From jmiles at pop.net Fri Aug 1 00:40:29 2008 From: jmiles at pop.net (John Miles) Date: Thu, 31 Jul 2008 21:40:29 -0700 Subject: [time-nuts] What is a Time-Nut grade Zero Crossing Circuit? In-Reply-To: <22592.192.25.142.225.1217552351.squirrel@webmail.sonic.net> Message-ID: > > Modern ECL parts aren't necessarily that bad compared to the old MECL > > stuff. > > My experience goes all the way back to the MECL 1000 series that was > discontinued 30 years ago. I designed many synthesizers around them > for Zeta Labs. Every newer family of ECL line receivers has been faster > and had worse phase noise, in my experience. Which is odd because the jitter specs have gotten better -- at least, going by the promises and hype in the data sheets. It sounds like the newer ECL parts' wider bandwidth is folding more noise into the output signal. > This is a very tricky topic. When measuring the phase noise of a non > sine wave, there are dependencies on how the measurement is done. > What is the measurement bandwidth? Etc. > > In some cases, the noise is mostly common mode, and therefore will > depend on the common mode rejection ratio (if any) of your measurement > circuit. I'm measuring it with a 3048A, feeding the DBM directly from one of the MC100EL16P's output pins via a 0.1 uF cap. Both output pins are tied to ground with 200 ohms, per Q12 at http://www.pulseresearchlab.com/faqs/ecl_ques/ecl_Q9-Q12.htm . Input-wise, I just tried a T1-1 balun instead of the single-ended termination I was using before, and got exactly the same results (floor at circa -148 to -150 dBc/Hz at 100 MHz, but only -140 dBc/Hz at 10 MHz.) That, I thought was interesting. -148 dBc/Hz was always the 'rule of thumb' for the older ECL families from what I've read, and since it's not sensitive to input configuration or power-supply bypassing, it must be the process floor. There was no LC or other bandpass filtering at the input, but the sources are decent-quality OCXOs in both cases so I don't think I'm feeding it too much broadband noise to begin with. Maybe another T1-1 at the output would help, but I don't see any reason to think so. -- john, KE5FX From richard at karlquist.com Fri Aug 1 01:05:43 2008 From: richard at karlquist.com (Richard (Rick) Karlquist) Date: Thu, 31 Jul 2008 22:05:43 -0700 Subject: [time-nuts] What is a Time-Nut grade Zero Crossing Circuit? In-Reply-To: References: Message-ID: <489299A7.5020903@karlquist.com> John Miles wrote: >>> Modern ECL parts aren't necessarily that bad compared to the old MECL >>> stuff. >> My experience goes all the way back to the MECL 1000 series that was >> discontinued 30 years ago. I designed many synthesizers around them >> for Zeta Labs. Every newer family of ECL line receivers has been faster >> and had worse phase noise, in my experience. > > Which is odd because the jitter specs have gotten better -- at least, going > by the promises and hype in the data sheets. It sounds like the newer ECL > parts' wider bandwidth is folding more noise into the output signal. The older parts had no jitter specs. Jitter specs assume a logic waveform input, not a sine wave input. Many jitter specs refer to pattern jitter of data, which does not apply to clocks. Also, jitter increases at low frequencies in practice, even though in theory it should not. Like I said, this topic is very tricky. Rick Karlquist N6RK > >> This is a very tricky topic. When measuring the phase noise of a non >> sine wave, there are dependencies on how the measurement is done. >> What is the measurement bandwidth? Etc. >> >> In some cases, the noise is mostly common mode, and therefore will >> depend on the common mode rejection ratio (if any) of your measurement >> circuit. > > I'm measuring it with a 3048A, feeding the DBM directly from one of the > MC100EL16P's output pins via a 0.1 uF cap. Both output pins are tied to > ground with 200 ohms, per Q12 at > http://www.pulseresearchlab.com/faqs/ecl_ques/ecl_Q9-Q12.htm . > > Input-wise, I just tried a T1-1 balun instead of the single-ended > termination I was using before, and got exactly the same results (floor at > circa -148 to -150 dBc/Hz at 100 MHz, but only -140 dBc/Hz at 10 MHz.) > That, I thought was interesting. -148 dBc/Hz was always the 'rule of thumb' > for the older ECL families from what I've read, and since it's not sensitive > to input configuration or power-supply bypassing, it must be the process > floor. I measured phase noise on an MC100E131 drop from -145 to -165 by taking the output differentially. This was done in 1992. Others have been unable to repeat this result, even using some old 1992 parts I kept. So who knows? Todd Pearson of Motorola said that they have seen this drop with differential outputs. > > There was no LC or other bandpass filtering at the input, but the sources > are decent-quality OCXOs in both cases so I don't think I'm feeding it too > much broadband noise to begin with. > > Maybe another T1-1 at the output would help, but I don't see any reason to > think so. > > -- 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 bob.paddock at gmail.com Fri Aug 1 06:32:04 2008 From: bob.paddock at gmail.com (Bob Paddock) Date: Fri, 1 Aug 2008 06:32:04 -0400 Subject: [time-nuts] What is a Time-Nut grade Zero Crossing Circuit? In-Reply-To: <489299A7.5020903@karlquist.com> References: <489299A7.5020903@karlquist.com> Message-ID: > Jitter specs assume a logic > waveform input, not a sine wave input. Many jitter specs refer to > pattern jitter of data, which does not apply to clocks. Also, jitter > increases at low frequencies in practice, even though in theory it > should not. Like I said, this topic is very tricky. How exactly does zero jitter? I understand that the logic detecting the zero voltage point of a sine wave might not be perfect. However if the circuit is truly a Zero Crossing Detector, things like the frequency and amplitude variations of the sine wave are irrelevant, as long as the bandwidth is sufficient to the design of the detector. From bruce.griffiths at xtra.co.nz Fri Aug 1 06:57:50 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 01 Aug 2008 22:57:50 +1200 Subject: [time-nuts] What is a Time-Nut grade Zero Crossing Circuit? In-Reply-To: References: <489299A7.5020903@karlquist.com> Message-ID: <4892EC2E.1040903@xtra.co.nz> Bob Paddock wrote: >> Jitter specs assume a logic >> waveform input, not a sine wave input. Many jitter specs refer to >> pattern jitter of data, which does not apply to clocks. Also, jitter >> increases at low frequencies in practice, even though in theory it >> should not. Like I said, this topic is very tricky. >> > > How exactly does zero jitter? I understand that the logic detecting > the zero voltage point of a sine wave might not be perfect. However > if the circuit is truly a Zero Crossing Detector, things like > the frequency and amplitude variations of the sine wave are irrelevant, > as long as the bandwidth is sufficient to the design of the detector. > > Real circuits have noise. Thus with a signal having a finite slew rate through the zero crossing any noise (internal or external) will cause the switching delay (from the noise free zero crossing) to differ for each zero crossing. The noise increases with circuit bandwidth increasing the noise. There is an optimum bandwidth which minimises the ratio of the noise to zero crossing slew rate and hence the jitter. Smaller or larger bandwidths increase the jitter. Sinewave amplitude variations alter the zero crossing slew rate and hence the jitter. There is a minimum input slew rate required to minimise the jitter at the output of a logic gate. When the zero crossing slew rate is less than this a slope amplifier consisting of a cascade of amplifier limiters each with a filtered output is used to amplify the slope. The gain and filter bandwidth for each stage are optimised to meet the required slope gain whilst minimising the output noise. There is also an optimum number of gain stages for minimum noise. Bruce From frankmarian at optusnet.com.au Sat Aug 2 04:48:07 2008 From: frankmarian at optusnet.com.au (frankmarian) Date: Sat, 2 Aug 2008 18:48:07 +1000 Subject: [time-nuts] PCB for frequency divider Message-ID: Hi Dave If you have any boards still available I would like to purchase one please. I live in Australia. Could you please send circuit diagram please Regards Frank From magnus at rubidium.dyndns.org Sat Aug 2 12:44:57 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 02 Aug 2008 18:44:57 +0200 Subject: [time-nuts] How to get 32.768KHz from 10MHz. In-Reply-To: <00b901c8eccd$b95782b0$7300a8c0@p4253> References: <00b901c8eccd$b95782b0$7300a8c0@p4253> Message-ID: <48948F09.9090803@rubidium.dyndns.org> Max Skop wrote: > How does one get a 32.768KHz signal from our 10MHz reference. > There does not appear to be a nice divide ratio to do this. > With a locked 32.768KHz signal one could lock the oscillator of any of the cheap (low cost) LCD clocks that are available with nice big digits, temperature sensors and calendars, etc. > Any suggestions on how to do it?? I would consider locking a 8,192 MHz crystal to the 10 MHz. The comparator frequency of 16 kHz using a division of 625 from the 10 MHz and a 512 from the 8,192 MHz oscillator. The 32,768 kHz output can be generated by first dividing by 125 and then a division by 2 for propper 50% pulse ratio. Not too complex and the comparator frequency is high enought for a nice filter should be able to do it. I would use a SR flip-flop for phase detector. For this kind of work they work very well IMHO. Cheers, Magnus From not.again at btinternet.com Sat Aug 2 16:38:14 2008 From: not.again at btinternet.com (Angus) Date: Sat, 02 Aug 2008 21:38:14 +0100 Subject: [time-nuts] LPRO 101 ADJUSTMENT In-Reply-To: <1AC9FBE457064A31938866B12D0E56F8@DESKTOP> References: <9835219326F6421AB4A20EA07D3471FD@athlon> <48876375.5060200@tiscali.co.uk> <05B23324048C4866A8B94C37A6E6BDD1@DESKTOP> <488A5E7A.6060602@intt.net> <1AC9FBE457064A31938866B12D0E56F8@DESKTOP> Message-ID: External adjustment makes it very easy to adjust as you have access to the adjustment voltage to measure it, and even a 1K multi-turn wirewound pot would give around 1E-12 setting resolution. The sensitivty of the EFC is only around 1E-12 per mV, so it is much less sensitive to temperature stability than quartz oscillators. A temperature coeff of +/- 20ppm /degC with an EFC voltage of 2.5V would only contribute around +/-5E-14 /degC frequency change. By adding fine adjustment or a DAC, you can get way below 1E-13 setting resolution. The only problem here is that environmental conditions such as variations in temperature and pressure do affect Rb oscillators and the EFC circuit, and can change the frequency by 1E-13 in a matter of minutes. Still, it's useful to be able to do it for disciplining, or if the environmental conditions are being controlled or compensated for. The ADEV of an LPRO can be around 1E-13 or so at a tau of hours, so even a step size of 1E-13 can be rather too coarse, especially if the environmental effects have been minimised. It would be nice to find a relatively simple and inexpensive 10MHz synthesizer that has a resolution of closer to 1E-14 to avoid messing with the EFC at all. Angus. On Fri, 25 Jul 2008 20:33:26 -0400, you wrote: >If I choose to control the frequency via External C-field control I guess it >would take a very precise and stable voltage source. Any thoughts or >suggestions? > >----- Original Message ----- >From: "Scott Mace" >To: "jshank" ; "Discussion of precise time and >frequency measurement" >Sent: Friday, July 25, 2008 7:15 PM >Subject: Re: [time-nuts] LPRO 101 ADJUSTMENT > > >> Both methods work well. Be sure the unit is mounted to some sort of >> heatsink,chassis, etc. >> I'm using a Fury GPS receiver to drive the EFC on an LPRO-101. >> You won't get much range out of either adjustment. Leave it powered >> on for a couple of hours before trying to adjust it. I usually set the >> trim pot in the >> middle of it's range and use the EFC pin. I think it's a 28 or 30 turn >> pot. EFC >> is 0-5v. The unit will self-bias to around 2.5v if the EFC pin is open. >> >> Scott >> >> jshank wrote: >>> Hi, >>> >>> I recently acquired a LPRO 101 Rubidium Oscillator. After reading the >>> manual I see that there are two ways to adjust the frequency 1) using and >>> adjusting screw on the unit and 2) using the External C-field control >>> signal at pin J1-7. Has anyone experimented with either method and if so >>> what method was preferred? >>> >>> Jeff >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- 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 mfeher at eozinc.com Sat Aug 2 18:59:09 2008 From: mfeher at eozinc.com (Mike Feher) Date: Sat, 2 Aug 2008 18:59:09 -0400 Subject: [time-nuts] Antikythera In-Reply-To: References: Message-ID: <013501c8f4f3$609c5eb0$0201a8c0@gsmacdq14es> FYI - Mike http://www.nature.com/nature/videoarchive/antikythera/ Mike B. Feher, N4FS 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 From rogburn at warpspeed1.net Sun Aug 3 09:48:19 2008 From: rogburn at warpspeed1.net (Robert Ogburn) Date: Sun, 3 Aug 2008 08:48:19 -0500 Subject: [time-nuts] Trimble Placer GPS400 Message-ID: We have a Trimble Placer GPS400 that reports version as: SVEESIX ver 4.06 (05/18/94) core ver 1.17 (12/21/93). Is this correct? If not, how do we restore? Thanks bob From rk at timing-consultants.com Mon Aug 4 04:03:10 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Mon, 4 Aug 2008 09:03:10 +0100 Subject: [time-nuts] Trimble Placer GPS400 In-Reply-To: References: Message-ID: Bob, SVEESIX is a Trimble GPS engine. From the report, it is telling you that the model you have uses that engine with those version numbers. What are you looking to restore? Not sure I understand your problem. Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Ogburn Sent: 03 August 2008 14:48 To: time-nuts at febo.com Subject: [time-nuts] Trimble Placer GPS400 We have a Trimble Placer GPS400 that reports version as: SVEESIX ver 4.06 (05/18/94) core ver 1.17 (12/21/93). Is this correct? If not, how do we restore? Thanks bob _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. From vilgotch at bigpond.net.au Mon Aug 4 04:48:27 2008 From: vilgotch at bigpond.net.au (Morris Odell) Date: Mon, 4 Aug 2008 18:48:27 +1000 Subject: [time-nuts] Antikythera References: Message-ID: <003c01c8f60e$dd2b0be0$ad00a8c0@Morris1> ----- Original Message ----- > Date: Sat, 2 Aug 2008 18:59:09 -0400 > From: "Mike Feher" > Subject: [time-nuts] Antikythera > To: "'Discussion of precise time and frequency measurement'" > > Message-ID: <013501c8f4f3$609c5eb0$0201a8c0 at gsmacdq14es> > Content-Type: text/plain; charset="US-ASCII" > > FYI - Mike > > http://www.nature.com/nature/videoarchive/antikythera/ > See: http://www.tatjavanvark.nl/antikythera/index.html and take a look at the rest of her website as well! Morris From jim77742 at gmail.com Mon Aug 4 05:47:16 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Mon, 4 Aug 2008 19:47:16 +1000 Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser Message-ID: Hi folks, I took my recently acquired Thunderbolt, along with my 5370B, to the observatory on the weekend and plotted its residual against the NR Active Hydrogen Maser. See the attached graph (ignore the "line of best fit" heading - 0.00 was simply the starting point). Note that I didn't let the Thunderbolt do a survey, I simply plugged in the local GPS coordinates which I later verified were about 5m to the east of the actual Thunderbolt antenna. The y axis is residual in nanoseconds and the x axis is Modified Julian Date. I find the residuals fascinating. Note the identical repeating residuals in a 24 hour cycle. Is this due to thermal or constellation issues? The local GPS (not a GPSDO but an early version Totally Accurate Clock) showed a roughly (very roughly) similar pattern when averaged with 5 minute averages to hide the awful 100nsec sawtooth. The observatory is air conditioned (but with poor insulation) and has many devices constantly running. I doubt it is thermal, however the low point is at 6:30am in the morning, just before I arrived. Can anyone provide comment on this pattern? Regards, Jim -------------- next part -------------- A non-text attachment was scrubbed... Name: ThunderboltHM.JPG Type: image/jpeg Size: 61085 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080804/689bbb91/attachment-0001.jpeg From phk at phk.freebsd.dk Mon Aug 4 06:36:30 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Mon, 04 Aug 2008 10:36:30 +0000 Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser In-Reply-To: Your message of "Mon, 04 Aug 2008 19:47:16 +1000." Message-ID: <1636.1217846190@critter.freebsd.dk> In message , "Jim Palfreyman" writes: >I find the residuals fascinating. Note the identical repeating residuals in >a 24 hour cycle. > >Is this due to thermal or constellation issues? That is almost 100% guaranteed to be constellation issues. Notice that 5m antenna offset is 15 nanolightseconds. -- 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 bg at lysator.liu.se Mon Aug 4 10:34:48 2008 From: bg at lysator.liu.se (=?ISO-8859-1?Q?Bj=F6rn?= Gabrielsson) Date: Mon, 04 Aug 2008 16:34:48 +0200 Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser In-Reply-To: <1636.1217846190@critter.freebsd.dk> References: <1636.1217846190@critter.freebsd.dk> Message-ID: <1217860488.7397.49.camel@bg-desktop> On Mon, 2008-08-04 at 10:36 +0000, Poul-Henning Kamp wrote: > In message , "Jim > Palfreyman" writes: > > >I find the residuals fascinating. Note the identical repeating residuals in > >a 24 hour cycle. > > > >Is this due to thermal or constellation issues? > > That is almost 100% guaranteed to be constellation issues. My vote is on antenna multipath. -- Bj?rn From tom.k3io at gmail.com Tue Aug 5 01:08:10 2008 From: tom.k3io at gmail.com (Tom Clark, K3IO) Date: Tue, 05 Aug 2008 01:08:10 -0400 Subject: [time-nuts] time-nuts Digest, Vol 49, Issue 4 In-Reply-To: References: Message-ID: <4897E03A.5090508@verizon.net> Jim Palfreyman noted I took my recently acquired Thunderbolt, along with my 5370B, to the observatory on the weekend and plotted its residual against the NR Active Hydrogen Maser. See the attached graph (ignore the "line of best fit" heading - 0.00 was simply the starting point). Note that I didn't let the Thunderbolt do a survey, I simply plugged in the local GPS coordinates which I later verified were about 5m to the east of the actual Thunderbolt antenna. The y axis is residual in nanoseconds and the x axis is Modified Julian Date. I find the residuals fascinating. Note the identical repeating residuals in a 24 hour cycle. Is this due to thermal or constellation issues? The local GPS (not a GPSDO but an early version Totally Accurate Clock) showed a roughly (very roughly) similar pattern when averaged with 5 minute averages to hide the awful 100nsec sawtooth. Not at all unexpected. I recommend you look at 3 papers on our archive at [1]http://gpstime.com/: In "Low-cost, High Accuracy GPS Timing" you will see the state-of-the-art circa 2000. In slide 16 you see the same type of diurnal bumps, which are due to the residual ionosphere. The GPS satellite broadcast message contains a gross ionospheric correction number based on sunspot count and 2.7 GHz solar flux. But the typical single-frequency receiver has ZERO correction for a day-night ionospheric cycle. At the GPS frequency (1575.42 MHz) the total effect of the ionosphere in the zenith is about 5 meters; the effect at lower elevation angles is even more -- say 7 meters or so. And the day-night variation (max late afternoon local time so GPS runs slow, min early morning so GPS is fast) typically is in the range of 5 meters = 15 nsec or so. In "Critical Evaluation of the Motorola M12+ ..." take a look at Figure 7 (in the PDF) or slides 17/18 (in PPT). You will see the diurnal ionosphere causing ~10-20 nsec of variability and even a 50 nsec excursion due to a large solar "incident". The 2007 version of my "Timing for VLBI " tutorial shows some more modern data, including a description of what causes the "awful sawtooth" and how it can be removed in hardware. FYI -- the 100 nsec sawtooth you see was characteristic of the early 6- and 8-channel Motorola Oncore receivers that I used in my original TACs and Rick used in the first generation of CNS Clocks. When Motorola brought out their new M12-series, the magnitude dropped to ~24 nsec. And it could always be removed in software (even with the older receivers); a binary message from the receiver tells the user the size of the error (quantized in 1 nsec steps) of the next 1PPS tick. Rick's TAC32 software can log the corrected 1PPS value from a low-cost (HP53131/132) counter, so the "ugly sawtooth" is never a problem. Of course. averaging over tens of minutes wipes out the effect too -- just look at the 1995 results from Onsala in the papers. Regards, Tom References 1. http://gpstime.com/ From rk at timing-consultants.com Tue Aug 5 03:26:16 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Tue, 5 Aug 2008 08:26:16 +0100 Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser In-Reply-To: References: Message-ID: <0DF05B40E876451F82670FEE4D99EC8A@Robin> I'm pretty certain that this due to position error. You state that you have a 5m error in position. 5m equates to approximately 15nS. Having seen similar results before from positional errors it would be good idea to let the unit self survey and then run the tests again. Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Jim Palfreyman Sent: 04 August 2008 10:47 To: time-nuts at febo.com Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser Hi folks, I took my recently acquired Thunderbolt, along with my 5370B, to the observatory on the weekend and plotted its residual against the NR Active Hydrogen Maser. See the attached graph (ignore the "line of best fit" heading - 0.00 was simply the starting point). Note that I didn't let the Thunderbolt do a survey, I simply plugged in the local GPS coordinates which I later verified were about 5m to the east of the actual Thunderbolt antenna. The y axis is residual in nanoseconds and the x axis is Modified Julian Date. I find the residuals fascinating. Note the identical repeating residuals in a 24 hour cycle. Is this due to thermal or constellation issues? The local GPS (not a GPSDO but an early version Totally Accurate Clock) showed a roughly (very roughly) similar pattern when averaged with 5 minute averages to hide the awful 100nsec sawtooth. The observatory is air conditioned (but with poor insulation) and has many devices constantly running. I doubt it is thermal, however the low point is at 6:30am in the morning, just before I arrived. Can anyone provide comment on this pattern? Regards, Jim From jim77742 at gmail.com Tue Aug 5 05:55:27 2008 From: jim77742 at gmail.com (jim77742 at gmail.com) Date: Tue, 5 Aug 2008 19:55:27 +1000 Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser In-Reply-To: <0DF05B40E876451F82670FEE4D99EC8A@Robin> References: <0DF05B40E876451F82670FEE4D99EC8A@Robin> Message-ID: So why did the Totally Accurate Clock show the same pattern? On 05/08/2008, Rob Kimberley wrote: > I'm pretty certain that this due to position error. You state that you have > a 5m error in position. 5m equates to approximately 15nS. > > Having seen similar results before from positional errors it would be good > idea to let the unit self survey and then run the tests again. > > Rob Kimberley > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of Jim Palfreyman > Sent: 04 August 2008 10:47 > To: time-nuts at febo.com > Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser > > Hi folks, > > I took my recently acquired Thunderbolt, along with my 5370B, to the > observatory on the weekend and plotted its residual against the NR Active > Hydrogen Maser. See the attached graph (ignore the "line of best fit" > heading - 0.00 was simply the starting point). > > Note that I didn't let the Thunderbolt do a survey, I simply plugged in the > local GPS coordinates which I later verified were about 5m to the east of > the actual Thunderbolt antenna. > > The y axis is residual in nanoseconds and the x axis is Modified Julian > Date. > > I find the residuals fascinating. Note the identical repeating residuals in > a 24 hour cycle. > > Is this due to thermal or constellation issues? > > The local GPS (not a GPSDO but an early version Totally Accurate Clock) > showed a roughly (very roughly) similar pattern when averaged with 5 minute > averages to hide the awful 100nsec sawtooth. > > The observatory is air conditioned (but with poor insulation) and has many > devices constantly running. I doubt it is thermal, however the low point is > at 6:30am in the morning, just before I arrived. > > Can anyone provide comment on this pattern? > > Regards, > > Jim > > > _______________________________________________ > time-nuts mailing list -- 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 rk at timing-consultants.com Tue Aug 5 06:11:45 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Tue, 5 Aug 2008 11:11:45 +0100 Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser In-Reply-To: References: <0DF05B40E876451F82670FEE4D99EC8A@Robin> Message-ID: <0951A102E38A4868A146F4C42C30BE0C@Robin> Good point. How was the position of the so called "Totally Accurate Clock" obtained. Strange name though - no such thing as a totally accurate clock... :-) Rob -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of jim77742 at gmail.com Sent: 05 August 2008 10:55 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt v Active Hydrogen Maser So why did the Totally Accurate Clock show the same pattern? On 05/08/2008, Rob Kimberley wrote: > I'm pretty certain that this due to position error. You state that you > have a 5m error in position. 5m equates to approximately 15nS. > > Having seen similar results before from positional errors it would be > good idea to let the unit self survey and then run the tests again. > > Rob Kimberley > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] > On Behalf Of Jim Palfreyman > Sent: 04 August 2008 10:47 > To: time-nuts at febo.com > Subject: [time-nuts] Thunderbolt v Active Hydrogen Maser > > Hi folks, > > I took my recently acquired Thunderbolt, along with my 5370B, to the > observatory on the weekend and plotted its residual against the NR > Active Hydrogen Maser. See the attached graph (ignore the "line of best fit" > heading - 0.00 was simply the starting point). > > Note that I didn't let the Thunderbolt do a survey, I simply plugged > in the local GPS coordinates which I later verified were about 5m to > the east of the actual Thunderbolt antenna. > > The y axis is residual in nanoseconds and the x axis is Modified > Julian Date. > > I find the residuals fascinating. Note the identical repeating > residuals in a 24 hour cycle. > > Is this due to thermal or constellation issues? > > The local GPS (not a GPSDO but an early version Totally Accurate > Clock) showed a roughly (very roughly) similar pattern when averaged > with 5 minute averages to hide the awful 100nsec sawtooth. > > The observatory is air conditioned (but with poor insulation) and has > many devices constantly running. I doubt it is thermal, however the > low point is at 6:30am in the morning, just before I arrived. > > Can anyone provide comment on this pattern? > > Regards, > > Jim > > > _______________________________________________ > time-nuts mailing list -- 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 mensa999 at aol.com Tue Aug 5 11:30:55 2008 From: mensa999 at aol.com (MENSA999) Date: Tue, 5 Aug 2008 11:30:55 -0400 Subject: [time-nuts] TrueTime XL-DC Problems Message-ID: This is a long shot but I am hoping that someone might be able to give me some Hints as to a problem that I am having with a Used 151-601 XL-DC Receiver that I recently purchased. When I first fired it up it showed a date of 1990 so I updated the Date to the current one and then went through a 24 hour Auto Mode set up. Once the receiver went into Time mode at the end of set up. I pushed the Location button and noted A good Lat, Lon and elevation had been established. The LCD was showing 3D for the most part and 5 or 6 SAT PRN's. Looking at Osc Stats I see Offsets ranging from the 10 -10 to 10 -12, Drift 10-08 to 10-09, Phase 10-08 to 10-10 and DAC ranging very slowly from 15950 up to 16400 or so. Now the bad news after days of operation I am still showing GPS Unlocked, Position, Time Unknown (Even though a Lat, Lon had been established and UTC had been added through a Function command), Time Error and Acquisition Error ; when I do a F73 "Show Faults" . I seem to be acquiring the satellites but not decoding their full message. I am not sure if this is due to a mistake I am making or a receiver failure. Any suggestions that anyone can give would be ever so greatly appreciated for I am at a loss and so far my web searches have been fruitless. Thank you all for your consideration in this..... Herb Belin Mensa999 at aol.com or 413 530 0048 From mensa999 at aol.com Tue Aug 5 11:51:20 2008 From: mensa999 at aol.com (MENSA999) Date: Tue, 5 Aug 2008 11:51:20 -0400 Subject: [time-nuts] Truetime XL-DC Problems "2nd try" Message-ID: <439d0694.7a9c.4958.9667.09bf9906ad9d@aol.com> This is a long shot but I am hoping that someone might be able to give me some Hints as to a problem that I am having with a Used 151-601 XL-DC Receiver that I recently purchased. When I first fired it up it showed a date of 1990 so I updated the Date to the current one and then went through a 24 hour Auto Mode set up. Once the receiver went into Time mode at the end of set up. I pushed the Location button and noted A good Lat, Lon and elevation had been established. The LCD was showing 3D for the most part and 5 or 6 SAT PRN's. Looking at Osc Stats I see Offsets ranging from the 10 -10 to 10 -12, Drift 10-08 to 10-09, Phase 10-08 to 10-10 and DAC ranging very slowly from 15950 up to 16400 or so. Now the bad news after days of operation I am still showing GPS Unlocked, Position, Time Unknown (Even though a Lat, Lon had been established and UTC had been added through a Function command), Time Error and Acquisition Error ; when I do a F73 "Show Faults" . I seem to be acquiring the satellites but not decoding their full message. I am not sure if this is due to a mistake I am making or a receiver failure. Any suggestions that anyone can give would be ever so greatly appreciated for I am at a loss and so far my web searches have been fruitless. Thank you all for your consideration in this..... Herb Belin Mensa999 at aol.com or 413 530 0048 From w4oa at vibroplex.com Tue Aug 5 12:23:46 2008 From: w4oa at vibroplex.com (F Mitchell) Date: Tue, 5 Aug 2008 11:23:46 -0500 Subject: [time-nuts] Power supply for Thunderbolt Message-ID: Anyone have a suggestion for a power supply for the Thunderbolt? Thanks Mitch W4OA From w1ksz at earthlink.net Tue Aug 5 12:29:13 2008 From: w1ksz at earthlink.net (Richard W. Solomon) Date: Tue, 5 Aug 2008 09:29:13 -0700 (GMT-07:00) Subject: [time-nuts] HP 5354A Plug-In Wanted Message-ID: <32332144.1217953754170.JavaMail.root@elwamui-cypress.atl.sa.earthlink.net> I acquired the counter (5345A) from a list member and would loke to get a Plug-In for it. I got sniped on one "over there". Anyone have a working 5354A they will part with ?? Thanks, Dick, W1KSZ From mensa999 at aol.com Tue Aug 5 12:56:37 2008 From: mensa999 at aol.com (MENSA999) Date: Tue, 5 Aug 2008 12:56:37 -0400 Subject: [time-nuts] (no subject) Message-ID: <2bc78ee1.5275.446e.bd29.e6b741ade1de@aol.com> This is a long shot but I am hoping that someone might be able to give me some Hints as to a problem that I am having with a Used 151-601 XL-DC Receiver that I recently purchased. When I first fired it up it showed a date of 1990 so I updated the Date to the current one using an "F" function and then went through a 24 hour Auto Mode set up. Once the receiver went into Time mode at the end of set up. I pushed the Location button and noted A good Lat, Lon and elevation had been established. The LCD was showing 3D for the most part and 5 or 6 SAT PRN's. Looking at Osc Stats I see Offsets ranging from the 10 -10 to 10 -12, Drift 10-08 to 10-09, Phase 10-08 to 10-10 and DAC ranging very slowly from 15950 up to 16400 or so. Now the bad news after days of operation when I run an F73 "Show Faults I am still showing GPS Unlocked, Position, Time Unknown (Even though a Lat, Lon had been established and UTC had been added through a Function command), and lastly a Time Error and Acquisition Error. I seem to be acquiring the satellites but not decoding their full message. I am not sure if this is due to a mistake I am making or a receiver failure. Any suggestions that anyone can give would be ever so greatly appreciated for I am at a loss and so far my web searches have been fruitless. Thank you all for your consideration in this..... Herb Belin Mensa999 at aol.com or 413 530 0048 Sorry for the repeats on this but I guess I have to ad carrige returns manually... From david.partridge at dsl.pipex.com Tue Aug 5 13:02:17 2008 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Tue, 5 Aug 2008 18:02:17 +0100 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: References: Message-ID: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> I'm using the Meanwell T30-B, but Tom van Baak's test on this shows a bit of phase noise at 1Hz offset which is a tad nasty: http://www.leapsecond.com/pages/tbolt/noise.htm I'm wondering if this can be reduced with a bit of extra de-coupling on the 5V supply, but haven't got round to scoping the 5V supply to see what happens every second (presumably as the output is sent to the serial port). Cheers Dave -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of F Mitchell Sent: 05 August 2008 17:24 To: time-nuts at febo.com Subject: [time-nuts] Power supply for Thunderbolt Anyone have a suggestion for a power supply for the Thunderbolt? Thanks Mitch W4OA _______________________________________________ time-nuts mailing list -- 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 Tue Aug 5 10:53:24 2008 From: gwinn at raytheon.com (Joseph M Gwinn) Date: Tue, 5 Aug 2008 10:53:24 -0400 Subject: [time-nuts] LPRO 101 ADJUSTMENT In-Reply-To: Message-ID: time-nuts-bounces at febo.com wrote on 08/02/2008 04:38:14 PM: > [snip] > > It would be nice to find a relatively simple and inexpensive 10MHz > synthesizer that has a resolution of closer to 1E-14 to avoid messing > with the EFC at all. A 48-bit-accumulator DDS chip such as the Analog Devices AD9852 will achieve such frequency resolution: 2^-48= 3.6*10^-15, call it 10^-14. The issue with a DDS is handling the various spurs. Arbitrary function generators such as the Agilent 34220A-001 (the -001 option means that an external 10 MHz reference signal is accepted) will also do the job, in a nice albeit expensive ($2.4K new) package. Joe Gwinn From bg at lysator.liu.se Tue Aug 5 13:33:24 2008 From: bg at lysator.liu.se (=?ISO-8859-1?Q?Bj=F6rn?= Gabrielsson) Date: Tue, 05 Aug 2008 19:33:24 +0200 Subject: [time-nuts] TrueTime XL-DC Problems In-Reply-To: References: Message-ID: <1217957604.7397.83.camel@bg-desktop> Hi Herb, I am not familiar with the details of the XL-DC. So if you get more informed suggestions, try them first... However your GPS receiver may be bitten by the GPS week rollower problem. http://www.colorado.edu/geography/gcraft/notes/gps/gpseow.htm http://tycho.usno.navy.mil/gps_week.html It is now GPS WK 1491 (467+1024). The GPS receiver firmware could have been "week-rollover-safe" by adding 1023 to "small" week numbers. Try to identify the GPS receiver model and search information on that particular unit. Can you eavesdrop on the GPS module? (Easier if it uses an ASCII NMEA message, more work if its a binary protocol). Check that it does output a valid date. Your model seems to be current with the manufacturer. Have you checked for the latest firmware? The DAC seem to move in the middle of the range. But have you double checked that the 10MHz output is as good as the unit says? Good Luck! -- Bj?rn On Tue, 2008-08-05 at 11:30 -0400, MENSA999 wrote: > This is a long shot but I am hoping that someone might be able to give > me some Hints as to a problem that I am having with a Used 151-601 > XL-DC Receiver that I recently purchased. When I first fired it up it > showed a date of 1990 so I updated the Date to the current one and > then went through a 24 hour Auto Mode set up. Once the receiver went > into Time mode at the end of set up. I pushed the Location button and > noted A good Lat, Lon and elevation had been established. The LCD was > showing 3D for the most part and 5 or 6 SAT PRN's. Looking at Osc > Stats I see Offsets ranging from the 10 -10 to 10 -12, Drift 10-08 to > 10-09, Phase 10-08 to 10-10 and DAC ranging very slowly from 15950 up > to 16400 or so. Now the bad news after days of operation I am still > showing GPS Unlocked, Position, Time Unknown (Even though a Lat, Lon > had been established and UTC had been added through a Function > command), Time Error and Acquisition Error ; when I do a F73 "Show > Faults" . I seem to be acquiring the satellites but not decoding their > full message. I am not sure if this is due to a mistake I am making or > a receiver failure. > Any suggestions that anyone can give would be ever so greatly > appreciated for I am at a loss and so far my web searches have been > fruitless. Thank you all for your consideration in this..... > > Herb Belin > > Mensa999 at aol.com or 413 530 0048 > _______________________________________________ > time-nuts mailing list -- 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 support at prologix.biz Tue Aug 5 13:38:35 2008 From: support at prologix.biz (Prologix) Date: Tue, 5 Aug 2008 10:38:35 -0700 Subject: [time-nuts] New Prologix GPIB-LAN Controller Message-ID: Hello, Prologix is happy to announce its newest product - GPIB-LAN Controller. Access your GPIB enabled instruments over a network (even over wireless) using the affordable, easy to use, Prologix GPIB-LAN controller! Use this controller to control, and to download screen plots and data from, Oscilloscopes, Logic Analyzers, Spectrum Analyzers and other GPIB enabled instruments. GPIB-LAN controller uses the same command interface as the popular Prologix GPIB-USB controller; the only difference is you connect to a TCP port instead of over USB. Being a network device there are no drivers to install. * No drivers required * Support for multiple devices * No GPIB cable needed; controller plugs on to instrument * All software configuration. No switches * Standard RJ-45 and IEEE 488 (Male) connectors Thanks to John Miles for adapting KE5FX GPIB toolkit to support Prologix GPIB-LAN controller. Now you can use the popular 7470, SSM and PN utilities over the net. Thanks to Ulrich Bangert for adapting EZGPIB to support Prologix GPIB-LAN controller http://store.prologix.biz/gpiblan-controller.html Regards, Abdul support at prologix.biz From boyscout at gmail.com Tue Aug 5 13:47:17 2008 From: boyscout at gmail.com (Matt Ettus) Date: Tue, 5 Aug 2008 10:47:17 -0700 Subject: [time-nuts] New Prologix GPIB-LAN Controller In-Reply-To: References: Message-ID: On Tue, Aug 5, 2008 at 10:38 AM, Prologix wrote: > Hello, > > > > Prologix is happy to announce its newest product - GPIB-LAN Controller. Will there be VXI-11 support? The ICS 8065 and Agilent E5810A both support it, along with most of the new test equipment that talks ethernet. It would be nice not to have to rewrite apps. Matt From GDowd at symmetricom.com Tue Aug 5 14:31:00 2008 From: GDowd at symmetricom.com (Greg Dowd) Date: Tue, 5 Aug 2008 11:31:00 -0700 Subject: [time-nuts] TrueTime XL-DC Problems In-Reply-To: References: Message-ID: Have you tried Symmetricom tech support? Truetime is now part of Symm's Timing, Test and Measurement division. Greg Dowd gdowd at symmetricom dot com (antispam format) Symmetricom, Inc. www.symmetricom.com "Everything should be made as simple as possible, but no simpler" Albert Einstein -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of MENSA999 Sent: Tuesday, August 05, 2008 8:31 AM To: time-nuts at febo.com Subject: [time-nuts] TrueTime XL-DC Problems This is a long shot but I am hoping that someone might be able to give me some Hints as to a problem that I am having with a Used 151-601 XL-DC Receiver that I recently purchased. When I first fired it up it showed a date of 1990 so I updated the Date to the current one and then went through a 24 hour Auto Mode set up. Once the receiver went into Time mode at the end of set up. I pushed the Location button and noted A good Lat, Lon and elevation had been established. The LCD was showing 3D for the most part and 5 or 6 SAT PRN's. Looking at Osc Stats I see Offsets ranging from the 10 -10 to 10 -12, Drift 10-08 to 10-09, Phase 10-08 to 10-10 and DAC ranging very slowly from 15950 up to 16400 or so. Now the bad news after days of operation I am still showing GPS Unlocked, Position, Time Unknown (Even though a Lat, Lon had been established and UTC had been added through a Function command), Time Error and Acquisition Error ; when I do a F73 "Show Faults" . I seem to be acquirin g the satellites but not decoding their full message. I am not sure if this is due to a mistake I am making or a receiver failure. Any suggestions that anyone can give would be ever so greatly appreciated for I am at a loss and so far my web searches have been fruitless. Thank you all for your consideration in this..... Herb Belin Mensa999 at aol.com or 413 530 0048 _______________________________________________ time-nuts mailing list -- 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 N3IZN at aol.com Tue Aug 5 16:07:55 2008 From: N3IZN at aol.com (N3IZN at aol.com) Date: Tue, 5 Aug 2008 16:07:55 EDT Subject: [time-nuts] Trimble GPSDO unit for sale - SOLD Message-ID: Sorry for not getting back to every one who inquired about the GPS unit I had for sale. I answered the emails in the order I got them and after a couple of no goes, I finally found a new home for it. There were a lot of emails and thought a group reply would be easier. Sorry for the bandwidth. Chris **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 ) From tom.k3io at gmail.com Tue Aug 5 17:10:15 2008 From: tom.k3io at gmail.com (Tom Clark, K3IO) Date: Tue, 05 Aug 2008 17:10:15 -0400 Subject: [time-nuts] The name "Totally Accurate Clock" Message-ID: <4898C1B7.4050004@verizon.net> Rob noted: Good point. How was the position of the so called "Totally Accurate Clock" obtained. Strange name though - no such thing as a totally accurate clock... :-) Rob Here is the story -- and some of the details are in my contributions on [1]http://gpstime.com: For many, many moons, I headed up NASA's program that developed Very Long Baseline Interferometry (VLBI) as a tool to make various geophysical measurements. The measurements yielded up * Accurate vector determination of the motions of the earth's tectonic plates ("continental drift", now known to ~20 microns/yr). * Very accurate measures of the rotation of the earth with respect to the celestial reference frame, aka UT1 (in effect "sundial time"), now observed at levels of a few tens of usec on a daily basis. VLBI is the "official" BIPM and USNO source of UT1, including the info on which we have a leap-second pending. * Accurate positions of the earth's rotation pole (polar motion, nutation & precession) and of a few hundred extragalactic radio sources at the sub-milliarcsecond level. * And some nifty astronomy too! Each VLBI station around the world has a Hydrogen Maser as its local clock (Jim Palfreyman's note concerned the VLBI station near Hobart, Tasmania) serving as both the stable short-term phase reference for microwave observations, as the timing clocks for data bits written onto tape (now replaced with disk arrays), and as the still longer term reference to tie between UT1 and UTC. If you look at my VLBI timing tutorials on [2]http://gpstime.com you will see info on VLBI's timing requirements. In the good old days (thru the mid-80s) we used some combination of Loran and traveling clocks to keep the network tied together. In the mid-80s we started using GPS for the task. The original GPS receivers were large, clunky devices. In the mid-90s I decided to come up with low-cost GPS timing receiver for the VLBI stations and I needed a short catchy name. At that time, Heathkit was selling a WWV receiver which could produce timing at levels of a few msec (on a good day) & Heath called it "The Most Accurate Clock". Also around that time, Hammacher-Schlemer was selling a WWVB wall clock that they also called "The Most Accurate Clock". My simple timing receiver was already producing sub-usec results using Motorola's PVT-6 "Six-Pack" 6-channel receiver, even in the face of Selective Availability (SA). Since I was achieving several orders-of-magnitude better results than the commercial "Most" receivers and since we could trace its ACCURACY all the way back to the USNO master clock, I needed a word much stronger than "Most" and thus was born the "Totally Accurate Clock" name; I modestly note the coincidence that TAC happen to be my initials! I began a campaign of replacing the timing systems at various stations with the first batch of 25 TACs using the PVT-6 receivers; I think that the unit Jim used for his GPSDO was an original 6-channel unit. You can judge the performance back then by the 6-week span of Maser/TAC data from Onsala Sweden plotted in my tutorials. Joe Taylor (Nobel Prize for his Pulsar work) verified that the original TAC was able to transfer time to Arecibo at levels of accuracy comparable to NIST's common view time transfer system (the service and equipment rental cost ~$5k/yr). Motorola then came out with their ONCORE series with 6 and then 8 channel receivers and I updated the design to the TAC-2. Because there was a lot of interest outside the VLBI community, I worked with TAPR to make a kit-form TAC-2 available to anyone. My friend Rick Hambly ([3]http://www.cnssys.com) saw a need for this receiver in a turn-key form, so he put the TAC-2 into his CNS Clock. He also transformed my crude "SHOWTIME" TAC support software into a full Windoze-based application which he called TAC32. He rolled into TAC32 the ability to automatically correct the timing results for the annoying 100 nsec sawtooth dither by providing a way to read a low-cost HP 53131 (or 132) counter, correcting its reading, and generating corrected logs. All told, between TAPR and CNS, something like 1000 of my TAC-2s found their way into the world. Rick has also adapted the newer Motorola (now iLotus) M12+ 12 channel receivers and has now rolled out is CNS Clock 2 which includes hardware sawtooth removal, IRIG time codes, a GPSDO and a bunch of other widgets. See his web site for more details. In the meantime, I retired from NASA in 2001 but I still stay involved with the VLBI and timing communities as the resident curmudgeon and referee of mis-spoken factoids. So that's where the name came from and how it evolved. Tom Clark References 1. http://gpstime.com/ 2. http://gpstime.com/ 3. http://www.cnssys.com/ From magnus at rubidium.dyndns.org Tue Aug 5 17:51:51 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 05 Aug 2008 23:51:51 +0200 Subject: [time-nuts] The name "Totally Accurate Clock" In-Reply-To: <4898C1B7.4050004@verizon.net> References: <4898C1B7.4050004@verizon.net> Message-ID: <4898CB77.9020608@rubidium.dyndns.org> Tom, Thanks for a fashinating little story! Cheers, Magnus From bruce.griffiths at xtra.co.nz Tue Aug 5 18:43:03 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 06 Aug 2008 10:43:03 +1200 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> Message-ID: <4898D777.1030909@xtra.co.nz> David C. Partridge wrote: > I'm using the Meanwell T30-B, but Tom van Baak's test on this shows a bit of > phase noise at 1Hz offset which is a tad nasty: > > http://www.leapsecond.com/pages/tbolt/noise.htm > > I'm wondering if this can be reduced with a bit of extra de-coupling on the > 5V supply, but haven't got round to scoping the 5V supply to see what > happens every second (presumably as the output is sent to the serial port). > > Cheers > Dave > > Dave If phase noise at 1Hz offset is a problem you will probably need a power supply filter with cutoff frequency well below 1Hz to make any discernable difference. Since the an RC filter will produce a voltage drop in the 5V supply the resistor value will have to be kept small and the capacitor value correspondingly large (several farads). It may be possible to stack 3 low ESR super capacitors in series (maximum voltage rating is around 2v -2.5V those with higher ratings are actually series connected stacks) to do this but this is a relatively expensive proposition. Alternatively a modified version of the Wenzel active power supply filter could be used if a series stack of 2 low ESR supercaps were substituted for the capacitor connected from the supply to the transistor base. The modified circuit stabilises the transistor's effective emitter resistance and keeps the active filter dc current low. It may also be possible to use a variation of Wenzel's opamp augmented active filter scheme, however the filter low frequency cutoff will have to be well below 1Hz for it to be effective. Bruce From James.P.Lux at jpl.nasa.gov Tue Aug 5 19:12:35 2008 From: James.P.Lux at jpl.nasa.gov (Jim Lux) Date: Tue, 05 Aug 2008 16:12:35 -0700 Subject: [time-nuts] The name "Totally Accurate Clock" In-Reply-To: <4898C1B7.4050004@verizon.net> References: <4898C1B7.4050004@verizon.net> Message-ID: <6.2.5.6.2.20080805155819.02da7f60@jpl.nasa.gov> At 02:10 PM 8/5/2008, Tom Clark, K3IO wrote: > Rob noted: > >Good point. How was the position of the so called "Totally Accurate Clock" >obtained. Strange name though - no such thing as a totally accurate clock... > > :-) > >Rob > > Here is the story -- and some of the details are in my contributions on > [1]http://gpstime.com: > For many, many moons, I headed up NASA's program that developed Very > Long Baseline Interferometry (VLBI) as a tool to make various > geophysical measurements. The measurements yielded up > * Accurate vector determination of the motions of the earth's > tectonic plates ("continental drift", now known to ~20 microns/yr). > * Very accurate measures of the rotation of the earth with respect to > the celestial reference frame, aka UT1 (in effect "sundial time"), > now observed at levels of a few tens of usec on a daily basis. VLBI > is the "official" BIPM and USNO source of UT1, including the info > on which we have a leap-second pending. > * Accurate positions of the earth's rotation pole (polar motion, > nutation & precession) and of a few hundred extragalactic radio > sources at the sub-milliarcsecond level. > * And some nifty astronomy too! And, such things as one way DeltaDOR measurements for navigation of deep space probes, and straight interferometry for measuring the position of the Lunar Rover. (the paper after yours at the 1972 PTTI conference) Other nifty applications at: http://www.sciencemag.org/cgi/reprint/sci;178/4061/607.pdf by Counselman, et al. Also used to do stuff like measure the winds on Titan and Venus. (but that's the astronomy Tom referred to) > Each VLBI station around the world has a Hydrogen Maser as its local > clock (Jim Palfreyman's note concerned the VLBI station near Hobart, > Tasmania) serving as both the stable short-term phase reference for > microwave observations, as the timing clocks for data bits written onto > tape (now replaced with disk arrays), and as the still longer term > reference to tie between UT1 and UTC. If you look at my VLBI timing > tutorials on [2]http://gpstime.com you will see info on VLBI's timing > requirements. For DeltaDOR they use a quasar as the (almost)simultaneous reference. I would have thought there would be a easy to find JPL reference on this (since we actually do it here, on the recent Phoenix landing, for instance), but it would appear that ESA has the nice description. http://www.esa.int/esapub/bulletin/bulletin128/bul128i_madde.pdf Here's a very simple description http://www2.jpl.nasa.gov/basics/bsf13-1.html Jim From GandalfG8 at aol.com Tue Aug 5 19:21:04 2008 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Tue, 5 Aug 2008 19:21:04 EDT Subject: [time-nuts] The name "Totally Accurate Clock" Message-ID: In a message dated 06/08/2008 00:15:08 GMT Daylight Time, James.P.Lux at jpl.nasa.gov writes: Also used to do stuff like measure the winds on Titan and Venus ------------------------ I did that once, but it's a pig of a job and was glad to get back!! From James.P.Lux at jpl.nasa.gov Tue Aug 5 19:37:07 2008 From: James.P.Lux at jpl.nasa.gov (Jim Lux) Date: Tue, 05 Aug 2008 16:37:07 -0700 Subject: [time-nuts] The name "Totally Accurate Clock" In-Reply-To: References: Message-ID: <6.2.5.6.2.20080805163616.02dfa130@jpl.nasa.gov> At 04:21 PM 8/5/2008, you wrote: >In a message dated 06/08/2008 00:15:08 GMT Daylight Time, >James.P.Lux at jpl.nasa.gov writes: > > >Also used to do stuff like measure the winds on Titan and Venus >------------------------ > > >I did that once, but it's a pig of a job and was glad to get back!! Yeah.. either your wet finger freezes or the acid burns are painful. From quenbob5 at pacbell.net Tue Aug 5 19:58:20 2008 From: quenbob5 at pacbell.net (Bob Q) Date: Tue, 5 Aug 2008 16:58:20 -0700 Subject: [time-nuts] Power supply for Thunderbolt References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> <4898D777.1030909@xtra.co.nz> Message-ID: <000a01c8f757$2402ae30$1801a8c0@BOBCEL1R7> I had a similar problem with my home-brew design. I found a "blip" with 1 second period on the output of the error amplifier. I couldn't eliminate it with extra power supply filtering. The high gain of the error amplifier picked up a very small voltage that developed on "ground". I solved it by supplying the phase detector and error amplifier with a separate 5 V supply. I tied the ground pin of the new 5 V regulator very close to the phase detector ground pin. Bob Q. ----- Original Message ----- From: "Bruce Griffiths" To: "Discussion of precise time and frequency measurement" Sent: Tuesday, August 05, 2008 3:43 PM Subject: Re: [time-nuts] Power supply for Thunderbolt > David C. Partridge wrote: >> I'm using the Meanwell T30-B, but Tom van Baak's test on this shows a bit >> of >> phase noise at 1Hz offset which is a tad nasty: >> >> http://www.leapsecond.com/pages/tbolt/noise.htm >> >> I'm wondering if this can be reduced with a bit of extra de-coupling on >> the >> 5V supply, but haven't got round to scoping the 5V supply to see what >> happens every second (presumably as the output is sent to the serial >> port). >> >> Cheers >> Dave >> >> > Dave > > If phase noise at 1Hz offset is a problem you will probably need a > power supply filter with cutoff frequency well below 1Hz to make any > discernable difference. > Since the an RC filter will produce a voltage drop in the 5V supply the > resistor value will have to be kept small and the capacitor value > correspondingly large (several farads). > It may be possible to stack 3 low ESR super capacitors in series > (maximum voltage rating is around 2v -2.5V those with higher ratings are > actually series connected stacks) to do this but this is a relatively > expensive proposition. > > Alternatively a modified version of the Wenzel active power supply > filter could be used if a series stack of 2 low ESR supercaps were > substituted for the capacitor connected from the supply to the > transistor base. The modified circuit stabilises the transistor's > effective emitter resistance and keeps the active filter dc current low. > > It may also be possible to use a variation of Wenzel's opamp augmented > active filter scheme, however the filter low frequency cutoff will have > to be well below 1Hz for it to be effective. > > 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 bruce.griffiths at xtra.co.nz Tue Aug 5 20:46:44 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 06 Aug 2008 12:46:44 +1200 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: <000a01c8f757$2402ae30$1801a8c0@BOBCEL1R7> References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> <4898D777.1030909@xtra.co.nz> <000a01c8f757$2402ae30$1801a8c0@BOBCEL1R7> Message-ID: <4898F474.1010402@xtra.co.nz> Bob Q wrote: > I had a similar problem with my home-brew design. I found a "blip" with 1 > second period on the output of the error amplifier. I couldn't eliminate > it with extra power supply filtering. The high gain of the error amplifier > picked up a very small voltage that developed on "ground". I solved it by > supplying the phase detector and error amplifier with a separate 5 V supply. > I tied the ground pin of the new 5 V regulator very close to the phase > detector ground pin. > Bob Q. > > Bob That involves an internal modification to the Thunderbolt which isnt really necessary as the problem is known to vanish when the power supply is quiet enough. For performance with other power supplies see: http://www.leapsecond.com/pages/tbolt/noise.htm The only real question are: Is possible to filter the given power supply sufficiently well. Which power supply rails need to be filtered? Bruce From bruce.griffiths at xtra.co.nz Tue Aug 5 21:14:03 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 06 Aug 2008 13:14:03 +1200 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> Message-ID: <4898FADB.8070308@xtra.co.nz> David C. Partridge wrote: > I'm using the Meanwell T30-B, but Tom van Baak's test on this shows a bit of > phase noise at 1Hz offset which is a tad nasty: > > http://www.leapsecond.com/pages/tbolt/noise.htm > > I'm wondering if this can be reduced with a bit of extra de-coupling on the > 5V supply, but haven't got round to scoping the 5V supply to see what > happens every second (presumably as the output is sent to the serial port). > > Cheers > Dave > > Dave Interaction between the power supply switching noise components and internal frequencies in the thunderbolt could produce the 1Hz spur. It would be useful to know the noise spectrum of the power supply outputs both at high and low frequencies. Careful filtering of the HF components of the power supply noise may be effective in reducing such interactions. Alternatively the supply could have a low level 1Hz oscillation superimposed on its output. It may well be easier and more cost effective to just use a lower noise supply rather than adding the complexity and cost of low and high frequency filtering. Bruce From rogburn at warpspeed1.net Tue Aug 5 21:22:22 2008 From: rogburn at warpspeed1.net (Robert Ogburn) Date: Tue, 5 Aug 2008 20:22:22 -0500 Subject: [time-nuts] Trimble Placer GPS400 In-Reply-To: Message-ID: On Monday, 8/4/08 Rob Wrote: -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of Rob Kimberley Sent: Monday, August 04, 2008 3:03 AM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Trimble Placer GPS400 Bob, SVEESIX is a Trimble GPS engine. From the report, it is telling you that the model you have uses that engine with those version numbers. What are you looking to restore? Not sure I understand your problem. Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Ogburn Sent: 03 August 2008 14:48 To: time-nuts at febo.com Subject: [time-nuts] Trimble Placer GPS400 We have a Trimble Placer GPS400 that reports version as: SVEESIX ver 4.06 (05/18/94) core ver 1.17 (12/21/93). Is this correct? If not, how do we restore? Thanks bob ========================================== From optomatic at rogers.com Tue Aug 5 21:46:54 2008 From: optomatic at rogers.com (Patrick) Date: Tue, 05 Aug 2008 21:46:54 -0400 Subject: [time-nuts] New Prologix GPIB-LAN Controller In-Reply-To: References: Message-ID: <4899028E.3080802@rogers.com> Hey Abdul Your new controller is on my shopping list, I just need to wait for some checks to arrive. Good work! -Patrick Prologix wrote: > Hello, > > > > Prologix is happy to announce its newest product - GPIB-LAN Controller. > > > > Access your GPIB enabled instruments over a network (even over wireless) > using the affordable, easy to use, Prologix GPIB-LAN controller! > > > > Use this controller to control, and to download screen plots and data from, > Oscilloscopes, Logic Analyzers, Spectrum Analyzers and other GPIB enabled > instruments. > > > > GPIB-LAN controller uses the same command interface as the popular Prologix > GPIB-USB controller; the only difference is you connect to a TCP port > instead of over USB. Being a network device there are no drivers to install. > > > > * No drivers required > > * Support for multiple devices > > * No GPIB cable needed; controller plugs on to instrument > > * All software configuration. No switches > > * Standard RJ-45 and IEEE 488 (Male) connectors > > > > Thanks to John Miles for adapting KE5FX GPIB toolkit to support Prologix > GPIB-LAN controller. Now you can use the popular 7470, SSM and PN utilities > over the net. > > > > Thanks to Ulrich Bangert for adapting EZGPIB to support Prologix GPIB-LAN > controller > > > > http://store.prologix.biz/gpiblan-controller.html > > > > Regards, > > Abdul > > support at prologix.biz > > > > _______________________________________________ > time-nuts mailing list -- 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 Tue Aug 5 21:55:56 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Tue, 5 Aug 2008 18:55:56 -0700 Subject: [time-nuts] TrueTime XL-DC Problems References: Message-ID: <001901c8f767$96e94020$0200a8c0@pc52> > When I first fired it up it showed a date of 1990 so I updated > the Date to the current one and then went through a 24 hour ... I would rather be able give you a solid answer; perhaps someone in the group will step forward with their own XL-DC story. It is possible when an unmodified surplus GPSDO powers up with a default date as old as 1990 and sort-of, partially works, that the cause of the problem is that the firmware is missing the upgrade for either WNRO (21-Aug-1999) or Y2K (31-Dec-1999). Anyone on the list have a working XL-DC? /tvb From n5en at wt.net Tue Aug 5 22:38:07 2008 From: n5en at wt.net (Steve Niles) Date: Tue, 05 Aug 2008 21:38:07 -0500 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: References: Message-ID: <48990E8F.9030303@wt.net> I use this one: http://www.mouser.com/Search/ProductDetail.aspx?qs=RCLU9o6%252bptzs793RA%252bLWWg%3d%3d Mouser p/n 826-LPT43 Seems to work OK. Steve N5EN > Message: 1 > Date: Tue, 5 Aug 2008 11:23:46 -0500 > From: "F Mitchell" > Subject: [time-nuts] Power supply for Thunderbolt > To: > > Anyone have a suggestion for a power supply for the > > Thunderbolt? > > > > Thanks > > Mitch W4OA From w1ksz at earthlink.net Wed Aug 6 00:20:57 2008 From: w1ksz at earthlink.net (Richard W. Solomon) Date: Tue, 5 Aug 2008 21:20:57 -0700 (GMT-07:00) Subject: [time-nuts] TrueTime XL-DC Problems Message-ID: <31837396.1217996458253.JavaMail.root@mswamui-andean.atl.sa.earthlink.net> Not sure what the differences are, but I have two of the XL-AK GPS Receivers, both work. 73, Dick, W1KSZ -----Original Message----- >From: Tom Van Baak >Sent: Aug 5, 2008 6:55 PM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] TrueTime XL-DC Problems > >> When I first fired it up it showed a date of 1990 so I updated >> the Date to the current one and then went through a 24 hour >... > >I would rather be able give you a solid answer; perhaps someone >in the group will step forward with their own XL-DC story. > >It is possible when an unmodified surplus GPSDO powers up with >a default date as old as 1990 and sort-of, partially works, that the >cause of the problem is that the firmware is missing the upgrade >for either WNRO (21-Aug-1999) or Y2K (31-Dec-1999). > >Anyone on the list have a working XL-DC? > >/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 df6jb at ulrich-bangert.de Wed Aug 6 00:46:35 2008 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 6 Aug 2008 06:46:35 +0200 Subject: [time-nuts] LPRO 101 ADJUSTMENT In-Reply-To: Message-ID: Jim, > A 48-bit-accumulator DDS chip such as the Analog Devices AD9852 will > achieve such frequency resolution: 2^-48= 3.6*10^-15, call > it 10^-14. The issue with a DDS is handling the various spurs. To be even more precise: It achieves this resolution in terms of the CLOCK frequency and not in terms of the OUTPUT frequency which may be consirable less resolution. Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Joseph M Gwinn > Gesendet: Dienstag, 5. August 2008 16:53 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] LPRO 101 ADJUSTMENT > > > time-nuts-bounces at febo.com wrote on 08/02/2008 04:38:14 PM: > > > > [snip] > > > > It would be nice to find a relatively simple and > inexpensive 10MHz > > synthesizer that has a resolution of closer to 1E-14 to > avoid messing > > with the EFC at all. > > A 48-bit-accumulator DDS chip such as the Analog Devices AD9852 will > achieve such frequency resolution: 2^-48= 3.6*10^-15, call > it 10^-14. The > issue with a DDS is handling the various spurs. > > Arbitrary function generators such as the Agilent 34220A-001 > (the -001 > option means that an external 10 MHz reference signal is > accepted) will > also do the job, in a nice albeit expensive ($2.4K new) package. > > Joe Gwinn > > _______________________________________________ > time-nuts mailing list -- 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 VK3FGJM at commtelns.com Wed Aug 6 01:01:27 2008 From: VK3FGJM at commtelns.com (VK3FGJM) Date: Wed, 6 Aug 2008 15:01:27 +1000 Subject: [time-nuts] Thunderbolt GPSDO coupled to a Rubidium Message-ID: Hi All, Has anybody integrated a Rubibium 10 MHz clock to their thunderbolt in place of the onboard oven? The reason for the question, I have a perfect working home made Rubidium source and distribution amp that I use in the stack. I have considered integrating it to the Thunderbolt, thus providing better long term accuracy. Maybe it's a waist of time! Regards Gerald Molenkamp VK3FGJM From james.p.lux at jpl.nasa.gov Wed Aug 6 01:16:10 2008 From: james.p.lux at jpl.nasa.gov (Jim Lux) Date: Tue, 05 Aug 2008 22:16:10 -0700 Subject: [time-nuts] LPRO 101 ADJUSTMENT In-Reply-To: References: Message-ID: <20080805221610.t33x9e3msw4ggwso@webmail.jpl.nasa.gov> Quoting Ulrich Bangert , on Tue 05 Aug 2008 09:46:35 PM PDT: > Jim, > >> A 48-bit-accumulator DDS chip such as the Analog Devices AD9852 will >> achieve such frequency resolution: 2^-48= 3.6*10^-15, call >> it 10^-14. The issue with a DDS is handling the various spurs. > > To be even more precise: It achieves this resolution in terms of the > CLOCK frequency and not in terms of the OUTPUT frequency which may be > consirable less resolution. > > Best regards > Ulrich Bangert And the 9852 is the older generation of DDSes from AD. The newer 99xx series is generally better (spur reduction built in, faster clocks, longer registers, more bits in the built in DAC) AND, there's all sorts of schemes combining a DDS and a PLL (granted, this rolls in a whole other set of problems) > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Joseph M Gwinn >> Gesendet: Dienstag, 5. August 2008 16:53 >> An: Discussion of precise time and frequency measurement >> Betreff: Re: [time-nuts] LPRO 101 ADJUSTMENT >> >> >> time-nuts-bounces at febo.com wrote on 08/02/2008 04:38:14 PM: >> >> > >> [snip] >> > >> > It would be nice to find a relatively simple and >> inexpensive 10MHz >> > synthesizer that has a resolution of closer to 1E-14 to >> avoid messing >> > with the EFC at all. >> >> A 48-bit-accumulator DDS chip such as the Analog Devices AD9852 will >> achieve such frequency resolution: 2^-48= 3.6*10^-15, call >> it 10^-14. The >> issue with a DDS is handling the various spurs. >> >> Arbitrary function generators such as the Agilent 34220A-001 >> (the -001 >> option means that an external 10 MHz reference signal is >> accepted) will >> also do the job, in a nice albeit expensive ($2.4K new) package. >> >> Joe Gwinn >> >> _______________________________________________ >> time-nuts mailing list -- 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 support at prologix.biz Wed Aug 6 09:11:44 2008 From: support at prologix.biz (Prologix) Date: Wed, 6 Aug 2008 06:11:44 -0700 Subject: [time-nuts] New Prologix GPIB-LAN Controller In-Reply-To: Message-ID: Prologix GPIB-LAN provides the same command interface as the popular Prologix GPIB-USB controller, making it easy to adapt existing programs. VXI-11 support may be emulated by developing a host side library. None is planned for now. But that could change depending on customer interest. Regards, Abdul www.prologix.biz -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Matt Ettus Sent: Tuesday, August 05, 2008 10:47 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] New Prologix GPIB-LAN Controller On Tue, Aug 5, 2008 at 10:38 AM, Prologix wrote: > Hello, > > > > Prologix is happy to announce its newest product - GPIB-LAN Controller. Will there be VXI-11 support? The ICS 8065 and Agilent E5810A both support it, along with most of the new test equipment that talks ethernet. It would be nice not to have to rewrite apps. Matt _______________________________________________ time-nuts mailing list -- 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 Wed Aug 6 13:36:07 2008 From: ed_palmer at sasktel.net (Ed Palmer) Date: Wed, 06 Aug 2008 11:36:07 -0600 Subject: [time-nuts] NavSync CW12 and CW25 In-Reply-To: References: Message-ID: <4899E107.7060401@sasktel.net> Has anyone worked with the NavSync CW12 GPS board or the CW25 module that its based on? It's been mentioned a few times on this mailing list, but not really evaluated or discussed to death. :-) I'm looking for a new GPS board and this one looks quite interesting. It's main feature is a programmable 10 Hz to 10 MHz oscillator that's phase-locked to the 1 PPS output. They're both available at the same time (on different pins). The user manual isn't online, but I asked them via email and got a copy with no problem. The datasheets and product briefs are available at: Datasheets http://www.navsync.com/docs/CW12-TIM_DS_V1.pdf http://www.navsync.com/docs/CW25-TIM_DS_Rev_1.pdf Product Briefs http://www.navsync.com/docs/CW12_TIM.pdf http://www.navsync.com/docs/CW25_TIM.pdf I see that they're not suggesting that this little module is a full-blown GPSDO. This app note talks about it. http://www.navsync.com/docs/AN03_GPS_Timing.pdf The prices are CW12 - $89, CW25 - $64 I have no relationship to Navsync or any reseller. I'm just a potential customer. Thanks, Ed From pvince at theiet.org Thu Aug 7 05:59:09 2008 From: pvince at theiet.org (Peter Vince) Date: Thu, 7 Aug 2008 10:59:09 +0100 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: <4898D777.1030909@xtra.co.nz> References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> <4898D777.1030909@xtra.co.nz> Message-ID: Bruce wrote: >... >It may be possible to stack 3 low ESR super capacitors in series >(maximum voltage rating is around 2v -2.5V those with higher ratings are >actually series connected stacks) to do this but this is a relatively >expensive proposition. >... Presumably you would need parallel resistors to ensure an even voltage split? And if so, are we talking about kilohms or megohms? Peter From bob.paddock at gmail.com Thu Aug 7 06:28:51 2008 From: bob.paddock at gmail.com (Bob Paddock) Date: Thu, 7 Aug 2008 06:28:51 -0400 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> <4898D777.1030909@xtra.co.nz> Message-ID: On Thu, Aug 7, 2008 at 5:59 AM, Peter Vince wrote: >>It may be possible to stack 3 low ESR super capacitors in series >>(maximum voltage rating is around 2v -2.5V those with higher ratings are >>actually series connected stacks) to do this but this is a relatively >>expensive proposition. > Presumably you would need parallel resistors to ensure an even > voltage split? And if so, are we talking about kilohms or megohms? Current is probably to low for this application, but it is worth noting: LTC3225 - 150mA Supercapacitor Charger Features * Low Noise Constant Frequency Charging of Two Series Supercapacitors * Automatic Cell Balancing Prevents Capacitor Overvoltage During Charging http://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1003,C1042,C1098,P84365 The part has been tested up to 400 Farads. Anyone ever look at using the LT1533 - Ultralow Noise 1A Switching Regulator as the basis of a power supply design? http://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1003,C1042,C1032,P1126 -- http://www.wearablesmartsensors.com/ http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/ From bruce.griffiths at xtra.co.nz Thu Aug 7 07:25:26 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 07 Aug 2008 23:25:26 +1200 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> <4898D777.1030909@xtra.co.nz> Message-ID: <489ADBA6.3010607@xtra.co.nz> Peter Vince wrote: > Bruce wrote: > >> ... >> It may be possible to stack 3 low ESR super capacitors in series >> (maximum voltage rating is around 2v -2.5V those with higher ratings are >> actually series connected stacks) to do this but this is a relatively >> expensive proposition. >> ... >> > > Presumably you would need parallel resistors to ensure an even > voltage split? And if so, are we talking about kilohms or megohms? > > Peter > > Peter The leakage of super caps is relatively low (at least the carbon aerogell foam variety) so around 10k or so should be OK. Bruce From tractorb at ihug.co.nz Thu Aug 7 08:21:44 2008 From: tractorb at ihug.co.nz (Dave Brown) Date: Fri, 8 Aug 2008 00:21:44 +1200 Subject: [time-nuts] Power supply for Thunderbolt References: <1E16BEC392C04989AE56CFBA90971A61@APOLLO> <4898D777.1030909@xtra.co.nz> Message-ID: <098601c8f888$292461b0$7900a8c0@athlon1200> ----- Original Message ----- From: "Bruce Griffiths" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, August 06, 2008 10:43 AM Subject: Re: [time-nuts] Power supply for Thunderbolt > David C. Partridge wrote: >> I'm using the Meanwell T30-B, but Tom van Baak's test on this shows >> a bit of >> phase noise at 1Hz offset which is a tad nasty: >> >> http://www.leapsecond.com/pages/tbolt/noise.htm >> >> I'm wondering if this can be reduced with a bit of extra >> de-coupling on the >> 5V supply, but haven't got round to scoping the 5V supply to see >> what >> happens every second (presumably as the output is sent to the >> serial port). >> >> Cheers >> Dave >> >> > Dave > > If phase noise at 1Hz offset is a problem you will probably need a > power supply filter with cutoff frequency well below 1Hz to make any > discernable difference. > Since the an RC filter will produce a voltage drop in the 5V supply > the > resistor value will have to be kept small and the capacitor value > correspondingly large (several farads). > It may be possible to stack 3 low ESR super capacitors in series > (maximum voltage rating is around 2v -2.5V those with higher ratings > are > actually series connected stacks) to do this but this is a > relatively > expensive proposition. > > Alternatively a modified version of the Wenzel active power supply > filter could be used if a series stack of 2 low ESR supercaps were > substituted for the capacitor connected from the supply to the > transistor base. The modified circuit stabilises the transistor's > effective emitter resistance and keeps the active filter dc current > low. > > It may also be possible to use a variation of Wenzel's opamp > augmented > active filter scheme, however the filter low frequency cutoff will > have > to be well below 1Hz for it to be effective. > > Bruce It would be interesting to see how the 'red panel' Thunderbolts (the packaged type that run from an included switching supply fed from 24 VDC) perform under a test regime such as that TVB used to compare various three rail power supplies. In 'distant past' posts, maybe 18 months back, it was suggested that this supply is a particularly good performer, but IIRC no data was supplied to support this statement. Anyone able to oblige? DaveB, NZ From jmiles at pop.net Thu Aug 7 09:21:25 2008 From: jmiles at pop.net (John Miles) Date: Thu, 7 Aug 2008 06:21:25 -0700 Subject: [time-nuts] Power supply for Thunderbolt In-Reply-To: <098601c8f888$292461b0$7900a8c0@athlon1200> Message-ID: > > It would be interesting to see how the 'red panel' Thunderbolts (the > packaged type that run from an included switching supply fed from 24 > VDC) perform under a test regime such as that TVB used to compare > various three rail power supplies. In 'distant past' posts, maybe 18 > months back, it was suggested that this supply is a particularly good > performer, but IIRC no data was supplied to support this statement. > Anyone able to oblige? This (cluttered) graph is indicative of the results I've seen. The Lucent supply used in the older red-and-black labelled Thunderbolts was not very clean, and its proximity and orientation adjacent to the Thunderbolt's PCB didn't help. Red = the new ("TAPR") Thunderbolt with my old Thunderbolt's Lucent supply Blue = the old Thunderbolt with its Lucent supply Orange = the new Thunderbolt with the supply Tom chose Purple = the old Thunderbolt with Tom's supply The reference for the red trace was somewhat noisier below 100 Hz than the one used for the others. You should assume that the red trace coincides with the orange one below 100 Hz. -- john, KE5FX -------------- next part -------------- A non-text attachment was scrubbed... Name: tbolts.gif Type: image/gif Size: 61262 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080807/72e00701/attachment-0001.gif From w1ksz at earthlink.net Thu Aug 7 13:30:29 2008 From: w1ksz at earthlink.net (Richard W. Solomon) Date: Thu, 7 Aug 2008 10:30:29 -0700 (GMT-07:00) Subject: [time-nuts] Symmetricom Schematics Message-ID: <5271864.1218130229796.JavaMail.root@elwamui-darkeyed.atl.sa.earthlink.net> I have two of the TrueTime XL-AK GPS Receivers. Both came with manuals that did not include schematics. I thought I would ask Symmetricom (the now owners of TrueTime) if they would supply me with schematics. Foolish me ... They flat out refused to supply them with no explanation and no reply to any further e-Mail. We are not talking about Nuclear Weapon design here, only a GPS Receiver that is 15 (?) years old. Someone in their Corporate Office (so far unreachable) should re-think this position as it does not present them in very good light. (not to mention bad Marketing and poor press). -EOR- 73, Dick, W1KSZ From postmaster Thu Aug 7 13:36:26 2008 From: postmaster (postmaster) Date: 7 Aug 2008 18:36:26 +0100 Subject: [time-nuts] ***Your message was blocked*** Message-ID: WHAT HAPPENED ? =============== Your message "[time-nuts] Symmetricom Schematics" was not delivered. 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INTERNET HEADERS ================ X-SPF-Guess:pass (Exclaimer Mail Utilities: domain of febo.com designates 24.123.66.139 as permitted sender) client-ip=24.123.66.139; envelope-from=time-nuts-bounces+dgeoghegan=conwin.ie at febo.com; helo=febo.com; X-SPF-Result:3 X-ExAntiSpamFlags:SMTP_FROM_NOT_EQUAL_822_FROM DNSRHSBL_LISTED SPF_PASS SPF_GUESS X-ExSpamID:str=0001.0A0B0207.489B31DC.009B,ss=1,fgs=0 X-OriginalArrivalTime:07 Aug 2008 17:36:19.0984 (UTC) FILETIME=[1A581100:01C8F8B4] Return-Path:time-nuts-bounces+dgeoghegan=conwin.ie at febo.com Errors-To:time-nuts-bounces+dgeoghegan=conwin.ie at febo.com RETRY X-SA-Exim-Scanned:No (on febo.com); SAEximRunCond expanded to false X-SA-Exim-Mail-From:time-nuts-bounces at febo.com X-SA-Exim-Connect-IP:127.0.0.1 Sender:time-nuts-bounces at febo.com Content-Transfer-Encoding:7bit Content-Type:text/plain; charset="us-ascii" List-Subscribe:, List-Help: List-Post: List-Archive: List-Unsubscribe:, List-Id:Discussion of precise time and frequency measurement Reply-To:"Richard W. Solomon" , Discussion of precise time and frequency measurement Precedence:list X-Mailman-Version:2.1.9 X-BeenThere:time-nuts at febo.com Subject:[time-nuts] Symmetricom Schematics X-Spam-Level:X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00 autolearn=ham version=3.2.3 X-Spam-Checker-Version:SpamAssassin 3.2.3 (2007-08-08) on meow.febo.com X-Originating-IP:209.86.224.33 X-ELNK-Trace:a3c96698008b82d674bf435c0eb9d47857917ca117f2a1a39f4549106b00c0ae9efe4054c37f43aa350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Mailer:EarthLink Zoo Mail 1.0 Mime-Version:1.0 To:time-nuts at febo.com From:"Richard W. Solomon" Date:Thu, 7 Aug 2008 10:30:29 -0700 (GMT-07:00) PrevMsg-ID:<5271864.1218130229796.JavaMail.root at elwamui-darkeyed.atl.sa.earthlink.net> Received:from 75.164.64.103 by webmail.earthlink.net with HTTP; Thu, 7 Aug 2008 13:30:29 -0400 Received:from [209.86.224.33] (helo=elwamui-darkeyed.atl.sa.earthlink.net) by elasmtp-kukur.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1KR9Jl-0000vq-Qk for time-nuts at febo.com; Thu, 07 Aug 2008 13:30:29 -0400 Received:from elasmtp-kukur.atl.sa.earthlink.net ([209.86.89.65]) by febo.com with esmtp (Exim 4.68) (envelope-from ) id 1KR9K1-0007hm-GD for time-nuts at febo.com; Thu, 07 Aug 2008 13:30:54 -0400 Received:from localhost ([127.0.0.1] helo=febo.com ident=foobar) by febo.com with esmtp (Exim 4.68) (envelope-from ) id 1KR9KD-0007i6-QO; Thu, 07 Aug 2008 13:30:57 -0400 Received:from febo.com ([24.123.66.139]) by conwin.ie with Microsoft SMTPSVC(6.0.3790.3959); Thu, 7 Aug 2008 18:36:19 +0100 ============== END OF MESSAGE From time-nuts at kasperkp.dk Thu Aug 7 13:58:14 2008 From: time-nuts at kasperkp.dk (Kasper Pedersen) Date: Thu, 07 Aug 2008 19:58:14 +0200 Subject: [time-nuts] bounce - apologies In-Reply-To: <5271864.1218130229796.JavaMail.root@elwamui-darkeyed.atl.sa.earthlink.net> References: <5271864.1218130229796.JavaMail.root@elwamui-darkeyed.atl.sa.earthlink.net> Message-ID: <489B37B6.7080403@kasperkp.dk> I must apologize for screwing up the mail server configuration. I do not believe in generating replies to usually falsified addresses. And I'm also rather confused as to why it happened now, and not a lot earlier. To make it short, it is supposedly fixed. /Kasper Pedersen From t_list_1_only at braw.co.uk Thu Aug 7 16:50:02 2008 From: t_list_1_only at braw.co.uk (David ) Date: Thu, 7 Aug 2008 21:50:02 +0100 Subject: [time-nuts] NavSync CW12 and CW25 In-Reply-To: Message-ID: <000501c8f8cf$2b114550$0200a8c0@hp6110> Ed, I've been playing with a CW12, it basically appears to do what they say but I will not confirm any numbers for the moment, it certainly compares to my VLF derived 10MHz signals. I was looking to build a GPSDO and 10MHz from the GPS Rx seemed a better starting point than 1PPS. I'm only now near to completing part two of the exercise, phase locking a 10MHz double oven XO to the CW12 10MHz, the phase noise on the CW12 output is rather significant and needs cleaning for most applications. The ssb numbers I see from the CW12 (using an HP8560E) relative to the 10MHz carrier are : 1kHz -80 dBc/Hz 10kHz -102 dBc/Hz 100kHz -109 dBc/Hz 1MHz -126 dBc/Hz The signal is far from a pure line, close in there is a set of sidebands based on harmonics of 132 with the fundamental at -22dBc, there are various synthesis artefacts. This unit clearly needs filtering. The PLL I've built to clean it up is essentially a simple 2nd/3rd order loop with the phase comparison at 78kHz (sigs divided by 128), my model claims the 3dB closed bandwidth will be 0.3 Hz and sideband suppression about 127dB at 1kHz offset in principle. In reality I'll need to play with it to look at the real world limitations of acquisition, loop BW, analogue offsets etc . The OCXO I'm locking is a Temex part, a 'Doc1478-D" which seems to be from their S110 series. It claims to manage -145dBc at 1kHz offset. There were on ebay at low cost a while ago, everything else has largely been built from scrap which has biased the design ever so slightly, the less it costs the more amusing the project if you are not doing it for a customer. The slight disappointment has been the lack of support information about the CW12 on the web, when I spoke to them in March they said their site was going to be updated by the end of that month, clearly they have dropped the ball somewhere but the email support seems responsive. I think I've seen the CW25 appear in a recent GPSDO from Quartzlock, have a look at : http://www.quartzlock.com/cgi-bin/servepage.cgi?usr=61390&page=tech_DS_E8-X. pdf This appears to use a DDS/PLL to clean the reference clock rather than a large and expensive OCXO. Starting afresh I may have gone for the CW25 but I've got the CW12 so not thought much more about it. Regards David Mackenzie (GM4HJQ) From wje at quackers.net Thu Aug 7 21:20:47 2008 From: wje at quackers.net (wje) Date: Thu, 07 Aug 2008 21:20:47 -0400 Subject: [time-nuts] HP 5371A problem Message-ID: <489B9F6F.7020402@quackers.net> The cpu card in my 5371A seems to have died. It's asserting reset constantly, with lights 1 and 6 on. Unfortunately, my service manual doesn't include any schematics for that card. Does anyone have any suggestions? (other than doing a lot of tedious tracing) -- Bill Ezell ---------- They said 'Windows or better' so I used Linux. From vk2ihl at gmail.com Fri Aug 8 00:18:06 2008 From: vk2ihl at gmail.com (Pascal Nguyen) Date: Fri, 8 Aug 2008 14:18:06 +1000 Subject: [time-nuts] NavSync CW12 and CW25 In-Reply-To: <4899E107.7060401@sasktel.net> References: <4899E107.7060401@sasktel.net> Message-ID: <22ddffe10808072118i142373c5m2e26767deb2df3c@mail.gmail.com> Hi Ed I build a 432.424MHz and 144.424MHz beacons for radio amateur application based on CW25-TIM modules ($150 ea july-07). I cannot provide any further details than the spec published by Navsync, due to lack of measurement facility, my set up is simply a Rb standard and two RT662 HF receivers driven with 5MHz source from Rb 10MHz/2) . Audio outputs are directed to PC soundcard and water falls are visually compared, an entry level for amateur like myself. I etched the PC board for 3V3 SM power supply, backup battery, RS 232 converter (3v level) and 1PPS, NCO output, NMEA output, status LED indicators. My first board was populated with CW25 NAV, the only module available at that time, max freq 10MHz NCO. My second with CW25 TIM, max freq 30 MHz NCO Control the NCO is quite simple, via simple protocols, ie 10MHz output is such as " $PRTHS,FRQD,10.000.000 ". The CW25 TIM, factory default NCO output is 10 MHz, since startup and will lock to 1pps when status fixed, the module is running warm to touch at, I suppose an ovenised crystal is inside. I do not have the CW12, if the module is CW25TIM, it is worthy to get the CW12 to save the pain of etching a PCB. Pascal Nguyen On 8/7/08, Ed Palmer wrote: > Has anyone worked with the NavSync CW12 GPS board or the CW25 module > that its based on? It's been mentioned a few times on this mailing > list, but not really evaluated or discussed to death. :-) > > I'm looking for a new GPS board and this one looks quite interesting. > It's main feature is a programmable 10 Hz to 10 MHz oscillator that's > phase-locked to the 1 PPS output. They're both available at the same > time (on different pins). > > The user manual isn't online, but I asked them via email and got a copy > with no problem. The datasheets and product briefs are available at: > > Datasheets > http://www.navsync.com/docs/CW12-TIM_DS_V1.pdf > http://www.navsync.com/docs/CW25-TIM_DS_Rev_1.pdf > > Product Briefs > http://www.navsync.com/docs/CW12_TIM.pdf > http://www.navsync.com/docs/CW25_TIM.pdf > > I see that they're not suggesting that this little module is a > full-blown GPSDO. This app note talks about it. > > http://www.navsync.com/docs/AN03_GPS_Timing.pdf > > The prices are CW12 - $89, CW25 - $64 > > I have no relationship to Navsync or any reseller. I'm just a potential > customer. > > Thanks, > 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 magnus at rubidium.dyndns.org Fri Aug 8 00:31:48 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 8 Aug 2008 06:31:48 +0200 (CEST) Subject: [time-nuts] Symmetricom Schematics In-Reply-To: <5271864.1218130229796.JavaMail.root@elwamui-darkeyed.atl.sa.earthlink .net> References: <5271864.1218130229796.JavaMail.root@elwamui-darkeyed.atl.sa.earthlink.net> Message-ID: > I have two of the TrueTime XL-AK GPS Receivers. Both came with manuals > that did not include schematics. > I thought I would ask Symmetricom (the now owners of TrueTime) if they > would > supply me with schematics. Foolish me ... > > They flat out refused to supply them with no explanation and no reply to > any > further e-Mail. We are not talking about Nuclear Weapon design here, only > a > GPS Receiver that is 15 (?) years old. > > Someone in their Corporate Office (so far unreachable) should re-think > this > position as it does not present them in very good light. (not to mention > bad > Marketing and poor press). As a reference I have received assistance from HP/Agilent, Oscilloquartz and Pendulum when "walking in the front door" through official channels. For Symmetricom individual engineers have reached out. Last experience was Oscilloquartz that happilly scanned relevant pages on the old OSA 3210 manual to aid me in having the PSU repaired. Now that one needs trimming to lock in again. I was also given a replacement thermos for my 8600 within days, but that was maybe more of a friendly gesture, but shows the attitude. However, such friendly gestures make me feel comfortable with the company and shapes my total experience with them. HP/Agilents backlog effort on providing manuals and service manuals have been of great use and also a great source of reference. Supporting the night time hobby projects can aid in sales in the daytime activities. But if only looking at next sale, the soft issues like these gets lost. Cheers, Magnus From bruce.griffiths at xtra.co.nz Fri Aug 8 01:33:08 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 08 Aug 2008 17:33:08 +1200 Subject: [time-nuts] HP 5371A problem In-Reply-To: <489B9F6F.7020402@quackers.net> References: <489B9F6F.7020402@quackers.net> Message-ID: <489BDA94.6020506@xtra.co.nz> wje wrote: > The cpu card in my 5371A seems to have died. It's asserting reset > constantly, with lights 1 and 6 on. > > Unfortunately, my service manual doesn't include any schematics for that > card. Does anyone have any suggestions? (other than doing a lot of > tedious tracing) > > Try fig 7G8 in part 2 of the 5371A manual available on the Agilent website. Bruce From bruce.griffiths at xtra.co.nz Fri Aug 8 01:34:37 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 08 Aug 2008 17:34:37 +1200 Subject: [time-nuts] HP 5371A problem In-Reply-To: <489B9F6F.7020402@quackers.net> References: <489B9F6F.7020402@quackers.net> Message-ID: <489BDAED.3020501@xtra.co.nz> wje wrote: > The cpu card in my 5371A seems to have died. It's asserting reset > constantly, with lights 1 and 6 on. > > Unfortunately, my service manual doesn't include any schematics for that > card. Does anyone have any suggestions? (other than doing a lot of > tedious tracing) > > Correction: Figure 7G8 on page 7G17 for the processor board schematic. Bruce From j.koegel5 at gmail.com Fri Aug 8 05:06:49 2008 From: j.koegel5 at gmail.com (=?ISO-8859-1?Q?J=FCrg_K=F6gel?=) Date: Fri, 8 Aug 2008 11:06:49 +0200 Subject: [time-nuts] HP 5371A problem In-Reply-To: <489B9F6F.7020402@quackers.net> References: <489B9F6F.7020402@quackers.net> Message-ID: <390229150808080206s6262ddddw884479312a165582@mail.gmail.com> My 5372A had the same problems. Error: Contact problems in IC sockets and jumpers Remove IC and jumpers and put those back. This solved my problems Juerg From wje at quackers.net Fri Aug 8 07:03:28 2008 From: wje at quackers.net (wje) Date: Fri, 08 Aug 2008 07:03:28 -0400 Subject: [time-nuts] HP 5371A problem In-Reply-To: <489BDAED.3020501@xtra.co.nz> References: <489B9F6F.7020402@quackers.net> <489BDAED.3020501@xtra.co.nz> Message-ID: <489C2800.6050900@quackers.net> Thanks. I don't know how I missed those manuals on the Agilent site; I had looked there a while ago. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Bruce Griffiths wrote: wje wrote: The cpu card in my 5371A seems to have died. It's asserting reset constantly, with lights 1 and 6 on. Unfortunately, my service manual doesn't include any schematics for that card. Does anyone have any suggestions? (other than doing a lot of tedious tracing) Correction: Figure 7G8 on page 7G17 for the processor board schematic. Bruce _______________________________________________ time-nuts mailing list -- [1]time-nuts at febo.com To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts at febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From didier at cox.net Fri Aug 8 07:53:10 2008 From: didier at cox.net (Didier Juges) Date: Fri, 8 Aug 2008 06:53:10 -0500 Subject: [time-nuts] HP 5371A problem In-Reply-To: <390229150808080206s6262ddddw884479312a165582@mail.gmail.com> References: <489B9F6F.7020402@quackers.net> <390229150808080206s6262ddddw884479312a165582@mail.gmail.com> Message-ID: <00fe01c8f94d$55369e60$04000100@didierhp> On both of my 5370As, the only way to permanently fix socket problems of that type was to replace all the sockets with gold plated, machined pin sockets. On the 5370, that was easy because the boards have relatively large holes compared to the socket pins, and there is no ground plane, so it was easy to unsolder the pins with the good desoldering tool I have access to at work. Prior to that, I had removed all chips and sprayed the sockets with DeOxIt Gold several times, but the problem always came back pretty quickly. I think it was tin wiskers. Didier > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of J?rg K?gel > Sent: Friday, August 08, 2008 4:07 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] HP 5371A problem > > My 5372A had the same problems. > Error: Contact problems in IC sockets and jumpers Remove IC > and jumpers and put those back. > This solved my problems > > Juerg > > _______________________________________________ > time-nuts mailing list -- 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 Fri Aug 8 12:08:40 2008 From: ed_palmer at sasktel.net (Ed Palmer) Date: Fri, 08 Aug 2008 10:08:40 -0600 Subject: [time-nuts] time-nuts Digest, Vol 49, Issue 12 In-Reply-To: References: Message-ID: <489C6F88.4020600@sasktel.net> > Date: Thu, 7 Aug 2008 21:50:02 +0100 > From: "David " > Subject: Re: [time-nuts] NavSync CW12 and CW25 > To: > Message-ID: <000501c8f8cf$2b114550$0200a8c0 at hp6110> > Content-Type: text/plain; charset="us-ascii" > > Ed, > > I've been playing with a CW12, it basically appears to do what they say but > I will not confirm any numbers for the moment, it certainly compares to my > VLF derived 10MHz signals. I was looking to build a GPSDO and 10MHz from the > GPS Rx seemed a better starting point than 1PPS. > My thoughts exactly. I've been playing with a Jupiter GPS board which has a 10 KHz output, but it died on me so I'm that's why I'm looking for a replacement. > I'm only now near to completing part two of the exercise, phase locking a > 10MHz double oven XO to the CW12 10MHz, the phase noise on the CW12 output > is rather significant and needs cleaning for most applications. The ssb > numbers I see from the CW12 (using an HP8560E) relative to the 10MHz carrier > are : > > 1kHz -80 dBc/Hz > 10kHz -102 dBc/Hz > 100kHz -109 dBc/Hz > 1MHz -126 dBc/Hz > > The signal is far from a pure line, close in there is a set of sidebands > based on harmonics of 132 with the fundamental at -22dBc, there are various > synthesis artefacts. This unit clearly needs filtering. > I thought it was good of Navsync to admit in the app note that their signal isn't particularly clean. I'm a rank amateur in this area, but if you changed the output frequency of the CW25 is it possible that you might find a 'sweet spot' that would give you a cleaner signal - either by matching or avoiding various harmonics of the internal clock(s)? I noticed in the datasheet that they spec the processor as 'up to 120 MHz'. If they're saying that the clock speed varies while operating then forget my question. > The PLL I've built to clean it up is essentially a simple 2nd/3rd order loop > with the phase comparison at 78kHz (sigs divided by 128), my model claims > the 3dB closed bandwidth will be 0.3 Hz and sideband suppression about 127dB > at 1kHz offset in principle. In reality I'll need to play with it to look at > the real world limitations of acquisition, loop BW, analogue offsets etc . > Did you divide down the output from the CW12? I see that you can set this frequency, but I wondered if this setting was non-volatile or if the frequency would return to 10 MHz after a loss of power. I'm assuming that the on-board battery would keep it as long as possible. > The OCXO I'm locking is a Temex part, a 'Doc1478-D" which seems to be from > their S110 series. It claims to manage -145dBc at 1kHz offset. There were on > ebay at low cost a while ago, everything else has largely been built from > scrap which has biased the design ever so slightly, the less it costs the > more amusing the project if you are not doing it for a customer. > Yeah, it's no fun to just go buy a bunch of parts. Some of my stuff looks like it came out of Dr. Frankenstein's lab. Of course, sometimes you have to dig out your wallet. I picked up a couple of those 'naked' HP Z3801a oscillators (basically HP 10811 oscillators with an second oven) that showed up on Ebay a month or so ago. I'm planning on using that for my OCXO. The 'Frankenstein' aspect will be fulfilled because I'll have to fabricate an outer casing for the oscillator and build a controller for the outer oven. > The slight disappointment has been the lack of support information about the > CW12 on the web, when I spoke to them in March they said their site was > going to be updated by the end of that month, clearly they have dropped the > ball somewhere but the email support seems responsive. I asked for the user manual in June and they responded quickly, but didn't mention anything about a website update. > I think I've seen the > CW25 appear in a recent GPSDO from Quartzlock, have a look at : > > http://www.quartzlock.com/cgi-bin/servepage.cgi?usr=61390&page=tech_DS_E8-X. > pdf > Yeah, that little module looks familiar doesn't it? The picture's not very clear, but you can just make out the Hirose connector in the corner of the module near the TNC connector. > This appears to use a DDS/PLL to clean the reference clock rather than a > large and expensive OCXO. > > Starting afresh I may have gone for the CW25 but I've got the CW12 so not > thought much more about it. > > Regards > David Mackenzie (GM4HJQ) > Thanks very much for the info, David. Ed From ed_palmer at sasktel.net Fri Aug 8 12:45:56 2008 From: ed_palmer at sasktel.net (Ed Palmer) Date: Fri, 08 Aug 2008 10:45:56 -0600 Subject: [time-nuts] NavSync CW12 and CW25 In-Reply-To: References: Message-ID: <489C7844.8010006@sasktel.net> > Date: Fri, 8 Aug 2008 14:18:06 +1000 > From: "Pascal Nguyen" > Subject: Re: [time-nuts] NavSync CW12 and CW25 > To: "Discussion of precise time and frequency measurement" > Message-ID: <22ddffe10808072118i142373c5m2e26767deb2df3c at mail.gmail.com> > Content-Type: text/plain; charset=UTF-8 > Hi Ed > I build a 432.424MHz and 144.424MHz beacons for radio amateur application > based on CW25-TIM modules ($150 ea july-07). > I cannot provide any further details than the spec published by Navsync, due > to lack of measurement facility, my set up is simply a Rb standard and two > RT662 HF receivers driven with 5MHz source from Rb 10MHz/2) . Audio outputs > are directed to PC soundcard and water falls are visually compared, an entry > level for amateur like myself. > I etched the PC board for 3V3 SM power supply, backup battery, RS 232 > converter (3v level) and 1PPS, NCO output, NMEA output, status LED > indicators. > My first board was populated with CW25 NAV, the only module available at > that time, max freq 10MHz NCO. > My second with CW25 TIM, max freq 30 MHz NCO It looks like they've dropped the CW25-NAV. It doesn't seem to be mentioned on their site. They've also reduced the output frequency on the CW25-TIM to 10 MHz. In fact, yours must be a very early model because even digging through old web pages, I can't find any mention of a 30 MHz output. Don't lose that one, you'll never find another like it! > Control the NCO is quite simple, via simple protocols, ie 10MHz output is > such as " $PRTHS,FRQD,10.000.000 ". > The CW25 TIM, factory default NCO output is 10 MHz, since startup and will > lock to 1pps when status fixed, the module is running warm to touch at, I > suppose an ovenised crystal is inside. > I do not have the CW12, if the module is CW25TIM, it is worthy to get the > CW12 to save the pain of etching a PCB. > Pascal Nguyen Thanks for the info, Ed From wje at quackers.net Fri Aug 8 13:40:37 2008 From: wje at quackers.net (wje) Date: Fri, 08 Aug 2008 13:40:37 -0400 Subject: [time-nuts] HP 5371A problem In-Reply-To: <390229150808080206s6262ddddw884479312a165582@mail.gmail.com> References: <489B9F6F.7020402@quackers.net> <390229150808080206s6262ddddw884479312a165582@mail.gmail.com> Message-ID: <489C8515.1050807@quackers.net> Thanks, all. In this case, it was a 74ALS1035 OC hex buffer that gave up the ghost. I've temporarily replaced it with 6 diodes, which works like a charm. After all, what's an OC buffer but a diode plus a little 1x gain? Bill Ezell ---------- They said 'Windows or better' so I used Linux. J?rg K?gel wrote: > My 5372A had the same problems. > Error: Contact problems in IC sockets and jumpers > Remove IC and jumpers and put those back. > This solved my problems > > Juerg > > _______________________________________________ > time-nuts mailing list -- 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 TheInfamousFlavio at hotmail.com Fri Aug 8 17:24:42 2008 From: TheInfamousFlavio at hotmail.com (TheInfamousFlavio at hotmail.com) Date: Fri, 8 Aug 2008 17:24:42 -0400 Subject: [time-nuts] Double-Oven Thunderbolt on Ebay Message-ID: Does anyone have a double-oven thunderbolt like the one that's now listed on ebay? If so, do you have any phase-noise or other performance data on it? -Flavio From jmiles at pop.net Fri Aug 8 18:23:27 2008 From: jmiles at pop.net (John Miles) Date: Fri, 8 Aug 2008 15:23:27 -0700 Subject: [time-nuts] Double-Oven Thunderbolt on Ebay In-Reply-To: Message-ID: I don't have any of the 10811-60158s, but I did buy two of the 10811-60168s that were up for auction recently. The -60168s seem to be really good performers (from memory, -106 dBc/Hz at 1 Hz, -139 at 10, -155 at 100, -164 at 1000, when I measured them against each other.) I have never seen any specs for them, or anything else about them. If someone wants to lend one of the -60158s to me, I'll benchmark it against one of the -60268s. Tom or JohnA, have either of you run any Allan plots on a 10811-60268? I'd be curious to see how they do. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of TheInfamousFlavio at hotmail.com > Sent: Friday, August 08, 2008 2:25 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Double-Oven Thunderbolt on Ebay > > > Does anyone have a double-oven thunderbolt like the one that's > now listed on ebay? If so, do you have any phase-noise or other > performance data on it? > > -Flavio > _______________________________________________ > time-nuts mailing list -- 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 Aug 8 18:29:45 2008 From: jmiles at pop.net (John Miles) Date: Fri, 8 Aug 2008 15:29:45 -0700 Subject: [time-nuts] Double-Oven Thunderbolt on Ebay In-Reply-To: Message-ID: > Tom or JohnA, have either of you run any Allan plots on a > 10811-60268? I'd > be curious to see how they do. Er, -60168, that is. -- john, KE5FX From jra at febo.com Fri Aug 8 18:30:52 2008 From: jra at febo.com (John Ackermann N8UR) Date: Fri, 08 Aug 2008 18:30:52 -0400 Subject: [time-nuts] Double-Oven Thunderbolt on Ebay In-Reply-To: References: Message-ID: <489CC91C.3060604@febo.com> I'm measuring my pair of eBay -60158s right now and will post some results probably after the weekend. I've never seen the -60268s. One thing to note -- good phase noise and good ADEV don't necessarily go together. Case in point is the -60158s are spec'd at 1x10e-12 at 1 second, which is better than most of the 10811A variants, but the phase noise isn't as good as other versions (like the -60258 you have). John ----- John Miles said the following on 08/08/2008 06:23 PM: > I don't have any of the 10811-60158s, but I did buy two of the 10811-60168s > that were up for auction recently. The -60168s seem to be really good > performers (from memory, -106 dBc/Hz at 1 Hz, -139 at 10, -155 at 100, -164 > at 1000, when I measured them against each other.) I have never seen any > specs for them, or anything else about them. > > If someone wants to lend one of the -60158s to me, I'll benchmark it against > one of the -60268s. > > Tom or JohnA, have either of you run any Allan plots on a 10811-60268? I'd > be curious to see how they do. From richard at karlquist.com Fri Aug 8 19:02:19 2008 From: richard at karlquist.com (Rick Karlquist) Date: Fri, 8 Aug 2008 16:02:19 -0700 (PDT) Subject: [time-nuts] Double-Oven Thunderbolt on Ebay In-Reply-To: <489CC91C.3060604@febo.com> References: <489CC91C.3060604@febo.com> Message-ID: <21579.192.25.142.225.1218236539.squirrel@webmail.sonic.net> John Ackermann N8UR wrote: > > One thing to note -- good phase noise and good ADEV don't necessarily go > together. Case in point is the -60158s are spec'd at 1x10e-12 at 1 > second, which is better than most of the 10811A variants, but the phase > noise isn't as good as other versions (like the -60258 you have). > > John Yes, in fact, they have almost nothing to do with each other. Short term stability at 1 second is determined entirely by the crystal and phase noise at 1 kHz is determined almost entirely by the circuit. This is in the 10811 or any decent oscillator. Of course it is possible to use a poorly designed circuit that degrades the 1 s stability (or a really bad oven). And a crystal of much lower Q or higher intrinisic phase noise might affect phase noise. But in practice in the 10811, absent pathological corner cases, what I originally said is accuracy AFAIK. Rick Karlquist N6RK From TheInfamousFlavio at hotmail.com Fri Aug 8 19:17:11 2008 From: TheInfamousFlavio at hotmail.com (TheInfamousFlavio at hotmail.com) Date: Fri, 8 Aug 2008 19:17:11 -0400 Subject: [time-nuts] Double-Oven Thunderbolt on Ebay References: Message-ID: I was actually talking about this one... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200243779655 not the the HP double ovens. -Flavio From jmiles at pop.net Fri Aug 8 20:29:26 2008 From: jmiles at pop.net (John Miles) Date: Fri, 8 Aug 2008 17:29:26 -0700 Subject: [time-nuts] Double-Oven Thunderbolt on Ebay In-Reply-To: Message-ID: > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of TheInfamousFlavio at hotmail.com > Sent: Friday, August 08, 2008 4:17 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Double-Oven Thunderbolt on Ebay > > > I was actually talking about this one... > > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200243779655 > > > not the the HP double ovens. Ah, sorry, my mistake; I was still thinking about those HP oscillators sold by the guy in China. I don't know about these double-oven units, but I will say that the OCXO in the TAPR Thunderbolts is extremely good, about 20 dB quieter at the 1-Hz timescale than the one in my (several-year-old) original Thunderbolt. -- john, KE5FX From louie at transsys.com Sat Aug 9 13:43:21 2008 From: louie at transsys.com (Louis Mamakos) Date: Sat, 9 Aug 2008 13:43:21 -0400 Subject: [time-nuts] The name "Totally Accurate Clock" In-Reply-To: <4898C1B7.4050004@verizon.net> References: <4898C1B7.4050004@verizon.net> Message-ID: <6C103FB8-6FE4-4EC8-9A83-2871C6D217CC@transsys.com> On Aug 5, 2008, at 5:10 PM, Tom Clark, K3IO wrote: > > My simple timing receiver was already producing sub-usec results > using > Motorola's PVT-6 "Six-Pack" 6-channel receiver, even in the face of > Selective Availability (SA). I think it was the "Six-Gun" receiver; I recall at the time while I was at U of MD, and we were doing some early NTP work, we bought a couple of PVT-6 receivers and "Six Gun" seems to ring a bell.. louie wa3ymh From jra at febo.com Sat Aug 9 16:27:59 2008 From: jra at febo.com (John Ackermann N8UR) Date: Sat, 09 Aug 2008 16:27:59 -0400 Subject: [time-nuts] TBolt and Z3801A performance data Message-ID: <489DFDCF.8060408@febo.com> I just put the results of some tests of 2 "Time-Nuts Special" Thunderbolts, as well as 2 Z3801As, at http://www.febo.com/pages/gpsdo_comparison/ I learned an interesting (and important) lesson in doing these measurement. I initially measured the pairs of GPSDO against each other (e.g., one TBolt as "reference" and the other TBolt as "DUT"). In theory, if the two oscillators are identical, and if their noise is uncorrelated, the results of the pair can be used to deduce the results of the individual units. However, in this case doing so gave a very optimistic view -- the TBolts were better than the pair of Z3801As! Another set of measurements comparing the GPSDOs against an independent reference revealed that the first measurement was a lie. I guess you can think of it like this. Picture two OCXOs that both age at the same rate and in the same direction. Because they drift together, measuring their relative phase hides their actual drift and makes them look better than they are. On the other hand, if they were drifting in opposite directions, they would look worse than they are. An identical aging trend is a "correlation" even though it's external to the things we usually think of. John From alan.melia at btinternet.com Sat Aug 9 17:15:55 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Sat, 9 Aug 2008 22:15:55 +0100 Subject: [time-nuts] GPS shielding by power lines? Message-ID: <001601c8fa65$1fc4ef20$0900a8c0@AM> Hi all, in the process of setting up a GPS time standard for a Radio Astronomy facility (amateur) we installed a GPS receiver in a small cabin with a translucent roof, thinking that would not impede the GPS signal. After a lot of head scratching as to why we were not getting the performane we got at another site, we realised that the "convenient position" for the cabin was directly below a three phase 11kV power distribution line ( common UK rural electricity distribution system). We extended the cable and moved the antenna about 20 - 30 feet to the side of the line run, which was mounted on wooden poles at about 25 feet. In this position we immediately got a reliable fix. The fix and number of usable satellites degrades as we move nearer the lines. The thought was that there as interference arcing or corona noise from the line insulators, and a receiver (AM) was deployed to listen for what was expected to be a substantial wide band noise signal....we didnt hear one! We are now confused about what the effect is. The signal could not be "screened" by the wires which are about 3 feet apart, but they definite provide a cone of interference directly under the run. The experiment was later repeated with two further different GPS receivers and produced the same result. Has anyone seen this before? have you any idea of what level noise we should be looking for? I believe this is a wide signal so maybe an AM receiver is not the best choice The area is a rural, horticultural area (called market garden in the UK) We are obviouslt concerned to trace any noise sources in the vicinity of the Hydrogen line frequency at 1420MHz. Alan G3NYK From magnus at rubidium.dyndns.org Sat Aug 9 17:28:15 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 09 Aug 2008 23:28:15 +0200 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <001601c8fa65$1fc4ef20$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> Message-ID: <489E0BEF.3070205@rubidium.dyndns.org> Alan Melia wrote: > Hi all, in the process of setting up a GPS time standard for a Radio > Astronomy facility (amateur) we installed a GPS receiver in a small cabin > with a translucent roof, thinking that would not impede the GPS signal. > After a lot of head scratching as to why we were not getting the performane > we got at another site, we realised that the "convenient position" for the > cabin was directly below a three phase 11kV power distribution line ( common > UK rural electricity distribution system). We extended the cable and moved > the antenna about 20 - 30 feet to the side of the line run, which was > mounted on wooden poles at about 25 feet. In this position we immediately > got a reliable fix. The fix and number of usable satellites degrades as we > move nearer the lines. > > The thought was that there as interference arcing or corona noise from the > line insulators, and a receiver (AM) was deployed to listen for what was > expected to be a substantial wide band noise signal....we didnt hear one! We > are now confused about what the effect is. The signal could not be > "screened" by the wires which are about 3 feet apart, but they definite > provide a cone of interference directly under the run. The experiment was > later repeated with two further different GPS receivers and produced the > same result. > > Has anyone seen this before? have you any idea of what level noise we should > be looking for? I believe this is a wide signal so maybe an AM receiver is > not the best choice The area is a rural, horticultural area (called market > garden in the UK) We are obviouslt concerned to trace any noise sources in > the vicinity of the Hydrogen line frequency at 1420MHz. It can also be a very simple case of strong multipath causing cancelation reflections strong enought to obscure the signal. Be sure to plot signal strength and if possible delta distance from solution for each satellite along with elevation and azimuth. See if a clear pattern emerges such that certain angles is problematic. Just to make you look in another direction. Cheers, Magnus From jmiles at pop.net Sat Aug 9 17:41:45 2008 From: jmiles at pop.net (John Miles) Date: Sat, 9 Aug 2008 14:41:45 -0700 Subject: [time-nuts] TBolt and Z3801A performance data In-Reply-To: <489DFDCF.8060408@febo.com> Message-ID: These tests were made with the GPS antenna connected? At t >> 100 seconds, they should all look about the same, because that's where GPS disciplining comes in, no? They should not be uncorrelated in the long run. To the extent one Z3801 looks worse than the other at large values of tau, I'd expect there to be a good reason, like better GPS reception on one of them, or a much-worse OCXO. Measuring phase noise by comparing the two against each other should be fine, though, since their short-term drift isn't being corrected at that timescale. Your noise floor is a couple dB worse than the one I tested, but they're otherwise about the same. - john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of John Ackermann N8UR > Sent: Saturday, August 09, 2008 1:28 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] TBolt and Z3801A performance data > > > I just put the results of some tests of 2 "Time-Nuts Special" > Thunderbolts, as well as 2 Z3801As, at > http://www.febo.com/pages/gpsdo_comparison/ > > I learned an interesting (and important) lesson in doing these > measurement. I initially measured the pairs of GPSDO against each other > (e.g., one TBolt as "reference" and the other TBolt as "DUT"). In > theory, if the two oscillators are identical, and if their noise is > uncorrelated, the results of the pair can be used to deduce the results > of the individual units. > > However, in this case doing so gave a very optimistic view -- the TBolts > were better than the pair of Z3801As! Another set of measurements > comparing the GPSDOs against an independent reference revealed that the > first measurement was a lie. > > I guess you can think of it like this. Picture two OCXOs that both age > at the same rate and in the same direction. Because they drift > together, measuring their relative phase hides their actual drift and > makes them look better than they are. On the other hand, if they were > drifting in opposite directions, they would look worse than they are. > An identical aging trend is a "correlation" even though it's external to > the things we usually think of. > > John From pieter.ibelings at gmail.com Sat Aug 9 17:47:35 2008 From: pieter.ibelings at gmail.com (Pieter Ibelings) Date: Sat, 9 Aug 2008 17:47:35 -0400 Subject: [time-nuts] TBolt References: <489DFDCF.8060408@febo.com> Message-ID: <2CAF98B5F7044BACB9F9F317E029AEDE@xps> Hi, Where can I purchase one or two of the time-nuts Tbolt specials? Thanks, Pieter ----- Original Message ----- From: "John Ackermann N8UR" To: "Discussion of precise time and frequency measurement" Sent: Saturday, August 09, 2008 4:27 PM Subject: [time-nuts] TBolt and Z3801A performance data >I just put the results of some tests of 2 "Time-Nuts Special" > Thunderbolts, as well as 2 Z3801As, at > http://www.febo.com/pages/gpsdo_comparison/ > > I learned an interesting (and important) lesson in doing these > measurement. I initially measured the pairs of GPSDO against each other > (e.g., one TBolt as "reference" and the other TBolt as "DUT"). In > theory, if the two oscillators are identical, and if their noise is > uncorrelated, the results of the pair can be used to deduce the results > of the individual units. > > However, in this case doing so gave a very optimistic view -- the TBolts > were better than the pair of Z3801As! Another set of measurements > comparing the GPSDOs against an independent reference revealed that the > first measurement was a lie. > > I guess you can think of it like this. Picture two OCXOs that both age > at the same rate and in the same direction. Because they drift > together, measuring their relative phase hides their actual drift and > makes them look better than they are. On the other hand, if they were > drifting in opposite directions, they would look worse than they are. > An identical aging trend is a "correlation" even though it's external to > the things we usually think of. > > 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 jra at febo.com Sat Aug 9 17:48:37 2008 From: jra at febo.com (John Ackermann N8UR) Date: Sat, 09 Aug 2008 17:48:37 -0400 Subject: [time-nuts] TBolt and Z3801A performance data In-Reply-To: References: Message-ID: <489E10B5.5040104@febo.com> Yes, all were made with GPS antenna connected (and running from the same antenna via an 8-port splitter). What I was mainly commenting on is the TBolt's pronounced "hump" that shows up in the measurements against the FTS-1050A but largely disappears in the pairwise measurement. The longer tau readings are interesting mainly to see how the GPS loop kicks in; tau below about 1000 seconds seem related to OCXO performance on the TBolts, while the Z3801A seems to have a longer time constant, and somewhat more gradual attack. (By the way -- the TBolts were running with the loop parameters they were set to when I got them). John ---- John Miles said the following on 08/09/2008 05:41 PM: > These tests were made with the GPS antenna connected? At t >> 100 seconds, > they should all look about the same, because that's where GPS disciplining > comes in, no? They should not be uncorrelated in the long run. > > To the extent one Z3801 looks worse than the other at large values of tau, > I'd expect there to be a good reason, like better GPS reception on one of > them, or a much-worse OCXO. > > Measuring phase noise by comparing the two against each other should be > fine, though, since their short-term drift isn't being corrected at that > timescale. Your noise floor is a couple dB worse than the one I tested, but > they're otherwise about the same. > > - john, KE5FX > > >> -----Original Message----- >> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On >> Behalf Of John Ackermann N8UR >> Sent: Saturday, August 09, 2008 1:28 PM >> To: Discussion of precise time and frequency measurement >> Subject: [time-nuts] TBolt and Z3801A performance data >> >> >> I just put the results of some tests of 2 "Time-Nuts Special" >> Thunderbolts, as well as 2 Z3801As, at >> http://www.febo.com/pages/gpsdo_comparison/ >> >> I learned an interesting (and important) lesson in doing these >> measurement. I initially measured the pairs of GPSDO against each other >> (e.g., one TBolt as "reference" and the other TBolt as "DUT"). In >> theory, if the two oscillators are identical, and if their noise is >> uncorrelated, the results of the pair can be used to deduce the results >> of the individual units. >> >> However, in this case doing so gave a very optimistic view -- the TBolts >> were better than the pair of Z3801As! Another set of measurements >> comparing the GPSDOs against an independent reference revealed that the >> first measurement was a lie. >> >> I guess you can think of it like this. Picture two OCXOs that both age >> at the same rate and in the same direction. Because they drift >> together, measuring their relative phase hides their actual drift and >> makes them look better than they are. On the other hand, if they were >> drifting in opposite directions, they would look worse than they are. >> An identical aging trend is a "correlation" even though it's external to >> the things we usually think of. >> >> 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 bg at lysator.liu.se Sat Aug 9 17:59:05 2008 From: bg at lysator.liu.se (=?ISO-8859-1?Q?Bj=F6rn?