > like 3V. Does anyone know if the 58532A fairs better? However, my > experience is that the Synergy Timing 3000 is better, even though it is > also rated for 5V only. > > I happen to have just bought a Garmin GPSmap 60CSx myself. It is nice > that it spits out NMEA-0183, though the serial string is not timed well > to the internal 1PPS - delayed and jittery. :-( > Hi David What happened here is that the mcx connector and lead worked ok. But much out of boredom than anything else I also made an adapter with a tail cable to a small box and put a 5v current limited reg in it. Pick up the BTS 24v dc from the site and then used it that way. On the site antennas that we use 3V seems to do the trick but the dc insertion of 5v makes sure. There are far better people on this list to advise on the jitter - not me ..... but out of curiosity is the jitter on the usb connection or the rs232 connection, I *thought* I read somewhere that the USB isn't the best way to do it? Regards Paul -- 73 de Paul GW8IZR IO73TI http://www.gw8izr.com From kyrrin at bluefeathertech.com Sun Jun 28 12:59:14 2009 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Sun, 28 Jun 2009 05:59:14 -0700 Subject: [time-nuts] GPS-based frequency reference in "Everyday Practical Electronics" In-Reply-To: <20F8AA64842C4F0D8F2A9AE3E9347C18@JimPC> References: <20F8AA64842C4F0D8F2A9AE3E9347C18@JimPC> Message-ID: <200906280559140859.0B799194@192.168.42.129> Good catch, thanks! I just ordered both back issues. That'll give me something to do with the 15L module I have stashed in my bench drawer. One question: I placed the order, and completed the checkout process, but have not yet been able to download the issues. As near as I can tell, the publishers actually E-mail you a download link once they finish processing on their end, yes? If that's the case, I'm guessing I won't see the download code until, say, Monday? Happy timing. *********** REPLY SEPARATOR *********** On 28-Jun-09 at 09:48 Don Key wrote: >Was just catching up on my past issues of "Everyday Practical >Electronics" when I noticed that the April & May 2009 issues featured a >constructional article for a GPS-based frequency reference. > >It is based on the Garmin "GPS 15L" module, and the unit provides a 10MHz, >1MHz & 1pps output. It has an LCD display to show time, date, position, >number of satellites etc. > >Back issues are available here:- >http://www.epemag3.com/index.php?option=com_virtuemart&page=shop.browse&category_id=48&Itemid=26 >_______________________________________________ >time-nuts mailing list -- time-nuts at febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > >__________ Information from ESET Smart Security, version of virus >signature database 4193 (20090626) __________ > >The message was checked by ESET Smart Security. > >http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "Quid Malmborg in Plano..." From clintonjeffrey1 at bigpond.com Sun Jun 28 13:07:54 2009 From: clintonjeffrey1 at bigpond.com (Clint Jeffrey) Date: Sun, 28 Jun 2009 23:07:54 +1000 Subject: [time-nuts] GPS-based frequency reference in "Everyday Practical Electronics" In-Reply-To: <200906280559140859.0B799194@192.168.42.129> References: <20F8AA64842C4F0D8F2A9AE3E9347C18@JimPC> <200906280559140859.0B799194@192.168.42.129> Message-ID: Hi Folks, Same here, I've just completed the ordering process which also meant signing up to a Google Check out thing...oh well...anyway I'm also waiting for the next phase so I can download the articles... Cheers Clint - VK3CSJ Melbourne... Good catch, thanks! I just ordered both back issues. That'll give me something to do with the 15L module I have stashed in my bench drawer. One question: I placed the order, and completed the checkout process, but have not yet been able to download the issues. As near as I can tell, the publishers actually E-mail you a download link once they finish processing on their end, yes? If that's the case, I'm guessing I won't see the download code until, say, Monday? Happy timing. On 28-Jun-09 at 09:48 Don Key wrote: Was just catching up on my past issues of "Everyday Practical Electronics" when I noticed that the April & May 2009 issues featured a constructional article for a GPS-based frequency reference. It is based on the Garmin "GPS 15L" module, and the unit provides a 10MHz, 1MHz & 1pps output. It has an LCD display to show time, date, position, number of satellites etc. Back issues are available here:- http://www.epemag3.com/index.php?option=com_virtuemart&page=shop.browse&category_id=48&Itemid=26 From TimeNut at austin.rr.com Sun Jun 28 15:21:48 2009 From: TimeNut at austin.rr.com (Graham / KE9H) Date: Sun, 28 Jun 2009 10:21:48 -0500 Subject: [time-nuts] GPS-based frequency reference in "Everyday Practical Electronics" In-Reply-To: <200906280559140859.0B799194@192.168.42.129> References: <20F8AA64842C4F0D8F2A9AE3E9347C18@JimPC> <200906280559140859.0B799194@192.168.42.129> Message-ID: <4A478A8C.1080102@austin.rr.com> Be sure to read what the article says the systems delivers for output stability before you decide to build it. It disciplines an inexpensive TCXO (not OCXO) with very short averaging times, with a GPS navigation receiver, not a timing receiver. It is good enough to set the time base in your HF rig to a fraction of a Hertz, but not much more accurate than that. --- Graham / KE9H == Bruce Lane wrote: > Good catch, thanks! I just ordered both back issues. That'll give me something to do with the 15L module I have stashed in my bench drawer. > > One question: I placed the order, and completed the checkout process, but have not yet been able to download the issues. As near as I can tell, the publishers actually E-mail you a download link once they finish processing on their end, yes? If that's the case, I'm guessing I won't see the download code until, say, Monday? > > Happy timing. > > *********** REPLY SEPARATOR *********** > > On 28-Jun-09 at 09:48 Don Key wrote: > > >> Was just catching up on my past issues of "Everyday Practical >> Electronics" when I noticed that the April & May 2009 issues featured a >> constructional article for a GPS-based frequency reference. >> >> It is based on the Garmin "GPS 15L" module, and the unit provides a 10MHz, >> 1MHz & 1pps output. It has an LCD display to show time, date, position, >> number of satellites etc. >> >> Back issues are available here:- >> http://www.epemag3.com/index.php?option=com_virtuemart&page=shop.browse&category_id=48&Itemid=2 >> From magnus at rubidium.dyndns.org Sun Jun 28 15:30:41 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sun, 28 Jun 2009 17:30:41 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: Message-ID: <4A478CA1.20900@rubidium.dyndns.org> iovane at inwind.it skrev: > Thanks all. > > Let's explain why I would like to look at orbiting crystals. > In brief, along with some friends of mine, I am carrying some > experimental work in the field of gravitational anomalies, and > tests with vibrating matter are part of this work. > This field of research has a background also in the work of > others with atomic clocks. As an example, the Chinese > Professor S.W.Zhou believed that at least one of his cesium > clocks changed its rate in the path of a solar eclipse. See > > http://home.t01.itscom.net/allais/blackprior/zhou/zhou-1.pdf > > Look simply at the graphs. Zhou believed that cesium itself > changed its rate, and instead I believe that the cesium- > steered crystal "jumped". The plots actually would suggest > jumps. > > Yes, crystal jumps are rare events. By "jump" I mean what has > been well described by Magnus. I had never observed one at > home, but clear examples may be often seen on the online GPSDO > in Colima, Mexico. > > Making experiments during eclipses would almost always mean > that a measuring instrument should be put in the eclipse path. > This is not always possible, or at least it is quite > expensive. So, I thought to take advantage of remote crystals > that could transmit data about themselves while crossing > eclipses. > > As far as I can understand, crystal jumps may not be due only > to strain release, but also to rapid migration from one to > another metastable state and vice-versa. I'm wondering if this > could also occur in the presence of special gravitational > circumstances such as during eclipses. We have clues (and even > more the prior art has) that eclipses are special from the > gravitational point of view (something strange and > unpredictable does occur, looks like the forces do not play as > expected) but we have not yet devised the ultimate > undisputable test. We are still collecting clues, and the > behavior of crystals in the eclipse path could give its > contribution. Do read the article I referred to on aging. I think that any gravitational issues during the eclipse event is far less than the effect of sudden cooling, loss of sunlight. Does the ionspheric TEC change drastically? You need a good L1/L2 GPS receiver for that. What is the means of comparision? 100 kHz radio transmissions? GPS? What medium was used? Can any eclipse effects be seen in that medium? Multiple phase comparision methods is needed to rinse out the effects of them from that of the clocks themselves. Expect everything to change and figure out ways to measure that to clear out what was affected and not. For freak-events like this, everyone has their favorite root cause. > Maybe the probability to get a significant result is not worth > the effort of setting up, but I would like to explore this. > > Thanks for the tips and for cautioning me against the possible > problems. Anyway I take from this brief discussion that there > might be some possibility. I will meditate about. Cheers, Magnus From james.p.lux at jpl.nasa.gov Sun Jun 28 15:33:31 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 28 Jun 2009 08:33:31 -0700 Subject: [time-nuts] Orbiting crystals In-Reply-To: Message-ID: On 6/28/09 2:59 AM, "iovane at inwind.it" wrote: > Thanks all. > > Let's explain why I would like to look at orbiting crystals. > > Making experiments during eclipses would almost always mean > that a measuring instrument should be put in the eclipse path. > This is not always possible, or at least it is quite > expensive. So, I thought to take advantage of remote crystals > that could transmit data about themselves while crossing > eclipses. Ah.. That's easy.. Pretty much every satellite in orbit derives its transmit frequency from a crystal oscillator, either a TCXO or a OCXO. So all you have to do is pick a LEO satellite that is easy to receive and measure the transmitted frequency, and that is at a frequency where other effects won't dominate (ionospheric uncertainties, for instance, probably rule out VHF and UHF downlinks). For instance, QuikScat (which I helped build, so I'm real familiar with it) has a radar that radiates about 100W through a 40dBi antenna at 13.402 GHz, derived from an approximately 28 MHz crystal. It's a huge signal on the ground, detectable with an open waveguide pointed roughly in the right direction into a LNA and spectrum analyzer. It's probably not what you want (it's chirped and pulsed), but I'm sure there's other satellites around that would work. In my work (and that of some folks at BYU) we looked at the received QuikScat signals to try and characterize things like the oscillator performance, and a back of the envelope analysis showed that you can just barely detect relativistic effects, after removing all the other known effects (the chirping, the doppler, etc.). Look for papers at the 2000 IGARSS conference. I'd look for something like Iridium or Globalstar and see if there's a convenient pilot signal that's easily detectable. From rexa at sonic.net Sun Jun 28 18:53:14 2009 From: rexa at sonic.net (Rex) Date: Sun, 28 Jun 2009 11:53:14 -0700 Subject: [time-nuts] Z3801A PSU and Outer Oven Control In-Reply-To: References: Message-ID: <4A47BC1A.1080900@sonic.net> GandalfG8 at aol.com wrote: >Hi All > > >I've had some problems uploading to Didier's site from the flaky broadband >connection here but If Didier, or anybody else for that matter, would like >to upload it there that's fine with me. > >regards > >Nigel >GM8PZR > > > > No need to upload. You should have looked first. Both information repositories are already there. http://www.ko4bb.com/cgi-bin/manuals.pl?dir=05)_GPS_Timing/Z3801 I thought this is the kind of thing Didier might have already collected. From brad at braddye.com Sun Jun 28 19:33:14 2009 From: brad at braddye.com (Brad Dye) Date: Sun, 28 Jun 2009 14:33:14 -0500 Subject: [time-nuts] GPSDO project Message-ID: I have just purchased a Thunderbolt GPS receiver. I hope to use this to discipline an oscillator on 66.66666 MHz so I can use it as a LO on my Software Defined Receiver (SDR-IQ). Building such an oscillator is a little over my head so I thought I would ask the group if anyone knows where I could buy the missing link of this project. I have put a drawing of my project on the web showing the specs of what I need. The oscillator is shown in the blue box. Any help or suggestions would be greatly appreciated. http://www.braddye.com/gps_do.html 73s Brad Dye K9IQY ex KN9IQY, KN4BK, KM5NK, WB4JCF, ZP5TQ, WA4VXU, WA9RVL, /TI2, /9Y4, / 6Y5, /KP4 52 years as a FCC licensed amateur radio operator 36 years as a FCC licensed