= Gabrielsson) Date: Sat, 09 Aug 2008 23:59:05 +0200 Subject: [time-nuts] TBolt and Z3801A performance data In-Reply-To: <489E10B5.5040104@febo.com> References: <489E10B5.5040104@febo.com> Message-ID: <1218319145.7397.114.camel@bg-desktop> Hi John, On Sat, 2008-08-09 at 17:48 -0400, John Ackermann N8UR wrote: > The longer tau readings are interesting mainly to see how the GPS loop > kicks in; tau below about 1000 seconds seem related to OCXO performance > on the TBolts, while the Z3801A seems to have a longer time constant, > and somewhat more gradual attack. (By the way -- the TBolts were > running with the loop parameters they were set to when I got them). > > John Would the fact that the bump is that "big" indicate that a more "aggressive" loop parameter setup would improve those two individual units performance? -- Bj?rn From jmiles at pop.net Sat Aug 9 18:10:56 2008 From: jmiles at pop.net (John Miles) Date: Sat, 9 Aug 2008 15:10:56 -0700 Subject: [time-nuts] TBolt and Z3801A performance data In-Reply-To: <1218319145.7397.114.camel@bg-desktop> Message-ID: > Hi John, > > On Sat, 2008-08-09 at 17:48 -0400, John Ackermann N8UR wrote: > > > The longer tau readings are interesting mainly to see how the GPS loop > > kicks in; tau below about 1000 seconds seem related to OCXO performance > > on the TBolts, while the Z3801A seems to have a longer time constant, > > and somewhat more gradual attack. (By the way -- the TBolts were > > running with the loop parameters they were set to when I got them). > > > > John > > Would the fact that the bump is that "big" indicate that a more > "aggressive" loop parameter setup would improve those two individual > units performance? It would be an interesting thing to try. The default loop bandwidth is 0.01 Hz, but since the peak of the hump is right there too, I'm not sure if GPS or the OCXO is responsible for it. The OCXO could be relatively stable at a 100-second scale but dragged around inappropriately by the GPS receiver, or the OCXO could be relatively unstable and corrected too slowly by the GPS receiver. It looks like HP uses a much lower loop bandwidth. Even so, it's interesting that we see no hint of convergence between the two GPS-locked HP oscillators at longer timescales. It's unfortunate that this kind of test takes so long to run, because it's the sort of thing you need to repeat several times to make sure you're getting at the truth of the matter. -- john, KE5FX From smace at intt.net Sat Aug 9 18:40:37 2008 From: smace at intt.net (Scott Mace) Date: Sat, 09 Aug 2008 17:40:37 -0500 Subject: [time-nuts] Thunderbolt PPS output Message-ID: <489E1CE5.3050904@intt.net> Has anyone used the thunderbolt PPS output with a N8UR FatPPS? I'm seeing a large (+-100-300us) amount of jitter on the output of the FatPPS. This same setup works fine with the input from z3801a (using a PECL/TTL converter) or the Fury (even though the Fury's pulse is wide enough to begin with). Is there something special about the thunderbolt PPS output? I noticed it seemed to require 50ohm termination to get a clean signal when I connected it to a counter (5334a) with a 3 foot cable. I'm using the FatPPS in conjunction with a soekris 4501 with the tmrin mod. Scott From didier at cox.net Sat Aug 9 19:14:59 2008 From: didier at cox.net (Didier Juges) Date: Sat, 9 Aug 2008 18:14:59 -0500 Subject: [time-nuts] Thunderbolt PPS output In-Reply-To: <489E1CE5.3050904@intt.net> References: <489E1CE5.3050904@intt.net> Message-ID: <01d001c8fa75$bf708880$04000100@didierhp> The TB's PPS output has something like 5 ohm output impedance. It is very desirable to terminate the coax cable with 50 ohm at the other end, otherwise you will get endless ringing The following web page uses the PPS output of the Thunderbolt to illustrate ringing in a non-matched cable: http://www.ko4bb.com/Test_Equipment/CoaxCableMatching.php And this page shows a minimum, energy efficient pulse stretcher: http://www.ko4bb.com/Test_Equipment/Thunderbolt/PulseStretching/ Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Scott Mace > Sent: Saturday, August 09, 2008 5:41 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Thunderbolt PPS output > > Has anyone used the thunderbolt PPS output with a N8UR > FatPPS? I'm seeing a large (+-100-300us) amount of jitter on > the output of the FatPPS. This same setup works fine with > the input from z3801a (using a PECL/TTL converter) or the > Fury (even though the Fury's pulse is wide enough to begin with). > Is there something special about the thunderbolt PPS output? > I noticed it seemed to require 50ohm termination to get a > clean signal when I connected it to a counter (5334a) with a > 3 foot cable. > > I'm using the FatPPS in conjunction with a soekris 4501 with > the tmrin mod. > > Scott > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com To unsubscribe, > go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. From pieter.ibelings at gmail.com Sat Aug 9 23:49:12 2008 From: pieter.ibelings at gmail.com (Pieter Ibelings) Date: Sat, 9 Aug 2008 23:49:12 -0400 Subject: [time-nuts] Z3801A References: <489E1CE5.3050904@intt.net> <01d001c8fa75$bf708880$04000100@didierhp> Message-ID: <6BAC7B1B0681496C9E011C6B43E50FE9@xps> Hi all, I am reviving an old Z3801A that was stored for 5 years. I did the RS232 header mod and I can communicate with the unit. The power LED does not come on, but I can control the enabled and active LED. I am not able to enter a date after 2007 to speed up the adquisition process. Is there a new firmware that I can load? Anyone heard of LED problems? There are no alarms in the status window. Regards, Pieter, N4IP From tractorb at ihug.co.nz Sun Aug 10 01:30:34 2008 From: tractorb at ihug.co.nz (Dave Brown) Date: Sun, 10 Aug 2008 17:30:34 +1200 Subject: [time-nuts] Power supply for Thunderbolt References: Message-ID: <014201c8faaa$387ed680$7900a8c0@athlon1200> ----- Original Message ----- From: "John Miles" To: "Discussion of precise time and frequency measurement" Sent: Friday, August 08, 2008 1:21 AM Subject: Re: [time-nuts] Power supply for Thunderbolt > >> >> It would be interesting to see how the 'red panel' Thunderbolts >> (the >> packaged type that run from an included switching supply fed from >> 24 >> VDC) perform under a test regime such as that TVB used to compare >> various three rail power supplies. In 'distant past' posts, maybe >> 18 >> months back, it was suggested that this supply is a particularly >> good >> performer, but IIRC no data was supplied to support this statement. >> Anyone able to oblige? > > This (cluttered) graph is indicative of the results I've seen. The > Lucent > supply used in the older red-and-black labelled Thunderbolts was not > very > clean, and its proximity and orientation adjacent to the > Thunderbolt's PCB > didn't help. > > Red = the new ("TAPR") Thunderbolt with my old Thunderbolt's Lucent > supply > Blue = the old Thunderbolt with its Lucent supply > Orange = the new Thunderbolt with the supply Tom chose > Purple = the old Thunderbolt with Tom's supply > > The reference for the red trace was somewhat noisier below 100 Hz > than the > one used for the others. You should assume that the red trace > coincides > with the orange one below 100 Hz. > > -- john, KE5FX Tnx John-looks like the included power supply was not a great performer in this regard. DaveB, NZ From ka2cdk at cox.net Sun Aug 10 01:38:20 2008 From: ka2cdk at cox.net (Thomas A. Frank) Date: Sun, 10 Aug 2008 01:38:20 -0400 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <001601c8fa65$1fc4ef20$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> Message-ID: > The thought was that there as interference arcing or corona noise > from the > line insulators, and a receiver (AM) was deployed to listen for > what was > expected to be a substantial wide band noise signal....we didnt > hear one! We > are now confused about what the effect is. The signal could not be > "screened" by the wires which are about 3 feet apart, but they > definite > provide a cone of interference directly under the run. The > experiment was > later repeated with two further different GPS receivers and > produced the > same result. > > Has anyone seen this before? have you any idea of what level noise > we should > be looking for? I believe this is a wide signal so maybe an AM > receiver is > not the best choice The area is a rural, horticultural area (called > market > garden in the UK) We are obviouslt concerned to trace any noise > sources in > the vicinity of the Hydrogen line frequency at 1420MHz. > > Alan G3NYK Alan; I have no idea if this is a cause of your problem, but in some work I have done, I found that the high field strengths (electrostatic and magnetic) found under power lines can adversely effect electronic equipment that should otherwise be unaffected by the presence of power lines and their low frequency signals. I would imagine that the fields could desensitize receivers by overloading the front end amplifiers, and no amount of filtering is going to help because it is virtually impossible to shield against 50/60 Hz signals. A solid steel conduit several mm thick is only good for about 27 dB attenuation at power line frequencies. Fortunately, distance makes things better, so you may just have to move everything a bit away from the power lines. Our solution was to digitize our signals several hundred meters from the power lines and send the results digitally past them. Try getting a field strength meter (gaussmeter) and see what levels you have under the lines. Tom Frank, KA2CDK From dave.g0dja at tiscali.co.uk Sun Aug 10 03:30:11 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 10 Aug 2008 08:30:11 +0100 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <001601c8fa65$1fc4ef20$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> Message-ID: <489E9903.90901@tiscali.co.uk> Alan Melia wrote: > Hi all, in the process of setting up a GPS time standard for a Radio > Astronomy facility (amateur) we installed a GPS receiver in a small cabin > with a translucent roof, thinking that would not impede the GPS signal. > After a lot of head scratching as to why we were not getting the performane > we got at another site, we realised that the "convenient position" for the > cabin was directly below a three phase 11kV power distribution line ( common > UK rural electricity distribution system). Since the satellite signals are in the high UHF range, arround 1575MHz, the AM receiver test is not going to tell you alot about the noise at the frequency that the GPS receiver is using. So, even if you had detected any noise from the overhead lines, it might not have been proof that this was the cause of the problems. I find that the positioning of the antenna for a GPS receiver can be very touchy. You really need a good view to the horizon and, despite what you might see on simple presentations of the satellite positions, they do tend to be mainly in the southern sky when viewed from the UK. See http://www.guralp.com/articles/20060405-howto-gps-troubleshooting/print for details. The other effect that you may notice is that your 'good' position for the antenna isn't so good all of the time as the satellites appear to move round the sky and the signal strengths from each alters. Dave (G0DJA) From alan.melia at btinternet.com Sun Aug 10 05:12:09 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Sun, 10 Aug 2008 10:12:09 +0100 Subject: [time-nuts] GPS shielding by power lines? References: <001601c8fa65$1fc4ef20$0900a8c0@AM> <489E9903.90901@tiscali.co.uk> Message-ID: <003101c8facb$82f29460$0900a8c0@AM> Hi Dave, Ah I meant a 1600Mhz AM RX not a MW job the resuly is quite dramatic from seeing no usable satelites to seeing 10 to 12. The software we are running plots the tracks of the those sats seen so we can see that when seen even close to trees, foliage shielding is not a problem. I could post this plot over a number of hours it is "very pretty", and shows clearly the northerly extent of the orbits very clearly. Thanks Magnus for thoughts on further tests. We are logging the NMEA sentences so most of that detail could be available. A job for a laptop I think. Alan G3NYK ----- Original Message ----- From: "David Ackrill" To: "Discussion of precise time and frequency measurement" Sent: Sunday, August 10, 2008 8:30 AM Subject: Re: [time-nuts] GPS shielding by power lines? > Alan Melia wrote: > > Hi all, in the process of setting up a GPS time standard for a Radio > > Astronomy facility (amateur) we installed a GPS receiver in a small cabin > > with a translucent roof, thinking that would not impede the GPS signal. > > After a lot of head scratching as to why we were not getting the performane > > we got at another site, we realised that the "convenient position" for the > > cabin was directly below a three phase 11kV power distribution line ( common > > UK rural electricity distribution system). > > Since the satellite signals are in the high UHF range, arround 1575MHz, > the AM receiver test is not going to tell you alot about the noise at > the frequency that the GPS receiver is using. So, even if you had > detected any noise from the overhead lines, it might not have been proof > that this was the cause of the problems. > > I find that the positioning of the antenna for a GPS receiver can be > very touchy. You really need a good view to the horizon and, despite > what you might see on simple presentations of the satellite positions, > they do tend to be mainly in the southern sky when viewed from the UK. > > See > http://www.guralp.com/articles/20060405-howto-gps-troubleshooting/print > for details. > > The other effect that you may notice is that your 'good' position for > the antenna isn't so good all of the time as the satellites appear to > move round the sky and the signal strengths from each alters. > > Dave (G0DJA) > > _______________________________________________ > time-nuts mailing list -- 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 alan.melia at btinternet.com Sun Aug 10 05:27:31 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Sun, 10 Aug 2008 10:27:31 +0100 Subject: [time-nuts] GPS shielding by power lines? References: <001601c8fa65$1fc4ef20$0900a8c0@AM> Message-ID: <003301c8facb$847319e0$0900a8c0@AM> Hi Tom Brilliant I hadnt thought of the fields actually affecting the operation of the electronics! that is certainly something that might be interesting to check. I note there lines have three "phase" feeds but no neutral wire so they must use ground as the return path to any unbalance currents.(?) Thanks Alan G3NYK ----- Original Message ----- From: "Thomas A. Frank" To: "Discussion of precise time and frequency measurement" Sent: Sunday, August 10, 2008 6:38 AM Subject: Re: [time-nuts] GPS shielding by power lines? > Alan; > > I have no idea if this is a cause of your problem, but in some work I > have done, I found that the high field strengths (electrostatic and > magnetic) found under power lines can adversely effect electronic > equipment that should otherwise be unaffected by the presence of > power lines and their low frequency signals. there. ----------snip From didier at cox.net Sun Aug 10 07:52:55 2008 From: didier at cox.net (Didier Juges) Date: Sun, 10 Aug 2008 06:52:55 -0500 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <003301c8facb$847319e0$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> <003301c8facb$847319e0$0900a8c0@AM> Message-ID: <01f201c8fadf$a0f57130$04000100@didierhp> Alan, I don't believe you have said what type of antenna you are using. If you are using a true timing antenna (Symmetricom, Trimble Bullet) I would expect little or no direct effect from the power lines, but if you are using a puck or other inexpensive commercial antenna (which have little or no filtering or shielding), you may well be affected directly by the field from the power line on the antenna itself. The Thunderbolt itself should have enough filtering to protect you from a direct effect, the Thunderbolt has been designed to be co-located with other equipment, particularly cell transmitters, so I would expect it to be fairly immune to stray fields. Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Alan Melia > Sent: Sunday, August 10, 2008 4:28 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] GPS shielding by power lines? > > Hi Tom Brilliant I hadnt thought of the fields actually > affecting the operation of the electronics! that is certainly > something that might be interesting to check. I note there > lines have three "phase" feeds but no neutral wire so they > must use ground as the return path to any unbalance > currents.(?) > > Thanks Alan G3NYK > ----- Original Message ----- > From: "Thomas A. Frank" > To: "Discussion of precise time and frequency measurement" > > Sent: Sunday, August 10, 2008 6:38 AM > Subject: Re: [time-nuts] GPS shielding by power lines? > > > > Alan; > > > > I have no idea if this is a cause of your problem, but in > some work I > > have done, I found that the high field strengths (electrostatic and > > magnetic) found under power lines can adversely effect electronic > > equipment that should otherwise be unaffected by the > presence of power > > lines and their low frequency signals. > there. > ----------snip > > > _______________________________________________ > time-nuts mailing list -- 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 Sun Aug 10 07:53:40 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Sun, 10 Aug 2008 13:53:40 +0200 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <003301c8facb$847319e0$0900a8c0@AM> Message-ID: On Sun, 10 Aug 2008 10:27:31 +0100, Alan Melia wrote: >.... I note there lines have three "phase" feeds but no >neutral wire so they must use ground as the return path to any unbalance >currents.(?) As long as the system is kept balanced a 3 phase energy transport system does not need a 4th wire as the sum of all the currents in the 3 wires (phase shift 120deg between the wires) is zero! regards Arnold, DK2WT From dave.g0dja at tiscali.co.uk Sun Aug 10 08:01:48 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 10 Aug 2008 13:01:48 +0100 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <003301c8facb$847319e0$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> <003301c8facb$847319e0$0900a8c0@AM> Message-ID: <489ED8AC.5000903@tiscali.co.uk> Alan Melia wrote: > Hi Tom Brilliant I hadnt thought of the fields actually affecting the > operation of the electronics! that is certainly something that might be > interesting to check. I note there lines have three "phase" feeds but no > neutral wire so they must use ground as the return path to any unbalance > currents.(?) On the UK 11kV overhead network the phases are all distributed without a neutral. At the 11kV/415V transformer the HV side is delta wound and the LV is star wound, so the neutral/earth for the supply is taken from that point, not from the HV side. So, you are correct, the connection to "the general mass of earth" at the transformers is used as the return path. Which is why there are regulations about the acceptable earthing impedances at HV/LV transformers on an overhead supply. Tales of Linesmen watering earth rods to get away without having to drive in more earth rods and connect up to the transformers, and so avoid having to drive rods into hard ground, are legion in the ESI... In fact, if you look at most of the overhead high voltage distribution systems, they are all phase only, no neutral... Dave (G0DJA) From dave.g0dja at tiscali.co.uk Sun Aug 10 08:05:47 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 10 Aug 2008 13:05:47 +0100 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: References: Message-ID: <489ED99B.5020803@tiscali.co.uk> Arnold Tibus wrote: > As long as the system is kept balanced a 3 phase energy transport > system does not need a 4th wire as the sum of all the currents in the 3 wires > (phase shift 120deg between the wires) is zero! > regards > Arnold, DK2WT That is true Arnold, but in the UK (and in some other countries) we don't always have a completely balanced load. There are cases where two phase 11kV lines are run out to farms and other rural houses and, often the equipment connected at the farm/rural supplies isn't properly balanced either. The unbalanced current is connected to earth at the HV/LV transformer, as described previously. :-) Probably getting a bit OT now... Dave (G0DJA) From phk at phk.freebsd.dk Sun Aug 10 08:20:05 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Sun, 10 Aug 2008 12:20:05 +0000 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: Your message of "Sun, 10 Aug 2008 06:52:55 EST." <01f201c8fadf$a0f57130$04000100@didierhp> Message-ID: <3824.1218370805@critter.freebsd.dk> Around all high voltage lines the air is somewhat ionized and this may result in sufficient free electrons to seriously mess up the GPS signal, although I wouldn't expect much trouble from a 11kV line. The fact that the navigation message is 50Hz in the GPS signal and the power-grid in the UK is "close to 50Hz" is not a good thing in any case. -- 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 dave.g0dja at tiscali.co.uk Sun Aug 10 08:33:03 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 10 Aug 2008 13:33:03 +0100 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <3824.1218370805@critter.freebsd.dk> References: <3824.1218370805@critter.freebsd.dk> Message-ID: <489EDFFF.1050508@tiscali.co.uk> Poul-Henning Kamp wrote: > The fact that the navigation message is 50Hz in the GPS signal and > the power-grid in the UK is "close to 50Hz" is not a good thing > in any case. By UK law, it must be within +/- 1% of 50Hz. :-) Dave (G0DJA) From alan.melia at btinternet.com Sun Aug 10 09:16:31 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Sun, 10 Aug 2008 14:16:31 +0100 Subject: [time-nuts] GPS shielding by power lines? References: <001601c8fa65$1fc4ef20$0900a8c0@AM><003301c8facb$847319e0$0900a8c0@AM> <01f201c8fadf$a0f57130$04000100@didierhp> Message-ID: <007f01c8faec$55aebd00$0900a8c0@AM> Hi Didier, thanks for that idea, yes they were all "pucks" all Garmin two intended for marine use and one was a old Garmin GPSIIplus with a mag "puck". I have a Trimble Palisade that I have not got round to working on yet, but I understand that there are problems putting this version into NMEA mode...so will have to be careful. Thanks Alan G3NYK ----- Original Message ----- From: "Didier Juges" To: "'Discussion of precise time and frequency measurement'" Sent: Sunday, August 10, 2008 12:52 PM Subject: Re: [time-nuts] GPS shielding by power lines? > Alan, > > I don't believe you have said what type of antenna you are using. If you are > using a true timing antenna (Symmetricom, Trimble Bullet) I would expect > little or no direct effect from the power lines, but if you are using a puck > or other inexpensive commercial antenna (which have little or no filtering > or shielding), you may well be affected directly by the field from the power > line on the antenna itself. The Thunderbolt itself should have enough > filtering to protect you from a direct effect, the Thunderbolt has been > designed to be co-located with other equipment, particularly cell > transmitters, so I would expect it to be fairly immune to stray fields. > > Didier KO4BB From dave.g0dja at tiscali.co.uk Sun Aug 10 09:37:32 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 10 Aug 2008 14:37:32 +0100 Subject: [time-nuts] Trimble Palisade (Was - GPS shielding by power lines?) In-Reply-To: <007f01c8faec$55aebd00$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM><003301c8facb$847319e0$0900a8c0@AM> <01f201c8fadf$a0f57130$04000100@didierhp> <007f01c8faec$55aebd00$0900a8c0@AM> Message-ID: <489EEF1C.10002@tiscali.co.uk> Alan Melia wrote: > Hi Didier, thanks for that idea, yes they were all "pucks" all Garmin two > intended for marine use and one was a old Garmin GPSIIplus with a mag > "puck". I have a Trimble Palisade that I have not got round to working on > yet, but I understand that there are problems putting this version into NMEA > mode...so will have to be careful. > The advice I was given when I got mine was *not* to try to put the unit into NMEA mode, as it changes the communication settings and you cannot change them back, nor can you communicate with the unit after you have done it! See http://www.dc2light.pwp.blueyonder.co.uk/Webpage/ The advice seems to be to build an additional circuit to take the output from the Palisade and convert that to NMEA. Dave (G0DJA) From phk at phk.freebsd.dk Sun Aug 10 09:46:45 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Sun, 10 Aug 2008 13:46:45 +0000 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: Your message of "Sun, 10 Aug 2008 13:33:03 +0100." <489EDFFF.1050508@tiscali.co.uk> Message-ID: <4413.1218376005@critter.freebsd.dk> In message <489EDFFF.1050508 at tiscali.co.uk>, David Ackrill writes: >Poul-Henning Kamp wrote: > >> The fact that the navigation message is 50Hz in the GPS signal and >> the power-grid in the UK is "close to 50Hz" is not a good thing >> in any case. > >By UK law, it must be within +/- 1% of 50Hz. :-) Yeah, but the fact that it wanders in short time would make it an excellent frustration for GPS signal locking. -- 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 didier at cox.net Sun Aug 10 09:51:50 2008 From: didier at cox.net (Didier Juges) Date: Sun, 10 Aug 2008 08:51:50 -0500 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <007f01c8faec$55aebd00$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM><003301c8facb$847319e0$0900a8c0@AM><01f201c8fadf$a0f57130$04000100@didierhp> <007f01c8faec$55aebd00$0900a8c0@AM> Message-ID: <020d01c8faf0$3d979b20$04000100@didierhp> Alan, I recommend you look for an HP 58532A. I bought a brand new one on eBay for $50 BIN, sometimes you can do better. This is a good timing-grade antenna, and intended to stay outside for a long time. They have good filtering and the LNA is shielded. Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Alan Melia > Sent: Sunday, August 10, 2008 8:17 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] GPS shielding by power lines? > > Hi Didier, thanks for that idea, yes they were all "pucks" > all Garmin two intended for marine use and one was a old > Garmin GPSIIplus with a mag "puck". I have a Trimble > Palisade that I have not got round to working on yet, but I > understand that there are problems putting this version into > NMEA mode...so will have to be careful. > > Thanks Alan G3NYK > > ----- Original Message ----- > From: "Didier Juges" > To: "'Discussion of precise time and frequency measurement'" > > Sent: Sunday, August 10, 2008 12:52 PM > Subject: Re: [time-nuts] GPS shielding by power lines? > > > > Alan, > > > > I don't believe you have said what type of antenna you are > using. If > > you > are > > using a true timing antenna (Symmetricom, Trimble Bullet) I would > > expect little or no direct effect from the power lines, but > if you are > > using a > puck > > or other inexpensive commercial antenna (which have little or no > > filtering or shielding), you may well be affected directly by the > > field from the > power > > line on the antenna itself. The Thunderbolt itself should > have enough > > filtering to protect you from a direct effect, the Thunderbolt has > > been designed to be co-located with other equipment, > particularly cell > > transmitters, so I would expect it to be fairly immune to > stray fields. > > > > Didier KO4BB > > > > _______________________________________________ > time-nuts mailing list -- 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 henk at deriesp.demon.nl Sun Aug 10 10:11:25 2008 From: henk at deriesp.demon.nl (Henk ten Pierick) Date: Sun, 10 Aug 2008 16:11:25 +0200 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <007f01c8faec$55aebd00$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM><003301c8facb$847319e0$0900a8c0@AM> <01f201c8fadf$a0f57130$04000100@didierhp> <007f01c8faec$55aebd00$0900a8c0@AM> Message-ID: <368A916B-C609-4BA9-99D6-10FF07152E07@deriesp.demon.nl> Hi, In car radio capacitive antennas are used. The required LNA rejection for the power line frequency is in the order of 100dB. henk On Aug 10, 2008, at 15:16, Alan Melia wrote: > Hi Didier, thanks for that idea, yes they were all "pucks" all > Garmin two > intended for marine use and one was a old Garmin GPSIIplus with a mag > "puck". I have a Trimble Palisade that I have not got round to > working on > yet, but I understand that there are problems putting this version > into NMEA > mode...so will have to be careful. > > Thanks Alan G3NYK > > ----- Original Message ----- > From: "Didier Juges" > To: "'Discussion of precise time and frequency measurement'" > > Sent: Sunday, August 10, 2008 12:52 PM > Subject: Re: [time-nuts] GPS shielding by power lines? > > >> Alan, >> >> I don't believe you have said what type of antenna you are using. >> If you > are >> using a true timing antenna (Symmetricom, Trimble Bullet) I would >> expect >> little or no direct effect from the power lines, but if you are >> using a > puck >> or other inexpensive commercial antenna (which have little or no >> filtering >> or shielding), you may well be affected directly by the field from >> the > power >> line on the antenna itself. The Thunderbolt itself should have enough >> filtering to protect you from a direct effect, the Thunderbolt has >> been >> designed to be co-located with other equipment, particularly cell >> transmitters, so I would expect it to be fairly immune to stray >> fields. >> >> Didier KO4BB > > > > _______________________________________________ > time-nuts mailing list -- 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 smace at intt.net Sun Aug 10 14:05:22 2008 From: smace at intt.net (Scott Mace) Date: Sun, 10 Aug 2008 13:05:22 -0500 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <001601c8fa65$1fc4ef20$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> Message-ID: <489F2DE2.6070504@intt.net> Around here they place cell antennas on a monopole down the center of power transmission line towers. The GPS antennas are invariably directly below the 100-200kv lines. The GPS signal must be reliable enough or the cell sites wouldn't be there. Scott Alan Melia wrote: > Hi all, in the process of setting up a GPS time standard for a Radio > Astronomy facility (amateur) we installed a GPS receiver in a small cabin > with a translucent roof, thinking that would not impede the GPS signal. > After a lot of head scratching as to why we were not getting the performane > we got at another site, we realised that the "convenient position" for the > cabin was directly below a three phase 11kV power distribution line ( common > UK rural electricity distribution system). We extended the cable and moved > the antenna about 20 - 30 feet to the side of the line run, which was > mounted on wooden poles at about 25 feet. In this position we immediately > got a reliable fix. The fix and number of usable satellites degrades as we > move nearer the lines. > > The thought was that there as interference arcing or corona noise from the > line insulators, and a receiver (AM) was deployed to listen for what was > expected to be a substantial wide band noise signal....we didnt hear one! We > are now confused about what the effect is. The signal could not be > "screened" by the wires which are about 3 feet apart, but they definite > provide a cone of interference directly under the run. The experiment was > later repeated with two further different GPS receivers and produced the > same result. > > Has anyone seen this before? have you any idea of what level noise we should > be looking for? I believe this is a wide signal so maybe an AM receiver is > not the best choice The area is a rural, horticultural area (called market > garden in the UK) We are obviouslt concerned to trace any noise sources in > the vicinity of the Hydrogen line frequency at 1420MHz. > > Alan G3NYK > > > _______________________________________________ > time-nuts mailing list -- 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 Sun Aug 10 16:00:57 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Sun, 10 Aug 2008 22:00:57 +0200 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <489ED99B.5020803@tiscali.co.uk> Message-ID: On Sun, 10 Aug 2008 13:05:47 +0100, David Ackrill wrote: >Arnold Tibus wrote: >> As long as the system is kept balanced a 3 phase energy transport >> system does not need a 4th wire as the sum of all the currents in the 3 wires >> (phase shift 120deg between the wires) is zero! >> regards >> Arnold, DK2WT >That is true Arnold, but in the UK (and in some other countries) we >don't always have a completely balanced load. >There are cases where two phase 11kV lines are run out to farms and >other rural houses and, often the equipment connected at the farm/rural >supplies isn't properly balanced either. >The unbalanced current is connected to earth at the HV/LV transformer, >as described previously. :-) David, I agree with the a.m. unbalance, but the current should not be routed via the ground! As you say, there is a connection to ground on the Y circuit of the secondary side towards the load. From this point on there are then 4 wires in use (L1, L2, L3, N). I repeat, the return current shall not be run via ground! (At the entry of a building the neutral or return wire will be grounded to avoid voltage differences. At this point the PE will be connected as well for protection purposes.) Ground currents are in general very problematic because the resulting severe corrosion effects and noise. As I am informed, the connections of hundreds of loads will (statistically) appear more or less as balanced at the end. Eventual still existing unsymmetries are to be compensated at the medium (10 to 20 kV) to end voltage (eg. 230/400V) using distribution transformers via tricky Z-winding connections. To avoid overvoltage due to unbalance and the floating of the HV-lines, the star point of the Y transformer at one end may be grounded for ground reference, on the other side of the line a overvoltage protector will be used instead of direct grounding. Ground currents are not possible this way. To eliminate such unbalances on the HV-lines there are possibilities to compensate with special symmetry compensator devices (a kind of transformers). Sorry, this was in effect somewhat off topic, but I didn't want to leave this point uncomplete... Now to the main concern and question: I believe the problem with the 'blind' GPS system may have other reasons. 1. Due to very fast changing loads and pulse like loads (switcher etc.) there are indeed some rf on the lines. Driving partly the hv-transformers into saturation does as well result in higher frequencies (fourier). The long lines do act as antennas... 2. The high and very high voltage lines do create very strong fields up to several kV/m and some ?T! To bring this fieldstrength significantly down one shall position the antenna at least 30 to 50m away from the center line. (35 years ago I did stop with my car directly below a 380 kV line. My feet on ground standing in the open door I put my hand on top the roof of the car - wow what a strong feeling touching that big capacitor plane 1.5 m above ground! ) I am sure, the strong fields below the power lines do create some distribution current in the soil. Perhaps specially patch antennas are very susceptable to such strong fields which may upset the amplfier shifting levels...? How strong are the rf fields from these lines being perhaps a factor of several thousands below the 50 Hz field strength? regards Arnold, DK2WT From smace at intt.net Sun Aug 10 16:42:02 2008 From: smace at intt.net (Scott Mace) Date: Sun, 10 Aug 2008 15:42:02 -0500 Subject: [time-nuts] thunderbolt for ntpd or gpsd In-Reply-To: <200806151159.45824.w.knowles@xtra.co.nz> References: <200806151159.45824.w.knowles@xtra.co.nz> Message-ID: <489F529A.1030700@intt.net> ntpshm_put() needs to be called in the 0xab case as well for ntp to work. Scott --- gpsd/trunk/tsip.c 2008-08-08 23:38:27.000000000 -0500 +++ ../gpsd/trunk/tsip.c 2008-08-09 04:14:09.000000000 -0500 @@ -65,7 +65,7 @@ /* XXX clever heuristic to decide if the parity change is required. */ session->driver.tsip.parity = session->gpsdata.parity; session->driver.tsip.stopbits = session->gpsdata.stopbits; - gpsd_set_speed(session, session->gpsdata.baudrate, 'O', 1); + gpsd_set_speed(session, session->gpsdata.baudrate, 'N', 1); break; case 1: @@ -674,6 +674,10 @@ session->gpsdata.fix.time = session->gpsdata.sentence_time = gpstime_to_unix((int)s1, f1) - (double)u1; +#ifdef NTPSHM_ENABLE + if (session->context->enable_ntpshm) + (void)ntpshm_put(session,session->gpsdata.sentence_time+0.075); +#endif mask |= TIME_SET; } Wayne Knowles wrote: > Tim, Chris, > > Over a month ago I experimented with getting GPSD and the Tunderbolt working > together. > I quickly added support for the missing TSIP packet types, and was able to get > xgps to display lat, long, time and constellation status. I did manage to > get NTP to work, have not invested the time into getting the 1PPS signal > working under FreeBSD yet. > > I have attached my patches against the gpsd source repository. Note that I > did not invest much time understanding the internals of gpsd beforehand so > some aspects may not be fully implemented. > > -- > Wayne ZL2BKC > > > On Fri, Jun 13, 2008 at 8:58 AM, Christian Vogel wrote: >> gpsd: GPS Time 485697.250000 1483 14.000000 > that's encouraging > >> gpsd: Sat info: mode 1, satellites used 5: 18 9 28 15 26 > As is this. > >> gpsd: Unhandled TSIP superpacket type 0xab > > "thar's yer problem"... kinda. > > yes, we don't handle 0xAB, but that's just timing information. I see > no indication that the receiver is outputting position reports. I > should have this sorted a few hours after my Thunderbolt arrives. > Guess I need to prod the receiver into telling me where it thinks it > is. > >> Unfortunately, it does not show any information about time or position on >> a connected cgps/xgps client. >> >> Chris >> >> _______________________________________________ >> time-nuts mailing list -- 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 chris.kuethe at gmail.com Sun Aug 10 16:53:59 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Sun, 10 Aug 2008 13:53:59 -0700 Subject: [time-nuts] thunderbolt for ntpd or gpsd In-Reply-To: <489F529A.1030700@intt.net> References: <200806151159.45824.w.knowles@xtra.co.nz> <489F529A.1030700@intt.net> Message-ID: <91981b3e0808101353n2b6706acq61f341b2c8e23de8@mail.gmail.com> On Sun, Aug 10, 2008 at 1:42 PM, Scott Mace wrote: > ntpshm_put() needs to be called in the 0xab case as well for ntp to work. done. > --- gpsd/trunk/tsip.c 2008-08-08 23:38:27.000000000 -0500 > +++ ../gpsd/trunk/tsip.c 2008-08-09 04:14:09.000000000 -0500 > @@ -65,7 +65,7 @@ > /* XXX clever heuristic to decide if the parity change is required. > */ > session->driver.tsip.parity = session->gpsdata.parity; > session->driver.tsip.stopbits = session->gpsdata.stopbits; > - gpsd_set_speed(session, session->gpsdata.baudrate, 'O', 1); > + gpsd_set_speed(session, session->gpsdata.baudrate, 'N', 1); > break; > > case 1: not committing this - i'd prefer a heuristic to autodetect the parity. i'm open to suggestions on how to do that. > @@ -674,6 +674,10 @@ > > session->gpsdata.fix.time = session->gpsdata.sentence_time = > gpstime_to_unix((int)s1, f1) - (double)u1; > +#ifdef NTPSHM_ENABLE > + if (session->context->enable_ntpshm) > + > (void)ntpshm_put(session,session->gpsdata.sentence_time+0.075); > +#endif > mask |= TIME_SET; > } just committed this part... From lists at philpem.me.uk Sun Aug 10 17:45:13 2008 From: lists at philpem.me.uk (Philip Pemberton) Date: Sun, 10 Aug 2008 22:45:13 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO Message-ID: <489F6169.30301@philpem.me.uk> Hi folks, I've been following the mailing list for a few weeks using Pipermail (the web-based archive) and I figured now was a good time to jump in (so to speak). I'm working on a GPS-disciplined oscillator, based on a Trimble SVeeSix GPS receiver, and a homebrew OCXO. I've got a pair of 10MHz 50-degree-C oven crystals, and have a pretty good idea how to handle the temperature regulation. What I'm planning to do is mount the crystal on a copper plate with two power transistors, using heatsink compound between the copper and transistors/crystal case, and fit a temperature sensor to the top side of the crystal case. I'm planning to use a copper bracket to hold the sensor onto the crystal, and in turn mount the crystal to the copper base. As far as temperature regulation goes, I'm going to use a PIC microcontroller (one of the 8-pin chips with an A/D converter) to monitor the temperature of the crystal, and use a PID loop to control the two power transistors to maintain a temperature of 50C +/- 2 Celsius (the accuracy spec of the temperature sensor). I also have other higher-accuracy sensors (Dallas DS18S20 and DS18B20) that I can calibrate with; these are accurate to around half a degree Celsius with a resolution of 0.5C. The whole thing is going to be mounted in a metal box lined with 1/2in thick polystyrene, with all external connections made via Molex KK connectors and standard hookup wire. If there's any advantage to doing so, I might use RG174 cable for the oscillator output, but otherwise I'll stick to the KKs and maybe twist the OUT/GND wires together. What I'm stuck on is the oscillator itself. The crystals are standard parallel-resonant parts, with a load capacitance of 30 picofarads. I've got a few varicap diodes (varactors) that I'm planning to use to allow external trimming of the frequency, on top of what the ~20pf "coarse" preset will allow. So on one side of the crystal I'll have a 33pf capacitor, and on the other a 20pf load capacitor, the varicap and a low-value DC-blocking capacitor for said varicap. The standard oscillator circuit for TTL seems to be a pair of 74HC04 inverters and a few passives, or a transistor version that outputs a sine-wave. Are there any particular types of oscillator that are more suitable for high-accuracy timing? What I'd like to do is use this oscillator to calibrate frequency counters and check the calibration on oscilloscopes and similar. Being able to lock function generators (a mix of custom DDS sine generators based on Analog Devices DDS chips and FPGA-based complex-signal DDSes) against the oscillator would be very useful as well. Should I be going for a 1V sine output and then convert this to TTL in the generators (which are easy to retrofit with adapter boards) or output TTL from the reference and leave it at that? What design parameters should I be optimising for, and how? Given that a standard crystal is good to roughly 100ppm, and most commercial OCXOs are specified to be within 1x10^-9 or better, I'm aiming for around 1ppm to start with. Is even this realistic for a homebrew device? There seems to be quite a bit of difference between just building a 4MHz oscillator to run a PIC MCU to building an accurate frequency reference source... As far as parts are concerned, I'm planning to use either a BB153 or BB148 varicap, a Microchip TC1047AVNBTR temperature sensor, a National Semiconductor LM4040CIM3-4.1 voltage reference for the PIC's A/D, two BD139 power transistors and a PIC12F683 microcontroller. Thanks, -- Phil. lists at philpem.me.uk http://www.philpem.me.uk/ From bruce.griffiths at xtra.co.nz Sun Aug 10 19:35:15 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Mon, 11 Aug 2008 11:35:15 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F6169.30301@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> Message-ID: <489F7B33.9010009@xtra.co.nz> Philip Pemberton wrote: > Hi folks, > I've been following the mailing list for a few weeks using Pipermail (the > web-based archive) and I figured now was a good time to jump in (so to speak). > > I'm working on a GPS-disciplined oscillator, based on a Trimble SVeeSix GPS > receiver, and a homebrew OCXO. I've got a pair of 10MHz 50-degree-C oven > crystals, and have a pretty good idea how to handle the temperature regulation. > > What I'm planning to do is mount the crystal on a copper plate with two > power transistors, using heatsink compound between the copper and > transistors/crystal case, and fit a temperature sensor to the top side of the > crystal case. I'm planning to use a copper bracket to hold the sensor onto the > crystal, and in turn mount the crystal to the copper base. > > As far as temperature regulation goes, I'm going to use a PIC > microcontroller (one of the 8-pin chips with an A/D converter) to monitor the > temperature of the crystal, and use a PID loop to control the two power > transistors to maintain a temperature of 50C +/- 2 Celsius (the accuracy spec > of the temperature sensor). I also have other higher-accuracy sensors (Dallas > DS18S20 and DS18B20) that I can calibrate with; these are accurate to around > half a degree Celsius with a resolution of 0.5C. > > The whole thing is going to be mounted in a metal box lined with 1/2in > thick polystyrene, with all external connections made via Molex KK connectors > and standard hookup wire. If there's any advantage to doing so, I might use > RG174 cable for the oscillator output, but otherwise I'll stick to the KKs and > maybe twist the OUT/GND wires together. > > What I'm stuck on is the oscillator itself. The crystals are standard > parallel-resonant parts, with a load capacitance of 30 picofarads. I've got a > few varicap diodes (varactors) that I'm planning to use to allow external > trimming of the frequency, on top of what the ~20pf "coarse" preset will > allow. So on one side of the crystal I'll have a 33pf capacitor, and on the > other a 20pf load capacitor, the varicap and a low-value DC-blocking capacitor > for said varicap. > > The standard oscillator circuit for TTL seems to be a pair of 74HC04 > inverters and a few passives, or a transistor version that outputs a > sine-wave. Are there any particular types of oscillator that are more suitable > for high-accuracy timing? > > What I'd like to do is use this oscillator to calibrate frequency counters > and check the calibration on oscilloscopes and similar. Being able to lock > function generators (a mix of custom DDS sine generators based on Analog > Devices DDS chips and FPGA-based complex-signal DDSes) against the oscillator > would be very useful as well. Should I be going for a 1V sine output and then > convert this to TTL in the generators (which are easy to retrofit with adapter > boards) or output TTL from the reference and leave it at that? > > What design parameters should I be optimising for, and how? > > Given that a standard crystal is good to roughly 100ppm, and most > commercial OCXOs are specified to be within 1x10^-9 or better, I'm aiming for > around 1ppm to start with. Is even this realistic for a homebrew device? > > There seems to be quite a bit of difference between just building a 4MHz > oscillator to run a PIC MCU to building an accurate frequency reference source... > > As far as parts are concerned, I'm planning to use either a BB153 or BB148 > varicap, a Microchip TC1047AVNBTR temperature sensor, a National Semiconductor > LM4040CIM3-4.1 voltage reference for the PIC's A/D, two BD139 power > transistors and a PIC12F683 microcontroller. > > Thanks, > Philip If you are serious forget the fancy digital or semiconductor temperature sensors they aren't good enough. However with your crude oven structure using higher performance sensors may perhaps be unwarranted. For the best performance, unless you use a bridge oscillator circuit of some type, you will need to control the temperature of all the oscillator components as well. Its best to bond the sensor into a well drilled in the oven using non electrically conductive thermal epoxy. An analog bridge using an RTD or an NTC thermistor can have much better stability. If you use an appropriate high resolution sigma delta ADC it can reverse the bridge excitation polarity as part of the measurement sequence and give you most of the benefits of an AC bridge with fewer devices and lower cost. The next step up from the gate oscillator for fundamental crystals is perhaps Wenzel's circuit: http://www.wenzel.com/pdffiles1/pdfs/xtalosc.pdf This circuit needs a little optimisation to improve its performance. A higher base collector voltage on the oscillator transistor is desirable. This can be done using a pnp transistor to sense the oscillator transistor dc collector current and regulate it by adjusting the dc base current. Replacing the Source follower buffer with a common base transistor (allow the crystal current to flow into the emitter rather than Wenzel's shunt C) will provide higher reverse isolation. Cascade a few transformer coupled CB stages to provide gain and increased isolation. With a reverse terminated transformer coupled load in the collector of the output CB stage any load from open to short circuit can be driven without adverse effects. The inductor shown in Wenzel's circuit wont be required with your crystal either with or without a CB output stage. The limiting action occurs by cutting off the oscillator transistor during part of the cycle. The dc collector current of the oscillator transistor sets the crystal current. I would build a room temperature version first for debugging. To minimise the phase noise contributed by the varicap the EFC range should be as small as is practical. A very low noise power supply is also required for good performance. A modified version (uses 2 transistors and larger capacitors) of Wenzels active supply filter can be used to reduce the power supply noise by 30-40dB for frequencies above 1Hz or so. http://www.wenzel.com/documents/finesse.html I can provide circuit schematics if you are interested. Bruce From bruce.griffiths at xtra.co.nz Sun Aug 10 20:51:18 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Mon, 11 Aug 2008 12:51:18 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F6169.30301@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> Message-ID: <489F8D06.2020604@xtra.co.nz> Philip When using a crystal in an oven you should use a crystal specified for oven operation at a specific temperature. The crystal frequency should be specified for the desired oven temperature. For example for an AT cut crystal the crystal frequency can be approximated by as a cubic function of temperature. There are usually a couple of stationary points on the curve where the slope of frequency versus temperature is zero. The crystal should be cut so that one of these points coincides with the oven temperature as this minimises the effect of small errors in the oven temperature set point on the frequency stability. A crystal specified for non oven operation is usually cut to minimise the frequency variation over the specified range of operating temperaures. The frequency of such a crystal at one of the turning points may be several tens of ppm away from the nominal frequency. The upper turning point may not even be suitable as it may be too high or even within the expected ambient temperature range. It is also possible to cut the crystal so that the stationary points coincide at a point of inflection. In this case the frequency change corresponding to small deviations from this temperature are much smaller than those at the turning points of a conventional oven crystal. However this inflection point will lie close to room temperature for an AT cut crystal so that the "oven" will have to be cooled when the ambient temperature is above this point and heated when it is below this point. Bruce From wb6bnq at cox.net Sun Aug 10 23:26:48 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Sun, 10 Aug 2008 20:26:48 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO References: <489F6169.30301@philpem.me.uk> Message-ID: <489FB178.78A9653A@cox.net> Hello Philip, I agree with Bruce about the digital stuff and semiconductor temperature sensors, etc. From your commentary I think you should do some reading before proceeding. Here are some suggestions; The first is a series of Application notes from Agilent (old hp test div) called AN-200. A total of 5 App notes comprise the AN-200 series. If you go to the following Web page and enter AN-200 at the top of the page in the search box, you will get a return of all the AN-200 booklets in PDF that can be downloaded. The BIG one is AN-200-2, but it would be to your advantage to collect all of them. You need to paste in the entire link below if your browser doesnt see the whole thing when clicking on it. [1]http://www.home.agilent.com/agilent/facet.jspx?t=80030.k.1&cc=US&lc= eng&sm=g&pageMode=TM Next is the AN-52 series, also at the above site. The original, produced in the 1960's is AN-52. Later, in the 1970's, they rewrote and split this App note into two titled AN-52-1 & AN-52-2. There is also AN-52-4, but that does not cover your interests at the moment. I would suggest downloading ALL of them, including the original AN-52. An-52 does have historical perspective and a few things not included in the later rewrites. That should keep you busy for a while. A lot of stuff on the WEB, some good and some not so good, just take it with a grain of salt ! NIST (the old NBS) has several things worth reading, however, most of that deals with the measurement process or is a rigorous mathematical analysis of one thing or another. In my experience, an inexpensive metal can crystal and a decent oscillator circuit will hang in there under 10ppm in a regular room with a stable ambient temperature. HP used such a crystal in their 60KHz receiver because it was controlled in a loop from the 60KHz, thus approaching the accuracy and stability of the transmitted signal. Second it does not take much to get parts in 10^-7 range. Temperature compensated crystal oscillators easily handle that level. With care, a crystal oscillator in a well designed circuit can reach parts in 10^-8 with a bit-bang oven control. HP did that in the late 1950's. From that point the difficulty is logarithmic. Bill....WB6BNQ Philip Pemberton wrote: Hi folks, I've been following the mailing list for a few weeks using Pipermail (the web-based archive) and I figured now was a good time to jump in (so to speak). I'm working on a GPS-disciplined oscillator, based on a Trimble SVeeSix GPS receiver, and a homebrew OCXO. I've got a pair of 10MHz 50-degree-C oven crystals, and have a pretty good idea how to handle the temperature regulation. What I'm planning to do is mount the crystal on a copper plate with two power transistors, using heatsink compound between the copper and transistors/crystal case, and fit a temperature sensor to the top side of the crystal case. I'm planning to use a copper bracket to hold the sensor onto the crystal, and in turn mount the crystal to the copper base. As far as temperature regulation goes, I'm going to use a PIC microcontroller (one of the 8-pin chips with an A/D converter) to monitor the temperature of the crystal, and use a PID loop to control the two power transistors to maintain a temperature of 50C +/- 2 Celsius (the accuracy spec of the temperature sensor). I also have other higher-accuracy sensors (Dallas DS18S20 and DS18B20) that I can calibrate with; these are accurate to around half a degree Celsius with a resolution of 0.5C. The whole thing is going to be mounted in a metal box lined with 1/2in thick polystyrene, with all external connections made via Molex KK connectors and standard hookup wire. If there's any advantage to doing so, I might use RG174 cable for the oscillator output, but otherwise I'll stick to the KKs and maybe twist the OUT/GND wires together. What I'm stuck on is the oscillator itself. The crystals are standard parallel-resonant parts, with a load capacitance of 30 picofarads. I've got a few varicap diodes (varactors) that I'm planning to use to allow external trimming of the frequency, on top of what the ~20pf "coarse" preset will allow. So on one side of the crystal I'll have a 33pf capacitor, and on the other a 20pf load capacitor, the varicap and a low-value DC-blocking capacitor for said varicap. The standard oscillator circuit for TTL seems to be a pair of 74HC04 inverters and a few passives, or a transistor version that outputs a sine-wave. Are there any particular types of oscillator that are more suitable for high-accuracy timing? What I'd like to do is use this oscillator to calibrate frequency counters and check the calibration on oscilloscopes and similar. Being able to lock function generators (a mix of custom DDS sine generators based on Analog Devices DDS chips and FPGA-based complex-signal DDSes) against the oscillator would be very useful as well. Should I be going for a 1V sine output and then convert this to TTL in the generators (which are easy to retrofit with adapter boards) or output TTL from the reference and leave it at that? What design parameters should I be optimising for, and how? Given that a standard crystal is good to roughly 100ppm, and most commercial OCXOs are specified to be within 1x10^-9 or better, I'm aiming for around 1ppm to start with. Is even this realistic for a homebrew device? There seems to be quite a bit of difference between just building a 4MHz oscillator to run a PIC MCU to building an accurate frequency reference source... As far as parts are concerned, I'm planning to use either a BB153 or BB148 varicap, a Microchip TC1047AVNBTR temperature sensor, a National Semiconductor LM4040CIM3-4.1 voltage reference for the PIC's A/D, two BD139 power transistors and a PIC12F683 microcontroller. Thanks, -- Phil. lists at philpem.me.uk [2]http://www.philpem.me.uk/ _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [3]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.home.agilent.com/agilent/facet.jspx?t=80030.k.1&cc=US&lc=eng&sm=g&pageMode=TM 2. http://www.philpem.me.uk/ 3. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From david at endor.com Mon Aug 11 00:12:35 2008 From: david at endor.com (David McGaw) Date: Mon, 11 Aug 2008 00:12:35 -0400 Subject: [time-nuts] GPS shielding by power lines? In-Reply-To: <001601c8fa65$1fc4ef20$0900a8c0@AM> References: <001601c8fa65$1fc4ef20$0900a8c0@AM> Message-ID: <200808110414.m7B4EAIX008124@mailhub2.dartmouth.edu> You didn't say if you tried the antenna under the power lines but outside the cabin. What is translucent to light may not be to microwaves. David N1HAC At 05:15 PM 8/9/2008, you wrote: >Hi all, in the process of setting up a GPS time standard for a Radio >Astronomy facility (amateur) we installed a GPS receiver in a small cabin >with a translucent roof, thinking that would not impede the GPS signal. >After a lot of head scratching as to why we were not getting the performane >we got at another site, we realised that the "convenient position" for the >cabin was directly below a three phase 11kV power distribution line ( common >UK rural electricity distribution system). We extended the cable and moved >the antenna about 20 - 30 feet to the side of the line run, which was >mounted on wooden poles at about 25 feet. In this position we immediately >got a reliable fix. The fix and number of usable satellites degrades as we >move nearer the lines. > >The thought was that there as interference arcing or corona noise from the >line insulators, and a receiver (AM) was deployed to listen for what was >expected to be a substantial wide band noise signal....we didnt hear one! We >are now confused about what the effect is. The signal could not be >"screened" by the wires which are about 3 feet apart, but they definite >provide a cone of interference directly under the run. The experiment was >later repeated with two further different GPS receivers and produced the >same result. > >Has anyone seen this before? have you any idea of what level noise we should >be looking for? I believe this is a wide signal so maybe an AM receiver is >not the best choice The area is a rural, horticultural area (called market >garden in the UK) We are obviouslt concerned to trace any noise sources in >the vicinity of the Hydrogen line frequency at 1420MHz. > >Alan G3NYK > > >_______________________________________________ >time-nuts mailing list -- 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 bill at iaxs.net Mon Aug 11 03:11:08 2008 From: bill at iaxs.net (Bill Hawkins) Date: Mon, 11 Aug 2008 02:11:08 -0500 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F6169.30301@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> Message-ID: <001801c8fb81$6da3e670$021ba8c0@cyrus> Phil, Good on ya. When I have the time, I'll try going back to first principles. I've spent 40 years working with PID controllers and their sensors and actuators. Rule of thumb: If the transport delay (dead time between changing the heater and sensing the change) is 10% of the system time constant, you have to reduce the PID gain by about half to maintain stability (of the phase margin in a feedback loop). In your case, do NOT mount the sensor on the crystal. Mount it halfway between your heaters and expect the copper plate to come to a steady-state temperature inside the insulated cavity. Do not mount it with any form of insulating adhesive which will increase the delay. Maybe hold it down with a copper strip, like the crystal. As Bruce Griffiths suggests, use an analog sensor and a resistance bridge. Then the null signal can be digitized with low accuracy requirements, compared to digitizing the temperature to 10E-9. Mount the analog stuff in the controlled enclosure. Use fixed resistors to balance the bridge at 50C so there are no adjustments in the oven. Plan on putting the oscillator in there, too. Never mind being dead on 50C because where you want to be is on a flat spot on the temperature curve, so maybe you don't have to hold 10E-9. Your digital PID is looking at the digitized bridge error as its measurement. A setpoint can vary that error to find the flat spot. Don't forget that components and solder joints age at 50C, so plan on making adjustments once a week until the frequency stabilizes. The accuracy of the sensor is not important. What you want is precision and stability. You want the highest gain you can get in the PID, which means doing the stuff for delay as well as determining the time constant of your oven at 50C so you can set the integral term. Bill Hawkins -----Original Message----- From: Philip Pemberton Sent: Sunday, August 10, 2008 4:45 PM What I'm planning to do is mount the crystal on a copper plate with two power transistors, using heatsink compound between the copper and transistors/crystal case, and fit a temperature sensor to the top side of the crystal case. I'm planning to use a copper bracket to hold the sensor onto the crystal, and in turn mount the crystal to the copper base. As far as temperature regulation goes, I'm going to use a PIC microcontroller (one of the 8-pin chips with an A/D converter) to monitor the temperature of the crystal, and use a PID loop to control the two power transistors to maintain a temperature of 50C +/- 2 Celsius (the accuracy spec of the temperature sensor). I also have other higher-accuracy sensors (Dallas DS18S20 and DS18B20) that I can calibrate with; these are accurate to around half a degree Celsius with a resolution of 0.5C. From alan.melia at btinternet.com Mon Aug 11 06:00:03 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Mon, 11 Aug 2008 11:00:03 +0100 Subject: [time-nuts] GPS shielding by power lines? References: <001601c8fa65$1fc4ef20$0900a8c0@AM> <200808110414.m7B4EAIX008124@mailhub2.dartmouth.edu> Message-ID: <004b01c8fb99$6b635860$0900a8c0@AM> Hi David yes indeed and the qualify of the fix imporves as we move away at right angles to the line....despite some trees and a tall hedge on one side. Dramatic and quite repeatable. Alan G3NYK ----- Original Message ----- From: "David McGaw" To: "Discussion of precise time and frequency measurement" Sent: Monday, August 11, 2008 5:12 AM Subject: Re: [time-nuts] GPS shielding by power lines? > You didn't say if you tried the antenna under the power lines but > outside the cabin. What is translucent to light may not be to microwaves. > > David N1HAC . From lists at philpem.me.uk Mon Aug 11 07:35:16 2008 From: lists at philpem.me.uk (Philip Pemberton) Date: Mon, 11 Aug 2008 12:35:16 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F7B33.9010009@xtra.co.nz> References: <489F6169.30301@philpem.me.uk> <489F7B33.9010009@xtra.co.nz> Message-ID: <48A023F4.10807@philpem.me.uk> Bruce Griffiths wrote: > If you are serious forget the fancy digital or semiconductor > temperature sensors they aren't good enough. I was intending to use the slow Dallas chips as a calibration reference (out-of-box they're usually quite accurate) and for testing. Is there any particular reason the analog-output (Microchip TC1047A) sensors are no good? > For the best performance, unless you use a bridge oscillator circuit > of some type, you will need to control the temperature of all the > oscillator components as well. I did have a "plan B" -- a hollow metal box with a metal sheet soldered inside at the half-way point. The crystal and oscillator circuitry would be mounted in the bottom half, and the temperature control in the top half. The temperature sensor is a three-pin SOT23 (about the size of a grain of rice) and the ground is a single pin on one side. I was thinking about mounting the sensor directly on the copper, using a small piece of Kapton tape to stop the sensor's Vout or Vcc shorting against the grounded copper sheet. That would leave two hollow air-filled cavities for the control circuitry and hold the temperature of that reasonably close to that of that of the crystal (minus a few degrees). > An analog bridge using an RTD or an NTC thermistor can have much > better stability. That sounds about right.. I was going to use a Pt100 or Pt1000 RTD, but couldn't find any decent information on them other than the resistance being 100R or 1kR at 25C -- even the manufacturer's datasheets were somewhat thin on information. > If you use an appropriate high resolution sigma delta ADC it can > reverse the bridge excitation polarity as part of the measurement > sequence and give you most of the benefits of an AC bridge with fewer > devices and lower cost. IIRC the A/D on the PIC is a 10-bit successive-approximation type with a built-in sample-and-hold (though other types have 12-bit converters). That's a measurement range of 1024 counts, which with the 4.096V reference provides a resolution of 4mV, or 1/2.5 of a degree C per count. 4V is actually the minimum reference voltage the A/D can accept. Sensor output is ((degrees_c * 10) + 500) mV. > I would build a room temperature version first for debugging. I'm planning to do that anyway. I've got a few 10MHz room-temp crystals of a similar spec to the oven crystals that I can use, and I can probably use the same parts in the prototype oven for testing. > To minimise the phase noise contributed by the varicap the EFC range > should be as small as is practical. That's the part that's going to need "a bit" of experimentation I think :) > A very low noise power supply is also required for good performance. > A modified version (uses 2 transistors and larger capacitors) of > Wenzels active supply filter can be used to reduce the power supply > noise by 30-40dB for frequencies above 1Hz or so. > http://www.wenzel.com/documents/finesse.html > > I can provide circuit schematics if you are interested. That would be great, if it's not too much trouble. Thanks, Phil. From lists at philpem.me.uk Mon Aug 11 07:38:50 2008 From: lists at philpem.me.uk (Philip Pemberton) Date: Mon, 11 Aug 2008 12:38:50 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F8D06.2020604@xtra.co.nz> References: <489F6169.30301@philpem.me.uk> <489F8D06.2020604@xtra.co.nz> Message-ID: <48A024CA.9090001@philpem.me.uk> Bruce Griffiths wrote: > When using a crystal in an oven you should use a crystal specified for > oven operation at a specific temperature. Which is what my crystal is -- a 10MHz oven crystal, specified for a 30pF load capacitance and operation at 50 degrees Celsius. I'm intending to use the oscillator at an ambient temperature of up to 35 Celsius (if it's warmer than that, then I'll likely have other things to worry about!). That's on the border of what the Agilent appnotes suggest as reasonable (15 to 20 Celsius), but still within range. In real terms, it's probably not going to see an ambient temperature higher than 25C. Well, not in this country anyway. Thanks, Phil. From bruce.griffiths at xtra.co.nz Mon Aug 11 10:09:46 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Tue, 12 Aug 2008 02:09:46 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A023F4.10807@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> <489F7B33.9010009@xtra.co.nz> <48A023F4.10807@philpem.me.uk> Message-ID: <48A0482A.40508@xtra.co.nz> Philip Pemberton wrote: > Bruce Griffiths wrote: > > If you are serious forget the fancy digital or semiconductor > > temperature sensors they aren't good enough. > > I was intending to use the slow Dallas chips as a calibration reference > (out-of-box they're usually quite accurate) and for testing. Is there > any particular reason the analog-output (Microchip TC1047A) sensors are > no good? > > You need millidegree sensistivity and stability, no sensor of this type has the required stability. Only good thermistors and RTDs approach this. > > For the best performance, unless you use a bridge oscillator circuit > > of some type, you will need to control the temperature of all the > > oscillator components as well. > > I did have a "plan B" -- a hollow metal box with a metal sheet soldered > inside at the half-way point. The crystal and oscillator circuitry would > be mounted in the bottom half, and the temperature control in the top > half. The temperature sensor is a three-pin SOT23 (about the size of a > grain of rice) and the ground is a single pin on one side. I was > thinking about mounting the sensor directly on the copper, using a small > piece of Kapton tape to stop the sensor's Vout or Vcc shorting against > the grounded copper sheet. > > That would leave two hollow air-filled cavities for the control > circuitry and hold the temperature of that reasonably close to that of > that of the crystal (minus a few degrees). > > The tempco contribution of oscillator components is such that there temperature should be stable to far better than a few degrees. Thermal gradients within the oven need to be minimised. > > An analog bridge using an RTD or an NTC thermistor can have much > > better stability. > > That sounds about right.. I was going to use a Pt100 or Pt1000 RTD, but > couldn't find any decent information on them other than the resistance > being 100R or 1kR at 25C -- even the manufacturer's datasheets were > somewhat thin on information. > > These sensors like most platinum resistance thermometers elements have a tempco of about 3900 ppm/K or so. Copper resistors have also be used for this purpose and have a similar tempco. Thermistors are much more sensitive to temperature and high quality ones are almost as stable. The output from a bridge using RTDs is relatively low and precautions have to be taken to eliminate thermocouple effects as well as amplifier offsets. An AC bridge excitation technique or periodically reversing the bridge excitation polarity can help. > > If you use an appropriate high resolution sigma delta ADC it can > > reverse the bridge excitation polarity as part of the measurement > > sequence and give you most of the benefits of an AC bridge with fewer > > devices and lower cost. > > IIRC the A/D on the PIC is a 10-bit successive-approximation type with a > built-in sample-and-hold (though other types have 12-bit converters). > > That's a measurement range of 1024 counts, which with the 4.096V > reference provides a resolution of 4mV, or 1/2.5 of a degree C per > count. 4V is actually the minimum reference voltage the A/D can accept. > > Insufficient resolution you need a least count below 0.001C. If you use that ADC it will need a suitable preamp. However a linear range of a little less than 1C is sufficient. A high resolution sigma delta ADC is probably a better choice as a low drift preamp isnt required. The output DAC (of whatever type) needs to be monotonic and have high resolution (18 bits or more) to allow the temperature to be controlled to better than 0.001C. There are several techniques for achieving more resolution from a low resolution DAC. > Sensor output is ((degrees_c * 10) + 500) mV. > > > I would build a room temperature version first for debugging. > > I'm planning to do that anyway. I've got a few 10MHz room-temp crystals > of a similar spec to the oven crystals that I can use, and I can > probably use the same parts in the prototype oven for testing. > > > To minimise the phase noise contributed by the varicap the EFC range > > should be as small as is practical. > > That's the part that's going to need "a bit" of experimentation I think :) > > If you use a manual trimmer as well then a range of 1E-7 or so is usually sufficient. If all frequency adjustment is via EFC then you need to accommodate at least 10 years worth of aging. > > A very low noise power supply is also required for good performance. > > A modified version (uses 2 transistors and larger capacitors) of > > Wenzels active supply filter can be used to reduce the power supply > > noise by 30-40dB for frequencies above 1Hz or so. > > http://www.wenzel.com/documents/finesse.html > > > > I can provide circuit schematics if you are interested. > > That would be great, if it's not too much trouble. > > Thanks, > Phil. > What are the crystal parameters: Q? ESR? L? Cshunt? Cseries? What crystal cut is used AT?, BT?, SC? Is it a fundamental crystal? Will post the modified P/S filter in a few hours together with the modified Wenzel low noise oscillator circuit. If you are using an overtone crystal or an SC crystal then provisions need to be made to suppress unwanted modes. In this case a somewhat different oscillator configuration is perhaps advisable. Something like one of the Driscoll type oscillators which have a tuned tank for mode suppression can be used. Otherwise a somewhat more complex oscillator with AGC may be necessary. Bruce From holrum at hotmail.com Mon Aug 11 12:56:43 2008 From: holrum at hotmail.com (Mark Sims) Date: Mon, 11 Aug 2008 16:56:43 +0000 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: For your temperature sensor and/or ADC consider the Analog Devices AD537 voltage to frequency converter chip. It has an onboard temperature sensor or could be interfaced to a thermistor, etc. The on chip sensor has a fairly large thermal mass. If you need instantaneous response to temperature use a very small thermistor. Since the output is frequency, any time nut worth his/her/its salt should be able to come up with a suitable counter circuit. One system that I did had the V/F freq set around 200 Hz. Counting a 16 MHz clock over 256 cycles of V/F waveform yielded microdegree resolution. ---------------------------------------- _________________________________________________________________ Get more from your digital life. Find out how. http://www.windowslive.com/default.html?ocid=TXT_TAGLM_WL_Home2_082008 From david.partridge at dsl.pipex.com Mon Aug 11 13:42:59 2008 From: david.partridge at dsl.pipex.com (David C. Partridge) Date: Mon, 11 Aug 2008 18:42:59 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F6169.30301@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> Message-ID: <93BED0F385694691BE930F8A55EAB705@APOLLO> Stupid question - why build your own OCXO when you can buy a pretty good Oscilloquartz OCXO from eBay item number 300247357254 for almost a song? Yes I know - it's fun! Dave From lists at philpem.me.uk Mon Aug 11 16:25:29 2008 From: lists at philpem.me.uk (Philip Pemberton) Date: Mon, 11 Aug 2008 21:25:29 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <93BED0F385694691BE930F8A55EAB705@APOLLO> References: <489F6169.30301@philpem.me.uk> <93BED0F385694691BE930F8A55EAB705@APOLLO> Message-ID: <48A0A039.8080503@philpem.me.uk> David C. Partridge wrote: > Stupid question - why build your own OCXO when you can buy a pretty good > Oscilloquartz OCXO from eBay item number 300247357254 for almost a song? I can think of a couple of reasons: 1) If it breaks, I can rip it open, poke and probe it, figure out what's wrong and then hopefully fix it. I've got loads of T&M gear that sadly never sees the use it should -- a very nice Tek TDS2024B DSO that's been used maybe a dozen times, a HP 1651B logic analyser that's been used about as much (but bought second-hand with severe screen burn), the list goes on. 2) It's nice to know how things work - I have a severe case of blackboxophobia. I hate little black boxes that do magic things, and have zero parts availability. This has gotten to the point where I've built a model logic analyser to learn how they work, and most of my complex signal generators are homebrew too. I've got a nice DDS signal generator that I'm working on at the moment, which should by virtue of the ADI DDS chip be able to do AM, FM, BPSK, QPSK, (maybe) 8PSK and a few other modulation modes. I'm building it for... testing a Radio 4 timecode receiver. Bonus points if I can make it produce DVB-S compliant streams at 70MHz IF and upconvert to 1.x GHz L-band to test satellite receivers. That's quite far down on the projects list though :) 3) I try and avoid ebay where possible. I've had pretty good luck with UK and US sellers, but the few I've dealt with from other countries have been horrendous, especially those in the vicinity of China and Hong Kong. Six months for one parcel to arrive... Anyone here listen to the "SolderSmoke" podcast? #72 pretty much sums it up. I like to know what things do, and I can't stand to buy something if I can build it from parts I've got in my junk box. In my weird world, if I've already bought the parts, then effectively my cost is zero.. I've got the bits, I might as well use them. Plus I was actually looking at new OCXOs -- at the time I decided to do this, there weren't any on eBay. The lowest quote I got was ?132 +VAT (rounded up from the quote I just dug out...) for a 12V, fairly low-tech OCXO. The shiny new high-tech one with the TTL status output and other stuff was about ?240 and some change. In effect, it's cost me ?37 for the crystals, and ~?10 for a dozen each of the temperature sensors and voltage references. I'm still below half the cost of a brand-new commercial OCXO. > Yes I know - it's fun! And it's fun. That too. :) Thanks, -- Phil. lists at philpem.me.uk http://www.philpem.me.uk/ From lists at philpem.me.uk Mon Aug 11 16:28:28 2008 From: lists at philpem.me.uk (Philip Pemberton) Date: Mon, 11 Aug 2008 21:28:28 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489FB178.78A9653A@cox.net> References: <489F6169.30301@philpem.me.uk> <489FB178.78A9653A@cox.net> Message-ID: <48A0A0EC.8080003@philpem.me.uk> WB6BNQ wrote: > The first is a series of Application notes from Agilent (old hp test > div) called AN-200. A total of 5 App notes comprise the AN-200 series. > If you go to the following Web page and enter AN-200 at the top of the > page in the search box, you will get a return of all the AN-200 booklets > in PDF that can be downloaded. The BIG one is AN-200-2, but it would be > to your advantage to collect all of them. You need to paste in the > entire link below if your browser doesn't see the whole thing when > clicking on it. Hm, nothing found on Agilent's site, but Google found it (search term: "agilent.com AN-200"). Lots of interesting stuff there, from quartz oscillator basics through microwave signal generation and measurement... > That should keep you busy for a while. A lot of stuff on the WEB, some > good and some not so good, just take it with a grain of salt ! NIST > (the old NBS) has several things worth reading, however, most of that > deals with the measurement process or is a rigorous mathematical > analysis of one thing or another. Well I was looking at the manual for the ELV OCXO400 (http://www.elv-downloads.de/service/manuals/OCXO400/OCXO400_KM_G_010502.pdf) as a partial reference, and the disassembly photos for one of the HP dual-oven oscillators (can't find the link at the moment). I dismissed the ELV's mechanical design based on the fact that it was two BC337 (read: low power) transistors mounted on each side of the crystal, with a cheap thermistor on top. No real thermal load at all -- as soon as the transistors turn on, the temperature is likely to shoot WAY, WAY up, then drop FAST when the transistors are turned off. The comparator-based thermostat-type temperature control isn't likely to make that much easier either. Apparently the oscillator circuit is quite badly designed too (based on information at http://glowbug.nl/projects/M51.html). Badly biased output transistors and mismatched xtal load capacitance mainly. > Second it does not take much to get parts in 10^-7 range. Temperature > compensated crystal oscillators easily handle that level. With care, a > crystal oscillator in a well designed circuit can reach parts in 10^-8 > with a bit-bang oven control. HP did that in the late 1950's. From > that point the difficulty is logarithmic. It certainly seems that way... Nice to know it's not quite as hard as it looks. The ELV is specced at 2x10^-8 stability and uses an AT-cut HC49U fundamental-mode parallel-resonant crystal. I don't have the specs for the crystal cut used for my 10MHz xtals, but I do know the base specifications are almost identical to the ELV unit's crystal. I should probably mention the main reason I wanted to use the PIC control -- so I can adjust the oven parameters (desired temperature, PID variables, and so on) in real time, and read off the oven status at the same time (current temperature, target temperature, last warmup time, hours run since last power cycle, total crystal age, starting temperature, crystal oscillator state, and so on). Obviously the turning point for each crystal isn't going to be exactly 50.0000000... Celsius, so being able to hook up a high-resolution counter and figure out what the exact turning point is and program the thermal management kit with that would be useful. In truth this is more a research and learning exercise. It'd just be nice to end up with something that compares reasonably well to a commercial OCXO, that I can use as a basic frequency reference. Then later on I'll decide if I really need anything better. Thanks, -- Phil. lists at philpem.me.uk http://www.philpem.me.uk/ From connie.marshall at suddenlink.net Mon Aug 11 18:08:30 2008 From: connie.marshall at suddenlink.net (Connie Marshall) Date: Mon, 11 Aug 2008 17:08:30 -0500 Subject: [time-nuts] TBolt and Z3801A performance data In-Reply-To: <489DFDCF.8060408@febo.com> Message-ID: Thanks John... good report! 73 Connie -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of John Ackermann N8UR Sent: Saturday, August 09, 2008 3:28 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] TBolt and Z3801A performance data I just put the results of some tests of 2 "Time-Nuts Special" Thunderbolts, as well as 2 Z3801As, at http://www.febo.com/pages/gpsdo_comparison/ I learned an interesting (and important) lesson in doing these measurement. I initially measured the pairs of GPSDO against each other (e.g., one TBolt as "reference" and the other TBolt as "DUT"). In theory, if the two oscillators are identical, and if their noise is uncorrelated, the results of the pair can be used to deduce the results of the individual units. However, in this case doing so gave a very optimistic view -- the TBolts were better than the pair of Z3801As! Another set of measurements comparing the GPSDOs against an independent reference revealed that the first measurement was a lie. I guess you can think of it like this. Picture two OCXOs that both age at the same rate and in the same direction. Because they drift together, measuring their relative phase hides their actual drift and makes them look better than they are. On the other hand, if they were drifting in opposite directions, they would look worse than they are. An identical aging trend is a "correlation" even though it's external to the things we usually think of. 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 bruce.griffiths at xtra.co.nz Mon Aug 11 19:28:48 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Tue, 12 Aug 2008 11:28:48 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A0A0EC.8080003@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> <489FB178.78A9653A@cox.net> <48A0A0EC.8080003@philpem.me.uk> Message-ID: <48A0CB30.5010002@xtra.co.nz> Philip > I dismissed the ELV's mechanical design based on the fact that it was two > BC337 (read: low power) transistors mounted on each side of the crystal, with > a cheap thermistor on top. No real thermal load at all -- as soon as the > transistors turn on, the temperature is likely to shoot WAY, WAY up, then > drop FAST when the transistors are turned off. The comparator-based > thermostat-type temperature control isn't likely to make that much easier > either. > > Thermal gradients in the vicinity of the crystal will be quite high. > Apparently the oscillator circuit is quite badly designed too (based on > information at http://glowbug.nl/projects/M51.html). Badly biased output > transistors and mismatched xtal load capacitance mainly. > Not to mention the low isolation buffer amplifier with relatively high phase noise. Extracting the signal through the crystal is a good method for ensuring a low phase noise floor. Ignore the misguided comments in the literature and on the web that say otherwise. Their calculations indicate a phase noise floor 20dB or more higher than that achieved in practice. This is the result of applying an standard equation to a situation where the assumptions implicit in its derivation don't hold. > > Second it does not take much to get parts in 10^-7 range. Temperature > > compensated crystal oscillators easily handle that level. With care, a > > crystal oscillator in a well designed circuit can reach parts in 10^-8 > > with a bit-bang oven control. HP did that in the late 1950's. From > > that point the difficulty is logarithmic. > > It certainly seems that way... > Nice to know it's not quite as hard as it looks. The ELV is specced at > 2x10^-8 stability and uses an AT-cut HC49U fundamental-mode parallel-resonant > crystal. I don't have the specs for the crystal cut used for my 10MHz xtals, > but I do know the base specifications are almost identical to the ELV unit's > crystal. > > I should probably mention the main reason I wanted to use the PIC control -- > so I can adjust the oven parameters (desired temperature, PID variables, and > so on) in real time, and read off the oven status at the same time (current > temperature, target temperature, last warmup time, hours run since last power > cycle, total crystal age, starting temperature, crystal oscillator state, and > so on). Obviously the turning point for each crystal isn't going to be > exactly 50.0000000... Celsius, so being able to hook up a high-resolution > counter and figure out what the exact turning point is and program the > thermal management kit with that would be useful. > > You'll need a really stable reference for the counter to get close to the turning point. Don't ramp the temperature too quickly as AT crystals are also sensitive to thermal transients. > In truth this is more a research and learning exercise. It'd just be nice to > end up with something that compares reasonably well to a commercial OCXO, > that I can use as a basic frequency reference. Then later on I'll decide if I > really need anything better. > > Thanks, > Bruce From bruce.griffiths at xtra.co.nz Mon Aug 11 19:33:28 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Tue, 12 Aug 2008 11:33:28 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A0CC48.1000100@xtra.co.nz> Mark Sims wrote: > For your temperature sensor and/or ADC consider the Analog Devices AD537 voltage to frequency converter chip. It has an onboard temperature sensor or could be interfaced to a thermistor, etc. The on chip sensor has a fairly large thermal mass. If you need instantaneous response to temperature use a very small thermistor. > > Since the output is frequency, any time nut worth his/her/its salt should be able to come up with a suitable counter circuit. One system that I did had the V/F freq set around 200 Hz. Counting a 16 MHz clock over 256 cycles of V/F waveform yielded microdegree resolution. > ---------------------------------------- > > Mark The AD537 has too much drift and too little sensitivity to reliably maintain the oven temperature (at the sensor) to within a few millidegrees. The internal dissipation of other circuitry within the chip will increase the sensor temperature offset from the temperature being measured. A thermistor bridge is a better idea as it can have high stability and sensitivity (about 10x that of an RTD). Bruce From holrum at hotmail.com Mon Aug 11 20:40:13 2008 From: holrum at hotmail.com (Mark Sims) Date: Tue, 12 Aug 2008 00:40:13 +0000 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: What you can do is calibrate the AD537/sensor(if used)/freq counter as a unit. Things like temperature offsets, chip dissipations, oscillator shifts, component tempcos, widget wiggles, etc. get compensated for. Ideally in an ocxo you would want the sensor and freq counter in the oven (or at least the freq counter reference oscillator). Hmmm, could get wickedly interesting if you clocked the freq counter with the OCXO output you were controlling. In one system we used a 20th order polynomial to do the conversion from reading to temperature. After a couple of years in the field (actually under the field) they retrieved, the data was dumped, and a new calibrations were done. The calibrations had typically shifted less than 100 microdegrees... and that was with a crappy oscillator in the freq counter. As far as sensitivity... a lower res unit (around 0.01 degree resolution) could easily detect the body heat from people in the lab. From temperature gradients you could reliably count people entering and leaving (a couple of particularly ample people counted as two bodies). ---------------------------------------- The AD537 has too much drift and too little sensitivity to reliably maintain the oven temperature (at the sensor) to within a few millidegrees. The internal dissipation of other circuitry within the chip will increase the sensor temperature offset from the temperature being measured. A thermistor bridge is a better idea as it can have high stability and sensitivity (about 10x that of an RTD). _________________________________________________________________ Get more from your digital life. Find out how. http://www.windowslive.com/default.html?ocid=TXT_TAGLM_WL_Home2_082008 From dforbes at dakotacom.net Mon Aug 11 22:06:00 2008 From: dforbes at dakotacom.net (David Forbes) Date: Mon, 11 Aug 2008 19:06:00 -0700 Subject: [time-nuts] Seriously vintage time nut Message-ID: Here's a fellow using a BIG tuning fork frequency standard in 1929 for some industrial data acquisition system using 16mm movie film as the medium... http://www.shorpy.com/node/4218?size=_original Then feel free to look at all the photos on the site - they're fascinating. -- --David Forbes, Tucson, AZ http://www.cathodecorner.com/ From bill at iaxs.net Tue Aug 12 00:42:16 2008 From: bill at iaxs.net (Bill Hawkins) Date: Mon, 11 Aug 2008 23:42:16 -0500 Subject: [time-nuts] Seriously vintage time nut In-Reply-To: References: Message-ID: <002201c8fc35$cbef1a10$021ba8c0@cyrus> Looks like a straight 8 gas engine on the stand. Hard to tell scaling from the hand. The hand looks graceful, like a woman's hand. So, why is the big vibrating apparatus not level? Looks like it has a granite block supported by four flat springs inside the box. Sure is nice to be reminded of the early days of technology when most of this list is about bleeding edge stuff. Bill Hawkins -----Original Message----- From: David Forbes Sent: Monday, August 11, 2008 9:06 PM Here's a fellow using a BIG tuning fork frequency standard in 1929 for some industrial data acquisition system using 16mm movie film as the medium... http://www.shorpy.com/node/4218?size=_original Then feel free to look at all the photos on the site - they're fascinating. -- From bruce.griffiths at xtra.co.nz Tue Aug 12 02:06:58 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Tue, 12 Aug 2008 18:06:58 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F6169.30301@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> Message-ID: <48A12882.3000205@xtra.co.nz> Philip The attached circuit schematic is for a 10MHz oscillator using a fundamental mode AT cut crystal. The problem with using a common base buffer with a fundamental mode crystal is that the crystal ESR is rather low so that the real component of the CB stage input impedance is not much less than that of the crystal. This reduces the crystal loaded Q significantly unless the common base stage is run at a high collector current which increases the CB stage output current noise. The crystal buffer shown here (Q103+Q104) reduces the real part of the input buffer stage input impedance to a value much less than the ESR of the crystal without using a large collector current. The oscillator transistor is in a Colpitts configuration. The transistor is only on for part of the cycle. The resistor (R102) connected between the emitter and C101+C102 junction reduces the phase noise of Q101 when it is on. The crystal current is determined by the dc collector current of Q101 and can be varied by adjusting R103. R103 is adjusted to set the crystal current to about 1.8mA (+13dBm output in a 50 ohm load.) The output stage uses an 18V supply so that it can drive an open circuit load without saturating the output transistor. This supply voltage can be reduced if a differential CB output stage is used OR 1) The output device is allowed to saturate when driving a high impedance load 2) The output transformer turns ratio is reduced 3) A lower output than +13dBm is acceptable. Since the phase noise floor is determined by the phase noise floor of the buffer amplifier some care has been taken to ensure that the buffer amplifier phase noise floor is low. Power supply noise will increase the phase noise of the amplifier and oscillator so a low noise power supply is essential. At low offset frequencies the crystal and the oscillator stage start to contribute to the phase noise. Thus the oscillator phase noise also needs to be low for low phase noise close to the carrier. It can be advantageous to use transistors with low collector base capacitances as their PM and AM noise can be made very low with RF feedback. The major source of flicker PM and flicker AM noise in an amplifier is modulation of the various device capacitances by low frequency noise currents or voltages. Thus low noise power supplies and low noise components should be used. Only use metal film or thin film resistors. No thick film, carbon resistor, metal oxide resistor should be used as they have significant flicker noise when a dc current is flowing through them. All coupling caps should be NP0/C0G or equivalent. Bruce -------------- next part -------------- A non-text attachment was scrubbed... Name: OCXO.gif Type: image/gif Size: 48363 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080812/7fa8dc71/attachment-0001.gif From hmurray at megapathdsl.net Tue Aug 12 14:36:57 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Tue, 12 Aug 2008 11:36:57 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge Message-ID: <20080812183658.C1D36BCCB@ip-64-139-1-69.sjc.megapath.net> I've got a couple of GPS units that use the SiRF chips feeding NTP. I was looking for low cost units for time keeping. They don't work very well. The time offset of the NMEA message wanders/jitters by about 100 ms. I can easily correct for a constant offset, but I can't dance around an offset that won't hold still. (Oh, well. I tried.) But I still have a couple of them collecting data. They seem to get confused by leap seconds. At least that's the only thing I can think of that changed recently. Here is a graph: http://www.megapathdsl.net/~hmurray/ntp/leap-gps3.gif It started, midnight, July 31. Does anybody know when the leap second announcement hit the satellites? I assume it's a software bug. Looks like it repeats on a weekly pattern. The red line on the top is a sane unit used as a reference to show that the time on the local system time isn't bouncing around. Here is a longer time span that shows a hanging bridge type pattern on the offset: http://www.megapathdsl.net/~hmurray/ntp/leap-gps2.gif If you were (un)lucky, you could get fooled into thinking that the offset was reasonably stable. This graph includes a few more units: http://www.megapathdsl.net/~hmurray/ntp/leap-gps.gif The spikes on the blue Garmin GPS 18 LVC usually happen when it is recovering from not-enough satellites. (I haven't checked these particular samples. That's what I found the last time I investigated.) -- These are my opinions, not necessarily my employer's. I hate spam. From chris.kuethe at gmail.com Tue Aug 12 15:03:47 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Tue, 12 Aug 2008 12:03:47 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: <20080812183658.C1D36BCCB@ip-64-139-1-69.sjc.megapath.net> References: <20080812183658.C1D36BCCB@ip-64-139-1-69.sjc.megapath.net> Message-ID: <91981b3e0808121203m5a7da16y70988f4eb31a4e5d@mail.gmail.com> On Tue, Aug 12, 2008 at 11:36 AM, Hal Murray wrote: > > I've got a couple of GPS units that use the SiRF chips feeding NTP. I was > looking for low cost units for time keeping. They don't work very well. The > time offset of the NMEA message wanders/jitters by about 100 ms. I can > easily correct for a constant offset, but I can't dance around an offset that > won't hold still. (Oh, well. I tried.) Yep, that's to be expected, given the iterative solver they're using. Try turning on the ZDA message, apparently the $ sign is aligned to the start of the second ... if its implemented in your version of firmware. Since you're running a BU-353 you could have all kinds of broken things in your firmware (not impressed by Globalsat). > But I still have a couple of them collecting data. As an aside, how and what are you collecting? I'm starting to think about setting up different loggers to catch the leap second... > They seem to get confused by leap seconds. At least that's the only thing I > can think of that changed recently. Here is a graph: > http://www.megapathdsl.net/~hmurray/ntp/leap-gps3.gif > > It started, midnight, July 31. Does anybody know when the leap second > announcement hit the satellites? first notice of this in the archives is on the 28th... so probably 0000h UTC on the 29th. > I assume it's a software bug. Looks like it repeats on a weekly pattern. > > The red line on the top is a sane unit used as a reference to show that the > time on the local system time isn't bouncing around. I've used the LVC w/ PPS as the reference clock... not sure that I trust the delay/jitter characteristics of USB enough to give me better time than a wrist-watch. > Here is a longer time span that shows a hanging bridge type pattern on the > offset: > http://www.megapathdsl.net/~hmurray/ntp/leap-gps2.gif > If you were (un)lucky, you could get fooled into thinking that the offset was > reasonably stable. > > This graph includes a few more units: > http://www.megapathdsl.net/~hmurray/ntp/leap-gps.gif > The spikes on the blue Garmin GPS 18 LVC usually happen when it is recovering > from not-enough satellites. (I haven't checked these particular samples. > That's what I found the last time I investigated.) it's "nice" to see all 3 SiRF receivers failing in the same way. that does make me think it's firmware rather than busted hardware. -- GDB has a 'break' feature; why doesn't it have 'fix' too? From bg at lysator.liu.se Tue Aug 12 16:08:28 2008 From: bg at lysator.liu.se (=?ISO-8859-1?Q?Bj=F6rn?= Gabrielsson) Date: Tue, 12 Aug 2008 22:08:28 +0200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <489F6169.30301@philpem.me.uk> References: <489F6169.30301@philpem.me.uk> Message-ID: <1218571709.2113.5.camel@bg-desktop> Hi Philip, On Sun, 2008-08-10 at 22:45 +0100, Philip Pemberton wrote: > As far as temperature regulation goes, I'm going to use a PIC > microcontroller (one of the 8-pin chips with an A/D converter) to monitor the > temperature of the crystal, and use a PID loop to control the two power > transistors to maintain a temperature of 50C +/- 2 Celsius (the accuracy spec > of the temperature sensor). I also have other higher-accuracy sensors (Dallas > DS18S20 and DS18B20) that I can calibrate with; these are accurate to around > half a degree Celsius with a resolution of 0.5C. Here is an example of a kind of synthetic TCXO using Dallas temp sensors. http://www.ijs.si/time/temp-compensation/ The resolution of the DS18x20-sensors are better than 0.5C. -- Bj?rn From dforbes at dakotacom.net Tue Aug 12 16:22:52 2008 From: dforbes at dakotacom.net (David Forbes) Date: Tue, 12 Aug 2008 13:22:52 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: <20080812183658.C1D36BCCB@ip-64-139-1-69.sjc.megapath.net> References: <20080812183658.C1D36BCCB@ip-64-139-1-69.sjc.megapath.net> Message-ID: <48A1F11C.5030108@dakotacom.net> Hal Murray wrote: > I've got a couple of GPS units that use the SiRF chips feeding NTP. I was > looking for low cost units for time keeping. They don't work very well. The > time offset of the NMEA message wanders/jitters by about 100 ms. I can > easily correct for a constant offset, but I can't dance around an offset that > won't hold still. (Oh, well. I tried.) > I looked into using some US GlobalSat units for my scope clock instead of the higher-priced GPS 18 LVC. The one I tried has an RS-232 serial port. The manual refers obliquely to a 1PPS capability, but unfortunately they didn't pin out the 1PPS signal to the board connector. I guess that their market is automotive navigation or logging, so they didn't consider it worth their while to add the 1PPS signal. I got the impression that the extra $50 you pay for the Garmin receiver is money well spent on a well-engineered device. From chris.kuethe at gmail.com Tue Aug 12 16:43:17 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Tue, 12 Aug 2008 13:43:17 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: <48A1F11C.5030108@dakotacom.net> References: <20080812183658.C1D36BCCB@ip-64-139-1-69.sjc.megapath.net> <48A1F11C.5030108@dakotacom.net> Message-ID: <91981b3e0808121343v257442d5r33a5117efcbcee16@mail.gmail.com> On Tue, Aug 12, 2008 at 1:22 PM, David Forbes wrote: > I looked into using some US GlobalSat units for my scope clock instead of the > higher-priced GPS 18 LVC. The one I tried has an RS-232 serial port. The manual > refers obliquely to a 1PPS capability, but unfortunately they didn't pin out the > 1PPS signal to the board connector. I guess that their market is automotive > navigation or logging, so they didn't consider it worth their while to add the > 1PPS signal. i've noticed that quite a number of globalsat modules at least hook up the 1PPS output from the chip to a test point - TP10. If you don't mind soldering, you could probably tap that output yourself.... not that you should have to. > I got the impression that the extra $50 you pay for the Garmin receiver is money > well spent on a well-engineered device. or a ublox, or a trimble, or... always check the datasheet -- GDB has a 'break' feature; why doesn't it have 'fix' too? From pico.2008 at sbcglobal.net Tue Aug 12 17:27:06 2008 From: pico.2008 at sbcglobal.net (Peter Putnam) Date: Tue, 12 Aug 2008 14:27:06 -0700 Subject: [time-nuts] Crystal Drive Level Message-ID: <48A2002A.1000507@sbcglobal.net> Greetings... I have a well-specified quartz crystal: Bliley BG71A (vintage mid 70's ?) 3.000 000 MHz parallel resonant, 100 pF 80 deg C tempco of <1.5/10e7/deg C over range 79 to 81 deg C in a glass enclosure with 9-pin miniature tube base that I would like to utilize in an oscillator circuit such as the one proposed by Bruce Griffith in his note to this list on 8/11/2008. How can I determine the crystal drive level and be certain that the drive level specified as "10 microwatts into10 ohms" will not be exceeded? Regards, Peter From bruce.griffiths at xtra.co.nz Tue Aug 12 18:37:46 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 13 Aug 2008 10:37:46 +1200 Subject: [time-nuts] Crystal Drive Level In-Reply-To: <48A2002A.1000507@sbcglobal.net> References: <48A2002A.1000507@sbcglobal.net> Message-ID: <48A210BA.4040107@xtra.co.nz> Peter Putnam wrote: > Greetings... > > I have a well-specified quartz crystal: > > Bliley BG71A > (vintage mid 70's ?) > 3.000 000 MHz > parallel resonant, 100 pF > 80 deg C > tempco of <1.5/10e7/deg C over range 79 to 81 deg C > in a glass enclosure with 9-pin miniature tube base > > that I would like to utilize in an oscillator circuit such as the one > proposed by Bruce Griffith in his note to this list on 8/11/2008. > > How can I determine the crystal drive level and be certain that the > drive level specified as "10 microwatts into10 ohms" will not be exceeded? > > Regards, > Peter > Peter 10 microwatts in 10 ohms corresponds to a crystal current of 1 mA. The question is is this an absolute limit or a recommended drive level? If it is a maximum then you should operate with a crystal current somewhat below this. Thus all you have to do is ensure that the crystal current is 1mA or less. It would be helpful to know the crystal ESR and if it is a fundamental or an overtone crystal. If its an AT cut fundamental crystal the ESR may be as high as 40 ohms or more. In which case the first stage of the oscillator buffer can be simplified to a common base stage. An AGC loop sensing the crystal current and comparing it with a reference voltage can easily be added. Another CB stage could be driven by the other end of T101's secondary and a 1K impedance load used at its collector output. An emitter follower could then be used to drive an RF detector for the AGC loop. Alternatively one could use a configuration with a high input impedance buffer as in Wenzel's circuit and drive the AGC (or monitor the level) from the buffer output. Its not too difficult to arrange for such a buffer to drive a cascade of common base stages to achieve a very high reverse isolation with relatively low distortion. However a few RF transformers are required. Using a buffer amplifier transistor with a resistive collector load is a bad idea (unless the resistor is shunted by an inductor or the primary of a transformer) as it significantly increases the phase noise of the amplifier over that which is possible with an optimised buffer amplifier design. I'll post another version of the crystal oscillator circuit in a day or so that utilises the alternative high impedance buffer circuit driving a CB cascade. It will also include AGC. Another possibility is to use the Driscoll two stage oscillator where the crystal current is limited by setting the collector current of the second stage. The second stage is driven into cutoff limiting the RF collector current of the first stage which is equal to the crystal current. However this circuit will significantly degrade the crystal Q unless the crystal ESR is relatively high (~40 ohms or more). Variants of this circuit which use AGC instead of cutoff to limit the crystal current are also possible. Another technique is to use diodes to clamp the oscillator output stage collector RF voltage peaks thus limiting the crystal current. For some variants of such Driscoll oscillators see: http://www.ko4bb.com/~bruce/XTALOSC.html NB using a LED in an oven may be somewhat problematic, so a different low noise method of biasing the various transistors may be required. Bruce From peterawson at earthlink.net Tue Aug 12 18:44:05 2008 From: peterawson at earthlink.net (Pete) Date: Tue, 12 Aug 2008 16:44:05 -0600 Subject: [time-nuts] Crystal Drive Level References: <48A2002A.1000507@sbcglobal.net> Message-ID: <001601c8fccc$f10454e0$0200a8c0@BASE1> Peter, Bruce's text explains that R103 sets the crystal current to about 1.8mA. This setting would result in operating a 10 ohm crystal at about 32uW. You would have to adjust R103 to yield about 1mA through your 10 ohm crystal. Pete Rawson From bruce.griffiths at xtra.co.nz Tue Aug 12 18:53:43 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 13 Aug 2008 10:53:43 +1200 Subject: [time-nuts] Crystal Drive Level In-Reply-To: <001601c8fccc$f10454e0$0200a8c0@BASE1> References: <48A2002A.1000507@sbcglobal.net> <001601c8fccc$f10454e0$0200a8c0@BASE1> Message-ID: <48A21477.6090802@xtra.co.nz> Pete wrote: > Peter, > > Bruce's text explains that R103 sets the crystal current to > about 1.8mA. This setting would result in operating a 10 ohm > crystal at about 32uW. You would have to adjust R103 to > yield about 1mA through your 10 ohm crystal. > > Pete Rawson > > Pete 1) The 3 MHz crystal ESR almost certainly isn't 10 ohms. The specification is actually for no more than 10 microwatts dissipated in a 10 ohm resistor connected in series with the crystal. This is a convenient way of monitoring the crystal current but the 10 ohm resistor shouldn't be permanently connected in series with the crystal as it degrades the Q. 2) The value of R103 needs to be adjusted to achieve the required output. The value required depends on the values of C101 and C102. Start with a high value for R103 (use a pot) and adjust the value until the required output is achieved. Measure the resistance of the pot and replace it with a fixed value resistor. Alternatively an AGC circuit could be used to regulate the crystal current by adjusting the base current of the oscillator transistor. Bruce From hmurray at megapathdsl.net Tue Aug 12 19:11:24 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Tue, 12 Aug 2008 16:11:24 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: Message from "Chris Kuethe" of "Tue, 12 Aug 2008 13:43:17 PDT." <91981b3e0808121343v257442d5r33a5117efcbcee16@mail.gmail.com> Message-ID: <20080812231125.4C6E7BCCB@ip-64-139-1-69.sjc.megapath.net> >> I got the impression that the extra $50 you pay for the Garmin receiver is money >> well spent on a well-engineered device. > or a ublox, or a trimble, or... always check the datasheet Does anybody have suggestions for low cost GPS units to use for timekeeping? No wiring preferred. The Garmin GPS 18 is the best candidate I know of. The LVC version includes PPS but requires minor soldering. The USB version doesn't have a PPS but it works reasonably well without any soldering. It's not supported by the officiall ntpd distributions, but I have a driver. It's not microsecond quality, but low milliseconds. The SiRF chipset is used in many low cost brands. Their latest version, III, is much more sensitive than the Garmin GPS 18. Most units I've seen are USB. Unfortunately, the NMEA output isn't well synchronized so it isn't very good for timekeeping. I took the cover off a BU-353. There is a PPS signal on the chip set, but no extra wire in the cable. It might be possible to free up the power return wire by using the shield. I haven't tried it. The Globalsat MR-350 is a RS-232 version with PPS. It comes with a funny connector and is slightly more expensive. It's easy to replace their connector. I haven't done detailed tests on the PPS. The NMEA signals are as crappy as all the other SiRF units. -- These are my opinions, not necessarily my employer's. I hate spam. From hmurray at megapathdsl.net Tue Aug 12 19:29:05 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Tue, 12 Aug 2008 16:29:05 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: Message from "Chris Kuethe" of "Tue, 12 Aug 2008 12:03:47 PDT." <91981b3e0808121203m5a7da16y70988f4eb31a4e5d@mail.gmail.com> Message-ID: <20080812232906.F1DFFBCCB@ip-64-139-1-69.sjc.megapath.net> > Yep, that's to be expected, given the iterative solver they're using. > Try turning on the ZDA message, apparently the $ sign is aligned to > the start of the second ... if its implemented in your version of > firmware. Since you're running a BU-353 you could have all kinds of > broken things in your firmware (not impressed by Globalsat). Do you expect the ZDA message to be better synchronized than any of the others? Is the BU-353 any better or worse than any of the other units using the SiRF chips? I've tried several different brands. I can't tell them apart unless I look at the physical package. > As an aside, how and what are you collecting? I'm starting to think > about setting up different loggers to catch the leap second... I just plug them into ntpd, use the noselect option on the server line, and turn on ntpd's statistics. > I've used the LVC w/ PPS as the reference clock... not sure that I > trust the delay/jitter characteristics of USB enough to give me better > time than a wrist-watch. USB isn't fundamentally evil. It's polled, so you won't get great response to something like a PPS interrupt. But the polling is handled automagically with modern hardware so It's not much worse (maybe better) than the typically interrupt batching that RS-232 chips do. I think USB will be good enough if your target is a few milliseconds rather than a few microseconds. -- These are my opinions, not necessarily my employer's. I hate spam. From newell at cei.net Tue Aug 12 20:18:27 2008 From: newell at cei.net (Scott Newell) Date: Tue, 12 Aug 2008 19:18:27 -0500 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: <20080812232906.F1DFFBCCB@ip-64-139-1-69.sjc.megapath.net> References: <20080812232906.F1DFFBCCB@ip-64-139-1-69.sjc.megapath.net> Message-ID: <200808130018.m7D0IWSg011151@host22.the-web-host.com> At 06:29 PM 8/12/2008, Hal Murray wrote: >USB isn't fundamentally evil. It's polled, so you won't get great response >to something like a PPS interrupt. But the polling is handled automagically >with modern hardware so It's not much worse (maybe better) than the typically >interrupt batching that RS-232 chips do. I wonder if using isochronous USB transfers would result in more consistent latency. -- newell N5TNL From chris.kuethe at gmail.com Tue Aug 12 20:25:28 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Tue, 12 Aug 2008 17:25:28 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: <200808130018.m7D0IWSg011151@host22.the-web-host.com> References: <20080812232906.F1DFFBCCB@ip-64-139-1-69.sjc.megapath.net> <200808130018.m7D0IWSg011151@host22.the-web-host.com> Message-ID: <91981b3e0808121725x7c895c2ep5a839a9c5a997f23@mail.gmail.com> On Tue, Aug 12, 2008 at 5:18 PM, Scott Newell wrote: > At 06:29 PM 8/12/2008, Hal Murray wrote: > >>USB isn't fundamentally evil. It's polled, so you won't get great response >>to something like a PPS interrupt. But the polling is handled automagically >>with modern hardware so It's not much worse (maybe better) than the typically >>interrupt batching that RS-232 chips do. Unless you configure your RS-232 chip to not batch interrupts... > I wonder if using isochronous USB transfers would result in more > consistent latency. It'd probably suck less, but you still have a trip up and down the usb protocol stack. And I haven't seen any usb-serial converters that do control lines properly... -- GDB has a 'break' feature; why doesn't it have 'fix' too? From chris.kuethe at gmail.com Tue Aug 12 20:38:07 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Tue, 12 Aug 2008 17:38:07 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: <20080812232906.F1DFFBCCB@ip-64-139-1-69.sjc.megapath.net> References: <91981b3e0808121203m5a7da16y70988f4eb31a4e5d@mail.gmail.com> <20080812232906.F1DFFBCCB@ip-64-139-1-69.sjc.megapath.net> Message-ID: <91981b3e0808121738q2931a9fbg239774f7f466662c@mail.gmail.com> On Tue, Aug 12, 2008 at 4:29 PM, Hal Murray wrote: >> Yep, that's to be expected, given the iterative solver they're using. >> Try turning on the ZDA message, apparently the $ sign is aligned to >> the start of the second ... if its implemented in your version of >> firmware. Since you're running a BU-353 you could have all kinds of >> broken things in your firmware (not impressed by Globalsat). > > Do you expect the ZDA message to be better synchronized than any of the > others? Yes. In SiRF receivers ZDA is specifically aligned to the second. I just checked my copy of the manual I got with my BU-353, and Table 1-1 NMEA Output Messages says "ZDA PPS timing message (synchronized to PPS)." RMC is produced after the navigation solution is computed and that does not happen in constant time. I found another little gem in my old email: the XTrac (High Sensitivity) version of the software does not support PPS. XTrac is often designated by "ES" in the version string. I also found that the PPS line is just a GPIO. Perhaps in the XTrac build they cut out the GPIO control code, but left in the scheduling of ZDA... *shrug* > Is the BU-353 any better or worse than any of the other units using the SiRF > chips? I've tried several different brands. I can't tell them apart unless > I look at the physical package. The hardware is about the same, but I don't trust Globalsat to not load some customized broken firmware... >> I've used the LVC w/ PPS as the reference clock... not sure that I >> trust the delay/jitter characteristics of USB enough to give me better >> time than a wrist-watch. > > USB isn't fundamentally evil. It's polled, so you won't get great response > to something like a PPS interrupt. But the polling is handled automagically > with modern hardware so It's not much worse (maybe better) than the typically > interrupt batching that RS-232 chips do. I know it's quick enough... usb ethernet, webcams, sound devices all work. But I don't think the usb implementation in most GPS receivers was designed to support timing applications. > I think USB will be good enough if your target is a few milliseconds rather > than a few microseconds. Yes, I've found that with a BU-303 (sirf2), using just NMEA timestamps, I can sync to about 5ms. Good enough for kerberos and nfs :) CK -- GDB has a 'break' feature; why doesn't it have 'fix' too? From bruce.griffiths at xtra.co.nz Tue Aug 12 21:51:45 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 13 Aug 2008 13:51:45 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <1218571709.2113.5.camel@bg-desktop> References: <489F6169.30301@philpem.me.uk> <1218571709.2113.5.camel@bg-desktop> Message-ID: <48A23E31.2000600@xtra.co.nz> Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. Bruce -------------- next part -------------- A non-text attachment was scrubbed... Name: OCXO_2.gif Type: image/gif Size: 44691 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080813/70229078/attachment-0001.gif From SAIDJACK at aol.com Tue Aug 12 23:16:48 2008 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Tue, 12 Aug 2008 23:16:48 EDT Subject: [time-nuts] Designing and building an OCXO and GPSDO Message-ID: Hi Bruce, do you have any phase noise/stability measurements for these circuits? thanks, Said In a message dated 8/12/2008 18:53:38 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. 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. **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 ) -------------- next part -------------- Hi Bruce, do you have any phase noise/stability measurements for these circuits? thanks, Said In a message dated 8/12/2008 18:53:38 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. Bruce [cid:X.MA1.1218597403 at aol.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. __________________________________________________________________ Looking for a car that's sporty, fun and fits in your budget? [1]Read reviews on AOL Autos. References 1. http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/gif Size: 44691 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080812/b7cff4c1/attachment-0001.gif From bruce.griffiths at xtra.co.nz Wed Aug 13 00:01:42 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 13 Aug 2008 16:01:42 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A25CA6.3040609@xtra.co.nz> SAIDJACK at aol.com wrote: > Hi Bruce, > > > > do you have any phase noise/stability measurements for these circuits? > > > > thanks, > Said > No, I have no way of measuring phase noise at present. Nor can I yet measure ADEV with adequate sensitivity and stability. However the phase noise floor can be estimated to within a few dB. Its even possible with some effort to estimate the phase noise of the buffer amplifiers in the flicker region. If low phase noise buffer designs are used the phase noise floor depends (for a CB input stage) on the buffer equivalent input current noise and the crystal current. With sufficient crystal current the phase noise floor can be very low (<-170dBc/Hz). A phase noise measurement system would be useful for optimising the close in phase noise. The circuits are intended to be somewhat better than a gate oscillator but without the complexity involved when AGC is used. The original request design was intended for a fundamental mode oven crystal the drift of which is unlikely to be very low. Nor will the Q of such a crystal be particularly high. With an overtone crystal a means of suppressing oscillation at unwanted overtones is required. Bruce From jim77742 at gmail.com Wed Aug 13 00:49:13 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 13 Aug 2008 14:49:13 +1000 Subject: [time-nuts] I want a good micro-controller Message-ID: Hi Folks, Well I have a nice idea in my head for a lunar occultation timer. Basically it's a normal clock that accepts a push button click and records the UTC of the events. Multiple events can be recorded and displayed back. The time must be settable and could also accept an external 1 PPS for accurate time setting. It also needs to be portable and battery powered. When it does get 1 PPS time setting it could work out how good its oscillator is an adjust for it. etc. etc. and etc. I have lots of other ideas in my head too and it's about time I settled down and thoroughly learned a decent micro controller. I want to pick one, get the stuff I need and commit to it. I've had experience with Atmel AT90S2313 but really want something with more memory, a decent number of io pins and I'd like to avoid assembler. It needs to drive a display of some form (standard LCD is fine but other options would be good) and since nearly all my references are based on 10MHz it would be nice if it could be clocked at that speed. I used to program the Acorn Achimedes and so ARM would be nice and since I'm a 20 year experienced C programmer (not C++) then that is what I'd like to program it in. Thoughts, ideas, comments would be appreciated! Oh and cheap! :-) Regards, Jim From bruce.griffiths at xtra.co.nz Wed Aug 13 01:57:34 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 13 Aug 2008 17:57:34 +1200 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: <48A277CE.3020400@xtra.co.nz> Jim Palfreyman wrote: > Hi Folks, > > Well I have a nice idea in my head for a lunar occultation timer. Basically > it's a normal clock that accepts a push button click and records the UTC of > the events. Multiple events can be recorded and displayed back. The time > must be settable and could also accept an external 1 PPS for accurate time > setting. It also needs to be portable and battery powered. When it does get > 1 PPS time setting it could work out how good its oscillator is an adjust > for it. etc. etc. and etc. > > I have lots of other ideas in my head too and it's about time I settled down > and thoroughly learned a decent micro controller. I want to pick one, get > the stuff I need and commit to it. I've had experience with Atmel AT90S2313 > but really want something with more memory, a decent number of io pins and > I'd like to avoid assembler. > > It needs to drive a display of some form (standard LCD is fine but other > options would be good) and since nearly all my references are based on 10MHz > it would be nice if it could be clocked at that speed. I used to program the > Acorn Achimedes and so ARM would be nice and since I'm a 20 year experienced > C programmer (not C++) then that is what I'd like to program it in. > > Thoughts, ideas, comments would be appreciated! > > Oh and cheap! > > :-) > > Regards, > > Jim > Jim Is this intended for field use? If so, one has to remember that it will not always be easy or practical to set up a GPS receiver on site. Provision for using the timer as an interpolation device to interpolate between timestamps obtained before and after the event from a fixed location reliable GPS receiver would greatly enhance its usefulness. Sometimes its hard enough to setup and acquire the star or other object of interest without having to worry about a GPS receiver as well. Bruce Bruce From jim77742 at gmail.com Wed Aug 13 02:05:31 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 13 Aug 2008 16:05:31 +1000 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A277CE.3020400@xtra.co.nz> References: <48A277CE.3020400@xtra.co.nz> Message-ID: Bruce, Yes that's exactly my plan. No GPS and designed for field use. A halfway decent crystal with interpolation from 1 PPS timestamps should provide decent results. And anything else I can dream up. Bottom line is I need to know which micro-controller to embrace. Thanks Didier for your suggestion. Any others? Jim 2008/8/13 Bruce Griffiths > Jim Palfreyman wrote: > > Hi Folks, > > > > Well I have a nice idea in my head for a lunar occultation timer. > Basically > > it's a normal clock that accepts a push button click and records the UTC > of > > the events. Multiple events can be recorded and displayed back. The time > > must be settable and could also accept an external 1 PPS for accurate > time > > setting. It also needs to be portable and battery powered. When it does > get > > 1 PPS time setting it could work out how good its oscillator is an adjust > > for it. etc. etc. and etc. > > > > I have lots of other ideas in my head too and it's about time I settled > down > > and thoroughly learned a decent micro controller. I want to pick one, get > > the stuff I need and commit to it. I've had experience with Atmel > AT90S2313 > > but really want something with more memory, a decent number of io pins > and > > I'd like to avoid assembler. > > > > It needs to drive a display of some form (standard LCD is fine but other > > options would be good) and since nearly all my references are based on > 10MHz > > it would be nice if it could be clocked at that speed. I used to program > the > > Acorn Achimedes and so ARM would be nice and since I'm a 20 year > experienced > > C programmer (not C++) then that is what I'd like to program it in. > > > > Thoughts, ideas, comments would be appreciated! > > > > Oh and cheap! > > > > :-) > > > > Regards, > > > > Jim > > > Jim > > Is this intended for field use? > If so, one has to remember that it will not always be easy or practical > to set up a GPS receiver on site. > Provision for using the timer as an interpolation device to interpolate > between timestamps obtained before and after the event from a fixed > location reliable GPS receiver would greatly enhance its usefulness. > Sometimes its hard enough to setup and acquire the star or other object > of interest without having to worry about a GPS receiver as well. > > Bruce > > > 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 jmiles at pop.net Wed Aug 13 04:23:33 2008 From: jmiles at pop.net (John Miles) Date: Wed, 13 Aug 2008 01:23:33 -0700 Subject: [time-nuts] I want a good micro-controller In-Reply-To: Message-ID: It's sort of a religious matter, but if you are looking for an easy-to-use part with great, free C/C++ support, you'd most likely be happy with the AtMEGA series. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Jim Palfreyman > Sent: Tuesday, August 12, 2008 11:06 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] I want a good micro-controller > > > Bruce, > > Yes that's exactly my plan. No GPS and designed for field use. A halfway > decent crystal with interpolation from 1 PPS timestamps should provide > decent results. And anything else I can dream up. > > Bottom line is I need to know which micro-controller to embrace. > > Thanks Didier for your suggestion. Any others? > > Jim > > From wje at quackers.net Wed Aug 13 07:00:16 2008 From: wje at quackers.net (wje) Date: Wed, 13 Aug 2008 07:00:16 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: <48A2BEC0.50004@quackers.net> My favorite for many uses is the Freescale MC68HC908QT4, or others in that series. Freescale provides a complete C development environment for free. The QT4 is an 8-pin package, with up to 6 I/O pins. I've used it for everything from a 555 timer replacement to the controller for an RPM meter, to the controller for a GPS/Rb/xtal freqency standard. Of course, for many purposes it doesn't particularly matter whose chip you use, as long as the tools are adequate. There are any number of choices, including the PIC line, which everyone but me seems to love. Bill Ezell ---------- They said 'Windows or better' so I used Linux. John Miles wrote: It's sort of a religious matter, but if you are looking for an easy-to-use part with great, free C/C++ support, you'd most likely be happy with the AtMEGA series. -- john, KE5FX -----Original Message----- From: [1]time-nuts-bounces at febo.com [[2]mailto:time-nuts-bounces at febo.com]On Behalf Of Jim Palfreyman Sent: Tuesday, August 12, 2008 11:06 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] I want a good micro-controller Bruce, Yes that's exactly my plan. No GPS and designed for field use. A halfway decent crystal with interpolation from 1 PPS timestamps should provide decent results. And anything else I can dream up. Bottom line is I need to know which micro-controller to embrace. Thanks Didier for your suggestion. Any others? Jim _______________________________________________ time-nuts mailing list -- [3]time-nuts at febo.com To unsubscribe, go to [4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts-bounces at febo.com 2. mailto:time-nuts-bounces at febo.com 3. mailto:time-nuts at febo.com 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From cupido at mail.ua.pt Wed Aug 13 07:23:41 2008 From: cupido at mail.ua.pt (Luis Cupido) Date: Wed, 13 Aug 2008 12:23:41 +0100 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A2BEC0.50004@quackers.net> References: <48A2BEC0.50004@quackers.net> Message-ID: <48A2C43D.8080800@mail.ua.pt> >There are any number of >choices, including the PIC line, which everyone but me seems to love. Bill, You're not alone ;-) Luis Cupido. ct1dmk. wje wrote: > My favorite for many uses is the Freescale MC68HC908QT4, or others in > that series. Freescale provides a complete C development environment > for free. The QT4 is an 8-pin package, with up to 6 I/O pins. I've used > it for everything from a 555 timer replacement to the controller for an > RPM meter, to the controller for a GPS/Rb/xtal freqency standard. Of > course, for many purposes it doesn't particularly matter whose chip you > use, as long as the tools are adequate. There are any number of > choices, including the PIC line, which everyone but me seems to love. > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > John Miles wrote: > > It's sort of a religious matter, but if you are looking for an easy-to-use > part with great, free C/C++ support, you'd most likely be happy with the > AtMEGA series. > > -- john, KE5FX > > > > -----Original Message----- > From: [1]time-nuts-bounces at febo.com [[2]mailto:time-nuts-bounces at febo.com]On > Behalf Of Jim Palfreyman > Sent: Tuesday, August 12, 2008 11:06 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] I want a good micro-controller > > > Bruce, > > Yes that's exactly my plan. No GPS and designed for field use. A halfway > decent crystal with interpolation from 1 PPS timestamps should provide > decent results. And anything else I can dream up. > > Bottom line is I need to know which micro-controller to embrace. > > Thanks Didier for your suggestion. Any others? > > Jim > > > > > _______________________________________________ > time-nuts mailing list -- [3]time-nuts at febo.com > To unsubscribe, go to [4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > References > > 1. mailto:time-nuts-bounces at febo.com > 2. mailto:time-nuts-bounces at febo.com > 3. mailto:time-nuts at febo.com > 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > _______________________________________________ > time-nuts mailing list -- 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 jherrero at hvsistemas.es Wed Aug 13 08:52:52 2008 From: jherrero at hvsistemas.es (Javier Herrero) Date: Wed, 13 Aug 2008 14:52:52 +0200 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A2C43D.8080800@mail.ua.pt> References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt> Message-ID: <48A2D924.3040809@hvsistemas.es> Luis Cupido escribi?: > >There are any number of > >choices, including the PIC line, which everyone but me seems to love. > > Bill, > You're not alone ;-) > > Luis Cupido. > ct1dmk. > I'm with both of yours... This is a recurrent discussion here, and there are some deep PIC lovers... but once I've used an ATtiny... I would never use a PIC again for a new design. And for those larger needs, any ARM7 outperforms the best PIC in price and performance :) Regards, Javier -- ------------------------------------------------------------------------ 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 holrum at hotmail.com Wed Aug 13 10:19:45 2008 From: holrum at hotmail.com (Mark Sims) Date: Wed, 13 Aug 2008 14:19:45 +0000 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: Well, I'm particularly fond of the MegaDonkey from mega-donkey.com It does everything I want a microcontroller to do (it should, I designed it). Atmel ATMEGA2561, 256K flash, 8K RAM, LCD 160x80 graphics touchscreen display, two serial ports, IIC ports, A/D ports, lots of I/O pins, beeper, prototyping area, wonderful open-source software, makes Julianne fries, gives a fair backrub. The softwware is in avr-gcc so you have a full blown C compiler. There is also a version with a Mega128 chip (128K flash,4K RAM, 128x64 LCD, mediocre backrubs) and one without the LCD. The software has a software time-of-day clock with crystal freq calibration capability. Has demo routines for digital and analog clock displays. Internally it runs off a 10 KHz interrupt so you can get that level of resolution. You could add a battery backed IIC clock chip (we have a couple of circuit boards floating around, haven't written the software yet). Also there is a 8 pin SOIC chip pad area in the prototyping area where a clock chip could be added). ---------------------------------------- _________________________________________________________________ Reveal your inner athlete and share it with friends on Windows Live. http://revealyourinnerathlete.windowslive.com?locale=en-us&ocid=TXT_TAGLM_WLYIA_whichathlete_us From jra at febo.com Wed Aug 13 10:27:28 2008 From: jra at febo.com (John Ackermann N8UR) Date: Wed, 13 Aug 2008 10:27:28 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: <48A2EF50.8050205@febo.com> Mark Sims wrote: > Well, I'm particularly fond of the MegaDonkey from mega-donkey.com It does everything I want a microcontroller to do (it should, I designed it). Atmel ATMEGA2561, 256K flash, 8K RAM, LCD 160x80 graphics touchscreen display, two serial ports, IIC ports, A/D ports, lots of I/O pins, beeper, prototyping area, wonderful open-source software, makes Julianne fries, gives a fair backrub. The softwware is in avr-gcc so you have a full blown C compiler. There is also a version with a Mega128 chip (128K flash,4K RAM, 128x64 LCD, mediocre backrubs) and one without the LCD. > > The software has a software time-of-day clock with crystal freq calibration capability. Has demo routines for digital and analog clock displays. Internally it runs off a 10 KHz interrupt so you can get that level of resolution. You could add a battery backed IIC clock chip (we have a couple of circuit boards floating around, haven't written the software yet). Also there is a 8 pin SOIC chip pad area in the prototyping area where a clock chip could be added). Mark, sounds very cool but www.mega-donkey.com or mega-donkey.com don't resolve... John From peterawson at earthlink.net Wed Aug 13 11:33:03 2008 From: peterawson at earthlink.net (Pete) Date: Wed, 13 Aug 2008 09:33:03 -0600 Subject: [time-nuts] I want a good micro-controller References: <48A2EF50.8050205@febo.com> Message-ID: <002301c8fd59$e2bea240$0200a8c0@BASE1> The URL works fine from here. Pete From SAIDJACK at aol.com Wed Aug 13 12:24:46 2008 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Wed, 13 Aug 2008 12:24:46 EDT Subject: [time-nuts] Designing and building an OCXO and GPSDO Message-ID: Thanks Bruce, it would be interesting to see how the different topologies affect phase noise and stability etc, and what kind of performance can be achieved. bye, Said In a message dated 8/12/2008 20:19:03 Pacific Daylight Time, SAIDJACK@ aol.com writes: Hi Bruce, do you have any phase noise/stability measurements for these circuits? thanks, Said In a message dated 8/12/2008 18:53:38 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. 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. **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut0005000000001 7 ) Hi Bruce, do you have any phase noise/stability measurements for these circuits? thanks, Said In a message dated 8/12/2008 18:53:38 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. Bruce [cid:X.MA1.1218597403 at aol.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. __________________________________________________________________ Looking for a car that's sporty, fun and fits in your budget? [1]Read reviews on AOL Autos. References 1. http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 ) -------------- next part -------------- Thanks Bruce, it would be interesting to see how the different topologies affect phase noise and stability etc, and what kind of performance can be achieved. bye, Said In a message dated 8/12/2008 20:19:03 Pacific Daylight Time, SAIDJACK at aol.com writes: Hi Bruce, do you have any phase noise/stability measurements for these circuits? thanks, Said In a message dated 8/12/2008 18:53:38 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. 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. **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000 50000000017 ) Hi Bruce, do you have any phase noise/stability measurements for these circuits? thanks, Said In a message dated 8/12/2008 18:53:38 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: Attached schematic is for a variant of the Wenzel circuit using a JFET high input impedance buffer to drive a cascaded pair of CB stages. L104 is approximately resonant with C111 at 3MHz so that either an RF choke and series resistor or a relative;y low value resistor (10K) can be used to set the JFET gate voltage. The impedance of C104 at 3MHz is about 530 ohms so a 1mA crystal current will result in about 530 mV rms across C104. An additional inductor can be used in series with the crystal to resonate out the input capacitance of the oscillator stage if required, this will allow a greater tuning range to be achieved. Inductor L104 needs to have a reasonably high Q ( > 100 @ 3MHz) to avoid degrading the loaded Q significantly. The drain current of JFET Q103 is determined by the collector current of Q104 this minimises the effect of JFET parameter variations from part to part on its drain current. The RF voltage at the source of Q103 can be amplified (a widebandwidth opamp could be used) and used to drive a detector diode for AGC purposes. Alternatively a common base stage connected to the other end of the secondary of T101 could be used an RF current source to drive a full wave diode detector with a low load resistance. This will largely eliminate the effect of the detector diode forward voltage drops on the detected output. This detector dc load current can than be compared with a reference current and the dc collector current of Q101 adjusted to regulate the crystal current. Bruce [cid:X.MA1.1218597403 at aol.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. __________________________________________________________________ Looking for a car that's sporty, fun and fits in your budget? [1]Read reviews on AOL Autos. References 1. http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut0005 0000000017 [cid:X.MA1.1218644679 at aol.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. __________________________________________________________________ Looking for a car that's sporty, fun and fits in your budget? [1]Read reviews on AOL Autos. References 1. http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/gif Size: 44691 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080813/3d96282f/attachment-0001.gif From hmurray at megapathdsl.net Wed Aug 13 13:08:47 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 13 Aug 2008 10:08:47 -0700 Subject: [time-nuts] I want a good micro-controller In-Reply-To: Message from wje of "Wed, 13 Aug 2008 07:00:16 EDT." <48A2BEC0.50004@quackers.net> Message-ID: <20080813170848.942D5BCCB@ip-64-139-1-69.sjc.megapath.net> > There are any number of choices, including the PIC line, which > everyone but me seems to love. Many years ago, Microchip was friendly to hobbyists so they collected a big fan club. -- These are my opinions, not necessarily my employer's. I hate spam. From hmurray at megapathdsl.net Wed Aug 13 14:50:53 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Wed, 13 Aug 2008 11:50:53 -0700 Subject: [time-nuts] I want a good micro-controller In-Reply-To: Message from "Jim Palfreyman" of "Wed, 13 Aug 2008 14:49:13 +1000." Message-ID: <20080813185054.3A974BCCB@ip-64-139-1-69.sjc.megapath.net> > It needs to drive a display of some form (standard LCD is fine but > other options would be good) and since nearly all my references are > based on 10MHz it would be nice if it could be clocked at that speed. > I used to program the Acorn Achimedes and so ARM would be nice and > since I'm a 20 year experienced C programmer (not C++) then that is > what I'd like to program it in. > Thoughts, ideas, comments would be appreciated! Are you looking for a chip to use in a board you are going to design, or an existing board that will do your job, possibly with some hacking? I'm not up to date on boards. The mega-donkey looks like a good straw man. (I think you need something else to program it.) Vendors often have inexpensive low end development kits. (Some of the high end boards are quite pricey for a hobby project.) Here is a sample: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=ATAVRDB101- ND (It needs a programmer too.) Have you considered using a laptop? Older (real old?) ones had printer ports so you could get a PPS in. Assuming you are looking for a chip: I know of 3 families of 8 bit chips: AVR from Atmel, PIC from Microchip, and 8051s from several vendors. It's a cut-throat market area. I think they all make chips that are roughly equivalent. If you need something more powerful, the ARM chips are probably the way to go. I like the Atmel chips, both ARM and AVR. Their I/O units are generally not too quirky and the documentation is pretty good. Digikey carries them. They usually have a one page sheet that compares all of their chips. Here is a sample, but it doesn't show the I/O stuff. http://www.atmel.com/products/AVR/default_picopower.asp > Oh and cheap! I don't think the price of the CPU chip will be a big deal for a low volume project. Things get interesting if you want to buy a million of them. Often, a vendor will make several versions of a chip with the same I/O but different sizes of RAM/Flash. For a hobby project, I'd get the biggest one, just in case. Odds and ends: If you have a PPS, you probably have 10 MHz too. If you can use that for your CPU clock, then you don't have to worry about calibration. Running off batteries won't be a problem. All your power will go into the backlight for the LCD. :) -- These are my opinions, not necessarily my employer's. I hate spam. From holrum at hotmail.com Wed Aug 13 16:04:21 2008 From: holrum at hotmail.com (Mark Sims) Date: Wed, 13 Aug 2008 20:04:21 +0000 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: Hello Hal, The MegaDonkey can be programmed in one of three ways: 1) the on board bootloader via either of the onboard RS-232 ports (or use a USB-RS232 dongle). The bootloader is VERY fast (over 10Kb/sec... about as fast as the chip can write it's flash memory). One neat feature of the system is the ability to echo all the screen drawing commands/touchscreen to a host PC. You can remotely control the unit via a wireless dongle or not use an on-board LCD screen. The serial ports match standard PC ports. You use a null modem cable to connect it to a PC. 2) via the Atmel standard ISP (10 pin) connector. Any standard ATMEL programmer can be used. 3) via the Atmel standard JTAG port. You can use the ATMEL JTAG-ICE device for programming and debugging (but it is always best not to put bugs in your program to start with ;-) ) Although Atmel's programmers and JTAG ICE are nice, I MUCH prefer the bootloader approach. Atmel's programmers can be a bit cumbersome and finicky about establishing connections to their processors. If you are developing commercial applications we have a high-grade crypto bootloader available (DES, 3DES, AES256, XTEA). The software is all written in C. We deliberately try to use as little of the language as possible... makes it easier for non-gurus to understand. We used the avg-gcc compiler in the popular free, open source WIN-AVR package. This compiler integrates very well with Atmel's free AVR Studio development environment (if you like developing in an IDE environment). ---------------------------------------- >I'm not up to date on boards. The mega-donkey looks like a good straw man. >(I think you need something else to program it.) ---------------------------------------- _________________________________________________________________ Get Windows Live and get whatever you need, wherever you are. Start here. http://www.windowslive.com/default.html?ocid=TXT_TAGLM_WL_Home_082008 From newell at cei.net Wed Aug 13 16:10:50 2008 From: newell at cei.net (Scott Newell) Date: Wed, 13 Aug 2008 15:10:50 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: <200808132011.m7DKB3RE000814@mail960c35.nsolutionszone.com> At 03:04 PM 8/13/2008 , Mark Sims wrote: >approach. Atmel's programmers can be a bit cumbersome and finicky about establishing connections to their processors. No kidding! I'm hacking on the new HP 20B financial calculator (think of it as a $40 AT91SAM7L128 demo board), and that SAMBA program takes 15 minutes (!) to dump or program 128k flash through the serial port. When it decides to connect, that is. My hacked up OpenOCD script does it in less than 30s through JTAG. -- newell N5TNL From bruce.griffiths at xtra.co.nz Wed Aug 13 18:13:32 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 14 Aug 2008 10:13:32 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A35C8C.3020201@xtra.co.nz> SAIDJACK at aol.com wrote: > Thanks Bruce, > > > > it would be interesting to see how the different topologies affect > phase noise and stability etc, and what kind of performance can be > achieved. > > > > bye, > > Said > Said When the output signal is filtered by the crystal, the phase noise floor is independent of the particular oscillator design. The phase noise floor only depends on the phase noise of the buffer amplifier. Techniques for designing low phase noise buffer amplifiers are well established. Basically the idea is to keep the dc and low frequency noise at the buffer amplifier output low and use RF negative feedback to stabilise the buffer amplifier gain (reduces flicker phase noise). Thus low power supply noise is required (it modulates amplifier phase shift and thus contributes to phase noise). For offsets within the crystal bandwidth, intrinsic crystal flicker noise contributes to the phase noise as does the phase noise of the oscillator active components. The oscillator can be run in class A if AGC is used, RF negative feedback can then be used to reduce the sustaining circuit phase noise. A Colpitts crystal oscillator typically operates in Class C with a small duty cycle, the transistor should never saturate. Thus with carefully optimised buffer amplifiers and a fixed crystal current and the same crystal, the various circuits should only differ substantially in their flicker phase noise characteristics. In a well designed circuit the stability will be largely determined by component quality, amplitude stability and residual temperature fluctuations. Without some stabilising RF negative feedback the flicker phase noise will be relatively high, however the transistor is on for part of the cycle which tends to reduce the phase noise. Using a 100k resistor from the FET gate to ground isnt exactly conducive to a low phase noise floor unless the amplitude of the signal at the gate is large. It would certainly be useful to evaluate the phase noise of the various oscillator circuits particularly in the flicker phase noise region as well as ADEV as a function of time. Bruce From bruce.griffiths at xtra.co.nz Wed Aug 13 19:01:23 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 14 Aug 2008 11:01:23 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A367C3.3010405@xtra.co.nz> SAIDJACK at aol.com wrote: > Thanks Bruce, > > > > it would be interesting to see how the different topologies affect > phase noise and stability etc, and what kind of performance can be > achieved. > > > > bye, > > Said > > > Said One way to evaluate the merits of various oscillator circuits would be to build an example of each and then measure their phase noise and ADEV. To keep the number of variables and costs down all oscillators should use the same 10MHz fundamental crystal. The oscillators should not be enclosed in their own oven, however an enclosure with a long thermal time constant can be used. The oscillator output should be +7dBm into 50 ohms. No EFC and probably no trimmer cap (however this requires that a TSC5120A or similar be used to measure the ADEVand phase noise). Power supply should be standardised at +12V. Bruce From cupido at mail.ua.pt Wed Aug 13 19:22:54 2008 From: cupido at mail.ua.pt (Luis Cupido) Date: Thu, 14 Aug 2008 00:22:54 +0100 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <200808132011.m7DKB3RE000814@mail960c35.nsolutionszone.com> References: <200808132011.m7DKB3RE000814@mail960c35.nsolutionszone.com> Message-ID: <48A36CCE.9070203@mail.ua.pt> Another view ! I found myself going in another direction recently... PC104 :-) ... Designing a board for a really small think, one's favorite either PIC 51's ATmel freescale or whatever seems to be fine. A small demo board or existing PCB from some vendors seems fine to me also. but when it comes to a medium to high power thing lets say in the ARM category and above, it becomes a lot easier to use a PC104 board. Specially because those pop-up on ebay at less than most of the kits and demo boards for uC that have 1/100 of the processing power. Not to mention the tools available that are the same as any for the PC architecture... Compilers assemblers etc... sky is the limit. ROM can be a compactFlash-ide disk, a few bucks you get 1Gb if you want, plus Ethernet, LCD/VGA USB LPT, 2xRS232 etc (depending on the specific model). For more complex things it just doesn't pay to make a specific PCB (unless for big qty business production)... Last year I got on ebay a few 233MHz Pentium PC104 with eth10/100 + 2xRS232 + lpt + 2xusb + Kb for 30euro each!!! What else could we do with that money ?! ;-) Ok fine they eat 5V at 800mA... not exactely low power... but there are better ones... my 2 cents ;-) Luis Cupido. ct1dmk. From SAIDJACK at aol.com Wed Aug 13 19:39:47 2008 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Wed, 13 Aug 2008 19:39:47 EDT Subject: [time-nuts] Designing and building an OCXO and GPSDO Message-ID: Yup, I agree. I wish I did have one of those TSC5120A's! Or "at least" an E5052A/B. bye, Said In a message dated 8/13/2008 16:03:00 Pacific Daylight Time, bruce.griffiths at xtra.co.nz writes: SAIDJACK at aol.com wrote: > Thanks Bruce, > > > > it would be interesting to see how the different topologies affect > phase noise and stability etc, and what kind of performance can be > achieved. > > > > bye, > > Said > > > Said One way to evaluate the merits of various oscillator circuits would be to build an example of each and then measure their phase noise and ADEV. To keep the number of variables and costs down all oscillators should use the same 10MHz fundamental crystal. The oscillators should not be enclosed in their own oven, however an enclosure with a long thermal time constant can be used. The oscillator output should be +7dBm into 50 ohms. No EFC and probably no trimmer cap (however this requires that a TSC5120A or similar be used to measure the ADEVand phase noise). Power supply should be standardised at +12V. 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. **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000017 ) From bruce.griffiths at xtra.co.nz Wed Aug 13 19:54:28 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 14 Aug 2008 11:54:28 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A37434.10702@xtra.co.nz> SAIDJACK at aol.com wrote: > Yup, I agree. > > I wish I did have one of those TSC5120A's! > > Or "at least" an E5052A/B. > > bye, > Said > > > Said Maybe a "competition" between various designs is in order? Restricting the designs to those reputed to have low phase noise and/or high stability is perhaps in order. We don't want endless slight variations on the same theme, significant design variations only would be useful in evaluating relative performance. Examples using general purpose and high ft transistors as well as modular amplifiers (perhaps only useful for 80MHz and above)? Bruce From jmiles at pop.net Wed Aug 13 19:57:16 2008 From: jmiles at pop.net (John Miles) Date: Wed, 13 Aug 2008 16:57:16 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: Message-ID: If you don't want pushbutton convenience, you can measure the close-in phase noise with not much more than a $5 mixer and $2 opamp. It will take a lot of "sweat equity," and you will need to build two of whatever you're measuring, or buy/borrow a known-cleaner source at the same frequency. TSC analyzers are great but they are not the only way to go. Actually their biggest advantages lie in their size/weight and the fact that the reference doesn't have to be at the same frequency as the DUT. Other than that, their performance is not necessarily better than a homebrew single-mixer quadrature PLL or an 11848A. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of SAIDJACK at aol.com > Sent: Wednesday, August 13, 2008 4:40 PM > To: time-nuts at febo.com > Subject: Re: [time-nuts] Designing and building an OCXO and GPSDO > > > Yup, I agree. > > I wish I did have one of those TSC5120A's! > > Or "at least" an E5052A/B. > > bye, > Said > > > In a message dated 8/13/2008 16:03:00 Pacific Daylight Time, > bruce.griffiths at xtra.co.nz writes: > > SAIDJACK at aol.com wrote: > > Thanks Bruce, > > > > > > > > it would be interesting to see how the different topologies affect > > phase noise and stability etc, and what kind of performance can be > > achieved. > > > > > > > > bye, > > > > Said > > > > > > > Said > > One way to evaluate the merits of various oscillator circuits would be > to build an example of each and then measure their phase noise and ADEV. > > To keep the number of variables and costs down all oscillators should > use the same 10MHz fundamental crystal. > The oscillators should not be enclosed in their own oven, however an > enclosure with a long thermal time constant can be used. > The oscillator output should be +7dBm into 50 ohms. > No EFC and probably no trimmer cap (however this requires that a > TSC5120A or similar be used to measure the ADEVand phase noise). > Power supply should be standardised at +12V. > > > 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. **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut00050000000 017 ) _______________________________________________ time-nuts mailing list -- 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 bob.paddock at gmail.com Wed Aug 13 20:06:47 2008 From: bob.paddock at gmail.com (Bob Paddock) Date: Wed, 13 Aug 2008 20:06:47 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A2D924.3040809@hvsistemas.es> References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt> <48A2D924.3040809@hvsistemas.es> Message-ID: > any ARM7 outperforms the best PIC in price and performance :) http://beagleboard.org/ Get them from DigiKey, $149. http://dkc1.digikey.com/us/mkt/beagleboard.html "The USB-powered Beagle Board is a low-cost, fan-less single board computer utilizing Texas Instruments' OMAP3530 [ARM] application processor that unleashes laptop-like performance and expansion without the bulk, expense, or noise of typical desktop machines. Beagle Board is based on an OMAP3530 application processor featuring an ARM(R) Cortex?-A8 running at up to 600MHz and delivering over 1,200 Dhrystone MIPS of performance via superscalar operation with highly accurate branch prediction and 256KB of L2 cache. Focal to Beagle Board experience is the high-speed USB 2.0 on-the-go (OTG) port that can be utilized to provide power to the board or to deliver highly flexible expansion. Standard PC peripherals can be connected to Beagle Board using the USB with a mini-A to standard-A cable adapter, DVI-D using an HDMI to DVI-D adapter, or through the MMC/SD/SDIO connector enabling a complete desktop experience." -- http://www.wearablesmartsensors.com/ http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/ From bruce.griffiths at xtra.co.nz Wed Aug 13 21:12:39 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 14 Aug 2008 13:12:39 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A38687.9060100@xtra.co.nz> John Miles wrote: > If you don't want pushbutton convenience, you can measure the close-in phase > noise with not much more than a $5 mixer and $2 opamp. It will take a lot > of "sweat equity," and you will need to build two of whatever you're > measuring, or buy/borrow a known-cleaner source at the same frequency. > > TSC analyzers are great but they are not the only way to go. Actually their > biggest advantages lie in their size/weight and the fact that the reference > doesn't have to be at the same frequency as the DUT. Other than that, their > performance is not necessarily better than a homebrew single-mixer > quadrature PLL or an 11848A. > > -- john, KE5FX > John For compatibility with the PLL technique a trimmer and EFC is required. Using back to back varicaps is supposed to minimise the effect of varicap noise on the oscillator phase noise. The next step below using a cross correlation technique is to use a low phase noise frequency multiplier to decrease the system phase noise floor. A good multiplier can have a significantly lower phase noise floor than a mixer in the flicker phase noise region. Another candidate for evaluation would be an oscillator using a low phase noise modular amplifier with 50 ohm input and output impedance. A splitter is used on the amplifier output to extract a useful signal. Lumped component 1/4 wave lines are used on the input of the modular amplifier and the feedback output of the splitter to achieve a match to Rs/2, where Rs is the crystal series resistance. A full wave diode clamp can be incorporated to limit the crystal dissipation. A phase noise of -156dBc/Hz @100Hz offset has been achieved with such an oscillator. Bruce From cupido at mail.ua.pt Thu Aug 14 06:55:24 2008 From: cupido at mail.ua.pt (Luis Cupido) Date: Thu, 14 Aug 2008 11:55:24 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: References: Message-ID: <48A40F1C.4020800@mail.ua.pt> Related to this, I have a question in my mind for sometime. How close to a decent phase-noise setup are we if we down convert and use a low frequency spectrum analyzer ? (downconverting with the best XTAL LO we can imagine). My target is microwaves and millimeter waves so I have to down convert anyway, Or then I have to live with what my spectrum analyzer show me (a tek 492, in my case). --- Rephrasing the question, how much better are the low frequency spectrum analyzers comparing to the microwave spectrum analysers (in phase noise I mean)? Any comments ? Luis Cupido. ct1dmk. P.S.(I know that I'm limites to 100Hz RBW with my 492... and I would like also to measure closer than that ) John Miles wrote: > If you don't want pushbutton convenience, you can measure the close-in phase > noise with not much more than a $5 mixer and $2 opamp. It will take a lot > of "sweat equity," and you will need to build two of whatever you're > measuring, or buy/borrow a known-cleaner source at the same frequency. > > TSC analyzers are great but they are not the only way to go. Actually their > biggest advantages lie in their size/weight and the fact that the reference > doesn't have to be at the same frequency as the DUT. Other than that, their > performance is not necessarily better than a homebrew single-mixer > quadrature PLL or an 11848A. > > -- john, KE5FX > > >> -----Original Message----- >> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On >> Behalf Of SAIDJACK at aol.com >> Sent: Wednesday, August 13, 2008 4:40 PM >> To: time-nuts at febo.com >> Subject: Re: [time-nuts] Designing and building an OCXO and GPSDO >> >> >> Yup, I agree. >> >> I wish I did have one of those TSC5120A's! >> >> Or "at least" an E5052A/B. >> >> bye, >> Said >> From bruce.griffiths at xtra.co.nz Thu Aug 14 07:40:12 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Thu, 14 Aug 2008 23:40:12 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A40F1C.4020800@mail.ua.pt> References: <48A40F1C.4020800@mail.ua.pt> Message-ID: <48A4199C.5010109@xtra.co.nz> Luis Cupido wrote: > Related to this, I have a question in my mind for sometime. > > How close to a decent phase-noise setup are we if > we down convert and use a low frequency spectrum analyzer ? > (downconverting with the best XTAL LO we can imagine). > > My target is microwaves and millimeter waves so I have to > down convert anyway, Or then I have to live with what my > spectrum analyzer show me (a tek 492, in my case). > > --- > > Rephrasing the question, how much better are the low frequency > spectrum analyzers comparing to the microwave spectrum > analysers (in phase noise I mean)? > > > Any comments ? > > Luis Cupido. > ct1dmk. > > P.S.(I know that I'm limites to 100Hz RBW with my 492... and > I would like also to measure closer than that ) > > Luis The latest spectrum analyser offerings from Agilent have similar phase noise floors for both the millimeter wave and low frequency spectrum analysers. However the low frequency analysers have a lower "flicker" noise corner. The noise floor of a good double balanced mixer is still 30-40dB lower than that a spectrum analyser. Thus you are stuck with using a low bandwidth phase lock loop to get down to the mixer noise floor. Alternatively a dual (first conversion uses analog mixers, 2nd conversion uses DSP techniques) conversion Costas receiver using 4 mixers and 4 ADCs should go down to -170dBc @ offsets of 100Hz or so when correlation techniques are employed. Its a pity the TSC5120A doesnt allow independent access to all 4 of its ADC inputs so a quad of external mixers can be employed to extend the technique to the millimeter wave region. All you need is 4 high resolution ADCs and an offset generator or 2. A couple of high end sound cards may be suitable at least for testing the concepts. Bruce From dougnhelen at moonlink.net Thu Aug 14 13:26:01 2008 From: dougnhelen at moonlink.net (Doug Millar) Date: Thu, 14 Aug 2008 10:26:01 -0700 Subject: [time-nuts] New 10mhz Distribution Amplifier Message-ID: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> Hi, A new 10mhz distribution amplifier is available at amateur prices. Jerry N7EME is producing them. His website is at http://jwmeng.com/model_RDA-6.html Doug K6JEY From bruce.griffiths at xtra.co.nz Thu Aug 14 17:52:29 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 15 Aug 2008 09:52:29 +1200 Subject: [time-nuts] New 10mhz Distribution Amplifier In-Reply-To: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> References: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> Message-ID: <48A4A91D.3050806@xtra.co.nz> Doug Millar wrote: > Hi, > A new 10mhz distribution amplifier is available at amateur prices. > Jerry N7EME is producing them. His website is at > http://jwmeng.com/model_RDA-6.html > Doug K6JEY > > > There's a few specifications missing: 1) input impedance and return loss. 2) output impedance and return loss 3) phase noise These are essential if one is to make a rational decision on the suitability of the distribution amplifier. The outputs and inputs appear to share a common ground. This would preclude its use in some setups without external means of providing the required isolation. The other question is does the device use AGC to set the output level? If it does the phase noise floor will almost inevitably be relatively high compared to the state of the art. Bruce From pe1rks at xs4all.nl Thu Aug 14 18:24:55 2008 From: pe1rks at xs4all.nl (S. Nestra) Date: Fri, 15 Aug 2008 00:24:55 +0200 Subject: [time-nuts] Datum FTS-4040A Cesium standard Message-ID: <48A4B0B7.8050206@xs4all.nl> Hi, I have a problem with a FTS-4040A standard, the LED major fault stays on forever. When I use the monitor program from Symmetricom I see that my OCXO stays cold and I have no Cesium oven voltage. The OCXO does feel warm so this one is warming up, I don't know if the cesium oven is warming up since I can't feel any heat from the CBT. I also don't see any current from the ION pump. After opening the unit I found a burnt resistor R1 on one board, I don't know what it's function is but I would like to know the value of this resistor so I can replace it. So here is my question: does anybody have any technical documentation for this unit and is it possible for someone to lookup this resistor in his standard so I know the value( pictures included for position). I think I have a power supply problem. I welcome all suggestions. Greets, Stijn Nestra Link for the pictures and the list of faults: http://82.95.123.226/fts4040a/ From richard at karlquist.com Thu Aug 14 18:37:11 2008 From: richard at karlquist.com (Rick Karlquist) Date: Thu, 14 Aug 2008 15:37:11 -0700 (PDT) Subject: [time-nuts] New 10mhz Distribution Amplifier In-Reply-To: <48A4A91D.3050806@xtra.co.nz> References: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> <48A4A91D.3050806@xtra.co.nz> Message-ID: <16702.192.25.142.225.1218753431.squirrel@webmail.sonic.net> Additional specs to consider: The return loss should be low for 10 MHz and the first 8 harmonics. The harmonic distortion should be low. The isolation between outputs should be high. The phase drift vs temperature should be low. The short term stability at 1 second should be good. The magnetic field susceptibility should be low. Line sidebands should be low. Compare, for example, the HP5087, a so-so design, to the output amplifier design in the 5071A cesium, as documented in my FCS paper in 1992. Huge difference in specs. The 5071A has 120 dB isolation between outputs. Rick Karlquist N6RK Bruce Griffiths wrote: > Doug Millar wrote: >> Hi, >> A new 10mhz distribution amplifier is available at amateur prices. >> Jerry N7EME is producing them. His website is at >> http://jwmeng.com/model_RDA-6.html >> Doug K6JEY >> >> >> > There's a few specifications missing: > > 1) input impedance and return loss. > > 2) output impedance and return loss > > 3) phase noise > > These are essential if one is to make a rational decision on the > suitability of the distribution amplifier. > > The outputs and inputs appear to share a common ground. > This would preclude its use in some setups without external means of > providing the required isolation. > > The other question is does the device use AGC to set the output level? > If it does the phase noise floor will almost inevitably be relatively > high compared to the state of the art. > > 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 bruce.griffiths at xtra.co.nz Thu Aug 14 18:46:07 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 15 Aug 2008 10:46:07 +1200 Subject: [time-nuts] New 10mhz Distribution Amplifier In-Reply-To: <16702.192.25.142.225.1218753431.squirrel@webmail.sonic.net> References: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> <48A4A91D.3050806@xtra.co.nz> <16702.192.25.142.225.1218753431.squirrel@webmail.sonic.net> Message-ID: <48A4B5AF.4030707@xtra.co.nz> Rick Karlquist wrote: > Additional specs to consider: > > The return loss should be low for 10 MHz and the first 8 harmonics. > The harmonic distortion should be low. > The isolation between outputs should be high. > The phase drift vs temperature should be low. > The short term stability at 1 second should be good. > The magnetic field susceptibility should be low. > Line sidebands should be low. > > Compare, for example, the HP5087, a so-so design, to the > output amplifier design in the 5071A cesium, as documented > in my FCS paper in 1992. Huge difference in specs. The > 5071A has 120 dB isolation between outputs. > > Rick Karlquist N6RK > > > Rick Did you mean a high return loss or equivalently low reflection coefficient? The layout of the board in the picture is perhaps preliminary the input signal track to 3 of the output sections is a little too close to another track. Its hard to tell from the low res image but have thick film resistors been used? These can have excessive flicker noise thus increasing the close in phase noise above that possible with thin film resistors. Bruce From richard at karlquist.com Thu Aug 14 19:13:58 2008 From: richard at karlquist.com (Rick Karlquist) Date: Thu, 14 Aug 2008 16:13:58 -0700 (PDT) Subject: [time-nuts] New 10mhz Distribution Amplifier In-Reply-To: <48A4B5AF.4030707@xtra.co.nz> References: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> <48A4A91D.3050806@xtra.co.nz> <16702.192.25.142.225.1218753431.squirrel@webmail.sonic.net> <48A4B5AF.4030707@xtra.co.nz> Message-ID: <7609.192.25.142.225.1218755638.squirrel@webmail.sonic.net> I should have said the return loss should be "high" or "good" :-) Bruce Griffiths wrote: > Rick Karlquist wrote: >> Additional specs to consider: >> >> The return loss should be low for 10 MHz and the first 8 harmonics. >> The harmonic distortion should be low. >> The isolation between outputs should be high. >> The phase drift vs temperature should be low. >> The short term stability at 1 second should be good. >> The magnetic field susceptibility should be low. >> Line sidebands should be low. >> >> Compare, for example, the HP5087, a so-so design, to the >> output amplifier design in the 5071A cesium, as documented >> in my FCS paper in 1992. Huge difference in specs. The >> 5071A has 120 dB isolation between outputs. >> >> Rick Karlquist N6RK >> >> >> > Rick > > Did you mean a high return loss or equivalently low reflection > coefficient? > > The layout of the board in the picture is perhaps preliminary the input > signal track to 3 of the output sections is a little too close to > another track. > > Its hard to tell from the low res image but have thick film resistors > been used? > These can have excessive flicker noise thus increasing the close in > phase noise above that possible with thin film resistors. > > Bruce > > From rvassar at rob-vassar.com Thu Aug 14 19:24:46 2008 From: rvassar at rob-vassar.com (Robert Vassar) Date: Thu, 14 Aug 2008 18:24:46 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt> <48A2D924.3040809@hvsistemas.es> Message-ID: Good grief! That's not a microcontroller! :-) I like the MCS-51 family, but they're kind of goofy to program in C, and 8-bit. Upside, lots of vendors & variants, including the really nice SiLabs mixed signal chips made here in Austin. AVR is much nicer to code in C, and has great tool support, but they're single source, and I have read that Atmel is not always completely forthcoming in their errata. Arm... If you need something that can run Linux.... But why not just go for a Soekris board at that point? :-) Rob KC6OOM/5 On Aug 13, 2008, at 7:06 PM, Bob Paddock wrote: >> any ARM7 outperforms the best PIC in price and performance :) > > http://beagleboard.org/ > > Get them from DigiKey, $149. > > http://dkc1.digikey.com/us/mkt/beagleboard.html > > "The USB-powered Beagle Board is a low-cost, fan-less single board > > computer utilizing Texas Instruments' OMAP3530 [ARM] application > processor > > that unleashes laptop-like performance and > > expansion without the bulk, expense, or noise of typical desktop > machines. > > Beagle Board is based on an OMAP3530 application processor featuring > an ARM(R) Cortex?-A8 running at up to 600MHz and delivering over 1,200 > Dhrystone MIPS of performance via superscalar operation with highly > accurate branch prediction and 256KB of L2 cache. Focal to Beagle > Board experience is the high-speed USB 2.0 on-the-go (OTG) port that > can be utilized to provide power to the board or to deliver highly > flexible expansion. Standard PC peripherals can be connected to > Beagle Board using the USB with a mini-A to standard-A cable adapter, > DVI-D using an HDMI to DVI-D adapter, or through the MMC/SD/SDIO > connector enabling a complete desktop experience." > > > -- > http://www.wearablesmartsensors.com/ > http://www.softwaresafety.net/ > http://www.designer-iii.com/ > http://www.unusualresearch.