first class commercial radio operator From GandalfG8 at aol.com Sun Jun 28 19:46:31 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sun, 28 Jun 2009 15:46:31 EDT Subject: [time-nuts] Z3801A PSU and Outer Oven Control Message-ID: In a message dated 28/06/2009 19:54:05 GMT Daylight Time, rexa at sonic.net writes: No need to upload. You should have looked first. Both information repositories are already there. http://www.ko4bb.com/cgi-bin/manuals.pl?dir=05)_GPS_Timing/Z3801 I thought this is the kind of thing Didier might have already collected. ---------------- And not only that, but from the identical structure I'd say it's almost 100% guaranteed that they're my files.......... Whoops:-) I did make them available once before and it's even quite possible, prior to my having problems, that I could have uploaded them myself and forgotten about it, the remaining braincell does struggle a bit with trivia these days! Oh well, I obviously wasn't the only one not aware. There's been over 30 downloads from my rapidshare link so I still consider it worth the effort. regards Nigel GM8PZR From GandalfG8 at aol.com Sun Jun 28 20:00:43 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sun, 28 Jun 2009 16:00:43 EDT Subject: [time-nuts] GPSDO project Message-ID: In a message dated 28/06/2009 20:34:25 GMT Daylight Time, brad at braddye.com writes: I have just purchased a Thunderbolt GPS receiver. I hope to use this to discipline an oscillator on 66.66666 MHz so I can use it as a LO on my Software Defined Receiver (SDR-IQ). Building such an oscillator is a little over my head so I thought I would ask the group if anyone knows where I could buy the missing link of this project. I have put a drawing of my project on the web showing the specs of what I need. The oscillator is shown in the blue box. Any help or suggestions would be greatly appreciated. http://www.braddye.com/gps_do.html --------------- One option, although perhaps a bit bulky as it's a 3U 19inch rackmount unit, would be to use something like a PTS160 synthesiser, or Wavetek 5120A which is similar, which can be driven by an external 10MHz reference and can provide outputs between 100KHz and 160MHz with resolution as fine as 0.1Hz depending on number of incremental modules fitted. regards Nigel GM8PZR From cdelect at juno.com Sun Jun 28 20:25:26 2009 From: cdelect at juno.com (Corby Dawson) Date: Sun, 28 Jun 2009 13:25:26 -0700 Subject: [time-nuts] Z3801A outer oven Message-ID: <20090628.132526.3152.2.cdelect@juno.com> Hi, Has anyone measured the outer oven temp of the double oven HP oscillator in the Z3801A? Thanks, Corby Dawson ____________________________________________________________ Criminal Lawyers - Click here. http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTOVoJJqbtOo6enTfaz0fMV04CWAyF1IU5BroLe9NIRqwY67nchKVq/ From stanw1le at verizon.net Sun Jun 28 21:20:49 2009 From: stanw1le at verizon.net (Stan W1LE) Date: Sun, 28 Jun 2009 17:20:49 -0400 Subject: [time-nuts] GPSDO project In-Reply-To: References: Message-ID: <4A47DEB1.2000406@verizon.net> Additional suggestions, for short term realization, and cost effective: PTS synthesizer that will cover the desired freq, Programmed Test Sources are common on Ebay. Can use an external 10 MHz reference. Get one with front panel knobs (setability). Possibly a FLUKE model 6061B synthesizer, tunable in 1 Hz steps. Can use a 5 MHz reference Useable to 160 MHz. Other synthesizers from commercial test equipment manufacturers. Stan, W1LE Brad Dye wrote: > I have just purchased a Thunderbolt GPS receiver. I hope to use this > to discipline an oscillator on 66.66666 MHz so I can use it as a LO on > my Software Defined Receiver (SDR-IQ). From hmurray at megapathdsl.net Sun Jun 28 21:38:28 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Sun, 28 Jun 2009 14:38:28 -0700 Subject: [time-nuts] GPSDO project In-Reply-To: Message from Brad Dye of "Sun, 28 Jun 2009 14:33:14 CDT." Message-ID: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> You want 66.6666 MHz from 10 MHz. I can think of several approaches. 1) Patch the radio stuff to work with 10 MHz. Since 10 MHz is common from things like GPSDOs or Telco surplus rubidium clocks, somebody may have done that already. 2) Build a PLL. The first step is probably to find a 66.666 MHz oscillator that has an external fine tuning pin. Then it's divide by 20 and 3, compare, filter... 3) Get to 66.666 MHz by dividing by 3 then multiplying by 2 and 5. I don't know much about this area, but there was a lot of discussion here a few months ago. Check the archives. 4) Use a DDS chip to synthesize 66.666 MHz. Analog Devices makes lots of nice ones. One problem with DDSes is that they normally make spurs. But they aren't a problem if the target frequency is a clean multiple of the source frequency. 20/3 doesn't sound clean, but I'd have to do a lot of work to check the details. There may be a clean frequency that is close enough to 66.666 MHz and/or one that has spurs that are far enough out so you can filter them. 5) Use a low cost 66.666 MHz oscillator and live with the error. You may be able to correct any errors. The key step would be to feed the 66.666 MHz to a counter running off the T-Bolt clock so you know the real frequency of your 66.666 MHz osc. Suppose your 66.666 MHz is 73 ppm fast and you want to listen to 12.123 MHz. You would set the radio to listen to 73 PPM below 12.123 MHz. -- These are my opinions, not necessarily my employer's. I hate spam. From iovane at inwind.it Sun Jun 28 21:57:03 2009 From: iovane at inwind.it (iovane at inwind.it) Date: Sun, 28 Jun 2009 23:57:03 +0200 Subject: [time-nuts] Orbiting crystals Message-ID: Magnus Danielson wrote: > Do read the article I referred to on aging. I think that any > gravitational issues during the eclipse event is far less than the > effect of sudden cooling, loss of sunlight. Does the ionspheric TEC > change drastically? You need a good L1/L2 GPS receiver for that. > What is the means of comparision? 100 kHz radio transmissions? GPS? What > medium was used? Can any eclipse effects be seen in that medium? > Multiple phase comparision methods is needed to rinse out the effects of > them from that of the clocks themselves. Expect everything to change and > figure out ways to measure that to clear out what was affected and not. > > For freak-events like this, everyone has their favorite root cause. > We are aware that there are hidden traps, and we try to diversify and cross-correlare experiments of different nature. The progress is very slow because eclipses are rare events at any given location, but they occur twice a year on the planet, and I just thought to take advantage of satellites to possibly speed-up the work. I don't believe the idea is completely new. What is new, I think, is looking for sudden jumps, which may have been filtered out by other workers. The thermal shock at crossing the shadow is a severe issue, but some instruments detected effects before and after the optical eclipse and on the anti-eclipse path (the other side of the planet). There is a non-official position of NASA on this, read MSG#26 at http://xoomer.virgilio.it/iovane/mails.htm (....We have a number of anomalies recorded on different....). Not sure my idea is good, but what to do waiting for the next eclipse here? Should it be within my reach, I would be pleased to try looking at sats. Or, maybe, time-nuts who happen to be in the eclipse path in the future with their cesium clocks, could help. Or, further, time-nuts may have suggestions such as I'm getting from you. In the future, in case, I will ask you what you mean by "good" L1/l2 receiver. (I apologize for for some OT content) Cheers, Antonio I8IOV From bruce.griffiths at xtra.co.nz Sun Jun 28 22:04:49 2009 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Mon, 29 Jun 2009 10:04:49 +1200 Subject: [time-nuts] GPSDO project In-Reply-To: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> References: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> Message-ID: <4A47E901.5000309@xtra.co.nz> Hal Murray wrote: > You want 66.6666 MHz from 10 MHz. > > I can think of several approaches. > > 1) Patch the radio stuff to work with 10 MHz. Since 10 MHz is common from > things like GPSDOs or Telco surplus rubidium clocks, somebody may have done > that already. > > 2) Build a PLL. The first step is probably to find a 66.666 MHz oscillator > that has an external fine tuning pin. Then it's divide by 20 and 3, compare, > filter... > > 3) Get to 66.666 MHz by dividing by 3 then multiplying by 2 and 5. I don't > know much about this area, but there was a lot of discussion here a few > months ago. Check the archives. > Actually need to multiply 3.333.. MHz by 20 (5 x 2 x 2) No need to multiply by 2 or 4, if the output of the divide by 3 is a 1/3 duty cycle square wave, one can extract the 2nd (or 4th) harmonic of the square wave repetition rate with a filter. Amplify and multiply by 5 (can use the same approach as used in the 5370A/B frequency multiplier chain (1 transistor per multiplier) and filter. A high level injection locked divider can have lower close in phase noise than a digital one. > 4) Use a DDS chip to synthesize 66.666 MHz. Analog Devices makes lots of > nice ones. One problem with DDSes is that they normally make spurs. But > they aren't a problem if the target frequency is a clean multiple of the > source frequency. 20/3 doesn't sound clean, but I'd have to do a lot of work > to check the details. There may be a clean frequency that is close enough to > 66.666 MHz and/or one that has spurs that are far enough out so you can > filter them. > > 5) Use a low cost 66.666 MHz oscillator and live with the error. You may be > able to correct any errors. The key step would be to feed the 66.666 MHz to > a counter running off the T-Bolt clock so you know the real frequency of your > 66.666 MHz osc. Suppose your 66.666 MHz is 73 ppm fast and you want to > listen to 12.123 MHz. You would set the radio to listen to 73 PPM below > 12.123 MHz. > > > > Bruce From g4hup at btinternet.com Sun Jun 28 22:15:44 2009 From: g4hup at btinternet.com (dave powis) Date: Sun, 28 Jun 2009 22:15:44 +0000 (GMT) Subject: [time-nuts] GPSDO project - 66.667MHz from 10MHz In-Reply-To: <4A47E901.5000309@xtra.co.nz> References: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> <4A47E901.5000309@xtra.co.nz> Message-ID: <690441.15168.qm@web86305.mail.ird.yahoo.com> You can also use a DFS (Direct Frequency Synthesiser) to produce 66.667MHz in two ways - either 50 + 16.667MHz, or 70 - 3.33MHz. Information on the 50+16.667 is on my web site (http://g4hup.com), and has been implemented as a reference source for an SDR-IQ receiver. Another customer of mine has also implemented the 70-3.33MHz version for the same application - I don't have the filter component values or detail design posted, but could provide them on request.. My personal preference is for the slightly more complex 50+16.667Mhz option, since the filtering is a little easier at VHF - but both solutions work, and give a good clean, stable low-noise output (depending on the quality of your 10MHz reference input, of course!) Kits are available. Hope this helps 73, Dave, G4HUP ________________________________ From: Bruce Griffiths To: Discussion of precise time and frequency measurement Sent: Sunday, 28 June, 2009 11:04:49 PM Subject: Re: [time-nuts] GPSDO project Hal Murray wrote: > You want 66.6666 MHz from 10 MHz. > > I can think of several approaches. > > 1) Patch the radio stuff to work with 10 MHz. Since 10 MHz is common from > things like GPSDOs or Telco surplus rubidium clocks, somebody may have done > that already. > > 2) Build a PLL. The first step is probably to find a 66.666 MHz oscillator > that has an external fine tuning pin. Then it's divide by 20 and 3, compare, > filter... > > 3) Get to 66.666 MHz by dividing by 3 then multiplying by 2 and 5. I don't > know much about this area, but there was a lot of discussion here a few > months ago. Check the archives. > Actually need to multiply 3.333.. MHz by 20 (5 x 2 x 2) No need to multiply by 2 or 4, if the output of the divide by 3 is a 1/3 duty cycle square wave, one can extract the 2nd (or 4th) harmonic of the square wave repetition rate with a filter. Amplify and multiply by 5 (can use the same approach as used in the 5370A/B frequency multiplier chain (1 transistor per multiplier) and filter. A high level injection locked divider can have lower close in phase noise than a digital one. > 4) Use a DDS chip to synthesize 66.666 MHz. Analog Devices makes lots of > nice ones. One problem with DDSes is that they normally make spurs. But > they aren't a problem if the target frequency is a clean multiple of the > source frequency. 