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 bruce.griffiths at xtra.co.nz Thu Aug 14 19:44:50 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 15 Aug 2008 11:44:50 +1200 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt> <48A2D924.3040809@hvsistemas.es> Message-ID: <48A4C372.7090104@xtra.co.nz> Robert Vassar wrote: > > Good grief! That's not a microcontroller! :-) > > > > I like the MCS-51 family, but they're kind of goofy to program in C, > and 8-bit. Upside, lots of vendors & variants, including the really > nice SiLabs mixed signal chips made here in Austin. AVR is much > nicer to code in C, and has great tool support, but they're single > source, and I have read that Atmel is not always completely > forthcoming in their errata. > > > Arm... If you need something that can run Linux.... But why not just > go for a Soekris board at that point? :-) > > > Rob > KC6OOM/5 > > You can do substantially better by using a suitable FPGA board. One can create a hardware timestamp counter with multiple capture registers that wont wrap around in less than a week or more together with whatever simple processors required for decoding GPS receiver data. A simple 16 x2 character LCD display or similar is easily added for field readout. Keyboards and pushbuttons together with serial ports USB ports etc are often provided so communications with A PC for data retrieval /storage is readily possible. Bruce From magnus at rubidium.dyndns.org Thu Aug 14 20:17:21 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 15 Aug 2008 02:17:21 +0200 Subject: [time-nuts] New 10mhz Distribution Amplifier In-Reply-To: <7609.192.25.142.225.1218755638.squirrel@webmail.sonic.net> References: <0K5L00L28PRHNVZ4@vms173005.mailsrvcs.net> <48A4A91D.3050806@xtra.co.nz> <16702.192.25.142.225.1218753431.squirrel@webmail.sonic.net> <48A4B5AF.4030707@xtra.co.nz> <7609.192.25.142.225.1218755638.squirrel@webmail.sonic.net> Message-ID: <48A4CB11.3080004@rubidium.dyndns.org> Rick Karlquist wrote: > I should have said the return loss should be "high" or "good" :-) "high" works, "good" depends on the application. :-) I would look at the return loss curve in general. Cheers, Magnus From cupido at mail.ua.pt Thu Aug 14 20:55:13 2008 From: cupido at mail.ua.pt (Luis Cupido) Date: Fri, 15 Aug 2008 01:55:13 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4199C.5010109@xtra.co.nz> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> Message-ID: <48A4D3F1.3050007@mail.ua.pt> Bruce, tks for your reply. > The latest spectrum analyser offerings from Agilent have similar phase > noise floors for both the millimeter wave and low frequency spectrum > analysers. Yes, but kind of puzzles me a bit since I would be expecting phase noises more than 10x worst on a SA covering DC to 1GHz (+/-) (since the LO for this is an YIG oscillator circa 3GHz locked to a reference) comparing with an FFT analyzer that uses a few tens MHz sample rate. Assuming similar 10MHz reference oscillator the SA gets it multiplied by 300 while a low freq SA (preferably FFT) gets it multiplied by 10 maximum. How can they claim similar performance ?! --- Ok on the rest, tks. Luis Cupido. Bruce Griffiths wrote: > Luis > > The latest spectrum analyser offerings from Agilent have similar phase > noise floors for both the millimeter wave and low frequency spectrum > analysers. > However the low frequency analysers have a lower "flicker" noise corner. > > The noise floor of a good double balanced mixer is still 30-40dB lower > than that a spectrum analyser. > > Thus you are stuck with using a low bandwidth phase lock loop to get > down to the mixer noise floor. > > Alternatively a dual (first conversion uses analog mixers, 2nd > conversion uses DSP techniques) conversion Costas receiver using 4 > mixers and 4 ADCs should go down to -170dBc @ offsets of 100Hz or so > when correlation techniques are employed. Its a pity the TSC5120A doesnt > allow independent access to all 4 of its ADC inputs so a quad of > external mixers can be employed to extend the technique to the > millimeter wave region. > > All you need is 4 high resolution ADCs and an offset generator or 2. > A couple of high end sound cards may be suitable at least for testing > the concepts. > > 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 bruce.griffiths at xtra.co.nz Thu Aug 14 21:47:37 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 15 Aug 2008 13:47:37 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4D3F1.3050007@mail.ua.pt> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> <48A4D3F1.3050007@mail.ua.pt> Message-ID: <48A4E039.1070900@xtra.co.nz> Luis Cupido wrote: > Bruce, tks for your reply. > > > The latest spectrum analyser offerings from Agilent have similar phase > > noise floors for both the millimeter wave and low frequency spectrum > > analysers. > > Yes, but kind of puzzles me a bit since I would > be expecting phase noises more than 10x worst on a > SA covering DC to 1GHz (+/-) > (since the LO for this is an YIG oscillator circa 3GHz locked to a > reference) > comparing with an FFT analyzer that uses a few tens MHz sample rate. > > Assuming similar 10MHz reference oscillator the SA > gets it multiplied by 300 while a low freq SA (preferably FFT) > gets it multiplied by 10 maximum. > How can they claim similar performance ?! > --- > > Ok on the rest, tks. > > > Luis Cupido. > > > Luis Perhaps the local oscillator isn't the limiting factor for the low frequency analysers. The claimed noise floor is in the vicinity (within 10dB) of -120dBc/Hz for the analysers for which I checked the specs. If the 10MHz reference has a phase noise floor of around -160dBc/Hz this is only degraded by 50dB or so to -110dBc/Hz when multiplied by 300. The YIG oscillator phase noise floor may perhaps be a little better than this. However, since state of the art ADCs have a phase noise floor of around -150dBc/Hz one would expect a lower phase noise floor from the lower frequency spectrum analysers. Surely there's an FFT based spectrum analyser out there wit this level of performance. Bruce From jmiles at pop.net Thu Aug 14 21:59:25 2008 From: jmiles at pop.net (John Miles) Date: Thu, 14 Aug 2008 18:59:25 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4D3F1.3050007@mail.ua.pt> Message-ID: > Yes, but kind of puzzles me a bit since I would > be expecting phase noises more than 10x worst on a > SA covering DC to 1GHz (+/-) > (since the LO for this is an YIG oscillator circa 3GHz locked to a > reference) > comparing with an FFT analyzer that uses a few tens MHz sample rate. Phase noise is slightly better on the FFT-based analyzers. The RF signal still has to be downconverted to baseband in the FFT analyzers, and they still use YTO synthesizers to do that as far as I'm aware. The difference, with an FFT-based analyzer, is that the synthesizer does not have to be designed with compromises like 1 Hz tuning resolution. It's easier and cheaper to build a clean microwave LO if its tuning resolution is 10 MHz or so. But there are still no free lunches to be had. > Assuming similar 10MHz reference oscillator the SA > gets it multiplied by 300 while a low freq SA (preferably FFT) > gets it multiplied by 10 maximum. > How can they claim similar performance ?! Typically there is an intermediate synthesis stage in the first LO, where the 10 MHz reference is multiplied to a few hundred MHz in a very clean loop. The first LO itself tunes from 2 GHz to (whatever), using a relatively-small 'N' factor. Again this is still true of FFT-based designs; it's just that the 1st LO's intermediate synthesizer can be designed without compromises like noisy subloops or spur-prone DDSs, or a tunable 2nd LO. Looking at figure 1 in the PSA brochure: http://cp.literature.agilent.com/litweb/pdf/5980-1284E.pdf ... it looks like they are still using a high first IF, at 2 GHz or so, because the LO noise profile still looks like a conventional spectrum analyzer. They don't show a second conversion in their PSA series block diagram here: http://cp.literature.agilent.com/litweb/pdf/5980-1283E.pdf (page 15) ... but you can tell it's still there, because there's a 321.4 MHz IF output on the back panel, just like their older analog models. They are either using a traditional multiconversion receiver or an undersampling ADC. My bet would be on the former topology because it still offers the best digitizing performance. -- john, KE5FX From smace at intt.net Thu Aug 14 22:00:46 2008 From: smace at intt.net (Scott Mace) Date: Thu, 14 Aug 2008 21:00:46 -0500 Subject: [time-nuts] thunderbolt for ntpd or gpsd In-Reply-To: <48559045.4080703@stnhbr.com> References: <200806151145.58089.w.knowles@xtra.co.nz> <48559045.4080703@stnhbr.com> Message-ID: <48A4E34E.5080700@intt.net> I found that on the two FatPPS units I have, pin 2 on the female DE-9 connector is tied to the DC-IN. This was causing noise from the thunderbolt RS-232 TX to get into the PPS output. It basically made it totally unusable. I removed R4 since I use DTR for power and it works perfectly. Scott Tim Cwik wrote: > Wayne Knowles wrote: >> Tim, Chris, >> >> Over a month ago I experimented with getting GPSD and the Tunderbolt working >> together. >> I quickly added support for the missing TSIP packet types, and was able to get >> xgps to display lat, long, time and constellation status. I did manage to >> get NTP to work, have not invested the time into getting the 1PPS signal >> working under FreeBSD yet. >> >> I have attached my patches against the gpsd source repository. Note that I >> did not invest much time understanding the internals of gpsd beforehand so >> some aspects may not be fully implemented. >> >> > Thanks Wayne and Chris and Chris. > > I have discovered the even though cgps does not report position or time > using the Thunderbolt, the stock gpsd is getting enough timing data to > update ntp. Gpsd is selected as the sys.peer with a jitter of about .8. > It looks like the PPS pulse is too narrow to be detected on DCD, I am > going to investigate a pulse stretcher available from TAPR > http://tapr.org/kits_fatpps.html and will see if that helps. FWIW, > Centos 5.1 selinux allows gpsd to update the ntp shared memory segment > out of the box. > > > 73, > > > _______________________________________________ > time-nuts mailing list -- 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 Aug 14 22:05:42 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 15 Aug 2008 14:05:42 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4E039.1070900@xtra.co.nz> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> <48A4D3F1.3050007@mail.ua.pt> <48A4E039.1070900@xtra.co.nz> Message-ID: <48A4E476.1060508@xtra.co.nz> Bruce Griffiths wrote: > Luis Cupido wrote: > >> Bruce, tks for your reply. >> >> > The latest spectrum analyser offerings from Agilent have similar phase >> > noise floors for both the millimeter wave and low frequency spectrum >> > analysers. >> >> Yes, but kind of puzzles me a bit since I would >> be expecting phase noises more than 10x worst on a >> SA covering DC to 1GHz (+/-) >> (since the LO for this is an YIG oscillator circa 3GHz locked to a >> reference) >> comparing with an FFT analyzer that uses a few tens MHz sample rate. >> >> Assuming similar 10MHz reference oscillator the SA >> gets it multiplied by 300 while a low freq SA (preferably FFT) >> gets it multiplied by 10 maximum. >> How can they claim similar performance ?! >> --- >> >> Ok on the rest, tks. >> >> >> Luis Cupido. >> >> >> >> Luis The R+S FMU36 has a phase noise floor of around -143dBc/Hz (offset > 10kHz) with a 10MHz input. Whereas the R+S FSU67 has a phase noise floor of around -133dBcdBc/Hz (offset = 10kHz) with a 640Mhz input. There is a definite improvement at lower frequencies but not quite as much as one might have expected. Bruce From jmiles at pop.net Thu Aug 14 22:17:27 2008 From: jmiles at pop.net (John Miles) Date: Thu, 14 Aug 2008 19:17:27 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4E039.1070900@xtra.co.nz> Message-ID: > Perhaps the local oscillator isn't the limiting factor for the low > frequency analysers. > The claimed noise floor is in the vicinity (within 10dB) of -120dBc/Hz > for the analysers for which I checked the specs. > > If the 10MHz reference has a phase noise floor of around -160dBc/Hz > this is only degraded by 50dB or so to -110dBc/Hz when multiplied by 300. > The YIG oscillator phase noise floor may perhaps be a little better than > this. > > However, since state of the art ADCs have a phase noise floor of around > -150dBc/Hz one would expect a lower phase noise floor from the lower > frequency spectrum analysers. > Surely there's an FFT based spectrum analyser out there wit this level > of performance. In the 80s-era analyzers like the 8566, the sampler used in the YTO loop is what hoses you in the end. You can make substantial improvements in the noise performance of both the reference and the intermediate ("M/N") synthesizer, but you hit the sampler's noise floor at around -105 to -110 dBc/Hz. It would be interesting to learn if Agilent's high-end PSA series FFT analyzers still use a sampler-based YTO loop, or if they are now using traditional dividers and phase detectors. Something tells me the service manuals no longer contain schematics and dissertations. :) It is true that 10 MHz @ -160 dBc/Hz * 300 = 3000 MHz @ -110 dBc/Hz, but the devil's in the details. The broadband floor of a 100 MHz reference is no worse than that of a 10 MHz reference, so an obvious optimization is to lock a 100 MHz oscillator to the 10 MHz reference and use *that* as the reference. This gives you more like -130 dBc/Hz in theory. But then you have to tune the reference, so there has to be a synthesizer to drive the final YTO loop. That, assuming you're not limited by sampler/PD noise, is where the majority of the noise comes from. Most synthesizers regardless of technology still end up with broadband floors in the -150 dBc/Hz neighborhood, so now you're back to circa -120 dBc/Hz inband... which is what the PSA-series spec sheets show. It's an interesting business. I spent a lot of time redesigning my 8566B's LO synthesizer, until I realized two things: 1) the YTO sampler noise floor was the real problem, and I didn't feel up to redesigning *that* loop; and 2) lowering the PN floor would probably reveal spurs that the original designers never knew/cared about, which would lead to even more hair-pulling. It would certainly be possible to design a cleaner analyzer LO than the PSA has, but it would cost more, the effort would go unappreciated by most users, and worse, Agilent would sell fewer E5500 outfits! -- john, KE5FX From jmiles at pop.net Thu Aug 14 22:25:22 2008 From: jmiles at pop.net (John Miles) Date: Thu, 14 Aug 2008 19:25:22 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4E476.1060508@xtra.co.nz> Message-ID: > The R+S FMU36 has a phase noise floor of around -143dBc/Hz (offset > > 10kHz) with a 10MHz input. > Whereas the R+S FSU67 has a phase noise floor of around -133dBcdBc/Hz > (offset = 10kHz) with a 640Mhz input. > > There is a definite improvement at lower frequencies but not quite as > much as one might have expected. The *floor* of a YTO loop is not very dependent on the carrier frequency, as the loop bandwidth usually ends up less than 100 kHz. It's more interesting to look at the inband noise at 1 - 10 kHz offsets. The FSU67 looks great in that department: http://www.testbuyer.com/pdf/specs.cfm?pdf_id=56025C0EC7 Looks like it spanks the Agilent by a good 10 dBc/Hz. I want one. :) -- john, KE5FX From jmiles at pop.net Thu Aug 14 22:29:48 2008 From: jmiles at pop.net (John Miles) Date: Thu, 14 Aug 2008 19:29:48 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: Message-ID: > Most synthesizers regardless of technology still end up with broadband > floors in the -150 dBc/Hz neighborhood, so now you're back to circa -120 > dBc/Hz inband... which is what the PSA-series spec sheets show. I didn't phrase that very well; I meant to say that the broadband floor of your phase detector/dividers/other components is what keeps you from being able to drive the final YTO loop at -160 dBc/Hz even though the reference may be even cleaner than that. -- john, KE5FX From didier at cox.net Thu Aug 14 22:51:34 2008 From: didier at cox.net (Didier Juges) Date: Thu, 14 Aug 2008 21:51:34 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> Message-ID: <038e01c8fe81$d4a99920$04000100@didierhp> I am not sure what you mean about the 8051 being goofy to program in C. Aside from the bit variable type, the Special Function Register declarations and the memory types (data, idata and xdata), which you only deal with one time (when declaring variables) and which you can even ignore in many applications (the compiler can take care of it, as long as you are not pushing the limits of the chip's capabilities), the code itself is pure C. The 8051 is considerably easier to program in C than in assembly, and there are several very mature C compilers for the 8051. On the other hand, the ACR being supported by gcc certainly gives it an edge in that area. I use SDCC with the 8051, and it does a very good job. It is actively developped and maintained as a sourceforge project. I routinely compile and run my 8051 C code under gcc on the pc because it's easier to have multiple test cases to make sure the functions do what I think they do... All I need is a few declarations to resolve bit, data, idata and xdata and bingo. Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Vassar > Sent: Thursday, August 14, 2008 6:25 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] I want a good micro-controller > > > > > Good grief! That's not a microcontroller! :-) > > > > I like the MCS-51 family, but they're kind of goofy to > program in C, and 8-bit. Upside, lots of vendors & variants, > including the really nice SiLabs mixed signal chips made here > in Austin. AVR is much nicer to code in C, and has great > tool support, but they're single source, and I have read that > Atmel is not always completely forthcoming in their errata. > > > Arm... If you need something that can run Linux.... But why > not just go for a Soekris board at that point? :-) > > > Rob > KC6OOM/5 > > > On Aug 13, 2008, at 7:06 PM, Bob Paddock wrote: > > >> any ARM7 outperforms the best PIC in price and performance :) > > > > http://beagleboard.org/ > > > > Get them from DigiKey, $149. > > > > http://dkc1.digikey.com/us/mkt/beagleboard.html > > > > "The USB-powered Beagle Board is a low-cost, fan-less single board > > > > computer utilizing Texas Instruments' OMAP3530 [ARM] application > > processor > > > > that unleashes laptop-like performance and > > > > expansion without the bulk, expense, or noise of typical desktop > > machines. > > > > Beagle Board is based on an OMAP3530 application processor > featuring > > an ARM(R) CortexT-A8 running at up to 600MHz and delivering > over 1,200 > > Dhrystone MIPS of performance via superscalar operation with highly > > accurate branch prediction and 256KB of L2 cache. Focal to Beagle > > Board experience is the high-speed USB 2.0 on-the-go (OTG) > port that > > can be utilized to provide power to the board or to deliver highly > > flexible expansion. Standard PC peripherals can be connected to > > Beagle Board using the USB with a mini-A to standard-A > cable adapter, > > DVI-D using an HDMI to DVI-D adapter, or through the MMC/SD/SDIO > > connector enabling a complete desktop experience." > > > > > > -- > > http://www.wearablesmartsensors.com/ > > http://www.softwaresafety.net/ > > http://www.designer-iii.com/ > > http://www.unusualresearch.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. > > > _______________________________________________ > time-nuts mailing list -- 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 w4oa at vibroplex.com Thu Aug 14 23:30:13 2008 From: w4oa at vibroplex.com (F Mitchell) Date: Thu, 14 Aug 2008 22:30:13 -0500 Subject: [time-nuts] Olympic time standard? Message-ID: Is there a common time standard that all of the timed Olympic events are referenced to? I know that Omega provides the timing, their logo is on every computer that you see. If there is a common reference, how is it distributed to all of the events? Mitch From magnus at rubidium.dyndns.org Fri Aug 15 04:39:05 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 15 Aug 2008 10:39:05 +0200 Subject: [time-nuts] Olympic time standard? In-Reply-To: References: Message-ID: <48A540A9.1060204@rubidium.dyndns.org> F Mitchell wrote: > > > Is there a common time standard that all of the timed > > Olympic events are referenced to? I know that Omega > > provides the timing, their logo is on every computer > > that you see. If there is a common reference, how is > > it distributed to all of the events? The Omega site discloses very little detail, rather statistics on how much gear and staff there is. I could hand them a 2.048 MHz on each venue, but I doubt that they would need it. They could have got more timing-oriented time if they would have asked for it, but they haven't. I rather suspect that for most venues they have local clocks and they have TV generators so the clocks of the screen come from there anyway. They mostly need relative timing anyway, so I don't suspect a distribution network. The only distribution they need is the TV pictures and it's there. Cheers, Magnus From martyn at ptsyst.com Fri Aug 15 04:31:18 2008 From: martyn at ptsyst.com (Martyn Smith) Date: Fri, 15 Aug 2008 09:31:18 +0100 Subject: [time-nuts] New 10 MHz Distribution Amplifier In-Reply-To: References: Message-ID: <14E529E1B4BD4A9AB10351EE477743A3@MartynDesktop> I read with interest about the new 10 MHz distribution amplifier. But I agree with everyone, it's the specs that are missing that are important. But I wanted to take one comment up about AGC. My company makes a nice distribution amplifier and we do have AGC. The nice thing here is that a +7 dBm input (e.g PRS10 output) will give you up to +13 dBm output. Despite the AGC we still achieve good phase noise (-135 dBc/Hz @ 1 Hz with a -168 dBc noise floor) together with 130 dB isolation and 10 ps/C phase stability. I suspect this low cost unit has a -140 or -150 dBc noise floor. But our unit costs a lot more than this low cost design, so maybe I'm not being fair in comparing. www.ptsyst.com/DA1-100-10-B.pdf has all our specifications. I could probably talk our sales manager in a once off big discount for time nuts readers, but I suspect it would still be out of the range of amateurs. Send me an email if you are interested (martyn at ptsyst.com) Martyn From martyn at ptsyst.com Fri Aug 15 04:44:58 2008 From: martyn at ptsyst.com (Martyn Smith) Date: Fri, 15 Aug 2008 09:44:58 +0100 Subject: [time-nuts] Importing into EEC In-Reply-To: References: Message-ID: <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> Just wanted to remind everyone it's illegal to import any electronic devices into Europe without them having a CE mark. I see there have been many projects like the Jackson Labs unit that have been imported into Europe. This is illegal. I don't mean to knick pick, but it costs our company about $10000 to CE mark a product. And if we add one small option, it must be CE marked again. To the small manufacturer, this kills us and doesn't allow us to offer low prices. Steve Best Regards Martyn This Email is from: Martyn Smith Precision Test Systems LTD Tel: +44 (0) 1245 329608 Email: martyn at ptsyst.com Web: www.ptsyst.com NOTICE - This message contains legally privileged and confidential information intended only for the use of the addressee named above. If you are not the intended recipient of this message, you are hereby notified that you must not disseminate, distribute, copy or take any action in reliance on it. If you have received this message in error, please notify Precision Test Systems LTD. This communication represents the originator's personal views and opinions, which do not necessarily reflect those of Precision Test Systems Ltd. from whom it emanates. Further, Precision Test Systems Ltd. will not be held responsible for its contents and/or attachments, if the communication contravenes the rules of Precision Test Systems Ltd's email policy. ----- Original Message ----- From: To: Sent: Friday, August 15, 2008 1:17 AM Subject: time-nuts Digest, Vol 49, Issue 32 > 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..." > > > Today's Topics: > > 1. New 10mhz Distribution Amplifier (Doug Millar) > 2. Re: New 10mhz Distribution Amplifier (Bruce Griffiths) > 3. Datum FTS-4040A Cesium standard (S. Nestra) > 4. Re: New 10mhz Distribution Amplifier (Rick Karlquist) > 5. Re: New 10mhz Distribution Amplifier (Bruce Griffiths) > 6. Re: New 10mhz Distribution Amplifier (Rick Karlquist) > 7. Re: I want a good micro-controller (Robert Vassar) > 8. Re: I want a good micro-controller (Bruce Griffiths) > 9. Re: New 10mhz Distribution Amplifier (Magnus Danielson) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 14 Aug 2008 10:26:01 -0700 > From: Doug Millar > Subject: [time-nuts] New 10mhz Distribution Amplifier > To: > Message-ID: <0K5L00L28PRHNVZ4 at vms173005.mailsrvcs.net> > Content-Type: text/plain; charset=us-ascii; format=flowed > > > Hi, > A new 10mhz distribution amplifier is available at amateur prices. > Jerry N7EME is producing them. His website is at > http://jwmeng.com/model_RDA-6.html > Doug K6JEY > > > > > ------------------------------ > > Message: 2 > Date: Fri, 15 Aug 2008 09:52:29 +1200 > From: Bruce Griffiths > Subject: Re: [time-nuts] New 10mhz Distribution Amplifier > To: Discussion of precise time and frequency measurement > > Message-ID: <48A4A91D.3050806 at xtra.co.nz> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Doug Millar wrote: >> Hi, >> A new 10mhz distribution amplifier is available at amateur prices. >> Jerry N7EME is producing them. His website is at >> http://jwmeng.com/model_RDA-6.html >> Doug K6JEY >> >> >> > There's a few specifications missing: > > 1) input impedance and return loss. > > 2) output impedance and return loss > > 3) phase noise > > These are essential if one is to make a rational decision on the > suitability of the distribution amplifier. > > The outputs and inputs appear to share a common ground. > This would preclude its use in some setups without external means of > providing the required isolation. > > The other question is does the device use AGC to set the output level? > If it does the phase noise floor will almost inevitably be relatively > high compared to the state of the art. > > Bruce > > > > ------------------------------ > > Message: 3 > Date: Fri, 15 Aug 2008 00:24:55 +0200 > From: "S. Nestra" > Subject: [time-nuts] Datum FTS-4040A Cesium standard > To: time-nuts at febo.com > Message-ID: <48A4B0B7.8050206 at xs4all.nl> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Hi, > > I have a problem with a FTS-4040A standard, the LED major fault stays on > forever. > When I use the monitor program from Symmetricom I see that my OCXO stays > cold and I have no Cesium oven voltage. The OCXO does feel warm so this > one is warming up, I don't know if the cesium oven is warming up since I > can't feel any heat from the CBT. > I also don't see any current from the ION pump. > After opening the unit I found a burnt resistor R1 on one board, I don't > know what it's function is but I would like to know the value of this > resistor so I can replace it. > So here is my question: does anybody have any technical documentation > for this unit and is it possible for someone to lookup this resistor in > his standard so I know the value( pictures included for position). > I think I have a power supply problem. > I welcome all suggestions. > > Greets, > > Stijn Nestra > > Link for the pictures and the list of > faults: http://82.95.123.226/fts4040a/ > > > > > ------------------------------ > > Message: 4 > Date: Thu, 14 Aug 2008 15:37:11 -0700 (PDT) > From: "Rick Karlquist" > Subject: Re: [time-nuts] New 10mhz Distribution Amplifier > To: "Discussion of precise time and frequency measurement" > > Message-ID: > <16702.192.25.142.225.1218753431.squirrel at webmail.sonic.net> > Content-Type: text/plain;charset=iso-8859-1 > > Additional specs to consider: > > The return loss should be low for 10 MHz and the first 8 harmonics. > The harmonic distortion should be low. > The isolation between outputs should be high. > The phase drift vs temperature should be low. > The short term stability at 1 second should be good. > The magnetic field susceptibility should be low. > Line sidebands should be low. > > Compare, for example, the HP5087, a so-so design, to the > output amplifier design in the 5071A cesium, as documented > in my FCS paper in 1992. Huge difference in specs. The > 5071A has 120 dB isolation between outputs. > > Rick Karlquist N6RK > > > Bruce Griffiths wrote: >> Doug Millar wrote: >>> Hi, >>> A new 10mhz distribution amplifier is available at amateur prices. >>> Jerry N7EME is producing them. His website is at >>> http://jwmeng.com/model_RDA-6.html >>> Doug K6JEY >>> >>> >>> >> There's a few specifications missing: >> >> 1) input impedance and return loss. >> >> 2) output impedance and return loss >> >> 3) phase noise >> >> These are essential if one is to make a rational decision on the >> suitability of the distribution amplifier. >> >> The outputs and inputs appear to share a common ground. >> This would preclude its use in some setups without external means of >> providing the required isolation. >> >> The other question is does the device use AGC to set the output level? >> If it does the phase noise floor will almost inevitably be relatively >> high compared to the state of the art. >> >> 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. >> >> > > > > > > ------------------------------ > > Message: 5 > Date: Fri, 15 Aug 2008 10:46:07 +1200 > From: Bruce Griffiths > Subject: Re: [time-nuts] New 10mhz Distribution Amplifier > To: richard at karlquist.com, Discussion of precise time and frequency > measurement > Message-ID: <48A4B5AF.4030707 at xtra.co.nz> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Rick Karlquist wrote: >> Additional specs to consider: >> >> The return loss should be low for 10 MHz and the first 8 harmonics. >> The harmonic distortion should be low. >> The isolation between outputs should be high. >> The phase drift vs temperature should be low. >> The short term stability at 1 second should be good. >> The magnetic field susceptibility should be low. >> Line sidebands should be low. >> >> Compare, for example, the HP5087, a so-so design, to the >> output amplifier design in the 5071A cesium, as documented >> in my FCS paper in 1992. Huge difference in specs. The >> 5071A has 120 dB isolation between outputs. >> >> Rick Karlquist N6RK >> >> >> > Rick > > Did you mean a high return loss or equivalently low reflection > coefficient? > > The layout of the board in the picture is perhaps preliminary the input > signal track to 3 of the output sections is a little too close to > another track. > > Its hard to tell from the low res image but have thick film resistors > been used? > These can have excessive flicker noise thus increasing the close in > phase noise above that possible with thin film resistors. > > Bruce > > > > ------------------------------ > > Message: 6 > Date: Thu, 14 Aug 2008 16:13:58 -0700 (PDT) > From: "Rick Karlquist" > Subject: Re: [time-nuts] New 10mhz Distribution Amplifier > To: "Bruce Griffiths" > Cc: Discussion of precise time and frequency measurement > > Message-ID: > <7609.192.25.142.225.1218755638.squirrel at webmail.sonic.net> >Content-Type: text/plain;charset=iso-8859-1 > > I should have said the return loss should be "high" or "good" :-) > > Bruce Griffiths wrote: >> Rick Karlquist wrote: >>> Additional specs to consider: >>> >>> The return loss should be low for 10 MHz and the first 8 harmonics. >>> The harmonic distortion should be low. >>> The isolation between outputs should be high. >>> The phase drift vs temperature should be low. >>> The short term stability at 1 second should be good. >>> The magnetic field susceptibility should be low. >>> Line sidebands should be low. >>> >>> Compare, for example, the HP5087, a so-so design, to the >>> output amplifier design in the 5071A cesium, as documented >>> in my FCS paper in 1992. Huge difference in specs. The >>> 5071A has 120 dB isolation between outputs. >>> >>> Rick Karlquist N6RK >>> >>> >>> >> Rick >> >> Did you mean a high return loss or equivalently low reflection >> coefficient? >> >> The layout of the board in the picture is perhaps preliminary the input >> signal track to 3 of the output sections is a little too close to >> another track. >> >> Its hard to tell from the low res image but have thick film resistors >> been used? >> These can have excessive flicker noise thus increasing the close in >> phase noise above that possible with thin film resistors. >> >> Bruce >> >> > > > > > > ------------------------------ > > Message: 7 > Date: Thu, 14 Aug 2008 18:24:46 -0500 > From: Robert Vassar > Subject: Re: [time-nuts] I want a good micro-controller > To: Discussion of precise time and frequency measurement > > Message-ID: > Content-Type: text/plain; charset=WINDOWS-1252; delsp=yes; > format=flowed > > > > > Good grief! That's not a microcontroller! :-) > > > > I like the MCS-51 family, but they're kind of goofy to program in C, > and 8-bit. Upside, lots of vendors & variants, including the really > nice SiLabs mixed signal chips made here in Austin. AVR is much > nicer to code in C, and has great tool support, but they're single > source, and I have read that Atmel is not always completely > forthcoming in their errata. > > > Arm... If you need something that can run Linux.... But why not just > go for a Soekris board at that point? :-) > > > Rob > KC6OOM/5 > > > On Aug 13, 2008, at 7:06 PM, Bob Paddock wrote: > >>> any ARM7 outperforms the best PIC in price and performance :) >> >> http://beagleboard.org/ >> >> Get them from DigiKey, $149. >> >> http://dkc1.digikey.com/us/mkt/beagleboard.html >> >> "The USB-powered Beagle Board is a low-cost, fan-less single board >> >> computer utilizing Texas Instruments' OMAP3530 [ARM] application >> processor >> >> that unleashes laptop-like performance and >> >> expansion without the bulk, expense, or noise of typical desktop >> machines. >> >> Beagle Board is based on an OMAP3530 application processor featuring >> an ARM(R) Cortex?-A8 running at up to 600MHz and delivering over 1,200 >> Dhrystone MIPS of performance via superscalar operation with highly >> accurate branch prediction and 256KB of L2 cache. Focal to Beagle >> Board experience is the high-speed USB 2.0 on-the-go (OTG) port that >> can be utilized to provide power to the board or to deliver highly >> flexible expansion. Standard PC peripherals can be connected to >> Beagle Board using the USB with a mini-A to standard-A cable adapter, >> DVI-D using an HDMI to DVI-D adapter, or through the MMC/SD/SDIO >> connector enabling a complete desktop experience." >> >> >> -- >> http://www.wearablesmartsensors.com/ >> http://www.softwaresafety.net/ >> http://www.designer-iii.com/ >> http://www.unusualresearch.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. > > > > > ------------------------------ > > Message: 8 > Date: Fri, 15 Aug 2008 11:44:50 +1200 > From: Bruce Griffiths > Subject: Re: [time-nuts] I want a good micro-controller > To: Discussion of precise time and frequency measurement > > Message-ID: <48A4C372.7090104 at xtra.co.nz> > Content-Type: text/plain; charset=windows-1252; format=flowed > > Robert Vassar wrote: >> >> Good grief! That's not a microcontroller! :-) >> >> >> >> I like the MCS-51 family, but they're kind of goofy to program in C, >> and 8-bit. Upside, lots of vendors & variants, including the really >> nice SiLabs mixed signal chips made here in Austin. AVR is much >> nicer to code in C, and has great tool support, but they're single >> source, and I have read that Atmel is not always completely >> forthcoming in their errata. >> >> >> Arm... If you need something that can run Linux.... But why not just >> go for a Soekris board at that point? :-) >> >> >> Rob >> KC6OOM/5 >> >> > You can do substantially better by using a suitable FPGA board. > One can create a hardware timestamp counter with multiple capture > registers that wont wrap around in less than a week or more together > with whatever simple processors required for decoding GPS receiver data. > A simple 16 x2 character LCD display or similar is easily added for > field readout. Keyboards and pushbuttons together with serial ports USB > ports etc are often provided so communications with A PC for data > retrieval /storage is readily possible. > > Bruce > > > > ------------------------------ > > Message: 9 > Date: Fri, 15 Aug 2008 02:17:21 +0200 > From: Magnus Danielson > Subject: Re: [time-nuts] New 10mhz Distribution Amplifier > To: richard at karlquist.com, Discussion of precise time and frequency > measurement > Message-ID: <48A4CB11.3080004 at rubidium.dyndns.org> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Rick Karlquist wrote: >> I should have said the return loss should be "high" or "good" :-) > > "high" works, "good" depends on the application. :-) > > I would look at the return loss curve in general. > > Cheers, > Magnus > > > > ------------------------------ > > _______________________________________________ > 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 49, Issue 32 > ***************************************** > From phk at phk.freebsd.dk Fri Aug 15 04:46:26 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 08:46:26 +0000 Subject: [time-nuts] Olympic time standard? In-Reply-To: Your message of "Fri, 15 Aug 2008 10:39:05 +0200." <48A540A9.1060204@rubidium.dyndns.org> Message-ID: <2098.1218789986@critter.freebsd.dk> In message <48A540A9.1060204 at rubidium.dyndns.org>, Magnus Danielson writes: >F Mitchell wrote: >> Is there a common time standard that all of the timed >> Olympic events are referenced to? I belive it is a requirement that there be no external inputs (including power!) to the timing equipment, and therefore I would expect local OCXO's. 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 phk at phk.freebsd.dk Fri Aug 15 04:49:19 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 08:49:19 +0000 Subject: [time-nuts] Importing into EEC In-Reply-To: Your message of "Fri, 15 Aug 2008 09:44:58 +0100." <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> Message-ID: <2121.1218790159@critter.freebsd.dk> In message <63593424D48240B7ADB6FAED64ECD187 at MartynDesktop>, "Martyn Smith" wri tes: >Just wanted to remind everyone it's illegal to import any electronic devices >into Europe without them having a CE mark. That is not true. It is illegal to *sell* things without CE marks to the unwashed public, but you are allowed to import for personal use. In addition there are a vast array of exemptions, including professional test & measurement equipment. Furthermore, anything constructed before the CE mark requirement came into force in their local country are OK. >I see there have been many projects like the Jackson Labs unit that have >been imported into Europe. This is illegal. No, it is not, stop spreading FUD. 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 Aug 15 05:12:55 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 15 Aug 2008 11:12:55 +0200 (CEST) Subject: [time-nuts] Olympic time standard? In-Reply-To: <2098.1218789986@critter.freebsd.dk> References: <2098.1218789986@critter.freebsd.dk> Message-ID: <80838a2edf28da2fb176d5f10273ccd3.squirrel@rubidium.dyndns.org> > In message <48A540A9.1060204 at rubidium.dyndns.org>, Magnus Danielson > writes: >>F Mitchell wrote: > >>> Is there a common time standard that all of the timed >>> Olympic events are referenced to? > > I belive it is a requirement that there be no external inputs > (including power!) to the timing equipment, and therefore I would > expect local OCXO's. Haven't heard about that requirement, but local OCXO's should be good enought. I suspect local power with UPS would be a working deal these days for the power. Cheers, Magnus From rexa at sonic.net Fri Aug 15 05:39:34 2008 From: rexa at sonic.net (Rex) Date: Fri, 15 Aug 2008 02:39:34 -0700 Subject: [time-nuts] Importing into EEC In-Reply-To: <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> References: <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> Message-ID: <48A54ED6.2050602@sonic.net> Martyn Smith wrote: > I don't mean to knick pick, but ... > I assume you didn't mean to nitpick either. Sorry. Not really important. I know it's bad form to criticize grammar on the internet but it caught my attention. Don't get me started on there, their and they're. From df6jb at ulrich-bangert.de Fri Aug 15 05:43:40 2008 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Fri, 15 Aug 2008 11:43:40 +0200 Subject: [time-nuts] New 10mhz Distribution Amplifier In-Reply-To: <16702.192.25.142.225.1218753431.squirrel@webmail.sonic.net> Message-ID: Rick, > Compare, for example, the HP5087, a so-so design, to the > output amplifier design in the 5071A cesium, as documented > in my FCS paper in 1992. Huge difference in specs. The > 5071A has 120 dB isolation between outputs. If I look at your FCS92 paper and specially to figures 5 and 6: Do I understand you correct in the sense that you are proposing a less analogue and more digital styled distribution amplifier with a near-sine construction from an digital clock and analogue output filtering for every output or are you just refering alone to the triangle amplifier building blocks to be seen in figure 5? 73s Ulrich, DF6JB > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von Rick Karlquist > Gesendet: Freitag, 15. August 2008 00:37 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] New 10mhz Distribution Amplifier > > > Additional specs to consider: > > The return loss should be low for 10 MHz and the first 8 > harmonics. The harmonic distortion should be low. The > isolation between outputs should be high. The phase drift vs > temperature should be low. The short term stability at 1 > second should be good. The magnetic field susceptibility > should be low. Line sidebands should be low. > > Compare, for example, the HP5087, a so-so design, to the > output amplifier design in the 5071A cesium, as documented > in my FCS paper in 1992. Huge difference in specs. The > 5071A has 120 dB isolation between outputs. > > Rick Karlquist N6RK > > > Bruce Griffiths wrote: > > Doug Millar wrote: > >> Hi, > >> A new 10mhz distribution amplifier is available at > amateur prices. > >> Jerry N7EME is producing them. His website is at > >> http://jwmeng.com/model_RDA-6.html > >> Doug K6JEY > >> > >> > >> > > There's a few specifications missing: > > > > 1) input impedance and return loss. > > > > 2) output impedance and return loss > > > > 3) phase noise > > > > These are essential if one is to make a rational decision on the > > suitability of the distribution amplifier. > > > > The outputs and inputs appear to share a common ground. > > This would preclude its use in some setups without external > means of > > providing the required isolation. > > > > The other question is does the device use AGC to set the > output level? > > If it does the phase noise floor will almost inevitably be > relatively > > high compared to the state of the art. > > > > 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 BNeubig at t-online.de Fri Aug 15 06:56:07 2008 From: BNeubig at t-online.de (BNeubig at t-online.de) Date: Fri, 15 Aug 2008 12:56:07 +0200 Subject: [time-nuts] =?iso-8859-15?q?New_10_MHz_Distribution_Amplifier?= In-Reply-To: <14E529E1B4BD4A9AB10351EE477743A3@MartynDesktop> References: <14E529E1B4BD4A9AB10351EE477743A3@MartynDesktop> Message-ID: <1KTwyV-21qtnM0@fwd33.aul.t-online.de> Hello Martyn, Martyn Smith wrote: Despite the AGC we still achieve good phase noise (-135 dBc/Hz @ 1 Hz with a -168 dBc noise floor) together with 130 dB isolation and 10 ps/C phase stability. I have problems to understand, how your amplifier can achieve phase noise of -135 dBc/Hz @ 1 Hz. Such a dBc/Hz measure is related to a carrier, but where does the carrier in your amp come from? The same applies to the graph in your data sheet. This obviously shows the phase noise of an oscillator, which feeds your distribution amplifier, not the inherent noise of the amplifier. It needs a different measurement technique to characterize the inherent noise of an amplifier, and there are different numbers to come out of that. At this point I am not able to argue about the -135 dBc/Hz @ 1 Hz for your OCXO, as you do not specify, what model and brand that is. Regards Bernd Neubig DK1AG __________________ AXTAL GmbH & Co.KG www.axtal.com From cupido at mail.ua.pt Fri Aug 15 07:33:47 2008 From: cupido at mail.ua.pt (Luis Cupido) Date: Fri, 15 Aug 2008 12:33:47 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A4E476.1060508@xtra.co.nz> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> <48A4D3F1.3050007@mail.ua.pt> <48A4E039.1070900@xtra.co.nz> <48A4E476.1060508@xtra.co.nz> Message-ID: <48A5699B.4070303@mail.ua.pt> Bruce, John, ... And at smaller offsets like 100Hz and less ? Shouldn't the improvement be even bigger ? Closer to the carrier we are dealing with bigger signals so the ADC issues like resolution should be less important, and the limiting factor should really be the the phase noise of the LO's and etc. Am I right ? Luis Cupido. ct1dmk. Bruce Griffiths wrote: > Luis > > The R+S FMU36 has a phase noise floor of around -143dBc/Hz (offset > > 10kHz) with a 10MHz input. > Whereas the R+S FSU67 has a phase noise floor of around -133dBcdBc/Hz > (offset = 10kHz) with a 640Mhz input. > > There is a definite improvement at lower frequencies but not quite as > much as one might have expected. > > 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 jra at febo.com Fri Aug 15 08:17:40 2008 From: jra at febo.com (John Ackermann N8UR) Date: Fri, 15 Aug 2008 08:17:40 -0400 Subject: [time-nuts] thunderbolt for ntpd or gpsd In-Reply-To: <48A4E34E.5080700@intt.net> References: <200806151145.58089.w.knowles@xtra.co.nz> <48559045.4080703@stnhbr.com> <48A4E34E.5080700@intt.net> Message-ID: <48A573E4.4060101@febo.com> Yes, sadly this was a layout error that didn't get caught until too late (I'm still not sure why the rules check in the board layout software didn't catch it). Removing R4 if you're using DTR for power is the correct answer. John ---- Scott Mace wrote: > I found that on the two FatPPS units I have, pin 2 on the female DE-9 connector > is tied to the DC-IN. This was causing noise from the thunderbolt RS-232 > TX to get into the PPS output. It basically made it totally unusable. > I removed R4 since I use DTR for power and it works perfectly. > > Scott > > Tim Cwik wrote: >> Wayne Knowles wrote: >>> Tim, Chris, >>> >>> Over a month ago I experimented with getting GPSD and the Tunderbolt working >>> together. >>> I quickly added support for the missing TSIP packet types, and was able to get >>> xgps to display lat, long, time and constellation status. I did manage to >>> get NTP to work, have not invested the time into getting the 1PPS signal >>> working under FreeBSD yet. >>> >>> I have attached my patches against the gpsd source repository. Note that I >>> did not invest much time understanding the internals of gpsd beforehand so >>> some aspects may not be fully implemented. >>> >>> >> Thanks Wayne and Chris and Chris. >> >> I have discovered the even though cgps does not report position or time >> using the Thunderbolt, the stock gpsd is getting enough timing data to >> update ntp. Gpsd is selected as the sys.peer with a jitter of about .8. >> It looks like the PPS pulse is too narrow to be detected on DCD, I am >> going to investigate a pulse stretcher available from TAPR >> http://tapr.org/kits_fatpps.html and will see if that helps. FWIW, >> Centos 5.1 selinux allows gpsd to update the ntp shared memory segment >> out of the box. >> >> >> 73, >> >> >> _______________________________________________ >> time-nuts mailing list -- 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 Aug 15 09:03:39 2008 From: jmiles at pop.net (John Miles) Date: Fri, 15 Aug 2008 06:03:39 -0700 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A5699B.4070303@mail.ua.pt> Message-ID: LO phase noise is almost always what limits the noise floor at close-in offsets, because of the narrow RBW (either analog or digital) typically used at those offsets to keep the carrier out of the measurement. Occasionally a high degree of RF attenuation might raise the equivalent front-end noise floor high enough to dominate the LO's inband noise, but that's not usually what happens. Certainly not if you're using a strong carrier to characterize the analyzer's PN floor. Phase noise at 100 Hz would likely be dominated by the reference, either the original 10 MHz reference or a higher-frequency crystal oscillator locked with a very low bandwidth. As in Bruce's example, if the first IF is 2 GHz and the LO is tuned to 3 GHz to receive a 1-GHz signal, there's a 50 dB penalty on a 10 MHz reference (20*log(3000/10)). A decent 10 MHz OCXO is good for about -150 dBc/Hz at 100 Hz from the carrier, so you would expect to see about -100 dBc/Hz at 100 Hz from the carrier on an analyzer built with this sort of architecture. That's a good match for what you see in the PSA data sheet, as well as the FSU67's. The 8560E portables are about 5 dBc/Hz worse. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of Luis Cupido > Sent: Friday, August 15, 2008 4:34 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Designing and building an OCXO and GPSDO > > > Bruce, > John, > .... > > And at smaller offsets like 100Hz and less ? > Shouldn't the improvement be even bigger ? > Closer to the carrier we are dealing with bigger signals > so the ADC issues like resolution should be less important, > and the limiting factor should really be the the > phase noise of the LO's and etc. > Am I right ? > > > Luis Cupido. > ct1dmk. > > > > Bruce Griffiths wrote: > > > Luis > > > > The R+S FMU36 has a phase noise floor of around -143dBc/Hz (offset > > > 10kHz) with a 10MHz input. > > Whereas the R+S FSU67 has a phase noise floor of around -133dBcdBc/Hz > > (offset = 10kHz) with a 640Mhz input. > > > > There is a definite improvement at lower frequencies but not quite as > > much as one might have expected. > > > > 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 bruce.griffiths at xtra.co.nz Fri Aug 15 09:28:44 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 16 Aug 2008 01:28:44 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A5699B.4070303@mail.ua.pt> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> <48A4D3F1.3050007@mail.ua.pt> <48A4E039.1070900@xtra.co.nz> <48A4E476.1060508@xtra.co.nz> <48A5699B.4070303@mail.ua.pt> Message-ID: <48A5848C.80901@xtra.co.nz> Luis Cupido wrote: > Bruce, > John, > ... > > And at smaller offsets like 100Hz and less ? > Shouldn't the improvement be even bigger ? > Closer to the carrier we are dealing with bigger signals > so the ADC issues like resolution should be less important, > and the limiting factor should really be the the > phase noise of the LO's and etc. > Am I right ? > > > Luis Cupido. > ct1dmk. > Luis The R&S FSU67 has a phase noise of around -104dBc/Hz at 100Hz offset with a 640MHz input The R&S FMU36 has phase noise of around -115dBc/Hz at 100Hz offset with a 10MHz input. The limiting factor at low offsets is almost certainly due to local oscillator phase noise. Bruce From bruce.griffiths at xtra.co.nz Fri Aug 15 09:35:19 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 16 Aug 2008 01:35:19 +1200 Subject: [time-nuts] New 10 MHz Distribution Amplifier In-Reply-To: <14E529E1B4BD4A9AB10351EE477743A3@MartynDesktop> References: <14E529E1B4BD4A9AB10351EE477743A3@MartynDesktop> Message-ID: <48A58617.3050604@xtra.co.nz> Martyn Smith wrote: > I read with interest about the new 10 MHz distribution amplifier. > > But I agree with everyone, it's the specs that are missing that are > important. > > But I wanted to take one comment up about AGC. > > It depends how the AGC is done, there are some really poor examples for sale. > My company makes a nice distribution amplifier and we do have AGC. The nice > thing here is that a +7 dBm input (e.g PRS10 output) will give you up to +13 > dBm output. > > Despite the AGC we still achieve good phase noise (-135 dBc/Hz @ 1 Hz with > a -168 dBc noise floor) together with 130 dB isolation and 10 ps/C phase > stability. > > The phase noise at 1Hz offset is about 15dB or so higher than the state of the art. The effect of AGC should be most noticeable at low offsets. A phase tempco of 10ps/C is a bit for high precision work. > I suspect this low cost unit has a -140 or -150 dBc noise floor. > > But our unit costs a lot more than this low cost design, so maybe I'm not > being fair in comparing. > > www.ptsyst.com/DA1-100-10-B.pdf has all our specifications. > > I could probably talk our sales manager in a once off big discount for time > nuts readers, but I suspect it would still be out of the range of amateurs. > > Send me an email if you are interested (martyn at ptsyst.com) > > Martyn > Bruce From jim77742 at gmail.com Fri Aug 15 09:46:43 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Fri, 15 Aug 2008 23:46:43 +1000 Subject: [time-nuts] Importing into EEC In-Reply-To: <48A54ED6.2050602@sonic.net> References: <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> <48A54ED6.2050602@sonic.net> Message-ID: My pet hate is loose and lose. And there are many sufferers on this forum too... But no names! :-) Jim 2008/8/15 Rex > Martyn Smith wrote: > > I don't mean to knick pick, but ... > > > > I assume you didn't mean to nitpick either. > > Sorry. Not really important. I know it's bad form to criticize grammar > on the internet but it caught my attention. Don't get me started on > there, their and they're. > > > > _______________________________________________ > time-nuts mailing list -- 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 martyn at ptsyst.com Fri Aug 15 10:12:56 2008 From: martyn at ptsyst.com (Martyn Smith) Date: Fri, 15 Aug 2008 15:12:56 +0100 Subject: [time-nuts] CE Mark In-Reply-To: References: Message-ID: Sorry you are wrong. There is no exemtion for CE marking. Nothing is excempt. All test equipment, all electronic equipment, even "toothpaste" must be CE marked. There is no exemtion for personal use. You maybe are getting confused with RoHS where test equipment is exempt. Martyn From martyn at ptsyst.com Fri Aug 15 10:21:26 2008 From: martyn at ptsyst.com (Martyn Smith) Date: Fri, 15 Aug 2008 15:21:26 +0100 Subject: [time-nuts] Distribution Amplifier Phase Noise In-Reply-To: References: Message-ID: <9DAB23E903A947EA9F7F995879BC680B@MartynDesktop> Bernd, We in fact often make -140 dBc @ 1 Hz. However, our plots are of the amplifier only, not of any reference oscillator used. The measurement technique we use cancels out the inherent phase noise of the source used. The measurement technique takes a 10 MHz oscillator, splits it into two legs, phase shift one leg 90 degrees (quadature) and then measures the phase noise of the two legs. The phase noise of the source is cancelled out in this measurement technique. But remember, you do get oscillators that make -130 dBc/Hz at 1 Hz. Obviously it is essential for any distribution amplifier to be lower than the reference used. 10 dB is really the minimum margin that is needed. This can be very hard to achieve at times. We can achieve a floor noise of -172 dBc/Hz if we work hard at it. Regards Martyn From martyn at ptsyst.com Fri Aug 15 10:28:13 2008 From: martyn at ptsyst.com (Martyn Smith) Date: Fri, 15 Aug 2008 15:28:13 +0100 Subject: [time-nuts] Spellimng Mistakes In-Reply-To: References: Message-ID: Hi All, Yes I can't spell. I've just realised my spell checker isn't working. Not only can't I spell, I can't type!!! I did mean exemption if my previous email. Best Regards Martyn Best Regards From dave.g0dja at tiscali.co.uk Fri Aug 15 10:37:51 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Fri, 15 Aug 2008 15:37:51 +0100 Subject: [time-nuts] Importing into EEC In-Reply-To: References: <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> <48A54ED6.2050602@sonic.net> Message-ID: <48A594BF.7060008@tiscali.co.uk> Jim Palfreyman wrote: > My pet hate is loose and lose. > Perhaps we could form a chapter of the AAAA? http://www.worldwidewords.org/articles/apostrophe.htm Dave (G0DJA) From rk at timing-consultants.com Fri Aug 15 11:45:24 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Fri, 15 Aug 2008 16:45:24 +0100 Subject: [time-nuts] Importing into EEC In-Reply-To: <2121.1218790159@critter.freebsd.dk> References: Your message of "Fri, 15 Aug 2008 09:44:58 +0100."<63593424D48240B7ADB6FAED64ECD187@MartynDesktop> <2121.1218790159@critter.freebsd.dk> Message-ID: <37C195870F1247CA91138B8A0326521E@Robin> It depends on local interpretations of the CE rules. UK as usual in all things emanating from the EU does it all to the letter, so yes, it is illegal here (may be a bit more relaxed up your way Poul, as common sense and EU don't seem to mix down here!). One can get exceptions in a few cases, especially if military customers are involved. But, the general rule is that if it hasn't got a CE mark in the UK you can't sell it. Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Poul-Henning Kamp Sent: 15 August 2008 09:49 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Importing into EEC In message <63593424D48240B7ADB6FAED64ECD187 at MartynDesktop>, "Martyn Smith" wri tes: >Just wanted to remind everyone it's illegal to import any electronic >devices into Europe without them having a CE mark. That is not true. It is illegal to *sell* things without CE marks to the unwashed public, but you are allowed to import for personal use. In addition there are a vast array of exemptions, including professional test & measurement equipment. Furthermore, anything constructed before the CE mark requirement came into force in their local country are OK. >I see there have been many projects like the Jackson Labs unit that >have been imported into Europe. This is illegal. No, it is not, stop spreading FUD. 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 rexa at sonic.net Fri Aug 15 11:59:40 2008 From: rexa at sonic.net (Rex) Date: Fri, 15 Aug 2008 08:59:40 -0700 Subject: [time-nuts] Importing into EEC In-Reply-To: <48A594BF.7060008@tiscali.co.uk> References: <63593424D48240B7ADB6FAED64ECD187@MartynDesktop> <48A54ED6.2050602@sonic.net> <48A594BF.7060008@tiscali.co.uk> Message-ID: <48A5A7EC.1070803@sonic.net> Avian branch of the Apostrophe Police: http://www.xertech.net/pub/puncbird2.jpg -Rex David Ackrill wrote: > Jim Palfreyman wrote: > >> My pet hate is loose and lose. >> >> > > Perhaps we could form a chapter of the AAAA? > > http://www.worldwidewords.org/articles/apostrophe.htm > > Dave (G0DJA) > > _______________________________________________ > time-nuts mailing list -- 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 Fri Aug 15 12:16:34 2008 From: SAIDJACK at aol.com (SAIDJACK at aol.com) Date: Fri, 15 Aug 2008 12:16:34 EDT Subject: [time-nuts] CE Mark Message-ID: Hello Martyn, please keep in mind that CE marking is a self-certified mark. Not like the FCC marking, that has to be "officially" tested and certified by a big lab. I am sure a lot of products from Asia just have a label affixed to them, and never underwent any real testing. Also, most of the Jackson Labs products underwent CE testing and certification by several of our European resellers, and are so marked when sold under their private label, so they are electrically CE compliant. Bye, Said In a message dated 8/15/2008 07:14:01 Pacific Daylight Time, martyn at ptsyst.com writes: Sorry you are wrong. There is no exemtion for CE marking. Nothing is excempt. All test equipment, all electronic equipment, even "toothpaste" must be CE marked. There is no exemtion for personal use. You maybe are getting confused with RoHS where test equipment is exempt. Martyn **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-Volkswagen-Jetta-2009/expert-review?ncid=aolaut00030000000007 ) From mark.amos at toast.net Fri Aug 15 13:07:36 2008 From: mark.amos at toast.net (Mark Amos) Date: Fri, 15 Aug 2008 13:07:36 -0400 Subject: [time-nuts] Frequency distribution amp in Europe Message-ID: I'm not expert, but I suspect that this additional cost for electronic equipment could be one of the major contributing reasons that the time in some European countries can be up to 6 or even 8 hours off compared to "standard" North American time (EST.) I'm just sayin... Mark Message: 4 Date: Fri, 15 Aug 2008 09:44:58 +0100 From: "Martyn Smith" Subject: [time-nuts] Importing into EEC To: Message-ID: <63593424D48240B7ADB6FAED64ECD187 at MartynDesktop> Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Just wanted to remind everyone it's illegal to import any electronic devices into Europe without them having a CE mark. I see there have been many projects like the Jackson Labs unit that have been imported into Europe. This is illegal. I don't mean to knick pick, but it costs our company about $10000 to CE mark a product. And if we add one small option, it must be CE marked again. To the small manufacturer, this kills us and doesn't allow us to offer low prices. Steve Best Regards Martyn This Email is from: Martyn Smith Precision Test Systems LTD Tel: +44 (0) 1245 329608 Email: martyn at ptsyst.com Web: www.ptsyst.com NOTICE - This message contains legally privileged and confidential information intended only for the use of the addressee named above. If you are not the intended recipient of this message, you are hereby notified that you must not disseminate, distribute, copy or take any action in reliance on it. If you have received this message in error, please notify Precision Test Systems LTD. This communication represents the originator's personal views and opinions, which do not necessarily reflect those of Precision Test Systems Ltd. from whom it emanates. Further, Precision Test Systems Ltd. will not be held responsible for its contents and/or attachments, if the communication contravenes the rules of Precision Test Systems Ltd's email policy. From rk at timing-consultants.com Fri Aug 15 13:10:51 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Fri, 15 Aug 2008 18:10:51 +0100 Subject: [time-nuts] CE Mark In-Reply-To: References: Message-ID: CE testing/marking is a mine field. Not as simple a statement as self certifying! You need to tie in the CE certification with declarations of conformity (safety, EMC etc etc), all of which need testing. It's an expensive business. Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of SAIDJACK at aol.com Sent: 15 August 2008 17:17 To: time-nuts at febo.com Subject: Re: [time-nuts] CE Mark Hello Martyn, please keep in mind that CE marking is a self-certified mark. Not like the FCC marking, that has to be "officially" tested and certified by a big lab. I am sure a lot of products from Asia just have a label affixed to them, and never underwent any real testing. Also, most of the Jackson Labs products underwent CE testing and certification by several of our European resellers, and are so marked when sold under their private label, so they are electrically CE compliant. Bye, Said In a message dated 8/15/2008 07:14:01 Pacific Daylight Time, martyn at ptsyst.com writes: Sorry you are wrong. There is no exemtion for CE marking. Nothing is excempt. All test equipment, all electronic equipment, even "toothpaste" must be CE marked. There is no exemtion for personal use. You maybe are getting confused with RoHS where test equipment is exempt. Martyn **************Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-Volkswagen-Jetta-2009/expert-review?ncid=aolaut00 030000000007 ) _______________________________________________ time-nuts mailing list -- 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 Fri Aug 15 14:12:16 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 18:12:16 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 15:12:56 +0100." Message-ID: <1635.1218823936@critter.freebsd.dk> In message , "Martyn Smith" wri tes: >Sorry you are wrong. > >There is no exemtion for CE marking. Nothing is excempt. All test >equipment, all electronic equipment, even "toothpaste" must be CE marked. The CE rules only cover retail sale, it does not cover personal imports from non-CE countries, that would have been against WTO rules and caused an instant trade-war with both asia and USA. -- 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 Fri Aug 15 14:14:53 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 18:14:53 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 18:10:51 +0100." Message-ID: <1689.1218824093@critter.freebsd.dk> In message , "Rob Kimberley" writes: >CE testing/marking is a mine field. Not as simple a statement as self >certifying! You need to tie in the CE certification with declarations of >conformity (safety, EMC etc etc), all of which need testing. No, you only need to tie them to measurements if you don't want to personally shoulder the blame if they are found to be non-conforming. -- 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 Arnold.Tibus at gmx.de Fri Aug 15 15:53:56 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Fri, 15 Aug 2008 21:53:56 +0200 Subject: [time-nuts] CE Mark In-Reply-To: Message-ID: Hi to all, indeed, the CE-marking is quite complicated and sometimes a 'pain in the neck', but obviously necessary as well. I believe that all industrial manufactured products are affected, but I am not anymore in touch with these regulations. I found some pages with explanations and extracted some sentences for rough info, see yourself: from the European Parliament: http://www.europarl.europa.eu/news/expert/infopress_page/063-21952-049-02-08-911-20080221IPR21949-18-02-2008-2008-true/default_en.htm CE marking means a marking which materializes the declaration of the manufacturer that the product is in conformity with the applicable requirements set out in Community harmonization legislation providing for its affixing" says the committee in the agreement with the Council. Burden on importers In the agreement with the Council, the European Parliament underlines that importers must place only compliant products on the Community market. Before placing a product on the market importers must ensure that the appropriate conformity assessment procedure has been carried out by the manufacturer. They must ensure that the manufacturer has drawn up the technical documentation, that the product bears the required conformity marking(s), is accompanied by the required documents and that the manufacturer has respected the requirements set out in the directive. ... http://www.ce-marking.org/what-product.html Does my product need CE Marking? ... CE Marking is most probably required if you export to the 27 European Union (EU) and 3 European Free Trade Association (EFTA) member states the following 20 groups of products 3. # Low Voltage Electrical Equipment The "Electrical Equipment" means any equipment designed for use with a voltage rating of between 50 and 1000 V for alternating current (A.C.) and between 75 and 1500 V for direct current (D.C.). Therefore, it is called often "Low Voltage Electrical Equipment" which includes the vast majority of electrical equipment in everyday use. more >> 10. Measuring Instruments the "measuring instrument" means: any device or system with a measurement function that is covered by Articles 1 and 3; 15. Radio Equipment & Telecommunications Terminal Equipment (R&TTE) A "radio equipment" means a product, or relevant component thereof, capable of communication by means of the emission and/or reception of radio waves utilising the spectrum allocated to terrestrial/space radiocommunication. etc. http://www.ce-marking.org/93465eec+conformity+assessment+procedures+ce+marking+rules.html Annex, I. GENERAL GUIDELINES A. The principal guidelines for the use of conformity assessment procedures in technical harmonization directives are the following: (a) the essential objective of a conformity assessment procedure is to enable the public authorities to ensure that products placed on the market conform to the requirements as expressed in the provisions of the directives, in particular with regard to the health and safety of users and consumers; B. (b) The CE marking affixed to industrial products symbolizes the fact that the natural or legal person having affixed or been responsible for the affixing of the said marking has verified that the product conforms to all the Community total harmonization provisions which apply to it and has been the subject of the appropriate conformity evaluation procedures. 4. The CE marking must be affixed visibly, legibly and indelibly. (e) Any industrial product covered by the technical harmonization directives based on the principles of the global approach must bear the CE marking, save where the specific directives provide otherwise; such exceptions constitute derogations not from the marking requirement but from the administrative procedures for conformity evaluation, which may in certain cases be considered too cumbersome. Appropriate grounds must accordingly be given for any exception to or derogation from the marking requirement. The CE marking is the only marking which certifies that the industrial products conform to the directives based on the principles of the global approach. So far the not complete excerpts, good luck! Arnold, DK2WT ++++++++++++++++++++++++++++++++++++++++++++++++++++++ On Fri, 15 Aug 2008 18:10:51 +0100, Rob Kimberley wrote: >CE testing/marking is a mine field. Not as simple a statement as self >certifying! You need to tie in the CE certification with declarations of >conformity (safety, EMC etc etc), all of which need testing. >It's an expensive business. >Rob Kimberley >-----Original Message----- >From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On >Behalf Of SAIDJACK at aol.com >Sent: 15 August 2008 17:17 >To: time-nuts at febo.com >Subject: Re: [time-nuts] CE Mark >Hello Martyn, > >please keep in mind that CE marking is a self-certified mark. Not like the >FCC marking, that has to be "officially" tested and certified by a big lab. >I am sure a lot of products from Asia just have a label affixed to them, >and never underwent any real testing. > >Also, most of the Jackson Labs products underwent CE testing and >certification by several of our European resellers, and are so marked when >sold under their private label, so they are electrically CE compliant. > >Bye, >Said > > >In a message dated 8/15/2008 07:14:01 Pacific Daylight Time, >martyn at ptsyst.com writes: >Sorry you are wrong. >There is no exemtion for CE marking. Nothing is excempt. All test >equipment, all electronic equipment, even "toothpaste" must be CE marked. >There is no exemtion for personal use. >You maybe are getting confused with RoHS where test equipment is exempt. >Martyn >**************Looking for a car that's sporty, fun and fits in your budget? >Read reviews on AOL Autos. >(http://autos.aol.com/cars-Volkswagen-Jetta-2009/expert-review?ncid=aolaut00 >030000000007 ) _______________________________________________ >time-nuts mailing list -- 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 Fri Aug 15 16:06:21 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 20:06:21 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 21:53:56 +0200." Message-ID: <2356.1218830781@critter.freebsd.dk> In message , "Arnold Tibus" writes: >I found some pages with explanations and extracted some sentences for rough >info, see yourself: And you caught the most important part: >Burden on importers > >In the agreement with the Council, the European Parliament underlines >that importers must place only compliant products on the Community >market. Before placing a product on the market importers must ensure >that [...] The important thing in this clause is "placing a product on the market". As long as you import things directly into EU, and never sell them again, there is no requirement for CE marking. 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 Arnold.Tibus at gmx.de Fri Aug 15 16:10:03 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Fri, 15 Aug 2008 22:10:03 +0200 Subject: [time-nuts] CE Mark In-Reply-To: <1689.1218824093@critter.freebsd.dk> Message-ID: A summary somewhat easier to read you can find here: CE Marking: Your Passport to the European Union http://www.i-b-t.net/anm/templates/trade_article.asp?articleid=262&zoneid=3 perhaps it can bring some more light into the darkness of the worldtrade and the european market. regards Arnold, DK2WT From dforbes at dakotacom.net Fri Aug 15 16:10:52 2008 From: dforbes at dakotacom.net (David Forbes) Date: Fri, 15 Aug 2008 13:10:52 -0700 Subject: [time-nuts] CE Mark In-Reply-To: <2356.1218830781@critter.freebsd.dk> References: <2356.1218830781@critter.freebsd.dk> Message-ID: <48A5E2CC.9020602@dakotacom.net> Poul-Henning Kamp wrote: >> >> In the agreement with the Council, the European Parliament underlines >> that importers must place only compliant products on the Community >> market. Before placing a product on the market importers must ensure >> that [...] > > The important thing in this clause is "placing a product on the market". > > As long as you import things directly into EU, and never sell them > again, there is no requirement for CE marking. > Poul, This is interesting. It means that I, as an American exporter selling directly to end customers in the EU, do NOT need to CE mark my American made products. -- David Forbes, Tucson AZ, Estados Unidos Americanos From phk at phk.freebsd.dk Fri Aug 15 16:20:11 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 20:20:11 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 13:10:52 MST." <48A5E2CC.9020602@dakotacom.net> Message-ID: <2688.1218831611@critter.freebsd.dk> In message <48A5E2CC.9020602 at dakotacom.net>, David Forbes writes: >Poul-Henning Kamp wrote: >>> >>> In the agreement with the Council, the European Parliament underlines >>> that importers must place only compliant products on the Community >>> market. Before placing a product on the market importers must ensure >>> that [...] >> >> The important thing in this clause is "placing a product on the market". >> >> As long as you import things directly into EU, and never sell them >> again, there is no requirement for CE marking. >> > >Poul, > >This is interesting. It means that I, as an American exporter selling directly >to end customers in the EU, do NOT need to CE mark my American made products. Correct, provided if you don't otherwise end up "placing the product on the market", ie: by advertising directly in the EU or in global media targeting EU audiences (ie: in native language). -- 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 dave.g0dja at tiscali.co.uk Fri Aug 15 16:32:50 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Fri, 15 Aug 2008 21:32:50 +0100 Subject: [time-nuts] CE Mark In-Reply-To: <48A5E2CC.9020602@dakotacom.net> References: <2356.1218830781@critter.freebsd.dk> <48A5E2CC.9020602@dakotacom.net> Message-ID: <48A5E7F2.50708@tiscali.co.uk> David Forbes wrote: > This is interesting. It means that I, as an American exporter selling directly > to end customers in the EU, do NOT need to CE mark my American made products. > I have bought several items from the US for personal use, and not for resale, I don't remember any of them having a CE mark and no one stopped me doing this. Now, this might be because the trade for persoan imports of small electronic items is not worth bothering about, or it could be that there's no legal obligation on me to ensure that what I buy has a CE mark... I also have a couple of Amateur bands handheld radios, bought second hand in the UK, that are from China and widely available to import through eBay. However, the UK Government is always keen to make sure I pay the various taxes levied on my purchases, so they must know that it is happening. Dave (G0DJA) From phk at phk.freebsd.dk Fri Aug 15 16:34:36 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 20:34:36 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 22:10:03 +0200." Message-ID: <2770.1218832476@critter.freebsd.dk> In message , "Arnold Tibus" writes: >A summary somewhat easier to read you can find here: > >CE Marking: Your Passport to the European Union >http://www.i-b-t.net/anm/templates/trade_article.asp?articleid=262&zoneid=3 > >perhaps it can bring some more light into the darkness of the >worldtrade and the european market. HA! It doesn't even scratch the surface. First of all, that article incorporates, tacitly, US corporate legal liability thinking. Mostly, there are only two steps in the generic CE process: Sign a piece of paper that says that you put the CE mark there. Put the CE mark there. If your product does not live up to CE requirement, you have just made yourself the bulls-eye of the lawsuit or regulatory action. Obviously, anybody in a sane frame of mind would check that the requirements are met before doing that, but the law doesn't demand that you do so, it just assigns the liability. In select areas, where the danger to life and limb is greater than normal, cars, airbags and similar, there is a positive documentation requirement. As far as I know, no plain electrical gadget is under that regime, until voltages above 500V are exposed or radio transmission is involved. Once you get beyond electrical gadgets, it gets weirder. Take building materials: if they are CE marked, they can be sold anywhere in the EU, but that doesn't mean that you are actually allowed to build with them where you live. A window that complies with building codes in Greece fail northern energy-concious building codes. What Denmark consider a sound structual wall material would crumble in the first minor tremblor in Greece. You buy insulation materials from the northern end, and fumigate your house in the southern end ? You'd better not plan on moving back into the house because it will take years for the poison gas to be released again. They're talking about putting CE marks on foodstuffs also, but that is even more fraught with peril, because the "sell before date" is climate variant on a lot of foodstuffs. 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 dave.g0dja at tiscali.co.uk Fri Aug 15 16:38:21 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Fri, 15 Aug 2008 21:38:21 +0100 Subject: [time-nuts] CE Mark In-Reply-To: <2688.1218831611@critter.freebsd.dk> References: <2688.1218831611@critter.freebsd.dk> Message-ID: <48A5E93D.5030606@tiscali.co.uk> Poul-Henning Kamp wrote: > Correct, provided if you don't otherwise end up "placing the product > on the market", ie: by advertising directly in the EU or in global > media targeting EU audiences (ie: in native language). > That's interesting, given that it is often said that the UK and the US are two countries separated by a common language. What about if a non-EU company sponsors a website, hosted in Europe, and has their logo and products shown on the website, must their products be CE marked even if the end users import the units from the non-EU supplier? If so, that could impact on a lot of Amateur Radio, and other specialist interest, forums... Dave (G0DJA) From Arnold.Tibus at gmx.de Fri Aug 15 16:38:55 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Fri, 15 Aug 2008 22:38:55 +0200 Subject: [time-nuts] CE Mark In-Reply-To: <2356.1218830781@critter.freebsd.dk> Message-ID: Poul-Henning, you are propably fully right! >And you caught the most important part: >>Burden on importers >> >>In the agreement with the Council, the European Parliament underlines >>that importers must place only compliant products on the Community >>market. Before placing a product on the market importers must ensure >>that [...] >The important thing in this clause is "placing a product on the market". >As long as you import things directly into EU, and never sell them >again, there is no requirement for CE marking. >Poul-Henning when reading this: [...] "For the purpose of law  all importers are treated as producers. (Ref article 3 council directive (85/374/EEC) [!!!] This is the reason that Importers in Europe are so much worried about CE Marking on the product they import because one failure of product in the market can ruin earnings of many years. " To safeguard their interest the importer needs CE marking from a notified body.Without CE Mark- complainant is awarded the damage and manufacturer is liable without limit. With CE Mark- the injured person shall be required to prove the damage, the defect and the causal relationship between defect and damage "[...] If I do import and not sell to others, I should have no problems, I am responsible for - myself (!), I am as importer the 'producer' (a.m.) for my own needs if I see it right. Nobody will ask (in case of single items or very small quantities for my own needs), but I may have problems to claim for something in case of trouble when the product is not safe... [...) "CONCLUSION: It is the sole responsibility of the Manufacturer/ Seller to identify the applicable Directives[...] http://ce-marking.blogspot.com/2008/07/your-liability-when-you-ce-mark-your.html regards, Arnold, DK2WT From phk at phk.freebsd.dk Fri Aug 15 16:51:10 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 20:51:10 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 22:38:55 +0200." Message-ID: <2952.1218833470@critter.freebsd.dk> In message , "Arnold Tibus" writes: >Poul-Henning, >[...] "For the purpose of law all importers are treated as >producers. (Ref article 3 council directive (85/374/EEC) [!!!] > >This is the reason that Importers in Europe are so much worried >about CE Marking on the product they import because one failure of >product in the market can ruin earnings of many years. The point here is to get a local entity to sue, rather than some random chinese factory which have never existed once the mail arrives. Rumours have it, that the CE mark went through like lightning after a delegation from the EP/PE was taken through a Wall-Mart in the USA, and subsequently shown what the products contained and how they were constructed. I have not been able to verify this rumour. If you don't sell crap, you've got nothing to worry about. >If I do import and not sell to others, I should have no problems, I am >responsible for - myself (!), Exactly, as a group europeans are not known for suing themselves :-) But you could be held liable if your neighbor, child or spouse gets electrocuted, although they would probably use penal code rather than lack of CE mark in that case. 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 phk at phk.freebsd.dk Fri Aug 15 16:57:18 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Fri, 15 Aug 2008 20:57:18 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Fri, 15 Aug 2008 21:38:21 +0100." <48A5E93D.5030606@tiscali.co.uk> Message-ID: <2982.1218833838@critter.freebsd.dk> In message <48A5E93D.5030606 at tiscali.co.uk>, David Ackrill writes: >Poul-Henning Kamp wrote: >> Correct, provided if you don't otherwise end up "placing the product >> on the market", ie: by advertising directly in the EU or in global >> media targeting EU audiences (ie: in native language). > >That's interesting, given that it is often said that the UK and the US >are two countries separated by a common language. I can warmly recommend "The midatlantic companion" by David Frost. >What about if a non-EU company sponsors a website, hosted in Europe, and >has their logo and products shown on the website, must their products be >CE marked even if the end users import the units from the non-EU supplier? Well, this is where you get to ask yourself if your lawyers are better than their laywers. As long as your product cannot kill anybody, the amount of liability you can have if you just slap a CE mark onto your product is limited, and that's all the testing what a lot of battery/low-voltage products go through. >If so, that could impact on a lot of Amateur Radio, and other specialist >interest, forums... I doubt it, proving that something is _not_ CE compliant is a pretty expensive process, and you can't sue somebody without evidence of wrongdoing. Just "supecting it is not CE compliant" will get you thrown out of a european court with a fine. So before anybody gets in trouble, somebody has to get hurt enough that tests are carried out. Most of the enforcement cases I have heard about have been form jealous competitors, which as I read it, also started this thread. 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 dibene at usa.net Fri Aug 15 16:59:19 2008 From: dibene at usa.net (Alberto di Bene) Date: Fri, 15 Aug 2008 22:59:19 +0200 Subject: [time-nuts] CE Mark In-Reply-To: References: Message-ID: <48A5EE27.6070503@usa.net> And beware from the CE Mark on goods coming from China.... What it does mean is just "China Export", and I am not kidding... 73 Alberto I2PHD From holrum at hotmail.com Fri Aug 15 17:06:34 2008 From: holrum at hotmail.com (Mark Sims) Date: Fri, 15 Aug 2008 21:06:34 +0000 Subject: [time-nuts] FTS-4060M/S24 finally says LOCKed In-Reply-To: References: Message-ID: Well, after a couple of months of continuous operation my 4060M cesium beam unit, it finally decided to say that it was LOCKed. It had been operating happily, but never said it was LOCKed. It appeared that the auto-ALIGN subroutine in the EPROM was corrupted because it would never do the control voltage sweep to find the correct resonance peak. It would turn of the MOD signal, then just sit there. You could align the unit manually and it was obviously locked (tracked GPSDO to within a few nanoseconds/day). Today, I walked in and found the green LOCK led had lit up. I checked all the monitor voltages and found that my quartz oven monitor level was now 3.6V like the manual says it should be. Previously it showed 5.0V (which I attributed to the fact that the OCXO was a FTS unit and not the usual Datum unit). I wonder what made it decide to start showing the proper OCXO oven monitor level? ---------------------------------------- _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From bruce.griffiths at xtra.co.nz Fri Aug 15 17:07:58 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 16 Aug 2008 09:07:58 +1200 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A5699B.4070303@mail.ua.pt> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> <48A4D3F1.3050007@mail.ua.pt> <48A4E039.1070900@xtra.co.nz> <48A4E476.1060508@xtra.co.nz> <48A5699B.4070303@mail.ua.pt> Message-ID: <48A5F02E.9090902@xtra.co.nz> Luis Cupido wrote: > Bruce, > John, > ... > > And at smaller offsets like 100Hz and less ? > Shouldn't the improvement be even bigger ? > Closer to the carrier we are dealing with bigger signals > so the ADC issues like resolution should be less important, > and the limiting factor should really be the the > phase noise of the LO's and etc. > Am I right ? > > > Luis Cupido. > ct1dmk. > > > > Luis The R&S FMU 36 is a baseband analyser employing a pair of 80MSPS ADCs so only the preamp, ADC, and 80MHz oscillator phase noise should be significant (assuming the calculation roundoff noise isnt a factor). Bruce From Arnold.Tibus at gmx.de Fri Aug 15 17:12:50 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Fri, 15 Aug 2008 23:12:50 +0200 Subject: [time-nuts] CE Mark In-Reply-To: <2952.1218833470@critter.freebsd.dk> Message-ID: On Fri, 15 Aug 2008 20:51:10 +0000, Poul-Henning Kamp wrote: >But you could be held liable if your neighbor, child or spouse gets >electrocuted, although they would probably use penal code rather >than lack of CE mark in that case. >Poul-Henning I am thinking exactly the same, perhaps this point was not expressed clear enough. I am always responsible affecting others somehow . Therefore specially radio amateurs have to pay attention when importing industrial manufactured rf-devices, radios etc. Because the 'long arm' of em-waves, neighbours and others are always somehow affected. That is why the EMC-regulations are more strict and without any 'humor', they must be fulfilled and what must be demonstrated in this case always by the producer/ importer! Therefore all products eg. from the well known transceiver manufacturer in Asia must have passed the necessary tests and show the CE mark as I am informed. regards Arnold, DK2WT From holrum at hotmail.com Fri Aug 15 17:36:18 2008 From: holrum at hotmail.com (Mark Sims) Date: Fri, 15 Aug 2008 21:36:18 +0000 Subject: [time-nuts] LPRO-101 internals In-Reply-To: References: Message-ID: Recently one of my LPRO-101 rubidium oscillators start acting flakey. First it started to not lock if it was powered up hot (like if switched off for a few seconds then switched back on). Next it started dropping out of lock while running. I replaced it with one of those $100 units from China (60 bucks if you by them by the bucket) which works just fine. So I decided to open up the flakey one and see if there was anything tweakable inside... well there is another pot, two variable caps, three variable inductors, and two select-to-test resistors. Oh yeah, not to mention 21 (yep, count 'em... 21) different two-pin jumper headers. And an 8 pin header mounted so it is accessible from the outisde world. And two other internal conenctor headers. Does anybody out there know what any of these goodies do? Does anybody know what tweakage might bring the flakey unit back to life if it starts acting up again? It saw that I was going to outsource its job to a cheap Chinese import and started working properly... ---------------------------------------- _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 From rvassar at rob-vassar.com Fri Aug 15 20:08:26 2008 From: rvassar at rob-vassar.com (Robert Vassar) Date: Fri, 15 Aug 2008 19:08:26 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <038e01c8fe81$d4a99920$04000100@didierhp> References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> <038e01c8fe81$d4a99920$04000100@didierhp> Message-ID: Didier, "Goofy" is certainly an inappropriate engineering term. As I see it, the MCS-51 is ill suited to programming with a C compiler because of the small stack size and segmented RAM map. This makes writing an efficient code generator more difficult, and you have to keep certain limitations in mind while coding. These things don't make it impossible though, and I agree it's easier with SDCC than in pure ASM. Keil C is the benchmark by which all others are judged, but it costs several hundred $USD. The AVR has a nice flat memory map, plenty of registers, etc... It's just easier to write a compiler for. That isn't necessarily a benefit, as most of us are never going to write a compiler. The PIC... I have no nice words for the PIC. It's a CPU architecture kept alive by Donald Rumsfeld himself (He was the CEO of G.I. back in the '70's), and surely he must have made a deal with the Devil to make it as successful as it is. How's that for a religious argument? :-) Having said all that... Looking thru my parts box, I have ~20 MCS-51 variants, ranging from the original i80C31 that I learned on back in the mid-80's to a couple 89C450's and a AT89C51ED2 in 40 pdip that I wish I had a few more of. I have a couple Z80's, an 8085, 68000, 68020, none of which are particularly useful anymore. Then there's that one lone 16F84 PIC and it's programmer, which I think I used once. Cheers, Rob KC6OOM/5 On Aug 14, 2008, at 9:51 PM, Didier Juges wrote: > I am not sure what you mean about the 8051 being goofy to program > in C. > > Aside from the bit variable type, the Special Function Register > declarations > and the memory types (data, idata and xdata), which you only deal > with one > time (when declaring variables) and which you can even ignore in many > applications (the compiler can take care of it, as long as you are not > pushing the limits of the chip's capabilities), the code itself is > pure C. > > The 8051 is considerably easier to program in C than in assembly, > and there > are several very mature C compilers for the 8051. On the other > hand, the ACR > being supported by gcc certainly gives it an edge in that area. I > use SDCC > with the 8051, and it does a very good job. It is actively > developped and > maintained as a sourceforge project. > > I routinely compile and run my 8051 C code under gcc on the pc > because it's > easier to have multiple test cases to make sure the functions do > what I > think they do... All I need is a few declarations to resolve bit, > data, > idata and xdata and bingo. > > Didier KO4BB > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Vassar >> Sent: Thursday, August 14, 2008 6:25 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] I want a good micro-controller >> >> >> >> >> Good grief! That's not a microcontroller! :-) >> >> >> >> I like the MCS-51 family, but they're kind of goofy to >> program in C, and 8-bit. Upside, lots of vendors & variants, >> including the really nice SiLabs mixed signal chips made here >> in Austin. AVR is much nicer to code in C, and has great >> tool support, but they're single source, and I have read that >> Atmel is not always completely forthcoming in their errata. >> >> >> Arm... If you need something that can run Linux.... But why >> not just go for a Soekris board at that point? :-) >> >> >> Rob >> KC6OOM/5 >> >> >> On Aug 13, 2008, at 7:06 PM, Bob Paddock wrote: >> >>>> any ARM7 outperforms the best PIC in price and performance :) >>> >>> http://beagleboard.org/ >>> >>> Get them from DigiKey, $149. >>> >>> http://dkc1.digikey.com/us/mkt/beagleboard.html >>> >>> "The USB-powered Beagle Board is a low-cost, fan-less single board >>> >>> computer utilizing Texas Instruments' OMAP3530 [ARM] application >>> processor >>> >>> that unleashes laptop-like performance and >>> >>> expansion without the bulk, expense, or noise of typical desktop >>> machines. >>> >>> Beagle Board is based on an OMAP3530 application processor >> featuring >>> an ARM(R) CortexT-A8 running at up to 600MHz and delivering >> over 1,200 >>> Dhrystone MIPS of performance via superscalar operation with highly >>> accurate branch prediction and 256KB of L2 cache. Focal to Beagle >>> Board experience is the high-speed USB 2.0 on-the-go (OTG) >> port that >>> can be utilized to provide power to the board or to deliver highly >>> flexible expansion. Standard PC peripherals can be connected to >>> Beagle Board using the USB with a mini-A to standard-A >> cable adapter, >>> DVI-D using an HDMI to DVI-D adapter, or through the MMC/SD/SDIO >>> connector enabling a complete desktop experience." >>> >>> >>> -- >>> http://www.wearablesmartsensors.com/ >>> http://www.softwaresafety.net/ >>> http://www.designer-iii.com/ >>> http://www.unusualresearch.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. >> >> >> _______________________________________________ >> time-nuts mailing list -- 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 didier at cox.net Fri Aug 15 21:30:25 2008 From: didier at cox.net (Didier Juges) Date: Fri, 15 Aug 2008 20:30:25 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: <48A2BEC0.50004@quackers.net><48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es><038e01c8fe81$d4a99920$04000100@didierhp> Message-ID: <004601c8ff3f$a92fbe00$0a01a8c0@didierhp> Rob, I have been using the Keil compiler for work and home for about 15 years and only recently started using SDCC for home. They both do a fine job, even though SDCC still goes through some growing pains. I agree that having to keep track of data, idata and xdata is not a desirable feature by any stretch of the imagination, but with a little bit of discipline (and experience certainly does not hurt) you know what's critical and what's not, and unless you are trying to get the last microounce of performance or you are using a very small device, use the large memory model and fuget about it :-) Of course, if you take C code written for the PC (or for a multitasking OS) and try to run it as is on an 8051, you will quickly get out of stack and other resources, but no responsible coder would do that. One could argue that the lack of code migration to a 16 or 32 bit platform hurt the architecture, but it's only since we have started to put an ethernet interface and a TCP/IP stack that we have come close to the 64k limit (without code banking, which I would rather not have to do). I am debating at the moment if my next TCP/IP project will use the 8051 or if we will go to a 32 bit chip directly, and if so, the field is wide open. Code performance has not been an issue for me, and I suspect that with the 100 MIPs of the Silabs C8051F120, I won't get close to the limit any time soon. I started on the 8051 with the 87C552 15 years ago, but recently I kinda standardized on the Silabs familly. They have a good range, with excellent performance, good tools and good support, so at the moment (aside from the TCP/IP applications) I have no plan to switch. 73, Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Vassar > Sent: Friday, August 15, 2008 7:08 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] I want a good micro-controller > > Didier, > > > "Goofy" is certainly an inappropriate engineering term. As I > see it, the MCS-51 is ill suited to programming with a C > compiler because of the small stack size and segmented RAM > map. This makes writing an efficient code generator more > difficult, and you have to keep certain limitations in mind > while coding. These things don't make it impossible though, > and I agree it's easier with SDCC than in pure ASM. Keil C > is the benchmark by which all others are judged, but it costs > several hundred $USD. > > The AVR has a nice flat memory map, plenty of registers, > etc... It's just easier to write a compiler for. That isn't > necessarily a benefit, as most of us are never going to write > a compiler. > > > The PIC... I have no nice words for the PIC. It's a CPU > architecture kept alive by Donald Rumsfeld himself (He was > the CEO of G.I. back in the '70's), and surely he must have > made a deal with the Devil to make it as successful as it is. > How's that for a religious argument? :-) > > > Having said all that... Looking thru my parts box, I have ~20 > MCS-51 variants, ranging from the original i80C31 that I > learned on back in the mid-80's to a couple 89C450's and a > AT89C51ED2 in 40 pdip that I wish I had a few more of. I > have a couple Z80's, an 8085, 68000, 68020, none of which are > particularly useful anymore. Then there's that one lone > 16F84 PIC and it's programmer, which I think I used once. > > > Cheers, > > Rob > KC6OOM/5 > > > On Aug 14, 2008, at 9:51 PM, Didier Juges wrote: > > > I am not sure what you mean about the 8051 being goofy to > program in > > C. > > > > Aside from the bit variable type, the Special Function Register > > declarations and the memory types (data, idata and xdata), > which you > > only deal with one time (when declaring variables) and > which you can > > even ignore in many applications (the compiler can take > care of it, as > > long as you are not pushing the limits of the chip's capabilities), > > the code itself is pure C. > > > > The 8051 is considerably easier to program in C than in > assembly, and > > there are several very mature C compilers for the 8051. On > the other > > hand, the ACR being supported by gcc certainly gives it an edge in > > that area. I use SDCC with the 8051, and it does a very > good job. It > > is actively developped and maintained as a sourceforge project. > > > > I routinely compile and run my 8051 C code under gcc on the > pc because > > it's easier to have multiple test cases to make sure the > functions do > > what I think they do... All I need is a few declarations to resolve > > bit, data, idata and xdata and bingo. > > > > Didier KO4BB > > > >> -----Original Message----- > >> From: time-nuts-bounces at febo.com > >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Robert Vassar > >> Sent: Thursday, August 14, 2008 6:25 PM > >> To: Discussion of precise time and frequency measurement > >> Subject: Re: [time-nuts] I want a good micro-controller > >> > >> > >> > >> > >> Good grief! That's not a microcontroller! :-) > >> > >> > >> > >> I like the MCS-51 family, but they're kind of goofy to > program in C, > >> and 8-bit. Upside, lots of vendors & variants, including > the really > >> nice SiLabs mixed signal chips made here in Austin. AVR is much > >> nicer to code in C, and has great tool support, but they're single > >> source, and I have read that Atmel is not always completely > >> forthcoming in their errata. > >> > >> > >> Arm... If you need something that can run Linux.... But > why not just > >> go for a Soekris board at that point? :-) > >> > >> > >> Rob > >> KC6OOM/5 > >> > >> > >> On Aug 13, 2008, at 7:06 PM, Bob Paddock wrote: > >> > >>>> any ARM7 outperforms the best PIC in price and performance :) > >>> > >>> http://beagleboard.org/ > >>> > >>> Get them from DigiKey, $149. > >>> > >>> http://dkc1.digikey.com/us/mkt/beagleboard.html > >>> > >>> "The USB-powered Beagle Board is a low-cost, fan-less single board > >>> > >>> computer utilizing Texas Instruments' OMAP3530 [ARM] application > >>> processor > >>> > >>> that unleashes laptop-like performance and > >>> > >>> expansion without the bulk, expense, or noise of typical desktop > >>> machines. > >>> > >>> Beagle Board is based on an OMAP3530 application processor > >> featuring > >>> an ARM(R) CortexT-A8 running at up to 600MHz and delivering > >> over 1,200 > >>> Dhrystone MIPS of performance via superscalar operation > with highly > >>> accurate branch prediction and 256KB of L2 cache. Focal > to Beagle > >>> Board experience is the high-speed USB 2.0 on-the-go (OTG) > >> port that > >>> can be utilized to provide power to the board or to > deliver highly > >>> flexible expansion. Standard PC peripherals can be connected to > >>> Beagle Board using the USB with a mini-A to standard-A > >> cable adapter, > >>> DVI-D using an HDMI to DVI-D adapter, or through the MMC/SD/SDIO > >>> connector enabling a complete desktop experience." > >>> > >>> > >>> -- > >>> http://www.wearablesmartsensors.com/ > >>> http://www.softwaresafety.net/ > >>> http://www.designer-iii.com/ > >>> http://www.unusualresearch.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. > >> > >> > >> _______________________________________________ > >> time-nuts mailing list -- 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 Aug 15 22:12:40 2008 From: cfharris at erols.com (Chuck Harris) Date: Fri, 15 Aug 2008 22:12:40 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> <038e01c8fe81$d4a99920$04000100@didierhp> Message-ID: <48A63798.50908@erols.com> Robert Vassar wrote: > > > The PIC... I have no nice words for the PIC. It's a CPU architecture > kept alive by Donald Rumsfeld himself (He was the CEO of G.I. back in > the '70's), and surely he must have made a deal with the Devil to > make it as successful as it is. How's that for a religious > argument? :-) > > > Having said all that... Looking thru my parts box, I have ~20 MCS-51 > variants, ranging from the original i80C31 that I learned on back in > the mid-80's to a couple 89C450's and a AT89C51ED2 in 40 pdip that I > wish I had a few more of. I have a couple Z80's, an 8085, 68000, > 68020, none of which are particularly useful anymore. Then there's > that one lone 16F84 PIC and it's programmer, which I think I used once. Oh good, they we can take your opinion on PIC's as that of an expert. -Chuck Harris From GandalfG8 at aol.com Sat Aug 16 06:28:58 2008 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sat, 16 Aug 2008 06:28:58 EDT Subject: [time-nuts] I want a good micro-controller Message-ID: In a message dated 16/08/2008 01:11:09 GMT Daylight Time, rvassar at rob-vassar.com writes: The PIC... I have no nice words for the PIC. It's a CPU architecture kept alive by Donald Rumsfeld himself (He was the CEO of G.I. back in the '70's), and surely he must have made a deal with the Devil to make it as successful as it is. How's that for a religious argument? :-) ------------- LOL Keeping it secular, what's with the PIC bashing? Surely it's a case of horses for courses, and there's been enough successful commercial, as well as hobby, products based on PICs to suggest you might be just a wee bit out of touch with some parts of the real world:-) regards Nigel GM8PZR From iovane at inwind.it Sat Aug 16 07:15:08 2008 From: iovane at inwind.it (iovane at inwind.it) Date: Sat, 16 Aug 2008 13:15:08 +0200 Subject: [time-nuts] LPRO-101 internals Message-ID: I suggest not touching any of the adjustment points. Check the rb light. If it gets too reddish, then probably the lamp gets too hot. There is a resistor in the heater circuitry that may be faulty. I'm away at the moment, and don't have my notes on hand, but the resistor is on the bottom side of the board and has a value of 61900 Ohm (6192). Good luck. Antonio I8IOV > > Recently one of my LPRO-101 rubidium oscillators start acting flakey. First it started to not lock if it was powered up hot (like if switched off for a few seconds then switched back on). Next it started dropping out of lock while running. I replaced it with one of those $100 units from China (60 bucks if you by them by the bucket) which works just fine. > > So I decided to open up the flakey one and see if there was anything tweakable inside... well there is another pot, two variable caps, three variable inductors, and two select-to-test resistors. Oh yeah, not to mention 21 (yep, count 'em... 21) different two-pin jumper headers. And an 8 pin header mounted so it is accessible from the outisde world. And two other internal conenctor headers. > > Does anybody out there know what any of these goodies do? Does anybody know what tweakage might bring the flakey unit back to life if it starts acting up again? It saw that I was going to outsource its job to a cheap Chinese import and started working properly... > ---------------------------------------- > > _________________________________________________________________ > See what people are saying about Windows Live. Check out featured posts. > http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 > _______________________________________________ > time-nuts mailing list -- 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 Aug 16 07:55:26 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 16 Aug 2008 13:55:26 +0200 Subject: [time-nuts] CE Mark In-Reply-To: <48A5E7F2.50708@tiscali.co.uk> References: <2356.1218830781@critter.freebsd.dk> <48A5E2CC.9020602@dakotacom.net> <48A5E7F2.50708@tiscali.co.uk> Message-ID: <48A6C02E.6000406@rubidium.dyndns.org> David Ackrill wrote: > David Forbes wrote: > >> This is interesting. It means that I, as an American exporter selling directly >> to end customers in the EU, do NOT need to CE mark my American made products. >> > > I have bought several items from the US for personal use, and not for > resale, I don't remember any of them having a CE mark and no one stopped > me doing this. > > Now, this might be because the trade for persoan imports of small > electronic items is not worth bothering about, or it could be that > there's no legal obligation on me to ensure that what I buy has a CE mark... > > I also have a couple of Amateur bands handheld radios, bought second > hand in the UK, that are from China and widely available to import > through eBay. > > However, the UK Government is always keen to make sure I pay the various > taxes levied on my purchases, so they must know that it is happening. The thing is, when you buy a non CE-marked product and things get out of hand. Like electrical safety or apparent violation of EMC rules or something, you and not the manufacture takes the blame. So you are interested in it even as a buyer. If it is reasnoble to assume it would conform, the risc is lower. For radio equipment, it needs to conform to the ETSI ENs as applicable, which are part of a CE mark. There has also surfaced a missconception about the testing aspect. For some equpment testing is required before putting the product on the market. For most others it is a thing which is wise to do before putting the product on the market. You really need to check the details for each product. For most of the equipment we discuss here, it is not required, but if you don't have it you don't know if you comply and you can be in big trouble, such as pulling the product of the market and stuff like that. Cheers, Magnus From magnus at rubidium.dyndns.org Sat Aug 16 08:02:49 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 16 Aug 2008 14:02:49 +0200 Subject: [time-nuts] CE Mark In-Reply-To: <48A5E93D.5030606@tiscali.co.uk> References: <2688.1218831611@critter.freebsd.dk> <48A5E93D.5030606@tiscali.co.uk> Message-ID: <48A6C1E9.70706@rubidium.dyndns.org> David Ackrill wrote: > Poul-Henning Kamp wrote: > >> Correct, provided if you don't otherwise end up "placing the product >> on the market", ie: by advertising directly in the EU or in global >> media targeting EU audiences (ie: in native language). >> > > That's interesting, given that it is often said that the UK and the US > are two countries separated by a common language. > > What about if a non-EU company sponsors a website, hosted in Europe, and > has their logo and products shown on the website, must their products be > CE marked even if the end users import the units from the non-EU supplier? > > If so, that could impact on a lot of Amateur Radio, and other specialist > interest, forums... It's part of marketing to EU customers, so... they are certainly in for CE marketing. Infact, one of their competitors could get them caugt in serious pain. So, yes. Cheers, Magnus From wje at quackers.net Sat Aug 16 08:36:05 2008 From: wje at quackers.net (wje) Date: Sat, 16 Aug 2008 08:36:05 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: <48A6C9B5.8040607@quackers.net> As the one who made the first comment about not liking the PIC, I'll give you my reasons. Yes, they are philosophical, even religious. I'm also distinguishing between microprocessors (this discussion) and other variants, such as DSPs, FPLDs, etc. First, I've used a very large number of different micros over the years for both 'real' work and my own purposes, starting with the Intel 8008 before it was commercially released. I've used Intel, TI, Motorola, Zilog, MOS Tech processors of multiple families, and yes, even PICs, all with wildly varying architectures. These days, given modern development tools, the architecture of a general-purpose micro really isn't particularly relevant. It's functionality and support tools that are important. Without a doubt, PIC made it possible for many hobbyists to put together nice projects that they would not necessarily have been able to do otherwise. My deep-seated revulsion comes from one source, and it's not the architecture, the company, or the capabilities of the chips. It's Basic, the language. Until relatively recently, PIC and Basic were almost synonymous, at least for the masses. I have both EE and CS degrees, and I work in both worlds. In my humble (but completely accurate and stable) opinion, Basic is not a programming language. It's a tool of Satan designed to convince people that they are programmers when they really should stick to their janitorial duties. This is a subset of the general problem that everyone thinks they are programmers, and usually think their code is perfect. But, that's a rant for a different audience. So, for me, given that there are some very good C development tools for mainstream processors, and frequently they are free, I just don't use PICs. As I mentioned earlier, I currently like the Motorola (I mean, Freescale; these silly name changes are yet another rant) MC68HCxx line; there's a wide choice of features and they can be flashed easily without a complicated programmer. The 8-pin xx908QT4 is a buck and does a fine job for many purposes, and most importantly, you can get a nice C development environment for the line, which was originally from CodeWarrior, for free. It also supports the entire line, from 8-bit to 32-bit, and with builtin support for all of the various on-chip 'peripherals'. Even now, I don't think Microchip provides a compiler that supports the low-end chips, but I haven't checked lately. But, when you get right down to it, you really need to pick the proper solution for your problem. If there was something the PICs provided that I couldn't get elsewhere, I'd use them. Religion is fine, but getting the job done is more important. BTW, for those that think you can't do anything with an 8-pin 8-bit micro, I did one design that supports an LCD, a rotary encoder, a Hall-effect sensor, and a button. At home, I use the same chip in every light switch in my house to implement a self-tuning capacitance sense switch. I even use a couple for a more time-nuts related tasks. One provides loop control for my GPS/Rb/Quartz standard, and one is used as a 555 timer replacement in my SmartClock->PC interface. (Ok, I was in a hurry, needed a pulse stretcher, and I didn't have any 555's lying around) Bill Ezell ---------- They said 'Windows or better' so I used Linux. GandalfG8 at aol.com wrote: > > In a message dated 16/08/2008 01:11:09 GMT Daylight Time, > rvassar at rob-vassar.com writes: > > The PIC... I have no nice words for the PIC. It's a CPU architecture > kept alive by Donald Rumsfeld himself (He was the CEO of G.I. back in > the '70's), and surely he must have made a deal with the Devil to > make it as successful as it is. How's that for a religious > argument? :-) > > > ------------- > LOL > > Keeping it secular, what's with the PIC bashing? > > Surely it's a case of horses for courses, and there's been enough successful > commercial, as well as hobby, products based on PICs to suggest you might be > just a wee bit out of touch with some parts of the real world:-) > > 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 rvassar at rob-vassar.com Sat Aug 16 09:44:50 2008 From: rvassar at rob-vassar.com (Robert Vassar) Date: Sat, 16 Aug 2008 08:44:50 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: <72894FB3-2532-4596-B050-869E8B872E41@rob-vassar.com> On Aug 16, 2008, at 5:28 AM, GandalfG8 at aol.com wrote: > > > Keeping it secular, what's with the PIC bashing? > > Surely it's a case of horses for courses, and there's been enough > successful > commercial, as well as hobby, products based on PICs to suggest > you might be > just a wee bit out of touch with some parts of the real world:-) > > regards > > Nigel > GM8PZR > > And: > Oh good, they we can take your opinion on PIC's as that of an expert. > > -Chuck Harris > Gentlemen, I could not have made that more tongue-in-cheek! It's a good thing this isn't about Python, the Amiga, or the obvious superiority of "vi", or I would have seen some real flames! My opinion on PIC's is no more valid than my opinion on brands of car. I can make some observations drawn from 20+ years of computing/ electronics hobby, and 15 years as a software professional. But I am not a professional embedded systems engineer. I can have entirely valid, well thought out reasons, but at the end of the day it's not much different than "I like VW, and I don't like Dodge". I can go fetch groceries with either one. To a professional, perhaps nothing of interest. To someone contemplating buying one of the "PIC'n" books or building any kind of programmer that involves two 9 volt batteries, perhaps they will find my comments a useful warning. As a member of the "brain damaged by Basic" generation, I mostly agree with Bill's comments regarding it's use. Yet I still keep the public domain 8052AH-BASIC image in my '51 code directory, and have fond memories of it's use. The PIC is not alone in propagating that mistake, though they seem to be the last. Cheers, Rob From jim77742 at gmail.com Sat Aug 16 10:03:44 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Sun, 17 Aug 2008 00:03:44 +1000 Subject: [time-nuts] CE Mark In-Reply-To: <48A6C1E9.70706@rubidium.dyndns.org> References: <2688.1218831611@critter.freebsd.dk> <48A5E93D.5030606@tiscali.co.uk> <48A6C1E9.70706@rubidium.dyndns.org> Message-ID: Geez folks, You've all been caught by a Troll. What's this really got to do with time??? Someone in all the above said an importer is a producer. A producer can produce. It's when they sell, things get interesting. Likewise an importer can import. It's when they sell, things get interesting. As time-nuts with a weird hobby we can import or produce. It's when we sell, things get interesting. End of story. For those of you who are professionals and selling your product, I'm sure you've spoken to your lawyer. Can we drop it now? Please. The troll is laughing at us. Jim 2008/8/16 Magnus Danielson > David Ackrill wrote: > > Poul-Henning Kamp wrote: > > > >> Correct, provided if you don't otherwise end up "placing the product > >> on the market", ie: by advertising directly in the EU or in global > >> media targeting EU audiences (ie: in native language). > >> > > > > That's interesting, given that it is often said that the UK and the US > > are two countries separated by a common language. > > > > What about if a non-EU company sponsors a website, hosted in Europe, and > > has their logo and products shown on the website, must their products be > > CE marked even if the end users import the units from the non-EU > supplier? > > > > If so, that could impact on a lot of Amateur Radio, and other specialist > > interest, forums... > > It's part of marketing to EU customers, so... they are certainly in for > CE marketing. Infact, one of their competitors could get them caugt in > serious pain. > > So, yes. > > 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 Sat Aug 16 10:20:36 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Sat, 16 Aug 2008 14:20:36 +0000 Subject: [time-nuts] I want a good micro-controller In-Reply-To: Your message of "Sat, 16 Aug 2008 08:36:05 -0400." <48A6C9B5.8040607@quackers.net> Message-ID: <64367.1218896436@critter.freebsd.dk> Having spent 30 years programming things, let me just add this: The original PIC chips have a strange software architecture, but it uses very little silicon real-estate, which is why we suddenly could program things in DIP-8 format. If that is your business, they're not bad for the job. A good example of this kind of application is TVB's PPS divider in a PIC16F84 Once you get to program your stuff in 'C' or other high level languages you shouldn't need to bother with the software architecture, instead concentrate on what I/O, bootloading and what else is important. The fact that people program PIC's in BASIC is fine with me, in fact I think it has gotten a lot of people hooked on programming who would otherwise never have tried. If I started a project today, I would seriously consider ARM chips, which come from very small (LPC2103) and all the way up to what runs the iPhone and GCC has good arm support. Olimex.com (resold by sparkfun) has tons of different prototyping cards with all sorts of chips, browse around and find something you like. -- 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 newell at cei.net Sat Aug 16 10:37:21 2008 From: newell at cei.net (Scott Newell) Date: Sat, 16 Aug 2008 09:37:21 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A6C9B5.8040607@quackers.net> References: <48A6C9B5.8040607@quackers.net> Message-ID: <200808161437.m7GEbRaG006043@host22.the-web-host.com> At 07:36 AM 8/16/2008, wje wrote: >I have both EE and CS degrees, and I work in both worlds. In my humble >(but completely accurate and stable) opinion, Basic is not a programming >language. It's a tool of Satan designed to convince people that they are >programmers when they really should stick to their janitorial duties. >This is a subset of the general problem that everyone thinks they are >programmers, and usually think their code is perfect. But, that's a rant >for a different audience. So, how do you tell if you're not a programmer, but pretending to be one? My code is far from perfect, but it can usually be made to get the job done. I try not to cut too many corners, and the ones that I do cut bother me. But when you're the lone programmer on projects, it's hard to know if you're crummy or decent, since there's no one to measure against. (Of course, there's the metric of 'product shipped, product works, bossman happy, paycheck cashed', but that doesn't distinguish between good and bad programmers, just programmers that can fool others along with themselves.) -- newell N5TNL From t_list_1_only at braw.co.uk Sat Aug 16 10:46:42 2008 From: t_list_1_only at braw.co.uk (David ) Date: Sat, 16 Aug 2008 15:46:42 +0100 Subject: [time-nuts] NavSync CW12 and CW25 In-Reply-To: Message-ID: <000a01c8ffae$ea724990$0200a8c0@hp6110> (time-nuts Digest, Vol 49, Issue 14) Ed, a couple of rather delayed answers to your CW25 thoughts: > but if you changed the output frequency of the CW25 is it >possible that you might find a 'sweet spot' that would give > you a cleaner signal I've not experimented with that, it affects the simplicity of the synthesis design and it may not be that important. The PLL that locks the OCXO to the 'GPS' reference will have a very narrow bandwidth and operates a little like a LPF to minimize the transfer of 'GPS' phase noise sidebands & spurs to the OCXO. Finding a useful "sweet spot" frequency needs an appropriate way of dividing the OCXO down so the frequencies match in the PSD. In my system the initial loop is a 0.3 Hz bandwith, this is rather loose to get things going. It's now working and given some free time (Ha!) the loop bandwidth can probably come down by about a factor of 10, this may further clean the output signal. The most important consideration is what is happening very close to the carrier rather than noise and spurs much beyond 1kHz from carrier which will be heavily attenuated by the PLL. > Did you divide down the output from the CW12? Yes. I initially thought about a discrete system and did not