20/3 doesn't sound clean, but I'd have to do a lot of work > to check the details. There may be a clean frequency that is close enough to > 66.666 MHz and/or one that has spurs that are far enough out so you can > filter them. > > 5) Use a low cost 66.666 MHz oscillator and live with the error. You may be > able to correct any errors. The key step would be to feed the 66.666 MHz to > a counter running off the T-Bolt clock so you know the real frequency of your > 66.666 MHz osc. Suppose your 66.666 MHz is 73 ppm fast and you want to > listen to 12.123 MHz. You would set the radio to listen to 73 PPM below > 12.123 MHz. > > > > Bruce _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From iovane at inwind.it Sun Jun 28 22:23:12 2009 From: iovane at inwind.it (iovane at inwind.it) Date: Mon, 29 Jun 2009 00:23:12 +0200 Subject: [time-nuts] Orbiting crystals Message-ID: James Lux wrote: > Ah.. That's easy.. Pretty much every satellite in orbit derives its transmit > frequency from a crystal oscillator, either a TCXO or a OCXO. So all you > have to do is pick a LEO satellite that is easy to receive and measure the > transmitted frequency, and that is at a frequency where other effects won't > dominate (ionospheric uncertainties, for instance, probably rule out VHF and > UHF downlinks). Hi James, that's easy for you at Nasa! You have rotary antennas, good receivers and so on... I thought to GPS sats because there are cheap receivers all around, and hoped the 1 PPS would tell something, so freeing me from considering doppler, relativity etc. Anyway, please let me know if you find any easily detectable signals that doesn't require a tracking antenna. Bye, Antonio I8IOV From wb6bnq at cox.net Sun Jun 28 22:55:46 2009 From: wb6bnq at cox.net (WB6BNQ) Date: Sun, 28 Jun 2009 15:55:46 -0700 Subject: [time-nuts] GPSDO project References: Message-ID: <4A47F4F2.CE327901@cox.net> Hi Brad, I am a little confused about your intentions. There is no mention on the RFspace web site about a provision of being able to feed in an external reference signal to the SDR-IQ or the SDR-14 for that matter. If you study the Analog devices AD6620 component, you will see that it is a 3.3 volt * * * ONLY * * * process, which only adds to the problem. Additionally there are constraints on the rise and fall times of the timing signal. This is a horrifically complex component with intricate dependencies tied to the specific A/D used. This is not your daddy's VFO from yester-year. The fact that the internal DDS is a digital function means you will never, ever, get to a perfect cardinal point, except under very special conditions. In this case it will have an offset of 16 pico-seconds because that is the smallest resolution the DDS can do. While small it would require very special hardware for you to keep it locked to the GPS. As the internal clocking system runs more then just the DDS, other considerations come into play. The "clocks" built to run these chips are not designed for external control and studying the physical layout of the SDR-IQ, it does not appear that they provided any means to have external clocking ability. Besides the computer's sound card DSP is heavily involved with regards to the "frequency" calibration. So there are two independent clocks to keep synchronized that are not related to the "listening time," particularly if you record the digital bits for later listening or analysis. Fortunately, the software will allow for you to calibrate, to some degree, but it is not and you will not be able to approach what you expect to do with the Thunderbolt. Keep in mind that the best you could do with a Thunderbolt on a 1 second per second comparison basis is only 1 part in 10 to the minus ninth (1x10^-9). It gets worse if you consider shorter times like a continuous analog aspect that you would have for active listening. The noise of the GPS system would mask the 16 pico-second resolution of the SDR-IQ DDS. The real problem is temperature. You could improve that by providing a chamber for the SDR-IQ and raising, carefully, the temperature to just above your highest ambient level. After all that, I am not saying you couldn't/wouldn't/shouldn't consider it. Keep in mind that the SDR-IQ, or for that matter, the SDR-14 DDS only sets the center of the 190 KHz bandwidth swath that you are viewing at any one time. The real fine aspect is done in the computer and the clocks in those are all over the map, so to speak. In order to have a really tight calibration, with "Timenuts" quality, would involve some serious effort to build a clocking system for both the SDR-IQ and the computer. The final result is you would still be offset due to the digital processes in both the SDR-IQ and the computer, plus, perhaps, some latency in the software. As I get to the point of sending this email I see that Dave Powis, G4HUP, has gone to the trouble to lock the SDR-IQ internal oscillator to an external 10 MHz. If you look at all the information on his web site, you will see that it is not a trivial project. As I pointed out, this only stabilizes the "window" of the SDR-IQ still leaving the computer to tend with. My experience with the Thunderbolt shows that it has some temperature dependencies and the expected nominal noise of the GPS system in the short term regard. What most people do is have a high quality "house" standard and do long term comparisons to the GPS. A high quality "house" standard would, in effect, filter the short term noise of the GPS system. At any rate, this is my fantasy and I am sticking to it ! Bill....WB6BNQ Brad Dye wrote: > I have just purchased a Thunderbolt GPS receiver. I hope to use this > to discipline an oscillator on 66.66666 MHz so I can use it as a LO on > my Software Defined Receiver (SDR-IQ). > > Building such an oscillator is a little over my head so I thought I > would ask the group if anyone knows where I could buy the missing link > of this project. I have put a drawing of my project on the web showing > the specs of what I need. The oscillator is shown in the blue box. > > Any help or suggestions would be greatly appreciated. > > http://www.braddye.com/gps_do.html > > 73s > > Brad Dye K9IQY > ex KN9IQY, KN4BK, KM5NK, WB4JCF, ZP5TQ, WA4VXU, WA9RVL, /TI2, /9Y4, / > 6Y5, /KP4 > 52 years as a FCC licensed amateur radio operator > 36 years as a FCC licensed first class commercial radio operator > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From Murray.Greenman at rakon.com Sun Jun 28 23:07:33 2009 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Mon, 29 Jun 2009 11:07:33 +1200 Subject: [time-nuts] Generating 66.666...MHz from 10MHz In-Reply-To: References: Message-ID: Here's an idea which actually works (I tried it). Rather than lock at 10MHz, you lock directly to 1pps. You can lock an XO to 1/3 Hz steps by locking to 1pps and ignoring two out of three results from the TIC. I did it at 7.333MHz, using an AT90S2313 micro, and you could just as easily do it at 8.333... and then multiply by 8. Yes, it does leave you with a very low loop frequency! Although I've not tried it, you could potentially add 120 degrees equivalent to one intermediate TIC result and subtract 120 degrees from the next, and so lock at 1Hz. 73, Murray ZL1BPU From magnus at rubidium.dyndns.org Sun Jun 28 23:30:35 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Mon, 29 Jun 2009 01:30:35 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: Message-ID: <4A47FD1B.1030303@rubidium.dyndns.org> iovane at inwind.it wrote: > Magnus Danielson wrote: > >> Do read the article I referred to on aging. I think that any >> gravitational issues during the eclipse event is far less than the >> effect of sudden cooling, loss of sunlight. Does the ionspheric TEC >> change drastically? You need a good L1/L2 GPS receiver for that. >> What is the means of comparision? 100 kHz radio transmissions? GPS? What >> medium was used? Can any eclipse effects be seen in that medium? >> Multiple phase comparision methods is needed to rinse out the effects of >> them from that of the clocks themselves. Expect everything to change and >> figure out ways to measure that to clear out what was affected and not. >> >> For freak-events like this, everyone has their favorite root cause. >> > > We are aware that there are hidden traps, and we try to > diversify and cross-correlare experiments of different nature. > The progress is very slow because eclipses are rare events at > any given location, but they occur twice a year on the planet, > and I just thought to take advantage of satellites to possibly > speed-up the work. I don't believe the idea is completely new. > What is new, I think, is looking for sudden jumps, which may > have been filtered out by other workers. The thermal shock at > crossing the shadow is a severe issue, but some instruments > detected effects before and after the optical eclipse and on > the anti-eclipse path (the other side of the planet). I think I have found just the article for you! On the 1993 FCS there was a presentation of an article titled "ANALYSIS OF THE FREQUENCY STABILITY OF ON-ORBIT GPS NAVSTAR CLOCKS". This article goes into some details as showing the thermal shock and the effect of eclipse seasons on especially the rubidium clocks onboard. If you have UFFC access, search-terms such as "space" and "orbit" should get you going, but the "orbit" seems to give you better experience rather than expectance properties. > There is > a non-official position of NASA on this, read MSG#26 at > > http://xoomer.virgilio.it/iovane/mails.htm > > (....We have a number of anomalies recorded on different....). > > Not sure my idea is good, but what to do waiting for the next > eclipse here? Should it be within my reach, I would be pleased > to try looking at sats. There are people looking after their sats, which could give you insight, maybe already published. > Or, maybe, time-nuts who happen to be in the eclipse path in > the future with their cesium clocks, could help. Or, further, > time-nuts may have suggestions such as I'm getting from you. > In the future, in case, I will ask you what you mean by "good" > L1/l2 receiver. You want a geodesic style receiver which can be hooked to an external frequency source, act as a base-station and produce RINEX data on a continous operational mode for the vissible sats (12 is an acceptable limit). An example of such a receiver is the Ashtech Z-12. A suitable phase-stable antenna is also assumed. Beware that options of a particular receiver may prohibit you from the use you intend. Oh, if you are good at math, you could predict when a particular sat is hit by moon shadow and when it goes out again. You do want to check what clock each sat is running. Not all of them run Cesium, infact most of them operate one of their Rubidium clocks, which IS more sensitive to eclipses. GPS OPERATIONAL ADVISORY 179 SUBJ: GPS STATUS 28 JUN 2009 1. SATELLITES, PLANES, AND CLOCKS (CS=CESIUM RB=RUBIDIUM): A. BLOCK I : NONE B. BLOCK II: PRNS 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 PLANE : SLOT B2, D1, C2, D4, B6, C5, A6, A3, A1, E3, D2, B4, F3, F1 CLOCK : RB, RB, CS, RB, RB, RB, RB, CS, CS, CS, RB, RB, RB, RB BLOCK II: PRNS 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28 PLANE : SLOT F2, B1, C4, E4, C3, E1, D3, E2, F4, D5, A5, F5, A4, B3 CLOCK : RB, RB, RB, RB, RB, RB, RB, RB, RB, CS, RB, RB, CS, RB BLOCK II: PRNS 29, 30, 31, 32 PLANE : SLOT C1, B5, A2, E5 CLOCK : RB, CS, RB, RB CS: 7 sats RB: 25 sats The GPS birds do see eclipses twice a year. Their timing signals is readily available and should allow you to monitor them. Notice that much of the timing error is canceled though broadcasted corrections, do study the GPS ICD 200. > (I apologize for for some OT content) I think it is sufficiently on-topic and enligthens yeat another aspect of our hobby in a perfectly good maner. Cheers, Magnus From magnus at rubidium.dyndns.org Sun Jun 28 23:35:05 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Mon, 29 Jun 2009 01:35:05 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: Message-ID: <4A47FE29.5060304@rubidium.dyndns.org> iovane at inwind.it wrote: > James Lux wrote: > >> Ah.. That's easy.. Pretty much every satellite in orbit derives its transmit >> frequency from a crystal oscillator, either a TCXO or a OCXO. So all you >> have to do is pick a LEO satellite that is easy to receive and measure the >> transmitted frequency, and that is at a frequency where other effects won't >> dominate (ionospheric uncertainties, for instance, probably rule out VHF and >> UHF downlinks). > > Hi James, > > that's easy for you at Nasa! You have rotary antennas, good receivers and so on... > I thought to GPS sats because there are cheap receivers all around, and hoped > the 1 PPS would tell something, so freeing me from considering doppler, relativity etc. > > Anyway, please let me know if you find any easily detectable signals that doesn't > require a tracking antenna. GPS will not help you at the PPS level, but you can avoid the tracking antenna anyway. The doppler-stuff and alot of other things is very well described. It is not hopeless, but not a very easy feather out of the hat thing. Cheers, Magnus From xde-l2g3 at myamail.com Sun Jun 28 22:52:57 2009 From: xde-l2g3 at myamail.com (Mike Monett) Date: Sun, 28 Jun 2009 19:52:57 -0300 Subject: [time-nuts] GPSDO project References: Message-ID: > GPSDO project > Brad Dye brad at braddye.com > Sun Jun 28 19:33:14 UTC 2009 > I have just purchased a Thunderbolt GPS receiver. I hope to use > this to discipline an oscillator on 66.66666 MHz so I can use it > as a LO on my Software Defined Receiver (SDR-IQ). > Building such an oscillator is a little over my head so I thought > I would ask the group if anyone knows where I could buy the > missing link of this project. I have put a drawing of my project > on the web showing the specs of what I need. The oscillator is > shown in the blue box. > Any help or suggestions would be greatly appreciated. > http://www.braddye.com/gps_do.html > 73s > Brad Dye K9IQY > ex KN9IQY, KN4BK, KM5NK, WB4JCF, ZP5TQ, WA4VXU, WA9RVL, /TI2, /9Y4, / > 6Y5, /KP4 As already mentioned, a DDS produces unwanted spurs. You can elminate them by using it backwards. 1. get a 66.6666MHz VCXO with good phase noise 2. drive the SDR as normally done 3. also drive a suitable DDS chip 4. set the DDS to produce 10MHz output with 66.6666MHz reference 5. feed the TBolt and DDS outputs to a 10MHz pfd 6. use loop filter to correct 66.6666MHz VCXO 7. you are now locked to GPS without the spurs from the DDS Simplified Diagram (view in fixed font) TBolt 10MHz -------------------------------> PLL Ref Loop Filt ---+ 66.6666MHz -----> DDS -----> 10MHz ------> PLL Clk | | OCXO I/P <------------------------------------------------------+ Trim the frequency by adjusting the DDS as desired, perhaps to give a slight offset to the receive frequency. Mike From james.p.lux at jpl.nasa.gov Mon Jun 29 00:01:15 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 28 Jun 2009 17:01:15 -0700 Subject: [time-nuts] Orbiting crystals In-Reply-To: Message-ID: On 6/28/09 3:23 PM, "iovane at inwind.it" wrote: > James Lux wrote: > >> Ah.. That's easy.. Pretty much every satellite in orbit derives its transmit >> frequency from a crystal oscillator, either a TCXO or a OCXO. So all you >> have to do is pick a LEO satellite that is easy to receive and measure the >> transmitted frequency, and that is at a frequency where other effects won't >> dominate (ionospheric uncertainties, for instance, probably rule out VHF and >> UHF downlinks). > > Hi James, > > that's easy for you at Nasa! You have rotary antennas, good receivers and so > on... > I thought to GPS sats because there are cheap receivers all around, and hoped > the 1 PPS would tell something, so freeing me from considering doppler, > relativity etc. There are lots of LEO satellites with signals detectable by an omni antenna. All you need is a downconverter to something easily digitizable (e.g. That you can feed into a sound card) and your trusty GPSDO to generate another signal that you digitize at the same time. As for (cheap) downconverters... That's a bit trickier. Maybe an eval board from NatSemi or Maxim > > Anyway, please let me know if you find any easily detectable signals that > doesn't > require a tracking antenna. Find one of those databases of LEO satellites and their frequencies, then look for a convenient band. > > Bye, > Antonio I8IOV > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From james.p.lux at jpl.nasa.gov Mon Jun 29 00:03:35 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 28 Jun 2009 17:03:35 -0700 Subject: [time-nuts] Orbiting crystals In-Reply-To: <4A47FE29.5060304@rubidium.dyndns.org> Message-ID: On 6/28/09 4:35 PM, "Magnus Danielson" wrote: > iovane at inwind.it wrote: >> James Lux wrote: >> >>> Ah.. That's easy.. Pretty much every satellite in orbit derives its transmit >>> frequency from a crystal oscillator, either a TCXO or a OCXO. So all you >>> have to do is pick a LEO satellite that is easy to receive and measure the >>> transmitted frequency, and that is at a frequency where other effects won't >>> dominate (ionospheric uncertainties, for instance, probably rule out VHF and >>> UHF downlinks). >> >> Hi James, >> >> that's easy for you at Nasa! You have rotary antennas, good receivers and so >> on... >> I thought to GPS sats because there are cheap receivers all around, and hoped >> the 1 PPS would tell something, so freeing me from considering doppler, >> relativity etc. >> >> Anyway, please let me know if you find any easily detectable signals that >> doesn't >> require a tracking antenna. > > GPS will not help you at the PPS level, but you can avoid the tracking > antenna anyway. The doppler-stuff and alot of other things is very well > described. It is not hopeless, but not a very easy feather out of the > hat thing. Basically, it's a sort of tedious whittling away. Once you have the basic capture receiver working, it's just modeling stuff and writing countless Matlab to remove this, that, and the other thing. Check out the paper by Peter Yoho for the analysis. My paper (with Jon Adams) describes the hardware. From peterawson at earthlink.net Mon Jun 29 00:27:38 2009 From: peterawson at earthlink.net (Pete) Date: Sun, 28 Jun 2009 18:27:38 -0600 Subject: [time-nuts] GPSDO project References: Message-ID: <2B542A790E3C4517AC6824684B38FEF2@BASE1> TI, AMD & National all make synthesizer chips which would work nicely. The problem is that they all charge $$$ for the evaluation kits, which would kake a very handy way to use them. Maybe you can sweet talk your local salesman into a freebie? Pete Rawson From hmurray at megapathdsl.net Mon Jun 29 00:41:04 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Sun, 28 Jun 2009 17:41:04 -0700 Subject: [time-nuts] GPSDO project In-Reply-To: Message from "Pete" of "Sun, 28 Jun 2009 18:27:38 MDT." <2B542A790E3C4517AC6824684B38FEF2@BASE1> Message-ID: <20090629004105.B2497BCEF@ip-64-139-1-69.sjc.megapath.net> > TI, AMD & National all make synthesizer chips which would work nicely. What sort of phase noise and/or spurs do they have? (relative to a good/OK crystal) Do the data sheets have good info? -- These are my opinions, not necessarily my employer's. I hate spam. From g4hup at btinternet.com Mon Jun 29 05:46:30 2009 From: g4hup at btinternet.com (dave powis) Date: Mon, 29 Jun 2009 05:46:30 +0000 (GMT) Subject: [time-nuts] GPSDO project - connecting external 66.667MHz into the SDR-IQ In-Reply-To: <4A47F4F2.CE327901@cox.net> References: <4A47F4F2.CE327901@cox.net> Message-ID: <386110.30043.qm@web86301.mail.ird.yahoo.com> See the pages on my web-site (http://g4hup.com) - instructions for connecting external LO signal to SDR-IQ are given there - these came from RFSpace. WW2R has implemented this with a small switch on the back panel of the SDR so he can use internal or external LO when available. Would be very interested to hear whether these same instructions apply to an SDR-14 - anyone prepared to open theirs up and have a look? 73, Dave, G4HUP ________________________________ From: WB6BNQ To: Discussion of precise time and frequency measurement Sent: Sunday, 28 June, 2009 11:55:46 PM Subject: Re: [time-nuts] GPSDO project Hi Brad, I am a little confused about your intentions. There is no mention on the RFspace web site about a provision of being able to feed in an external reference signal to the SDR-IQ or the SDR-14 for that matter. If you study the Analog devices AD6620 component, you will see that it is a 3.3 volt * * * ONLY * * * process, which only adds to the problem. Additionally there are constraints on the rise and fall times of the timing signal. This is a horrifically complex component with intricate dependencies tied to the specific A/D used. This is not your daddy's VFO from yester-year. The fact that the internal DDS is a digital function means you will never, ever, get to a perfect cardinal point, except under very special conditions. In this case it will have an offset of 16 pico-seconds because that is the smallest resolution the DDS can do. While small it would require very special hardware for you to keep it locked to the GPS. As the internal clocking system runs more then just the DDS, other considerations come into play. The "clocks" built to run these chips are not designed for external control and studying the physical layout of the SDR-IQ, it does not appear that they provided any means to have external clocking ability. Besides the computer's sound card DSP is heavily involved with regards to the "frequency" calibration. So there are two independent clocks to keep synchronized that are not related to the "listening time," particularly if you record the digital bits for later listening or analysis. Fortunately, the software will allow for you to calibrate, to some degree, but it is not and you will not be able to approach what you expect to do with the Thunderbolt. Keep in mind that the best you could do with a Thunderbolt on a 1 second per second comparison basis is only 1 part in 10 to the minus ninth (1x10^-9). It gets worse if you consider shorter times like a continuous analog aspect that you would have for active listening. The noise of the GPS system would mask the 16 pico-second resolution of the SDR-IQ DDS. The real problem is temperature. You could improve that by providing a chamber for the SDR-IQ and raising, carefully, the temperature to just above your highest ambient level. After all that, I am not saying you couldn't/wouldn't/shouldn't consider it. Keep in mind that the SDR-IQ, or for that matter, the SDR-14 DDS only sets the center of the 190 KHz bandwidth swath that you are viewing at any one time. The real fine aspect is done in the computer and the clocks in those are all over the map, so to speak. In order to have a really tight calibration, with "Timenuts" quality, would involve some serious effort to build a clocking system for both the SDR-IQ and the computer. The final result is you would still be offset due to the digital processes in both the SDR-IQ and the computer, plus, perhaps, some latency in the software. As I get to the point of sending this email I see that Dave Powis, G4HUP, has gone to the trouble to lock the SDR-IQ internal oscillator to an external 10 MHz. If you look at all the information on his web site, you will see that it is not a trivial project. As I pointed out, this only stabilizes the "window" of the SDR-IQ still leaving the computer to tend with. My experience with the Thunderbolt shows that it has some temperature dependencies and the expected nominal noise of the GPS system in the short term regard. What most people do is have a high quality "house" standard and do long term comparisons to the GPS. A high quality "house" standard would, in effect, filter the short term noise of the GPS system. At any rate, this is my fantasy and I am sticking to it ! Bill....WB6BNQ Brad Dye wrote: > I have just purchased a Thunderbolt GPS receiver. I hope to use this > to discipline an oscillator on 66.66666 MHz so I can use it as a LO on > my Software Defined Receiver (SDR-IQ). > > Building such an oscillator is a little over my head so I thought I > would ask the group if anyone knows where I could buy the missing link > of this project. I have put a drawing of my project on the web showing > the specs of what I need. The oscillator is shown in the blue box. > > Any help or suggestions would be greatly appreciated. > > http://www.braddye.com/gps_do.html > > 73s > > Brad Dye K9IQY > ex KN9IQY, KN4BK, KM5NK, WB4JCF, ZP5TQ, WA4VXU, WA9RVL, /TI2, /9Y4, / > 6Y5, /KP4 > 52 years as a FCC licensed amateur radio operator > 36 years as a FCC licensed first class commercial radio operator > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From m0ycm at veenstras.com Mon Jun 29 05:48:57 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Mon, 29 Jun 2009 06:48:57 +0100 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: Message-ID: <6B1A68CA627A45CB95597CE243F412AF@hp> INMARSATS Look at tracking beacons vs AFC pilots Lester B Veenstra M?YCM K1YCM lester at veenstras.com m0ycm at veenstras.com k1ycm at veenstras.com This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of iovane at inwind.it ............... Anyway, please let me know if you find any easily detectable signals that doesn't require a tracking antenna. From james.p.lux at jpl.nasa.gov Mon Jun 29 06:02:49 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 28 Jun 2009 23:02:49 -0700 Subject: [time-nuts] Orbiting crystals In-Reply-To: <6B1A68CA627A45CB95597CE243F412AF@hp> Message-ID: Isn?t Inmarsat in a Clarke Orbit? If the propagation path for the solar eclipse shadow experiment runs through the eclipse with the path from Clarke orbit to you, then there's tons of signals available to look at. On 6/28/09 10:48 PM, "Lester Veenstra" wrote: > INMARSATS Look at tracking beacons vs AFC pilots > > > Lester B Veenstra M?YCM K1YCM > lester at veenstras.com > m0ycm at veenstras.com > k1ycm at veenstras.com > > > This e-mail and any documents attached hereto contain confidential or > privileged information. The information is intended to be for use only by > the individual or entity to whom they are addressed. If you are not the > intended recipient or the person responsible for delivering the e-mail to > the intended recipient, be aware that any disclosure, copying, distribution > or use of the contents of this e-mail or any documents attached hereto is > prohibited. > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of iovane at inwind.it > ............... > > Anyway, please let me know if you find any easily detectable signals that > doesn't require a tracking antenna. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From christophe.huygens at cs.kuleuven.ac.be Mon Jun 29 07:01:18 2009 From: christophe.huygens at cs.kuleuven.ac.be (Christophe Huygens) Date: Mon, 29 Jun 2009 09:01:18 +0200 Subject: [time-nuts] Generating 66.666...MHz from 10MHz In-Reply-To: References: Message-ID: <4A4866BE.7080404@cs.kuleuven.ac.be> My solution is to lock a 1GHZ Crystek resonator to 10MHz, and then use this to drive a DDS AD9912. Recent generations of DDS are quite impressive. http://www.qslnet.de/member/on4iy/9912.html Xtof. Murray Greenman wrote: > Here's an idea which actually works (I tried it). Rather than lock at > 10MHz, you lock directly to 1pps. > > You can lock an XO to 1/3 Hz steps by locking to 1pps and ignoring two > out of three results from the TIC. I did it at 7.333MHz, using an > AT90S2313 micro, and you could just as easily do it at 8.333... and then > multiply by 8. > > Yes, it does leave you with a very low loop frequency! Although I've not > tried it, you could potentially add 120 degrees equivalent to one > intermediate TIC result and subtract 120 degrees from the next, and so > lock at 1Hz. > > 73, > Murray ZL1BPU > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. -------------- next part -------------- A non-text attachment was scrubbed... Name: christophe_huygens.vcf Type: text/x-vcard Size: 328 bytes Desc: not available URL: From cupido at mail.ua.pt Mon Jun 29 09:23:56 2009 From: cupido at mail.ua.pt (Luis Cupido) Date: Mon, 29 Jun 2009 10:23:56 +0100 Subject: [time-nuts] GPSDO project - 66.667MHz from 10MHz In-Reply-To: <690441.15168.qm@web86305.mail.ird.yahoo.com> References: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> <4A47E901.5000309@xtra.co.nz> <690441.15168.qm@web86305.mail.ird.yahoo.com> Message-ID: <4A48882C.5010108@mail.ua.pt> Both for locking with a 10MHz or 1pps you have a single chip solution using one of my reflock designs. http://w3ref.cfn.ist.utl.pt/cupido/reflock.html For a 1pps lock of fractional 1/3 frequencies you have already a code. (check the list of files for reflock 1) For locking a 66.666(6) VCXO to 10MHz you can use the same reflock I design and the configuration is kind of trivial (but no one asked for it before) and I can make a file for you. Luis Cupido ct1dmk. > ________________________________ > From: Bruce Griffiths > To: Discussion of precise time and frequency measurement > Sent: Sunday, 28 June, 2009 11:04:49 PM > Subject: Re: [time-nuts] GPSDO project > > Hal Murray wrote: >> You want 66.6666 MHz from 10 MHz. >> >> I can think of several approaches. >> >> 1) Patch the radio stuff to work with 10 MHz. Since 10 MHz is common from >> things like GPSDOs or Telco surplus rubidium clocks, somebody may have done >> that already. >> >> 2) Build a PLL. The first step is probably to find a 66.666 MHz oscillator >> that has an external fine tuning pin. Then it's divide by 20 and 3, compare, >> filter... >> >> 3) Get to 66.666 MHz by dividing by 3 then multiplying by 2 and 5. I don't >> know much about this area, but there was a lot of discussion here a few >> months ago. Check the archives. >> > > Actually need to multiply 3.333.. MHz by 20 (5 x 2 x 2) > No need to multiply by 2 or 4, if the output of the divide by 3 is a 1/3 > duty cycle square wave, one can extract the 2nd (or 4th) harmonic of the > square wave repetition rate with a filter. > Amplify and multiply by 5 (can use the same approach as used in the > 5370A/B frequency multiplier chain (1 transistor per multiplier) and filter. > > A high level injection locked divider can have lower close in phase > noise than a digital one. > >> 4) Use a DDS chip to synthesize 66.666 MHz. Analog Devices makes lots of >> nice ones. One problem with DDSes is that they normally make spurs. But >> they aren't a problem if the target frequency is a clean multiple of the >> source frequency. 20/3 doesn't sound clean, but I'd have to do a lot of work >> to check the details. There may be a clean frequency that is close enough to >> 66.666 MHz and/or one that has spurs that are far enough out so you can >> filter them. >> >> 5) Use a low cost 66.666 MHz oscillator and live with the error. You may be >> able to correct any errors. The key step would be to feed the 66.666 MHz to >> a counter running off the T-Bolt clock so you know the real frequency of your >> 66.666 MHz osc. Suppose your 66.666 MHz is 73 ppm fast and you want to >> listen to 12.123 MHz. You would set the radio to listen to 73 PPM below >> 12.123 MHz. >> >> >> >> > > Bruce > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From mcleann at bigpond.com Mon Jun 29 10:16:54 2009 From: mcleann at bigpond.com (Nic McLean) Date: Mon, 29 Jun 2009 20:16:54 +1000 Subject: [time-nuts] GPSDO project - 66.667MHz from 10MHz In-Reply-To: <4A48882C.5010108@mail.ua.pt> References: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> <4A47E901.5000309@xtra.co.nz><690441.15168.qm@web86305.mail.ird.yahoo.com> <4A48882C.5010108@mail.ua.pt> Message-ID: <1E726D54F45D4B0C885153EED73A5FAF@PC755913417801> Hi Luis, Are kits available again for your design? 73's Nic VK2KXN / VK5ZAT Subject: Re: [time-nuts] GPSDO project - 66.667MHz from 10MHz Both for locking with a 10MHz or 1pps you have a single chip solution using one of my reflock designs. http://w3ref.cfn.ist.utl.pt/cupido/reflock.html For a 1pps lock of fractional 1/3 frequencies you have already a code. (check the list of files for reflock 1) For locking a 66.666(6) VCXO to 10MHz you can use the same reflock I design and the configuration is kind of trivial (but no one asked for it before) and I can make a file for you. Luis Cupido ct1dmk. From cupido at mail.ua.pt Mon Jun 29 11:18:15 2009 From: cupido at mail.ua.pt (Luis Cupido) Date: Mon, 29 Jun 2009 12:18:15 +0100 Subject: [time-nuts] GPSDO project - 66.667MHz from 10MHz In-Reply-To: <1E726D54F45D4B0C885153EED73A5FAF@PC755913417801> References: <20090628213829.408D5BCEF@ip-64-139-1-69.sjc.megapath.net> <4A47E901.5000309@xtra.co.nz><690441.15168.qm@web86305.mail.ird.yahoo.com> <4A48882C.5010108@mail.ua.pt> <1E726D54F45D4B0C885153EED73A5FAF@PC755913417801> Message-ID: <4A48A2F7.7090606@mail.ua.pt> Nic, I think yes but I'm not sure, please check Darrel's VE1ALQ and NTMS(Kent Britain) for reflock I pcb's and/or kits (as I've not heard from them recently). I believe TAPR is no longer offering the reflock II kit :-( Luis Cupido ct1dmk. Nic McLean wrote: > Hi Luis, > Are kits available again for your design? > 73's > Nic > VK2KXN / VK5ZAT > > > Subject: Re: [time-nuts] GPSDO project - 66.667MHz from 10MHz > > Both for locking with a 10MHz or 1pps you have a > single chip solution using one of my reflock designs. > > http://w3ref.cfn.ist.utl.pt/cupido/reflock.html > > For a 1pps lock of fractional 1/3 frequencies you have > already a code. (check the list of files for reflock 1) > > For locking a 66.666(6) VCXO to 10MHz you can use the same > reflock I design and the configuration is kind of trivial > (but no one asked for it before) and I can make a file > for you. > > Luis Cupido > ct1dmk. > > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From Arnold.Tibus at gmx.de Mon Jun 29 11:36:30 2009 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Mon, 29 Jun 2009 13:36:30 +0200 Subject: [time-nuts] Lady Heather update in progress In-Reply-To: Message-ID: Hi Mark, I should have red the instructions better, it does work as wanted - great, thank you! >Hello Arnold, >That feature is already in the current release (v 2.0). You can use the 'w' keyboard command to write the data to a file. You can select either the complete buffer or just the time span displayed on the screen. >--------------------------- >normally I do run LH without the log option tick. but in some cases >it would be fine for me to have still the option to save (or discard) the >data when stopping the program. >_____________ regards, Arnold From jpalacio at roa.es Mon Jun 29 11:47:42 2009 From: jpalacio at roa.es (Juan Palacio) Date: Mon, 29 Jun 2009 11:47:42 -0000 Subject: [time-nuts] Patek Phillipe Telequartz Message-ID: <3F518FF2656D450DAF4AAFFB064D9F58@horajefe> Hello. I have received a Patek Phillipe's Telequartz master clock . This device can distribute 1 minute 24 V pulses to control several clocks. It also can receive a radio signal to synchronise the local time scale. Unfortunately I did not receive a copy of the manual. I will appreciate if any of the members of the group could share the manual or any information about this clock to put it into operation. Best wishes, Juan Juan Palacio From brad at braddye.com Mon Jun 29 13:08:15 2009 From: brad at braddye.com (Brad Dye) Date: Mon, 29 Jun 2009 08:08:15 -0500 Subject: [time-nuts] GPSDO project Message-ID: Many thanks to all who responded to my request for help on this project. The SDR-IQ (http://www.rfspace.com/SDR-IQ.html) already has a built-in 66.6667 MHz osc, I just want to make it more stable and reasonably accurate, as I use it as a general coverage HF receiver with a one- Hertz read-out. There is a place for a surface-mount jack on the PC board -- so that an external osc can be used -- although this feature is not promoted by the manufacturer. This SDR does most of its own processing in hardware and doesn't rely on a computer sound card as much as some SDRs do. There was one response, offering a kit to do what I need, but it requires more test equipment for tuning and calibration than what I have available. I am still looking for a simple, completed oscillator that will accept 10 MHz from a Thunderbolt GPS receiver and supply 66.66666 MHz for my SDR as described here: http://www.braddye.com/gps_do.html My background is in radio paging where we use GPS receivers to keep our 900 MHz transmitters on frequency for simulcast operation. I really appreciate the time everyone took to offer suggestions. 73s Brad Dye, K9IQY Springfield, Illinois From christophe.huygens at cs.kuleuven.ac.be Mon Jun 29 13:19:13 2009 From: christophe.huygens at cs.kuleuven.ac.be (Christophe Huygens) Date: Mon, 29 Jun 2009 15:19:13 +0200 Subject: [time-nuts] GPSDO project In-Reply-To: References: Message-ID: <4A48BF51.8060100@cs.kuleuven.ac.be> Consider a 2nd hand low phase noise source like a PTS-160. Best regards, Xtof. Brad Dye wrote: > Many thanks to all who responded to my request for help on this project. > > The SDR-IQ (http://www.rfspace.com/SDR-IQ.html) already has a built-in > 66.6667 MHz osc, I just want to make it more stable and reasonably > accurate, as I use it as a general coverage HF receiver with a one-Hertz > read-out. There is a place for a surface-mount jack on the PC board -- > so that an external osc can be used -- although this feature is not > promoted by the manufacturer. This SDR does most of its own processing > in hardware and doesn't rely on a computer sound card as much as some > SDRs do. > > There was one response, offering a kit to do what I need, but it > requires more test equipment for tuning and calibration than what I have > available. I am still looking for a simple, completed oscillator that > will accept 10 MHz from a Thunderbolt GPS receiver and supply 66.66666 > MHz for my SDR as described here: > > http://www.braddye.com/gps_do.html > > My background is in radio paging where we use GPS receivers to keep our > 900 MHz transmitters on frequency for simulcast operation. I really > appreciate the time everyone took to offer suggestions. > > 73s > > Brad Dye, K9IQY > Springfield, Illinois > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. -------------- next part -------------- A non-text attachment was scrubbed... Name: christophe_huygens.vcf Type: text/x-vcard Size: 328 bytes Desc: not available URL: From dave at uk-ar.co.uk Mon Jun 29 15:48:28 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Mon, 29 Jun 2009 16:48:28 +0100 Subject: [time-nuts] GPSDO project (SDR) In-Reply-To: Message-ID: Hi Brad. Just catching up with this, after a hot weekend, and doing "White Van Man" impressions on (an even hotter) M1 this morning... Personally, I wouldn't bother with any high accuracy clock/oscillator for the SDR, unless you can also synch the AD sampling clock in the soundcard. As that will have much more of an effect on carrier frequency generation/indication etc than even an undisciplined oscillator in the SDR mixer itself. Then there is the issue of just how accurate is the software in it's DSP routines in interpreting the (sampled) data from the soundcard. Much SDR software has a "frequency calibration" function, as it is well known that most consumer soundcards are not that accurate in their timing, not just that the RF>I/Q mixer clock is often off a bit. Even some of the 96k sampling 24 bit "golden ears" types can be somewhat wayward. Have you also ascertained that Power SDR run's OK on Vista? Only ask, as I know that others have found "Big" trouble with much SDR software, and the way it tries to use the PC's sound system, and how that interacts with Vista's way of doing things. I've not run Power SDR myself on anything other than demo files on XP/2000 by the way. Vista's background timekeeping is crap too I'm told, quite how that will impact SDR software though, I do not know. Check out the SDR lists on Yahoo, their maybe people there who have done what you describe, but I also monitor those lists too, and can't recall anyone doing that (GPSDO) thing with the mixer osc'. Though there has been much discussion about soundcard sampling clocks! http://groups.yahoo.com/group/softrock40/join Also the KGKSDR list, the address of escapes me at the moment. There are probably others. Wonder if anyone has integrated "ClickLock" into any SDR software yet... 73. Dave G0WBX. > -----Original Message----- > In a message dated 28/06/2009 20:34:25 GMT Daylight Time, > brad at braddye.com > writes: > > I have just purchased a Thunderbolt GPS receiver. I hope to > use this > to discipline an oscillator on 66.66666 MHz so I can use it > as a LO on > my Software Defined Receiver (SDR-IQ). > > Building such an oscillator is a little over my head so I thought I > would ask the group if anyone knows where I could buy the > missing link > of this project. I have put a drawing of my project on the > web showing > the specs of what I need. The oscillator is shown in the blue box. > > Any help or suggestions would be greatly appreciated. > > http://www.braddye.com/gps_do.html From m0ycm at veenstras.com Mon Jun 29 18:21:52 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Mon, 29 Jun 2009 19:21:52 +0100 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: <6B1A68CA627A45CB95597CE243F412AF@hp> Message-ID: <6FBB12E601CC497AB7A085D667237947@hp> James: I am afraid you lost me; " can you illuminate (NPI) us on what the "experiment" is. Is this a leo satellite with an L-Band downlink? Les Lester B Veenstra M?YCM K1YCM lester at veenstras.com m0ycm at veenstras.com k1ycm at veenstras.com -----Original Message----- From: Lux, James P [mailto:james.p.lux at jpl.nasa.gov] ........... Isn?t Inmarsat in a Clarke Orbit? If the propagation path for the solar eclipse shadow experiment runs through the eclipse with the path from Clarke orbit to you, then there's tons of signals available to look at............ From james.p.lux at jpl.nasa.gov Mon Jun 29 18:35:53 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Mon, 29 Jun 2009 11:35:53 -0700 Subject: [time-nuts] Orbiting crystals In-Reply-To: <6FBB12E601CC497AB7A085D667237947@hp> References: <6B1A68CA627A45CB95597CE243F412AF@hp> <6FBB12E601CC497AB7A085D667237947@hp> Message-ID: > -----Original Message----- > From: Lester Veenstra [mailto:m0ycm at veenstras.com] > Sent: Monday, June 29, 2009 11:22 AM > To: Lux, James P; lester at veenstras.com; 'Discussion of > precise timeand frequency measurement' > Subject: RE: [time-nuts] Orbiting crystals > > James: > I am afraid you lost me; " can you illuminate (NPI) us on > what the "experiment" is. Is this a leo satellite with an > L-Band downlink? > Les > > > Lester B Veenstra M?YCM K1YCM > lester at veenstras.com > m0ycm at veenstras.com > k1ycm at veenstras.com > > > > -----Original Message----- > From: Lux, James P [mailto:james.p.lux at jpl.nasa.gov] ........... > > Isn?t Inmarsat in a Clarke Orbit? If the propagation path > for the solar eclipse shadow experiment runs through the > eclipse with the path from Clarke orbit to you, then there's > tons of signals available to look at............ > > I think the idea was to look for jumps in a crystal oscillator when it goes through the shadow of a total eclipse. My original suggestion was to look for LEO satellites which had conveniently monitorable oscillator frequencies. Someone else suggested using Inmarsat (because they have a L-band pilot tone), but I think the Inmarsat birds are in Clarke orbit, so you'd have to pick your ground station location (essentially in line with the sun and the bird) to do the test. From m0ycm at veenstras.com Mon Jun 29 18:54:20 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Mon, 29 Jun 2009 19:54:20 +0100 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: <6B1A68CA627A45CB95597CE243F412AF@hp><6FBB12E601CC497AB7A085D667237947@hp> Message-ID: Now this begins to make some sense; Of course the geosync satellites do go into eclipse season trice a year, during which each day the satellite is passing through the Earth's shadow for a variable period. To pass though the shadow of a solar lunar eclipse, the eclipse would have to be visible on the ground at satellite sub-satellite point ( nominal, the equator). For the Inmarsat's this would be at: 24.8 E 25.1 E 64.5 E 109.0 E 143.5 E 178.1 E 218.0 $ 261.9 E 262.4 E 306.0 E 344.5 E But, since there are satellites virtually anywhere along the arc, there is no reason to restrict observations to INMARSAT. But INMARSATs do provide a easy target for an observer with simple L-Band equipment. Of course I would expect to see a shift in an onboard crystal frequency (but not a "jump") simply from the thermal changes. Lester B Veenstra M?YCM K1YCM lester at veenstras.com m0ycm at veenstras.com k1ycm at veenstras.com -----Original Message----- From: Lux, James P [mailto:james.p.lux at jpl.nasa.gov] Sent: Monday, June 29, 2009 7:36 PM To: lester at veenstras.com; 'Discussion of precisetimeand frequency measurement' Subject: RE: [time-nuts] Orbiting crystals > -----Original Message----- ................. I think the idea was to look for jumps in a crystal oscillator when it goes through the shadow of a total eclipse. My original suggestion was to look for LEO satellites which had conveniently monitorable oscillator frequencies. Someone else suggested using Inmarsat (because they have a L-band pilot tone), but I think the Inmarsat birds are in Clarke orbit, so you'd have to pick your ground station location (essentially in line with the sun and the bird) to do the test. From magnus at rubidium.dyndns.org Mon Jun 29 19:05:18 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Mon, 29 Jun 2009 21:05:18 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: <6B1A68CA627A45CB95597CE243F412AF@hp><6FBB12E601CC497AB7A085D667237947@hp> Message-ID: <4A49106E.2070704@rubidium.dyndns.org> Lester Veenstra wrote: > Now this begins to make some sense; > > Of course the geosync satellites do go into eclipse season trice a year, > during which each day the satellite is passing through the Earth's shadow > for a variable period. > > To pass though the shadow of a solar lunar eclipse, the eclipse would have > to be visible on the ground at satellite sub-satellite point ( nominal, the > equator). For the Inmarsat's this would be at: > > 24.8 E > 25.1 E > 64.5 E > 109.0 E > 143.5 E > 178.1 E > 218.0 $ > 261.9 E > 262.4 E > 306.0 E > 344.5 E > > But, since there are satellites virtually anywhere along the arc, there is > no reason to restrict observations to INMARSAT. But INMARSATs do provide a > easy target for an observer with simple L-Band equipment. > > Of course I would expect to see a shift in an onboard crystal frequency (but > not a "jump") simply from the thermal changes. It was assumed that the crystals was locked to Cesium or Rubidium, and hence it would chase up the error. Cheers, Magnus From m0ycm at veenstras.com Mon Jun 29 19:19:17 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Mon, 29 Jun 2009 20:19:17 +0100 Subject: [time-nuts] Orbiting crystals In-Reply-To: <4A49106E.2070704@rubidium.dyndns.org> References: <6B1A68CA627A45CB95597CE243F412AF@hp><6FBB12E601CC497AB7A085D667237947@hp> <4A49106E.2070704@rubidium.dyndns.org> Message-ID: Sorry, but no such luck on the commercial satcoms. Lester B Veenstra M?YCM K1YCM lester at veenstras.com m0ycm at veenstras.com k1ycm at veenstras.com -----Original Message----- .................... It was assumed that the crystals was locked to Cesium or Rubidium, and hence it would chase up the error. Cheers, Magnus From magnus at rubidium.dyndns.org Mon Jun 29 19:31:46 2009 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Mon, 29 Jun 2009 21:31:46 +0200 Subject: [time-nuts] Orbiting crystals In-Reply-To: References: <6B1A68CA627A45CB95597CE243F412AF@hp><6FBB12E601CC497AB7A085D667237947@hp> <4A49106E.2070704@rubidium.dyndns.org> Message-ID: <4A4916A2.4030905@rubidium.dyndns.org> Lester Veenstra wrote: > Sorry, but no such luck on the commercial satcoms. It was a mear assumption, not a requirement. A pure crystal solution would do fine, as the goal was really to measure if the effect is real. The IGS network have already done this, and published the results, and they have done it according to the lines I scetched, since they have the setups needed. I was just not sure they also produced that kind of output from their data, but adding it as an additional product isn't too hard onces all the other things is set up. The UFFC site turned up alot of useful stuff once searching for "orbit". Cheers, Magnus From brad at braddye.com Mon Jun 29 21:50:12 2009 From: brad at braddye.com (Brad Dye) Date: Mon, 29 Jun 2009 16:50:12 -0500 Subject: [time-nuts] GPSDO project Message-ID: <78118A2D-6168-4481-AA82-89EE20B50E81@braddye.com> Does anyone have a Reflock that they would sell me? Best regards, Brad Dye K9IQYom From dibene at usa.net Mon Jun 29 22:20:50 2009 From: dibene at usa.net (Alberto di Bene) Date: Tue, 30 Jun 2009 00:20:50 +0200 Subject: [time-nuts] GPSDO project (SDR) In-Reply-To: References: Message-ID: <4A493E42.4010704@usa.net> Dave Baxter wrote: > > Personally, I wouldn't bother with any high accuracy clock/oscillator > for the SDR, unless you can also synch the AD sampling clock in the > soundcard. The SDR-IQ, SDR-14, Qs1r, Perseus and the HPSDR project do not rely on a sound card ADC to sample any signals..... The RF signal is directly sampled at RF, with sampling rates up to 122.88 MHz (depending on the model), then it is frequency-shifted, then downsampled by the firmware in the accompanying FPGA. Then the downsampled stream is sent to the PC via the USB 2.0 port. The software on the PC receives directly digital data, no pesky sound card is needed to digitize it. So the _only_ factor affecting the frequency calibration is the clock of the RF ADC. 73 Alberto I2PHD From stanw1le at verizon.net Mon Jun 29 23:41:40 2009 From: stanw1le at verizon.net (Stan W1LE) Date: Mon, 29 Jun 2009 19:41:40 -0400 Subject: [time-nuts] GPSDO project In-Reply-To: <78118A2D-6168-4481-AA82-89EE20B50E81@braddye.com> References: <78118A2D-6168-4481-AA82-89EE20B50E81@braddye.com> Message-ID: <4A495134.7040206@verizon.net> Hello Brad, VE1ALQ has them. He will also make VCXO's. Do a google search for his webpages. He sells the kits as well as the assembled units. By far easier to get a PTS or Fluke sysnthesizer. Stan, W1LE Brad Dye wrote: > Does anyone have a Reflock that they would sell me? > > > > Best regards, > > Brad Dye > K9IQYom > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From David.Hilton-Jones at clneuro.ox.ac.uk Tue Jun 30 12:28:07 2009 From: David.Hilton-Jones at clneuro.ox.ac.uk (David Hilton-Jones) Date: Tue, 30 Jun 2009 13:28:07 +0100 Subject: [time-nuts] (no subject) Message-ID: <4A4A12E7020000690001710C@gwmail.jr2.ox.ac.uk> I am not very much interested in how it is achieved, but wonder if a 10MHz oscillator locked to GPS is now available as "plug&play" rather than needing a lot of time/effort/building. I note the Thunderbolt units available from the Far East on ebay for~?80gbp. Are these really P&P - that is, just connect PSU and aerial and out comes 10MHz locked to GPS? Is it necessary to connect to a computer via the RS232 link, or is that just there if you want to fiddle and be clever? If so, then this may be preferrable to running my rubidium source continuously. What I am interested in is stability, not ultiamte accuracy. As always, sorry for the naivety of the question. Thanks David, G4YTL From david.partridge at dsl.pipex.com Tue Jun 30 12:48:57 2009 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Tue, 30 Jun 2009 13:48:57 +0100 Subject: [time-nuts] (no subject) In-Reply-To: <4A4A12E7020000690001710C@gwmail.jr2.ox.ac.uk> References: <4A4A12E7020000690001710C@gwmail.jr2.ox.ac.uk> Message-ID: <5707E80AD6E74CE3922245EF745DDBD3@APOLLO> Yes the Thunderbold truly is plug and play. In holdover of course the Rb will be more stable ... The RS-232 connection also lets you see if it has achieved GPS lock - you can't tell without something that talks to the RS-232 interface. Dave -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of David Hilton-Jones Sent: 30 June 2009 13:28 To: time-nuts at febo.com Subject: [time-nuts] (no subject) I am not very much interested in how it is achieved, but wonder if a 10MHz oscillator locked to GPS is now available as "plug&play" rather than needing a lot of time/effort/building. I note the Thunderbolt units available from the Far East on ebay for~?80gbp. Are these really P&P - that is, just connect PSU and aerial and out comes 10MHz locked to GPS? Is it necessary to connect to a computer via the RS232 link, or is that just there if you want to fiddle and be clever? If so, then this may be preferrable to running my rubidium source continuously. What I am interested in is stability, not ultiamte accuracy. As always, sorry for the naivety of the question. Thanks David, G4YTL _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From jltran at worldnet.att.net Tue Jun 30 13:12:38 2009 From: jltran at worldnet.att.net (J. L. Trantham) Date: Tue, 30 Jun 2009 08:12:38 -0500 Subject: [time-nuts] (no subject) In-Reply-To: <5707E80AD6E74CE3922245EF745DDBD3@APOLLO> Message-ID: <8C842DA8259845CCB209D7C13EF0687A@S0028384766> The Z3816A and Z3801A are plug and play with 4 LED status lights on the front panel including GPS Lock. I have the Thunderbolt and a Z3816A and find being able to review the information on the computer is very helpful including looking for satellite tracking loss, open or shorter antenna connections, etc. If you have an old laptop or other computer, it is simple to connect via a serial port and communicate via Tboltmon.exe or SatStat.exe. You might look here (http://www.realhamradio.com/GPS_Frequency_Standard.htm) for more information. I have been playing with a 5061A and 5061B by looking at their outputs on a scope triggered by a Thunderbolt and I am amazed that I can generate a signal in my workshop that exactly matches the frequency of the Thunderbolt linked to the NIST reference. (Sorry for the 'simple' description, I have not yet made it to phase noise and stability comparisons). -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of David C. Partridge Sent: Tuesday, June 30, 2009 7:49 AM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] (no subject) Yes the Thunderbold truly is plug and play. In holdover of course the Rb will be more stable ... The RS-232 connection also lets you see if it has achieved GPS lock - you can't tell without something that talks to the RS-232 interface. Dave -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of David Hilton-Jones Sent: 30 June 2009 13:28 To: time-nuts at febo.com Subject: [time-nuts] (no subject) I am not very much interested in how it is achieved, but wonder if a 10MHz oscillator locked to GPS is now available as "plug&play" rather than needing a lot of time/effort/building. I note the Thunderbolt units available from the Far East on ebay for~?80gbp. Are these really P&P - that is, just connect PSU and aerial and out comes 10MHz locked to GPS? Is it necessary to connect to a computer via the RS232 link, or is that just there if you want to fiddle and be clever? If so, then this may be preferrable to running my rubidium source continuously. What I am interested in is stability, not ultiamte accuracy. As always, sorry for the naivety of the question. Thanks David, G4YTL _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From dave at uk-ar.co.uk Tue Jun 30 15:21:31 2009 From: dave at uk-ar.co.uk (Dave Baxter) Date: Tue, 30 Jun 2009 16:21:31 +0100 Subject: [time-nuts] time-nuts Digest, Vol 59, Issue 97 In-Reply-To: Message-ID: > Message: 3 > Date: Tue, 30 Jun 2009 00:20:50 +0200 > From: Alberto di Bene > Subject: Re: [time-nuts] GPSDO project (SDR) > To: Discussion of precise time and frequency measurement > > Message-ID: <4A493E42.4010704 at usa.net> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Dave Baxter wrote: > > > > Personally, I wouldn't bother with any high accuracy > clock/oscillator > > for the SDR, unless you can also synch the AD sampling clock in the > > soundcard. > > The SDR-IQ, SDR-14, Qs1r, Perseus and the HPSDR project do > not rely on a sound card ADC to sample any signals..... > The RF signal is directly sampled at RF, with sampling rates > up to 122.88 MHz (depending on the model), then it is > frequency-shifted, then downsampled by the firmware in the > accompanying FPGA. Then the downsampled stream is sent to the > PC via the USB 2.0 port. The software on the PC receives > directly digital data, no pesky sound card is needed to digitize it. > > So the _only_ factor affecting the frequency calibration is > the clock of the RF ADC. > > 73 Alberto I2PHD In that case, it's the RF ADC clock that needs locking. No doubt that is controled by the 66.666MHz reference much discussed? (I do not have schematics / info on that device.) Either way, I stil doubt GPS locking it would be of much great benefit. With the exception of checking the accuracy of some Standard Time and Frequency transmissions, I can't think of any real reason to do it, other than "because we can"? It's also that much more stuff to potentialy go wrong at a moments notice. Thinking of the KISS principle, not exactly in the HPSDR line of things. Mind you, you should see my shack, and the over complicated system I've created to monitor HF beacons! ;-) Currently down due to an overheating CPU in one machine. 73.. Dave G0WBX. PS: I think I've got the NTP timekeeping machine configured sorted and running, now waiting for the replacement 1PPS sourcing GPS rx to arrive. From pete at petelancashire.com Tue Jun 30 16:34:43 2009 From: pete at petelancashire.com (Pete Lancashire) Date: Tue, 30 Jun 2009 09:34:43 -0700 Subject: [time-nuts] manual for a Spectracom 9161 ? In-Reply-To: References: Message-ID: <329872be7a820a1332ceb1eb6fd4a63b.squirrel@petelancashire.com> I'm sorting through the junk I have been bringing home and have a Spectracom 1961 w/o its antenna, and it does blows its fuse when plugged in. -pete From holrum at hotmail.com Tue Jun 30 16:46:53 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 30 Jun 2009 16:46:53 +0000 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: Message-ID: There is one thing that make most GPSDOs not quite plug and play... that is their need to know their location rather precisely. They do this with a "self survey" mechanism. The self survey can take several hours. Most units can trigger this automatically if their location changes more than a specific amount. You are better off manually triggering the self survey and saving the results in the unit. Unless you do this, the unit might go into self-survey mode every time the power cycles or might get confused trying to use the old location. ---------------------------------------- _________________________________________________________________ Windows Live?: Keep your life in sync. http://windowslive.com/explore?ocid=TXT_TAGLM_WL_BR_life_in_synch_062009 From David.Hilton-Jones at clneuro.ox.ac.uk Tue Jun 30 16:56:09 2009 From: David.Hilton-Jones at clneuro.ox.ac.uk (David Hilton-Jones) Date: Tue, 30 Jun 2009 17:56:09 +0100 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) Message-ID: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> Many thanks Mark. I was thinking of setting up in a fixed position and leaving on permanently. But then if there's a power cut? Do you know if the China supplier is OK? Or any source in the UK of Thunderbolt? David >>> Mark Sims 30/06/09 17:48 >>> There is one thing that make most GPSDOs not quite plug and play... that is their need to know their location rather precisely. They do this with a "self survey" mechanism. The self survey can take several hours. Most units can trigger this automatically if their location changes more than a specific amount. You are better off manually triggering the self survey and saving the results in the unit. Unless you do this, the unit might go into self-survey mode every time the power cycles or might get confused trying to use the old location. ---------------------------------------- _________________________________________________________________ Windows Live?: Keep your life in sync. http://windowslive.com/explore?ocid=TXT_TAGLM_WL_BR_life_in_synch_062009 _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From rdarlington at gmail.com Tue Jun 30 17:03:19 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Tue, 30 Jun 2009 11:03:19 -0600 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> References: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> Message-ID: I have my equipment attached to a rather large (100+ pounds) UPS device in case of a power outage. It'll run a Thunderbolt for a week I'd suspect. I've purchased several items from fluke.l (that's an L not a one) on eBay with good results every time. The only "problem" I ever had was just this week when I ordered a pair of Panasonic VIC100 antennas. I asked him to throw in two TNC to F adapters so I could go to ordinary RadioShack cable TV cable. I received two TNC to N instead. This cost me $5! No complaints, just a minor annoyance, but now I have a pair of adapters I didn't have before and I made due with a Pamona adapter kit till I find a proper replacement. -Bob On Tue, Jun 30, 2009 at 10:56 AM, David Hilton-Jones < David.Hilton-Jones at clneuro.ox.ac.uk> wrote: > Many thanks Mark. > > I was thinking of setting up in a fixed position and leaving on > permanently. But then if there's a power cut? > > Do you know if the China supplier is OK? Or any source in the UK of > Thunderbolt? > > David > > >>> Mark Sims 30/06/09 17:48 >>> > > There is one thing that make most GPSDOs not quite plug and play... > that is their need to know their location rather precisely. They do > this with a "self survey" mechanism. The self survey can take several > hours. Most units can trigger this automatically if their location > changes more than a specific amount. > > You are better off manually triggering the self survey and saving the > results in the unit. Unless you do this, the unit might go into > self-survey mode every time the power cycles or might get confused > trying to use the old location. > > > ---------------------------------------- > > > _________________________________________________________________ > Windows Live?: Keep your life in sync. > http://windowslive.com/explore?ocid=TXT_TAGLM_WL_BR_life_in_synch_062009 > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From hmurray at megapathdsl.net Tue Jun 30 17:44:35 2009 From: hmurray at megapathdsl.net (Hal Murray) Date: Tue, 30 Jun 2009 10:44:35 -0700 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: Message from "David Hilton-Jones" of "Tue, 30 Jun 2009 13:28:07 BST." <4A4A12E7020000690001710C@gwmail.jr2.ox.ac.uk> Message-ID: <20090630174437.23189BCEF@ip-64-139-1-69.sjc.megapath.net> > I am not very much interested in how it is achieved, but wonder if a > 10MHz oscillator locked to GPS is now available as "plug&play" rather > than needing a lot of time/effort/building. > I note the Thunderbolt units available from the Far East on ebay > for~?80gbp. Are these really P&P - that is, just connect PSU and > aerial and out comes 10MHz locked to GPS? Is it necessary to connect > to a computer via the RS232 link, or is that just there if you want to > fiddle and be clever? You probably need a PC to set it up. After that, it should just work all by itself. The problem is that the Thunderbolt doesn't have any LEDs to tell you that it is or isn't happy. The main thing you might want to monitor is the number of satellites. If your antenna is in a good location, that will get boring pretty quickly. If your antenna is marginal, you can watch it occasionally go into holdover when there aren't any satellites visible. If you like software, you could program your favorite one-chip micro to talk to the serial link and blink a LED when something is wrong. You can test the holdover stuff by disconnecting the antenna. > If so, then this may be preferrable to running my rubidium source > continuously. The rubidium doesn't need an antenna. For the price of a Thunderbolt, you could get a spare rubidium. (I'm assuming you are using Telco surplus units.) > What I am interested in is stability, not ultiamte accuracy. What level of stability do you need? What time scale? Is an OCXO good enough? The nice think about a GPSDO is the great long term stability. -- These are my opinions, not necessarily my employer's. I hate spam. From m0ycm at veenstras.com Tue Jun 30 18:17:31 2009 From: m0ycm at veenstras.com (Lester Veenstra) Date: Tue, 30 Jun 2009 19:17:31 +0100 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> Message-ID: I suggest you try The RF Connection for adapters: NM/FF N(M)/F(F) 3.00 http://therfc.com/ Lester B Veenstra M?YCM K1YCM lester at veenstras.com m0ycm at veenstras.com k1ycm at veenstras.com US Postal Address: PSC 45 Box 781 APO AE 09468 USA UK Postal Address: Dawn Cottage Norwood, Harrogate HG3 1SD, UK Telephones: Office: +44-(0)1423-846-385 Home: +44-(0)1943-880-963 Guam Cell: +1-671-788-5654 UK Cell: +44-(0)7716-298-224 US Cell: +1-240-425-7335 Jamaica: +1-876-352-7504 This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] ..n in two TNC to F adapters so I could go to ordinary RadioShack cable TV cable. I received two TNC to N instead. This cost me $5! No complaints, just a minor annoyance, but now I have a pair of adapters I didn't have before -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 2053 bytes Desc: not available URL: From jra at febo.com Tue Jun 30 18:40:16 2009 From: jra at febo.com (John Ackermann N8UR) Date: Tue, 30 Jun 2009 14:40:16 -0400 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> Message-ID: <4A4A5C10.4060808@febo.com> For really good adapters, I've had good luck with S.M. Electronics (http://www.smelectronicsllc.com). They are pricey -- like $24-$36 each for 18 GHz stainless N-to-something adapters, but I think on the whole cheaper than Pasternack, and they often stock several grades (with specified frequency for SWR) at different price points. I've been really happy with the quality, and they usually ship the same day. They also have a really wide variety of adapters available -- they can match just about anything to anything else. Their stuff is probably overkill for antenna cable adapters, but is great for use on test equipment. John ---- Lester Veenstra wrote: > I suggest you try The RF Connection for adapters: > > > NM/FF > N(M)/F(F) > 3.00 > > http://therfc.com/ > > Lester B Veenstra M?YCM K1YCM > lester at veenstras.com > m0ycm at veenstras.com > k1ycm at veenstras.com > > > US Postal Address: > PSC 45 Box 781 > APO AE 09468 USA > > UK Postal Address: > Dawn Cottage > Norwood, Harrogate > HG3 1SD, UK > > Telephones: > Office: +44-(0)1423-846-385 > Home: +44-(0)1943-880-963 > Guam Cell: +1-671-788-5654 > UK Cell: +44-(0)7716-298-224 > US Cell: +1-240-425-7335 > Jamaica: +1-876-352-7504 > > This e-mail and any documents attached hereto contain confidential or > privileged information. The information is intended to be for use only by > the individual or entity to whom they are addressed. If you are not the > intended recipient or the person responsible for delivering the e-mail to > the intended recipient, be aware that any disclosure, copying, distribution > or use of the contents of this e-mail or any documents attached hereto is > prohibited. > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] > ??..n in two TNC to F adapters so I could go to ordinary RadioShack cable TV > cable. I received two TNC to N instead. This cost me $5! No complaints, > just a minor annoyance, but now I have a pair of adapters I didn't have > before ???? > > > > ------------------------------------------------------------------------ > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From james.p.lux at jpl.nasa.gov Tue Jun 30 18:44:36 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 30 Jun 2009 11:44:36 -0700 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: <4A4A5C10.4060808@febo.com> References: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> <4A4A5C10.4060808@febo.com> Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of John Ackermann N8UR > Sent: Tuesday, June 30, 2009 11:40 AM > To: lester at veenstras.com; Discussion of precise time and > frequency measurement > Subject: Re: [time-nuts] Plug and play GPSDOs was:(no subject) > > For really good adapters, I've had good luck with S.M. > Electronics (http://www.smelectronicsllc.com). They are > pricey -- like $24-$36 each for 18 GHz stainless > N-to-something adapters, but I think on the whole cheaper > than Pasternack, and they often stock several grades (with > specified frequency for SWR) at different price points. > Likewise.. They're a good source for between series adapters and pads, particularly for microwave (e.g. K<>SMA or 2.4<>3.5) From rdarlington at gmail.com Tue Jun 30 18:51:28 2009 From: rdarlington at gmail.com (Robert Darlington) Date: Tue, 30 Jun 2009 12:51:28 -0600 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: <4A4A51B90200006900017119@gwmail.jr2.ox.ac.uk> Message-ID: eBay. 12 bucks for 4 including shipping :) -Bob On Tue, Jun 30, 2009 at 12:17 PM, Lester Veenstra wrote: > I suggest you try The RF Connection for adapters: > > > NM/FF > N(M)/F(F) > 3.00 > > http://therfc.com/ > > Lester B Veenstra M?YCM K1YCM > lester at veenstras.com > m0ycm at veenstras.com > k1ycm at veenstras.com > > > US Postal Address: > PSC 45 Box 781 > APO AE 09468 USA > > UK Postal Address: > Dawn Cottage > Norwood, Harrogate > HG3 1SD, UK > > Telephones: > Office: +44-(0)1423-846-385 > Home: +44-(0)1943-880-963 > Guam Cell: +1-671-788-5654 > UK Cell: +44-(0)7716-298-224 > US Cell: +1-240-425-7335 > Jamaica: +1-876-352-7504 > > This e-mail and any documents attached hereto contain confidential or > privileged information. The information is intended to be for use only by > the individual or entity to whom they are addressed. If you are not the > intended recipient or the person responsible for delivering the e-mail to > the intended recipient, be aware that any disclosure, copying, distribution > or use of the contents of this e-mail or any documents attached hereto is > prohibited. > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] > ??..n in two TNC to F adapters so I could go to ordinary RadioShack cable > TV > cable. I received two TNC to N instead. This cost me $5! No complaints, > just a minor annoyance, but now I have a pair of adapters I didn't have > before ???? > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > From g4hup at btinternet.com Tue Jun 30 20:58:41 2009 From: g4hup at btinternet.com (dave powis) Date: Tue, 30 Jun 2009 20:58:41 +0000 (GMT) Subject: [time-nuts] (no subject) In-Reply-To: <4A4A12E7020000690001710C@gwmail.jr2.ox.ac.uk> References: <4A4A12E7020000690001710C@gwmail.jr2.ox.ac.uk> Message-ID: <332312.56078.qm@web86309.mail.ird.yahoo.com> Hi David, I don't know the Chinese ones, but I was lucky enough to get one of the TAPR offer TBolts - and it really was P&P - yes, I attached a PC and used the TBolt monitoring utility to confirm it was all working OK, but that was all. It now sits in my shack outputing 10MHz very nicely. 73, Dave ________________________________ From: David Hilton-Jones To: time-nuts at febo.com Sent: Tuesday, 30 June, 2009 1:28:07 PM Subject: [time-nuts] (no subject) I am not very much interested in how it is achieved, but wonder if a 10MHz oscillator locked to GPS is now available as "plug&play" rather than needing a lot of time/effort/building. I note the Thunderbolt units available from the Far East on ebay for~?80gbp. Are these really P&P - that is, just connect PSU and aerial and out comes 10MHz locked to GPS? Is it necessary to connect to a computer via the RS232 link, or is that just there if you want to fiddle and be clever? If so, then this may be preferrable to running my rubidium source continuously. What I am interested in is stability, not ultiamte accuracy. As always, sorry for the naivety of the question. Thanks David, G4YTL _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From bg at lysator.liu.se Tue Jun 30 21:23:44 2009 From: bg at lysator.liu.se (bg at lysator.liu.se) Date: Tue, 30 Jun 2009 23:23:44 +0200 (CEST) Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: Message-ID: <60277.87.227.52.225.1246397024.squirrel@webmail.lysator.liu.se> > > There is one thing that make most GPSDOs not quite plug and play... that > is their need to know their location rather precisely. Yes, it's helpful on the way to perfection. Is it a requirement for the OPs level of ambition? I think not. I wonder if the long self-survey procedure is an artifact from the bad old SA-days, when there was a genuine need to filter out the quarter of an hour wiggle introduced to the GPS signals. -- Bj?rn From holrum at hotmail.com Tue Jun 30 21:32:23 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 30 Jun 2009 21:32:23 +0000 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: Message-ID: Yes, you can just leave the unit running without much problem, but what works really well is to use an old laptop as a permanent monitoring device. You can get them for around 20 bucks... Lady Heather was created for Thunderbolt just such a situation. Much more entertaining and informative than das blinkenlights. There are DOS and Windows versions available in the download at: http://www.thegleam.com/ke5fx/heather/readme.htm The Chinese suppliers seem to do quite well. Fluke.l has a good rep. I have also bought from flyingbest without any problem (but I have had problems getting responses to emails). The TAPR units (when available) have the distinct advantage of having Tom Van Baak give them the evil eye once over before being shipped. ---------------------------------------- I was thinking of setting up in a fixed position and leaving on permanently. But then if there's a power cut? Do you know if the China supplier is OK? Or any source in the UK of Thunderbolt? _________________________________________________________________ Lauren found her dream laptop. Find the PC that?s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 From james.p.lux at jpl.nasa.gov Tue Jun 30 21:38:04 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 30 Jun 2009 14:38:04 -0700 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Mark Sims > Sent: Tuesday, June 30, 2009 2:32 PM > To: time-nuts at febo.com > Subject: [time-nuts] Plug and play GPSDOs was:(no subject) > > > Yes, you can just leave the unit running without much > problem, but what works really well is to use an old laptop > as a permanent monitoring device. You can get them for > around 20 bucks... Lady Heather was created for Thunderbolt > just such a situation. Much more entertaining and > informative than das blinkenlights. There are DOS and > Windows versions available in the download at: > > http://www.thegleam.com/ke5fx/heather/readme.htm > > Even better would be some ambitious amateur programming one of the little LCD+microcontroller widgets to make a display. Probably not worth it, dollar wise, but might be nice, especially for a field operation (e.g. setting up a hilltopping microwave setup or something like that.. Minimize the number of separate boxes, etc.) From holrum at hotmail.com Tue Jun 30 21:44:05 2009 From: holrum at hotmail.com (Mark Sims) Date: Tue, 30 Jun 2009 21:44:05 +0000 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: Message-ID: The main reason for manually doing the self-survey and saving the results is so that the unit won't spend hours doing it every time it powers up. It's a one time thing and well worth the trouble. Every foot of position error can introduce a nanosecond of offset in the timing results. Probably not an issue for most people. However, it can also introduce some offsets in the frequency output (which is what most people buy these things for). The frequency offsets tend to average out over a day, but these units are capable of producing cesium-beam quality output for a zillionth the price (and over extended periods of time they will beat a cesium oscillator). You might was well give them as good a quality head start as you can... ---------------------------------------- Yes, it's helpful on the way to perfection. Is it a requirement for the OPs level of ambition? I think not. I wonder if the long self-survey procedure is an artifact from the bad old SA-days, when there was a genuine need to filter out the quarter of an hour wiggle introduced to the GPS signals. _________________________________________________________________ Insert movie times and more without leaving Hotmail?. http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tutorial_QuickAdd_062009 From GandalfG8 at aol.com Tue Jun 30 21:48:14 2009 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 30 Jun 2009 17:48:14 EDT Subject: [time-nuts] Plug and play GPSDOs was:(no subject) Message-ID: In a message dated 30/06/2009 22:38:35 GMT Daylight Time, james.p.lux at jpl.nasa.gov writes: Even better would be some ambitious amateur programming one of the little LCD+microcontroller widgets to make a display. Probably not worth it, dollar wise, but might be nice, especially for a field operation (e.g. setting up a hilltopping microwave setup or something like that.. Minimize the number of separate boxes, etc.) --------- Something like this by any chance?:-).......... _http://www.ko4bb.com/Timing/GPSMonitor/_ (http://www.ko4bb.com/Timing/GPSMonitor/) regards Nigel GM8PZR From james.p.lux at jpl.nasa.gov Tue Jun 30 21:54:54 2009 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Tue, 30 Jun 2009 14:54:54 -0700 Subject: [time-nuts] Plug and play GPSDOs was:(no subject) In-Reply-To: References: Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of GandalfG8 at aol.com > Sent: Tuesday, June 30, 2009 2:48 PM > To: time-nuts at febo.com > Subject: Re: [time-nuts] Plug and play GPSDOs was:(no subject) > > --------- > Something like this by any chance?:-).......... > > _http://www.ko4bb.com/Timing/GPSMonitor/_ > (http://www.ko4bb.com/Timing/GPSMonitor/) > > regards > Yes.. Except the "work-in-progress, hard hat required" part And then I was thinking about something where you hook a bluetooth serial port dongle on the thunderbolt (or other RS232 device), and then use your PDA/iPhone/etc as the display/control interface. From kmalcolm at tpg.com.au Tue Jun 30 22:59:52 2009 From: kmalcolm at tpg.com.au (Keith G Malcolm) Date: Wed, 01 Jul 2009 08:59:52 +1000 Subject: [time-nuts] Thunderbolt plug and play In-Reply-To: References: Message-ID: <200906302300.n5UN0WWU032386@mail7.tpg.com.au> Hello David, I'm a complete beginner in this field, but after a lot of reading and following these threads, I finally bought a Tbolt from China via e-bay. Arrived in just under a week by post, plugged it in to power and antenna and got 10 MHz output. I eventually connected a lap-top PC via a USB-serial adaptor cable, ran Tboltmon (downloadable from the Trimble site) (took longer to find which COM port the thing was using) and got a nice display. The unit was still showing its previous location as reference, so I just used Tboltmon to reset to my location using the position data shown by the Tbolt. Couldn't have been easier. I got mine from seller nhbbobb. Regards. Keith G Malcolm VK1KM At 03:44 AM 1/07/2009, time-nuts-request at febo.com wrote: >Message: 1 >Date: Tue, 30 Jun 2009 13:28:07 +0100 >From: "David Hilton-Jones" >Subject: [time-nuts] (no subject) >To: >Message-ID: <4A4A12E7020000690001710C at gwmail.jr2.ox.ac.uk> >Content-Type: text/plain; charset=UTF-8 > >I am not very much interested in how it is achieved, but wonder if a >10MHz oscillator locked to GPS is now available as "plug&play" rather >than needing a lot of time/effort/building. > >I note the Thunderbolt units available from the Far East on ebay >for~?80gbp. Are these really P&P - that is, just connect PSU and >aerial and out comes 10MHz locked to GPS? Is it necessary to connect to >a computer via the RS232 link, or is that just there if you want to >fiddle and be clever? > >If so, then this may be preferrable to running my rubidium source >continuously. > >What I am interested in is stability, not ultiamte accuracy. > >As always, sorry for the naivety of the question. > >Thanks > > >David, G4YTL