quickly find the phase / frequency PSD I wanted (MC4044). I looked at modern monolithic synthesizers and was put off many due to the need for some form of controller to load and control them. I do have a bag of (long obsolete) PICs which I use for this sort of thing but additionally many of the modern monolithic synthesisers are not specified for frequencies as low as 10MHz although they may work well. About this time my raking through the recycling buckets found a few MC145152FN2 parts which are parallel load so just needed some hard wire links to set the signal and reference divider ratios, easy. The limitation in this application is that the reference divider is limited to ratios of 2^N, so in my toy N=7, the division is 128 in both paths. Contact me off list if you want one posted to you, I suspect they have been off the market for years. At the moment the OCXO is happily locking down and vastly cleaner than the CW25 output, given time I want to modify my 60kHz (MSF) time signal receiver before I review the PLL in the GPS. Regards David From holrum at hotmail.com Sat Aug 16 11:32:52 2008 From: holrum at hotmail.com (Mark Sims) Date: Sat, 16 Aug 2008 15:32:52 +0000 Subject: [time-nuts] LPRO-101 internals In-Reply-To: References: Message-ID: The rubidium lamp is glowing a nice violet color... does not seem to be any red. I need to compare it to one of the other units. If I start tweaking turny things, I would record the position of the device, turn it say 1/2 a turn and see if it made things better or worse. If better, we are done. If no change, return it to its original setting. If worse then turn it 1/2 turn the other direction. Those 21 internal jumpers seem to indicate that the unit is infinitely (OK, 2 millionly) configurable. It would be nice to know what those jumpers do. There has to be something useful there... One thing that I did not see was some kind of crystal... I assume it is either on the back of the board or in the lamp assembly (which gets rather hot for an OCXO oven). ---------------------------------------- _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From wje at quackers.net Sat Aug 16 12:10:18 2008 From: wje at quackers.net (wje) Date: Sat, 16 Aug 2008 12:10:18 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <200808161437.m7GEbRaG006043@host22.the-web-host.com> References: <48A6C9B5.8040607@quackers.net> <200808161437.m7GEbRaG006043@host22.the-web-host.com> Message-ID: <48A6FBEA.80907@quackers.net> You certainly don't need formal training to be a good programmer; I've seen plenty of code from CS grads that's terrible, and very nice code from art majors. In my book, a good program is one one that's organized logically, well documented, and performs the job it was designed to do. A god programmer is someone that produces such programs. That's it. The problem is that, with the advent PCs and easily-accessible programming tools, everyone thinks they can write code, and many can't. Then what you end up with is a tangled mess that's unmaintainable and indecipherable. It's interesting that any number of EE's will take great care in circuit design, but then throw together some poorly-designed code to run their beautiful circuit. But, this has been endemic in the hardware industry for as long as I've been around. Hardware companies frequently have the attitude that it's the hardware that's important and the software is just one of those minor bits that has to get tacked on. This was true even for some companies that should have known better; there were plenty of HW engineers I ran into back in the old Digital days that, even though they were building minicomputers, really considered software an unfortunate requirement that had to be shipped with their beautiful hardware. Ah well, this is really wandering off-topic and my blood pressure's going up. I think I'll go write some C code for an 8-bit micro to calm down. And yes, I use vi. :) Bill Ezell ---------- They said 'Windows or better' so I used Linux. Scott Newell wrote: At 07:36 AM 8/16/2008, wje wrote: I have both EE and CS degrees, and I work in both worlds. In my humble (but completely accurate and stable) opinion, Basic is not a programming language. It's a tool of Satan designed to convince people that they are programmers when they really should stick to their janitorial duties. This is a subset of the general problem that everyone thinks they are programmers, and usually think their code is perfect. But, that's a rant for a different audience. So, how do you tell if you're not a programmer, but pretending to be one? My code is far from perfect, but it can usually be made to get the job done. I try not to cut too many corners, and the ones that I do cut bother me. But when you're the lone programmer on projects, it's hard to know if you're crummy or decent, since there's no one to measure against. (Of course, there's the metric of 'product shipped, product works, bossman happy, paycheck cashed', but that doesn't distinguish between good and bad programmers, just programmers that can fool others along with themselves.) From bill at iaxs.net Sat Aug 16 14:06:26 2008 From: bill at iaxs.net (Bill Hawkins) Date: Sat, 16 Aug 2008 13:06:26 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A6FBEA.80907@quackers.net> References: <48A6C9B5.8040607@quackers.net><200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> Message-ID: <000001c8ffca$cd217de0$021ba8c0@cyrus> As long as we're off topic, but interesting - I was born in 1938. MIT had a 704 and punch cards and maybe FORTRAN in the fifties. A classmate wrote FORTH as a portable program for big telescopes. Programming tools have run off in different directions since then, just as today's tool section in a Big Box is very different from before the baby boom hit the market. Everybody that needs a tool has a good chance of finding what they're looking for, but they'll look for what they've used before or maybe a little better. Y'see, the human brain only weighs three pounds. It hasn't been possible to fit the sum of human knowledge into one brain for one or two hundred years, depending on the capability of the brain. So we have to specialize, and the specialties keep getting narrower. I helped design an industrial process control system in the eighties. One architect couldn't do it - it took one for hardware (Motorola 68K), one for programming (Unix), and one for process control (me, with 20 years of industrial control experience). It was a grand educational experience. So when someone says that this or that tool is absolutely useless, I take that as a sign of narrow specialization, in the dark about the rest of the world but egocentrically sure the rest of the world must be like them. It's a law of human nature, like "The prospect of wealth motivates deceit." Today's politicians seem unable to suppress that motivation. Veering back towards the list topic, I found this in "Four Laws that Drive the Universe" by Peter Atkins (it's about thermodynamics): "Energy is conserved because time is uniform: time flows steadily, it does not bunch up and run faster then spread out and run slowly. ... If time were to bunch up and spread out, then energy would not be conserved." But maybe uniform time is only a local effect, on the scale of the Universe. As far as we know, conservation of energy is not violated, so we have to find the causes of observed time variations in the hardware we've built or the programs we've written. Wait, what about Einstein's relativity? The flow of time is still uniform in a manner that can be predicted from the equations. Bill Hawkins -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of wje Sent: Saturday, August 16, 2008 11:10 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] I want a good micro-controller You certainly don't need formal training to be a good programmer; I've seen plenty of code from CS grads that's terrible, and very nice code from art majors. In my book, a good program is one one that's organized logically, well documented, and performs the job it was designed to do. A good programmer is someone that produces such programs. That's it. The problem is that, with the advent PCs and easily-accessible programming tools, everyone thinks they can write code, and many can't. Then what you end up with is a tangled mess that's unmaintainable and indecipherable. It's interesting that any number of EE's will take great care in circuit design, but then throw together some poorly-designed code to run their beautiful circuit. But, this has been endemic in the hardware industry for as long as I've been around. Hardware companies frequently have the attitude that it's the hardware that's important and the software is just one of those minor bits that has to get tacked on. This was true even for some companies that should have known better; there were plenty of HW engineers I ran into back in the old Digital days that, even though they were building minicomputers, really considered software an unfortunate requirement that had to be shipped with their beautiful hardware. Ah well, this is really wandering off-topic and my blood pressure's going up. I think I'll go write some C code for an 8-bit micro to calm down. And yes, I use vi. :) Bill Ezell ---------- They said 'Windows or better' so I used Linux. Scott Newell wrote: At 07:36 AM 8/16/2008, wje wrote: I have both EE and CS degrees, and I work in both worlds. In my humble (but completely accurate and stable) opinion, Basic is not a programming language. It's a tool of Satan designed to convince people that they are programmers when they really should stick to their janitorial duties. This is a subset of the general problem that everyone thinks they are programmers, and usually think their code is perfect. But, that's a rant for a different audience. So, how do you tell if you're not a programmer, but pretending to be one? My code is far from perfect, but it can usually be made to get the job done. I try not to cut too many corners, and the ones that I do cut bother me. But when you're the lone programmer on projects, it's hard to know if you're crummy or decent, since there's no one to measure against. (Of course, there's the metric of 'product shipped, product works, bossman happy, paycheck cashed', but that doesn't distinguish between good and bad programmers, just programmers that can fool others along with themselves.) _______________________________________________ time-nuts mailing list -- 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 rfnuts at arcor.de Sat Aug 16 14:18:32 2008 From: rfnuts at arcor.de (Adrian) Date: Sat, 16 Aug 2008 20:18:32 +0200 Subject: [time-nuts] LPRO-101 internals In-Reply-To: References: Message-ID: <48A719F8.8050901@arcor.de> Mark, things wont get better by fooling around with the trimpots, IMO. Chances are some of the pots are quite sesitive, thus impossible to bring back to proper settings w/o detailed knowledge about the alignment procedure. I would refer to the LPRO manual that, unfortunately, doesn't contain detailed circuit and alignment information, but at least some basic functional diagrams. Then, put a manual from a well documented Rb (like the FRS) aside and try to re-engineer a detailed block diagram. This will show you how much it differs from the FRS, and what parts of the FRS manual are or aren't useful for your task. It should also show most of the functionality of the trim pots. That way, without having turned any pots, you'll have learned a lot about how the unit works, and that should be quite helpful for troubleshooting. Adrian Mark Sims schrieb: > The rubidium lamp is glowing a nice violet color... does not seem to be any red. I need to compare it to one of the other units. > > If I start tweaking turny things, I would record the position of the device, turn it say 1/2 a turn and see if it made things better or worse. If better, we are done. If no change, return it to its original setting. If worse then turn it 1/2 turn the other direction. > > Those 21 internal jumpers seem to indicate that the unit is infinitely (OK, 2 millionly) configurable. It would be nice to know what those jumpers do. There has to be something useful there... > > One thing that I did not see was some kind of crystal... I assume it is either on the back of the board or in the lamp assembly (which gets rather hot for an OCXO oven). > ---------------------------------------- > > _________________________________________________________________ > Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. > http://clk.atdmt.com/MRT/go/108588797/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 Sat Aug 16 16:28:12 2008 From: cdelect at juno.com (corby d dawson) Date: Sat, 16 Aug 2008 13:28:12 -0700 Subject: [time-nuts] Oscillators on eBay Message-ID: <20080816.132813.-651453.3.cdelect@juno.com> Hi, I listed some frequency standard related items on eBay and will be listing some more in the next week or so. search items by seller corbymite Cheers! Corby Dawson ____________________________________________________________ Get credit card help today. Safe, fast, and easy. Click Now. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m2DVEnCitPqF2XZrte7CfOtBRWnkHUz5bpTMlZ9Gh8ofDPr/ From holrum at hotmail.com Sat Aug 16 17:12:18 2008 From: holrum at hotmail.com (Mark Sims) Date: Sat, 16 Aug 2008 21:12:18 +0000 Subject: [time-nuts] LPRO-101 internals In-Reply-To: References: Message-ID: I am already rather familiar with the workings of rubidium oscillators... I have built my own before (just for fun, using a salvaged physics package). The LPRO only has one adjustmnent pot (besides the frequency trim pot). All the other adjustments are trimmer caps and inductors. The first thing to try is that select-to-test resistor. Then the trim pot. If neither of those makes things better, I suspect that the inductors and capacitors will not help either. It is not worth spending more than a couple millichrons trying to reverse engineer the LPRO design when you can buy them for less than $100. I'd much rather just break out the diddle stick and start diddling the heck out of it... goes well my philosophy of "If it jams, force it. It it breaks, it needed fixing anyway." Only thing is the darn thing is working now. I guess the sight of my collection of diddle sticks and that 5 pound sledgehammer in the corner convinced it that it had better start behaving. ---------------------------------------- things wont get better by fooling around with the trimpots, IMO. Chances are some of the pots are quite sesitive, thus impossible to bring back to proper settings w/o detailed knowledge about the alignment procedure. I would refer to the LPRO manual that, unfortunately, doesn't contain detailed circuit and alignment information, but at least some basic functional diagrams. Then, put a manual from a well documented Rb (like the FRS) aside and try to re-engineer a detailed block diagram. This will show you how much it differs from the FRS, and what parts of the FRS manual are or aren't useful for your task. It should also show most of the functionality of the trim pots. That way, without having turned any pots, you'll have learned a lot about how the unit works, and that should be quite helpful for troubleshooting. _________________________________________________________________ Get ideas on sharing photos from people like you. Find new ways to share. http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 From didier at cox.net Sat Aug 16 19:00:17 2008 From: didier at cox.net (Didier Juges) Date: Sat, 16 Aug 2008 18:00:17 -0500 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A6FBEA.80907@quackers.net> References: <48A6C9B5.8040607@quackers.net><200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> Message-ID: <003401c8fff3$da43a060$0a01a8c0@didierhp> That is an interesting thread. So I feel like I have to add my $0.02 I am a casual programmer. I got into programming when I had to, because it was, at one time, the path of least resistance for something I wanted to do. I am otherwise an EE. Today, I spend my time 50/50 doing hardware design and software design. Most my software is embedded software, with a few exceptions. I am in the interesting position of having written (and re-written) essentially the same desktop application under 4 different environments: QuickBasic 4.5 (I can hear teeth clinching...), Microsoft QuickC 2.5 (MS-DOS), gcc under Linux and Visual Basic 6.0, so I think I can compare the environments and the results pretty well. While the visual appeal (eye candy) of the VB 6.0 version is undeniable, by far the easiest to maintain (and with fewest bugs) is the gcc version. Feature-wise, it matches the VB 6.0 version, but in different ways. It is not as pretty (ncurses on an 80x24 terminal is NOT eye-candy) but it does things that I have not even contemplated doing under VB. Basic (and Visual Basic) go out of their way to make things easy, and as a result allow way too many bugs (I call them undocumented features). They are great to quickly simulate a user interface, or for a quick tool, but you do not want to write large programs with it. Even though I know people who have done it successfully, I myself have not been successful with it. It is just too hard to do the right thing with Basic, it encourages slopiness. Other than the PC, I write a fair amount of code for the 8051 and it's variants, in C, using either the Keil compiler, or more recently the SDCC. I have done a good bit of assembly for the Motorola 68HC05 way back (and the 8008 even farther back), and I am very glad this is over. The Motorola architectures are usually pretty well done, but assembly? Pleeeeaaase... (actually not quite over yet, I have my version of the 10 MHz-PPS divider originally by TVB, mine runs on an 8051 and is written in assembly too) In general, I find C programs easy to write and easy to maintain, and C matches well with my hardware background. Didier KO4BB From dave.mallery at gmail.com Sat Aug 16 19:26:14 2008 From: dave.mallery at gmail.com (Dave Mallery) Date: Sat, 16 Aug 2008 17:26:14 -0600 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A6FBEA.80907@quackers.net> References: <48A6C9B5.8040607@quackers.net> <200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> Message-ID: <3010c9470808161626q389d5e24m4e933a66c83a6734@mail.gmail.com> bill but wasn't that hardware beautiful??? (gazes at 11/70 backplane on wall...) dave On Sat, Aug 16, 2008 at 10:10 AM, wje wrote: > You certainly don't need formal training to be a good programmer; I've > seen plenty of code from CS grads that's terrible, and very nice code > from art majors. > In my book, a good program is one one that's organized logically, well > documented, and performs the job it was designed to do. A god > programmer is someone that produces such programs. That's it. The > problem is that, with the advent PCs and easily-accessible programming > tools, everyone thinks they can write code, and many can't. Then what > you end up with is a tangled mess that's unmaintainable and > indecipherable. > It's interesting that any number of EE's will take great care in > circuit design, but then throw together some poorly-designed code to > run their beautiful circuit. But, this has been endemic in the hardware > industry for as long as I've been around. Hardware companies frequently > have the attitude that it's the hardware that's important and the > software is just one of those minor bits that has to get tacked on. > This was true even for some companies that should have known better; > there were plenty of HW engineers I ran into back in the old Digital > days that, even though they were building minicomputers, really > considered software an unfortunate requirement that had to be shipped > with their beautiful hardware. > Ah well, this is really wandering off-topic and my blood pressure's > going up. I think I'll go write some C code for an 8-bit micro to calm > down. And yes, I use vi. :) > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > Scott Newell wrote: > > At 07:36 AM 8/16/2008, wje wrote: > > > > I have both EE and CS degrees, and I work in both worlds. In my humble > (but completely accurate and stable) opinion, Basic is not a programming > language. It's a tool of Satan designed to convince people that they are > programmers when they really should stick to their janitorial duties. > This is a subset of the general problem that everyone thinks they are > programmers, and usually think their code is perfect. But, that's a rant > for a different audience. > > > So, how do you tell if you're not a programmer, but pretending to be > one? My code is far from perfect, but it can usually be made to get > the job done. I try not to cut too many corners, and the ones that I > do cut bother me. But when you're the lone programmer on projects, > it's hard to know if you're crummy or decent, since there's no one to > measure against. (Of course, there's the metric of 'product shipped, > product works, bossman happy, paycheck cashed', but that doesn't > distinguish between good and bad programmers, just programmers that > can fool others along with themselves.) > > > > _______________________________________________ > time-nuts mailing list -- 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 8.04) PO Box 3519; T or C, NM 87901 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 bruceraymond at ameritech.net Sat Aug 16 19:38:11 2008 From: bruceraymond at ameritech.net (Bruce Raymond) Date: Sat, 16 Aug 2008 19:38:11 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <003401c8fff3$da43a060$0a01a8c0@didierhp> References: <48A6C9B5.8040607@quackers.net><200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> <003401c8fff3$da43a060$0a01a8c0@didierhp> Message-ID: <48A764E3.9000801@ameritech.net> Hi all, I'm a lurker and decided to stick my neck out a little. I, too started out as a hardware engineer. In this case real hardware - I did structural analysis of nuclear components. That was a few lifetimes ago. I'm doing software now. I'm in agreement with the comments about Basic being conducive to sloppy programming. I want my compiler to do as much checking as possible, and that's not in line with Basic. I'm partial to C for embedded applications. The PIC architecture is truly atrocious. However, I've been using PICs for years and am familiar with the development environment. I'm not in a hurry to learn something else for casual use. The C compilers for PICs play games with creating a pseudo stack by reallocating memory. I'd hate to have to do that manually, but it seems to work alright when implemented by compiler. My actual contribution to the thread is a link to a free C compiler for PICs that works pretty well. I have been using the CCS compiler and switched to this one. www.sourceboost.com/ Bruce Raymond/ND8I Didier Juges wrote: > That is an interesting thread. So I feel like I have to add my $0.02 > > I am a casual programmer. I got into programming when I had to, because it > was, at one time, the path of least resistance for something I wanted to do. > I am otherwise an EE. Today, I spend my time 50/50 doing hardware design and > software design. Most my software is embedded software, with a few > exceptions. > > I am in the interesting position of having written (and re-written) > essentially the same desktop application under 4 different environments: > QuickBasic 4.5 (I can hear teeth clinching...), Microsoft QuickC 2.5 > (MS-DOS), gcc under Linux and Visual Basic 6.0, so I think I can compare the > environments and the results pretty well. > > While the visual appeal (eye candy) of the VB 6.0 version is undeniable, by > far the easiest to maintain (and with fewest bugs) is the gcc version. > Feature-wise, it matches the VB 6.0 version, but in different ways. It is > not as pretty (ncurses on an 80x24 terminal is NOT eye-candy) but it does > things that I have not even contemplated doing under VB. > > Basic (and Visual Basic) go out of their way to make things easy, and as a > result allow way too many bugs (I call them undocumented features). They are > great to quickly simulate a user interface, or for a quick tool, but you do > not want to write large programs with it. Even though I know people who have > done it successfully, I myself have not been successful with it. It is just > too hard to do the right thing with Basic, it encourages slopiness. > > Other than the PC, I write a fair amount of code for the 8051 and it's > variants, in C, using either the Keil compiler, or more recently the SDCC. I > have done a good bit of assembly for the Motorola 68HC05 way back (and the > 8008 even farther back), and I am very glad this is over. The Motorola > architectures are usually pretty well done, but assembly? Pleeeeaaase... > (actually not quite over yet, I have my version of the 10 MHz-PPS divider > originally by TVB, mine runs on an 8051 and is written in assembly too) > > In general, I find C programs easy to write and easy to maintain, and C > matches well with my hardware background. > > Didier KO4BB > > > _______________________________________________ > time-nuts mailing list -- 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 Sat Aug 16 21:15:38 2008 From: holrum at hotmail.com (Mark Sims) Date: Sun, 17 Aug 2008 01:15:38 +0000 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: Begin rant { I have been programming stuff since 1970 (IBM1130 in high school). I have programmed well over 100 different machines in far more than that many languages. You would be hard pressed to find a machine architecture/real lanuage that I have not used. I also have an EE degree and have designed several commercially available computers (and a couple of successful ones at that). I have done some pretty incredible things with PIC chips. I used them mainly because of their very predictable execution time per instruction. Apps included generating eight simultaneous channels of real time video syncs/time code overlays, a 3DES encrypted full duplex audio radio with 32 channels of PWM I/O and telemetry, the complete flight control system for an autonomous aircraft, etc. One application replaced over 100 TTL/PAL packages with a single 18 pin PIC. The TVB clock divider is a perfect application of a PIC progammed in assembly language (use the Parallax syntax, not that horrid Microchip babel). That said, PICs are a sorry, miserable excuse for a microprocessor. Paged memory is just so last millenium. It should have died an unlamented death in the 60's. Compilers and programmers waste a huge amount of time and CPU cycles fiddling with pages, etc. Same goes for the 8051's and their demon spawn. You can gussy up a toad with all the lipstick in the world, and it's still a toad. If you are going to program a micro in C, go with an AVR. They are not perfect, but at least they don't croak. End rant } ---------------------------------------- _________________________________________________________________ Get thousands of games on your PC, your mobile phone, and the web with Windows?. http://clk.atdmt.com/MRT/go/108588800/direct/01/ From cupido at mail.ua.pt Sat Aug 16 22:00:56 2008 From: cupido at mail.ua.pt (Luis Cupido) Date: Sun, 17 Aug 2008 03:00:56 +0100 Subject: [time-nuts] Designing and building an OCXO and GPSDO In-Reply-To: <48A5F02E.9090902@xtra.co.nz> References: <48A40F1C.4020800@mail.ua.pt> <48A4199C.5010109@xtra.co.nz> <48A4D3F1.3050007@mail.ua.pt> <48A4E039.1070900@xtra.co.nz> <48A4E476.1060508@xtra.co.nz> <48A5699B.4070303@mail.ua.pt> <48A5F02E.9090902@xtra.co.nz> Message-ID: <48A78658.8040704@mail.ua.pt> Bruce, John, Tks for all your comments about that topic. really interesting. Luis Cupido. ct1dmk. Bruce Griffiths wrote: > Luis Cupido wrote: >> Bruce, >> John, >> ... >> >> And at smaller offsets like 100Hz and less ? >> Shouldn't the improvement be even bigger ? >> Closer to the carrier we are dealing with bigger signals >> so the ADC issues like resolution should be less important, >> and the limiting factor should really be the the >> phase noise of the LO's and etc. >> Am I right ? >> >> >> Luis Cupido. >> ct1dmk. >> >> >> >> > Luis > > The R&S FMU 36 is a baseband analyser employing a pair of 80MSPS ADCs so > only the preamp, ADC, and 80MHz oscillator phase noise should be > significant (assuming the calculation roundoff noise isnt a factor). > > 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 wje at quackers.net Sat Aug 16 22:49:35 2008 From: wje at quackers.net (wje) Date: Sat, 16 Aug 2008 22:49:35 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <3010c9470808161626q389d5e24m4e933a66c83a6734@mail.gmail.com> References: <48A6C9B5.8040607@quackers.net> <200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> <3010c9470808161626q389d5e24m4e933a66c83a6734@mail.gmail.com> Message-ID: <48A791BF.6020004@quackers.net> Well, yes, it was. The first computer I actually owned was a PDP-8, essentially stolen in pieces from the DEC scrapyard. Core memory, who would have imagined that it would actually work? I mean, you could actually see the bits. And it had blinking lights, too. I still insist a computer isn't a real computer without blinking lights. Which leads to yet another little side diversion... there was some really fantastic hardware done back in the '70s and '80s, without the benefit of DSPs, FPGAs, or microprocessors that had more power than a modern wristwatch. I love reconditioning equipment from that era, and it's remarkable what could be done with a handful of discrete components that today is done with a million transistors worth of ICs. My oldest working device is a 5061A from '68, not counting useless things like my saturated-cell voltage standard; my favorite is a tie between my HP 5370A and my Solartron 7081 laboratory dvm. Another little gem (in my opinion at least) is the Polarad 632 spectrum analyzer. They're not exceptional by any modern measure, but they're dirt-cheap and do manage better than 120 db noise floor and a 10 Khz to 2 Ghz range. Plus, they have a nifty discrete IC digital video capture board that does scan storage, scan averaging, and peak detection, all without a single microprocessor in sight. Which reminds me, what happened to all that wonderful European engineering from companies like Datron and Solartron? Their equipment frequently beat the pants off of anything we were doing at that time (as I gaze lovingly at my pair of Datron 4910's). Bill Ezell ---------- They said 'Windows or better' so I used Linux. Dave Mallery wrote: bill but wasn't that hardware beautiful??? (gazes at 11/70 backplane on wall...) dave On Sat, Aug 16, 2008 at 10:10 AM, wje [1] wrote: You certainly don't need formal training to be a good programmer; I've seen plenty of code from CS grads that's terrible, and very nice code from art majors. In my book, a good program is one one that's organized logically, well documented, and performs the job it was designed to do. A god programmer is someone that produces such programs. That's it. The problem is that, with the advent PCs and easily-accessible programming tools, everyone thinks they can write code, and many can't. Then what you end up with is a tangled mess that's unmaintainable and indecipherable. It's interesting that any number of EE's will take great care in circuit design, but then throw together some poorly-designed code to run their beautiful circuit. But, this has been endemic in the hardware industry for as long as I've been around. Hardware companies frequently have the attitude that it's the hardware that's important and the software is just one of those minor bits that has to get tacked on. This was true even for some companies that should have known better; there were plenty of HW engineers I ran into back in the old Digital days that, even though they were building minicomputers, really considered software an unfortunate requirement that had to be shipped with their beautiful hardware. Ah well, this is really wandering off-topic and my blood pressure's going up. I think I'll go write some C code for an 8-bit micro to calm down. And yes, I use vi. :) Bill Ezell ---------- They said 'Windows or better' so I used Linux. Scott Newell wrote: At 07:36 AM 8/16/2008, wje wrote: I have both EE and CS degrees, and I work in both worlds. In my humble (but completely accurate and stable) opinion, Basic is not a programming language. It's a tool of Satan designed to convince people that they are programmers when they really should stick to their janitorial duties. This is a subset of the general problem that everyone thinks they are programmers, and usually think their code is perfect. But, that's a rant for a different audience. So, how do you tell if you're not a programmer, but pretending to be one? My code is far from perfect, but it can usually be made to get the job done. I try not to cut too many corners, and the ones that I do cut bother me. But when you're the lone programmer on projects, it's hard to know if you're crummy or decent, since there's no one to measure against. (Of course, there's the metric of 'product shipped, product works, bossman happy, paycheck cashed', but that doesn't distinguish between good and bad programmers, just programmers that can fool others along with themselves.) _______________________________________________ time-nuts mailing list -- [2]time-nuts at febo.com To unsubscribe, go to [3]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:wje at quackers.net 2. mailto:time-nuts at febo.com 3. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From kg7tnt at msn.com Sat Aug 16 16:04:27 2008 From: kg7tnt at msn.com (Timothy Parham Sr) Date: Sat, 16 Aug 2008 20:04:27 -0000 Subject: [time-nuts] Nixie - tube clock - 16 Digit Readout ! Message-ID: Greetings to all , ! Happy to be added to the group : ) My finding a few nixies in a box that was given to me a few months ago has lead me to " here " * I have been on a quest to find the " RIGHT " nixie clock kit , whatever that really is --> I have done some thinking & now find myself wanting to colaborate with someone willing to tackle this project with me , In spite of my being an " EXTRA - CLASS - Opperator " = Ham call sign KG7TNT.... I have a limited ability to feel comfortable with reading scematics & translating that image to a PCB. I know that I can solder & recognise a power supply when I see it , I guess I'm just a bit overwhelmed with " where does it go to make it all work " ...... I'm mostly wanting to make a clock that shows the display as : 2008 * 12 * 31 * 59 * 59 *59 * 59 year * Month * Day * Hour * Minute * Second * 1/10 seconds .... And ! I found it only - fitting to have the background of this clock ; A movie poster of : THE - TIME - MACHINE ! I thank you all in advance for any &nd all help , I absolutely do appreciate it ; ) All for now , Tim From fortime at bellsouth.net Sun Aug 17 00:17:52 2008 From: fortime at bellsouth.net (phil) Date: Sun, 17 Aug 2008 00:17:52 -0400 Subject: [time-nuts] SatStat talk to 58534A ? Message-ID: <001301c90020$3814a3c0$a101a8c0@officemail> Does anyone know if the Symmetricom SatStat software (Version 5) will talk to a HP/Symmetricom 58534A I've been trying to no avail to get anything out of the 58534A I've been using a B&B Electronics RS422 to RS232 Converter. It locks, I have data on various pairs but trying to figure how to talk to it. I'm not 100 percent on pinouts but tried enough combinations that I should have hit on it ! Any help would be appreciated Thanks, Phil From holrum at hotmail.com Sun Aug 17 08:23:26 2008 From: holrum at hotmail.com (Mark Sims) Date: Sun, 17 Aug 2008 12:23:26 +0000 Subject: [time-nuts] I want a good micro-controller In-Reply-To: References: Message-ID: If you want beautiful hardware, there is absolutely nothing more beautiful than the HP9100A and HP-9100B calculators. Not an IC in them (OK a couple of op amps in the card reader), and VERY few transistors, very fast. Stroke CRT display, mag card reader, external data bus, core memory. Microcode was a 16 layer PCB where intersecting traces on different layers were the bits. Micro sequencer was a braid of memory cores. All the internal execution state was stored in mag cores. You could turn the thing off in mid cycle, throw in down a raging flooded river, retreive a year later, hose it off, turn it back on, and it would resume execution where it left off (this actually happened). See http://www.hpmuseum.org/hp9100.htm ---------------------------------------- _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From jherrero at hvsistemas.es Sun Aug 17 09:23:29 2008 From: jherrero at hvsistemas.es (Javier Herrero) Date: Sun, 17 Aug 2008 15:23:29 +0200 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A791BF.6020004@quackers.net> References: <48A6C9B5.8040607@quackers.net> <200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> <3010c9470808161626q389d5e24m4e933a66c83a6734@mail.gmail.com> <48A791BF.6020004@quackers.net> Message-ID: <48A82651.40603@hvsistemas.es> > I still insist > a computer isn't a real computer without blinking lights. > So you will love the Thinking Machines CM computers... ;) Regards, Javier -- ------------------------------------------------------------------------ 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 jherrero at hvsistemas.es Sun Aug 17 09:26:09 2008 From: jherrero at hvsistemas.es (Javier Herrero) Date: Sun, 17 Aug 2008 15:26:09 +0200 Subject: [time-nuts] Nixie - tube clock - 16 Digit Readout ! In-Reply-To: References: Message-ID: <48A826F1.8060206@hvsistemas.es> Ummm... I did not make it 2000-yr compliant... only 12 digits (yy mm dd hh mm ss) but GPS driven... http://www.hvsistemas.es/Imagenes/reloj.jpg Regards, Javier, EA1CRB Timothy Parham Sr escribi?: > Greetings to all , ! > > Happy to be added to the group : ) > > My finding a few nixies in a box that was given to me a few months ago has lead me to " here " * > > I have been on a quest to find the " RIGHT " nixie clock kit , whatever that really is --> > > I have done some thinking & now find myself wanting to colaborate with someone willing to > tackle this project with me , > In spite of my being an " EXTRA - CLASS - Opperator " = Ham call sign KG7TNT.... > I have a limited ability to feel comfortable with reading scematics & translating that image to a PCB. > I know that I can solder & recognise a power supply when I see it , > I guess I'm just a bit overwhelmed with " where does it go to make it all work " ...... > > I'm mostly wanting to make a clock that shows the display as : > > 2008 * 12 * 31 * 59 * 59 *59 * 59 > year * Month * Day * Hour * Minute * Second * 1/10 seconds > > .... And ! I found it only - fitting to have the background of this clock ; A movie poster of : > > THE - TIME - MACHINE ! > > I thank you all in advance for any &nd all help , I absolutely do appreciate it ; ) > > All for now , > Tim > _______________________________________________ > time-nuts mailing list -- 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 dforbes at dakotacom.net Sun Aug 17 12:13:16 2008 From: dforbes at dakotacom.net (David Forbes) Date: Sun, 17 Aug 2008 09:13:16 -0700 Subject: [time-nuts] Nixie - tube clock - 16 Digit Readout ! In-Reply-To: References: Message-ID: At 8:04 PM +0000 8/16/08, Timothy Parham Sr wrote: >Greetings to all , ! > >Happy to be added to the group : ) > >My finding a few nixies in a box that was given to me a few months >ago has lead me to " here " * > >I have been on a quest to find the " RIGHT " nixie clock kit , >whatever that really is --> > Tim, There is a Yahoo group called NeoNixie that is devoted to the art of creating nixie clocks. A few of its members - the ones who want their clocks to be somewhat accurate - are also members of this group. -- --David Forbes, Tucson, AZ http://www.cathodecorner.com/ From max at maxsmusicplace.com Sun Aug 17 13:06:28 2008 From: max at maxsmusicplace.com (Max Robinson) Date: Sun, 17 Aug 2008 12:06:28 -0500 Subject: [time-nuts] Nixie - tube clock - 16 Digit Readout ! References: <48A826F1.8060206@hvsistemas.es> Message-ID: <007401c9008b$97185c20$6401a8c0@BACKROOM> How long are you going to live? Unless you are a vampire, the 2 and 0 can be hard wired. 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: "Javier Herrero" To: "Discussion of precise time and frequency measurement" Sent: Sunday, August 17, 2008 8:26 AM Subject: Re: [time-nuts] Nixie - tube clock - 16 Digit Readout ! Ummm... I did not make it 2000-yr compliant... only 12 digits (yy mm dd hh mm ss) but GPS driven... http://www.hvsistemas.es/Imagenes/reloj.jpg Regards, Javier, EA1CRB Timothy Parham Sr escribi?: > Greetings to all , ! > > Happy to be added to the group : ) > > My finding a few nixies in a box that was given to me a few months ago has > lead me to " here " * > > I have been on a quest to find the " RIGHT " nixie clock kit , whatever > that really is --> > > I have done some thinking & now find myself wanting to colaborate with > someone willing to > tackle this project with me , > In spite of my being an " EXTRA - CLASS - Opperator " = Ham call sign > KG7TNT.... > I have a limited ability to feel comfortable with reading scematics & > translating that image to a PCB. > I know that I can solder & recognise a power supply when I see it , > I guess I'm just a bit overwhelmed with " where does it go to make it all > work " ...... > > I'm mostly wanting to make a clock that shows the display as : > > 2008 * 12 * 31 * 59 * 59 *59 * 59 > year * Month * Day * Hour * > Minute * Second * 1/10 seconds > > .... And ! I found it only - fitting to have the background of this > clock ; A movie poster of : > > THE - TIME - MACHINE ! > > I thank you all in advance for any &nd all help , I absolutely do > appreciate it ; ) > > All for now , > Tim > _______________________________________________ > time-nuts mailing list -- 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 _______________________________________________ time-nuts mailing list -- 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 Aug 17 15:20:24 2008 From: Murray.Greenman at rakon.com (Murray Greenman) Date: Mon, 18 Aug 2008 07:20:24 +1200 Subject: [time-nuts] SatStat and HP 58534A In-Reply-To: References: Message-ID: Phil, It is very likely that the program WILL work with the 58534A. However, there are several steps to take before you can be sure whether it will or won't. First, you must ensure that your RS422 to RS232 adaptor is working correctly. The TX output should sit idle at -9V (or thereabouts), and be connected to the PC's RX input, which should be close to 0V. Similarly, the same should apply to the PC TX out and adaptor RX in. This might sound obvious, but it is fundamental to the operation, and is easy to check. You may need to use a 'null modem' adaptor to set things right. Next, you must ensure that you have the correct comms speed and parity. Again, fundamental, but please check. Run a dumb terminal program on the PC, one that's easy to use and quick to change the settings on (e.g. Win 3.1 Terminal) - Hyperterminal is too slow and inconvenient. Start with the settings which are the default for the 58534A, and take careful note of the parity it expects. All you need to do is press ENTER on the keyboard. If you get an 'SCPI>' response, well and good. If there's no response, or it's garbled, change the settings and try again. There's no point in trying SatStat until you pass this hurdle. Finally, start SatStat, and use the settings you discovered in the previous step. If things prove really difficult, and you can't find the correct rate, resort to an oscilloscope, and time the bits as the start-up message comes out. This will also confirm for you which pin is the TXD. All units should send 'SCPI>' some time soon after power is applied. It really is simple if you take the steps logically. I've debugged comms to six different GPSDOs in this manner - HP Z3801A, Symm 58503B, HP Z3815A, Chongho GPSR-A, Samsung GCRU-D and Trimble NTSG50AA. Not all of them were on the default settings, but they all responded in SCPI protocol eventually. 73, Murray ZL1BPU From holrum at hotmail.com Sun Aug 17 15:43:21 2008 From: holrum at hotmail.com (Mark Sims) Date: Sun, 17 Aug 2008 19:43:21 +0000 Subject: [time-nuts] LPRO-101 internals In-Reply-To: References: Message-ID: Some more info on the flakey LPRO: I put the cover back on the LPRO that seemed to have magically started working. After a while it went UNLOCK. Took the cover off, LOCK. Seems like mayby a temperature problem after all (or perhaps the cover is affecting the tuning of some component). When looking at the lamp light through the side port of the physics package the color appears a lightish violet. When looking at the lamp base cover (there is a white plastic insert there) the color is more a pinkish red. I measured the LAMP and OXCO control voltages. OCXO is around 7.3V. LAMP is around 5.6V When warming up (even for some time after LOCK is first indicated) the LAMP voltage is unstable... it varies from around 4.3 to 5.7V (usually varying around 0.1V between successive meter readings) ---------------------------------------- _________________________________________________________________ Get ideas on sharing photos from people like you. Find new ways to share. http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 From dlharmon at dlharmon.com Sun Aug 17 17:12:19 2008 From: dlharmon at dlharmon.com (Darrell Harmon) Date: Sun, 17 Aug 2008 16:12:19 -0500 Subject: [time-nuts] Defective rubidium standard wanted Message-ID: <10f611330808171412t7558081w5fd22dd671b26576@mail.gmail.com> I am interested in obtaining a defective rubidium standard to experiment with replacing the control electronics with something more modern. I may also attempt to replace the rubidium lamp with a laser diode. I am located in the US and I am willing to pay for this unit and shipping costs (Paypal or check). Something with schematics available such as an Efratom FRS-C would be preferred. Make an offer. Darrell Harmon From had at to-way.com Sun Aug 17 17:18:34 2008 From: had at to-way.com (Had) Date: Sun, 17 Aug 2008 14:18:34 -0700 Subject: [time-nuts] Sylvania Crystal Diode Book Message-ID: <20080817211836.4388119280A@mail-in04.adhost.com> For those who may not have gotten a copy I was able to obtain an almost "as new" copy and have placed a scan at www.to-way.com. It is a 2MB .pdf, 300 dpi, monochrome. Just click on the title to download. 73 Had, K7MLR From kirbybq at bellsouth.net Sun Aug 17 22:14:45 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Sun, 17 Aug 2008 21:14:45 -0500 Subject: [time-nuts] HP59309A HP-IB Digital Clock In-Reply-To: References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> <038e01c8fe81$d4a99920$04000100@didierhp> Message-ID: <48A8DB15.9090009@bellsouth.net> Anybody have a manual/pdf for a HP 59309A HP-IB Digital Clock ? Thanks - Brian - KD4FM From normn3ykf at stny.rr.com Sun Aug 17 22:21:57 2008 From: normn3ykf at stny.rr.com (Norman J McSweyn) Date: Sun, 17 Aug 2008 22:21:57 -0400 Subject: [time-nuts] HP59309A HP-IB Digital Clock In-Reply-To: <48A8DB15.9090009@bellsouth.net> References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> <038e01c8fe81$d4a99920$04000100@didierhp> <48A8DB15.9090009@bellsouth.net> Message-ID: <48A8DCC5.1000403@stny.rr.com> Brian Kirby wrote: > Anybody have a manual/pdf for a HP 59309A HP-IB Digital Clock ? > > > Thanks - Brian - KD4FM > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ko4bb has one on his manuals page. Have fun! Norm n3ykf From kirbybq at bellsouth.net Sun Aug 17 22:29:56 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Sun, 17 Aug 2008 21:29:56 -0500 Subject: [time-nuts] HP59309A HP-IB Digital Clock In-Reply-To: <48A8DCC5.1000403@stny.rr.com> References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> <038e01c8fe81$d4a99920$04000100@didierhp> <48A8DB15.9090009@bellsouth.net> <48A8DCC5.1000403@stny.rr.com> Message-ID: <48A8DEA4.3070400@bellsouth.net> Thanks - I went there first but I did not see it - I must have been in too much of a hurry - but I found it... Norman J McSweyn wrote: > Brian Kirby wrote: >> Anybody have a manual/pdf for a HP 59309A HP-IB Digital Clock ? >> >> >> Thanks - Brian - 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. >> > ko4bb has one on his manuals page. > Have fun! > Norm n3ykf > > _______________________________________________ > time-nuts mailing list -- 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 Mon Aug 18 03:29:23 2008 From: vilgotch at bigpond.net.au (Morris Odell) Date: Mon, 18 Aug 2008 17:29:23 +1000 Subject: [time-nuts] Nixie - tube clock - 16 Digit Readout ! References: Message-ID: <001901c90104$22e80de0$ad00a8c0@Morris1> A great clock and appropriately flanked by Jim Willams' classic book and an 829B power tube! Have you taken any precautions against cathode poisoning in the nixes that don't see a lot of change? I have never had a problem in any of the clocks I've built but over at the Neonixie group they get quite excited about it. Obligatory time nuts content: my latest clock is GPS controlled, and with an Oncore VP timing receiver too :-) Morris > Date: Sun, 17 Aug 2008 15:26:09 +0200 > From: Javier Herrero > Subject: Re: [time-nuts] Nixie - tube clock - 16 Digit Readout ! > To: Discussion of precise time and frequency measurement > > Message-ID: <48A826F1.8060206 at hvsistemas.es> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Ummm... I did not make it 2000-yr compliant... only 12 digits (yy mm dd > hh mm ss) but GPS driven... http://www.hvsistemas.es/Imagenes/reloj.jpg > > From jherrero at hvsistemas.es Mon Aug 18 04:46:15 2008 From: jherrero at hvsistemas.es (Javier Herrero) Date: Mon, 18 Aug 2008 10:46:15 +0200 Subject: [time-nuts] Nixie - tube clock - 16 Digit Readout ! In-Reply-To: <001901c90104$22e80de0$ad00a8c0@Morris1> References: <001901c90104$22e80de0$ad00a8c0@Morris1> Message-ID: <48A936D7.6050209@hvsistemas.es> Hi, Morris Odell escribi?: > A great clock and appropriately flanked by Jim Willams' classic book and an > 829B power tube! And also some Tektronix Circuit Concepts books ;) > > Have you taken any precautions against cathode poisoning in the nixes that > don't see a lot of change? > The nixies are ZM1210, multiplexed in a 4 x 3 configuration (anodes of three tubes connected together, cathodes of 4 tubes connected together, cathodes are driven by 30 outputs of a Supertex HV5530 driver). The picture was taken in the date and time shown (CET), and of the five units I've built, I've had to replace two years ago one of the nixies due to sputtering. The clock has a routine on startup (rarely, when mains fails) that drives all digits in sequence (showing 11 11 11 11 11 11, 22 22 22 22 22 22, etc...) and when I've seen it, I see no difference in luminosity in the first two digits (the ones that rarely changes), nor in the 10-sec, 10-min (the ones that never shows digits over 5... well... supposedly 10-sec shows a 6 when a leap second occurs... but I've never been there to see it ;) ) nor in the 10-hour, 10-days and 10-month digits. All numbers seems to lit with same intensity. > I have never had a problem in any of the clocks I've built but over at the > Neonixie group they get quite excited about it. > > Obligatory time nuts content: my latest clock is GPS controlled, and with an > Oncore VP timing receiver too :-) This one uses M12T receivers :) The software includes day time savings and configurable time zones (not position-based... seemed way too much complicated ;) ). Regards, Javier -- ------------------------------------------------------------------------ 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 iovane at inwind.it Mon Aug 18 05:56:33 2008 From: iovane at inwind.it (iovane at inwind.it) Date: Mon, 18 Aug 2008 11:56:33 +0200 Subject: [time-nuts] LPRO-101 internals Message-ID: Sometimes trying to fix a faulty unit is simply a challenge. Some more tips. The LPRO with cover removed cannot work in the presence of artificial light coming from AC powered sources!! It locks randomly to the light ripples. My definition of the normal color of the rubidium light would be pink-violet, and the abnormal would be red-violet. The definition of colors may be subjective, but the color should not vary so much after power up. The crystal looks like a transistor (TO5) and has a heatsink. It is located in the corner opposite to the lamp. The other similar component on the board is actually a transistor. Your OCXO Volt is good. I think you have a faulty resistor. Without disassembling the unit, try measuring the voltage at the base of Q703 (1P SMD) located near the lamp assy. At power up it should read some 11 V, and after warm-up it should read some 5 V. If the voltage doesn't drop down, then R721 (61.9K smd, bottom of pcb) might be interrupted: measured onboard it should read some 14K if good, 18K if interrupted. For replacement you could use a 56K and a 5.6K in series. > > Some more info on the flakey LPRO: I put the cover back on the LPRO that seemed to have magically started working. After a while it went UNLOCK. Took the cover off, LOCK. Seems like mayby a temperature problem after all (or perhaps the cover is affecting the tuning of some component). When looking at the lamp light through the side port of the physics package the color appears a lightish violet. When looking at the lamp base cover (there is a white plastic insert there) the color is more a pinkish red. > > I measured the LAMP and OXCO control voltages. OCXO is around 7.3V. LAMP is around 5.6V When warming up (even for some time after LOCK is first indicated) the LAMP voltage is unstable... it varies from around 4.3 to 5.7V (usually varying around 0.1V between successive meter readings) > ---------------------------------------- > > _________________________________________________________________ > Get ideas on sharing photos from people like you. Find new ways to share. > http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 > _______________________________________________ > time-nuts mailing list -- 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 Mon Aug 18 07:16:29 2008 From: vilgotch at bigpond.net.au (Morris Odell) Date: Mon, 18 Aug 2008 21:16:29 +1000 Subject: [time-nuts] HP 5061A problem References: Message-ID: <001201c90123$dce57c40$ad00a8c0@Morris1> Hi all, My 5061A has failed and I've isolated the problem to a faulty A18, the +3500 volt ion pump power supply. The existing one has almost certainly has had the internal 200M resistor go open as the output voltage is about 5 kV and it does not decay quickly when the power is off. The output voltage to the current sensing circuit is 0. I have a replacement which I suspect is faulty - when energised from a +18 volt source it only produces 2 kV which decays quickly and the sensor output is +20 when the thing is unloaded. That 200M resistor may have gone low! Is this one worth installing ie: will +2 kV pump enough ions? So I'm looking for a replacement or advice from anyone who may have attempted to repair one. If anyone has a parts donor of course I'd be happy to pay appropriately including shipping down here to Australia. Morris From holrum at hotmail.com Mon Aug 18 12:54:55 2008 From: holrum at hotmail.com (Mark Sims) Date: Mon, 18 Aug 2008 16:54:55 +0000 Subject: [time-nuts] LPRO-101 internals In-Reply-To: References: Message-ID: Q703 voltages look good (with cover off and unit working). Lamp color seems good (slightly pinkish violet). The room that I am in is lit by DC halogen lamps so not rippley light to worry about. I think I'll try soldering a wire to Q703 and try measuring it with the case on... Another thing to try is to box in just the lamp assembly and see if heat buildup in the lamp box is a problem or if it is heat in the rest of the circuitry. The LPRO cover has an internal box that goes around the lamp assembly. I suspect that it would be heat in the lamp box... but it is pretty striking how much cooler the whole unit runs without the cover on... too bad the cover is also part of the magnetic shielding. ---------------------------------------- _________________________________________________________________ Talk to your Yahoo! Friends via Windows Live Messenger. Find out how. http://www.windowslive.com/explore/messenger?ocid=TXT_TAGLM_WL_messenger_yahoo_082008 From wje at quackers.net Mon Aug 18 13:42:53 2008 From: wje at quackers.net (wje) Date: Mon, 18 Aug 2008 13:42:53 -0400 Subject: [time-nuts] HP 5061A problem In-Reply-To: <001201c90123$dce57c40$ad00a8c0@Morris1> References: <001201c90123$dce57c40$ad00a8c0@Morris1> Message-ID: <48A9B49D.4000203@quackers.net> If you install the second unit, your 5061A still won't work. +20v at the sensor output will signal the ion current monitor to shut down the electron multiplier supply. If you have some high-value resistors around, can you make up a test 200M resistor string? If so, see what happens when that's connected across 4 & 5 of the first 3500 v supply. However, even with the failure case you describe with the first unit, I'd expect your 5061A to still work at least for a short time. Do you have beam current? If not, you might have other problems as well. Check the voltage at A15 pin 4. You should have +18 v or so. If not, more troubleshooting is in order. The danger running without a working ion pump, though, is that at eventually you'll damage the electron multiplier. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Morris Odell wrote: > Hi all, > > My 5061A has failed and I've isolated the problem to a faulty A18, the +3500 > volt ion pump power supply. > > The existing one has almost certainly has had the internal 200M resistor go > open as the output voltage is about 5 kV and it does not decay quickly when > the power is off. The output voltage to the current sensing circuit is 0. > > I have a replacement which I suspect is faulty - when energised from a +18 > volt source it only produces 2 kV which decays quickly and the sensor output > is +20 when the thing is unloaded. That 200M resistor may have gone low! Is > this one worth installing ie: will +2 kV pump enough ions? > > So I'm looking for a replacement or advice from anyone who may have > attempted to repair one. > > If anyone has a parts donor of course I'd be happy to pay appropriately > including shipping down here to Australia. > > Morris > > > _______________________________________________ > time-nuts mailing list -- 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 Mon Aug 18 15:05:36 2008 From: rexa at sonic.net (Rex) Date: Mon, 18 Aug 2008 12:05:36 -0700 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A764E3.9000801@ameritech.net> References: <48A6C9B5.8040607@quackers.net><200808161437.m7GEbRaG006043@host22.the-web-host.com> <48A6FBEA.80907@quackers.net> <003401c8fff3$da43a060$0a01a8c0@didierhp> <48A764E3.9000801@ameritech.net> Message-ID: <48A9C800.3090400@sonic.net> Bruce Raymond wrote: > My actual contribution to the thread is a link to a free C compiler for > PICs that works pretty well. I have been using the CCS compiler and > switched to this one. > > www.sourceboost.com/ > > Bruce Raymond/ND8I > > Bruce, I've been using the CCS C compiler for several years. The PIC has been my main micro, with the help provided by the compiler, but I do sometimes use other micros. At times CCS has driven me nuts with assorted bugs from version to version, but I continue to use it. The main reason I use this compiler is because it has functions that support easy use of many of the features of the PIC. The main one, is that you can define any two pins as a serial port, even ones without the standard UART hardware. Other function support gives easy access for things like timers, delays, interrupts, ADC, PWM, I2C and internal EEPROM read write. After a quick browse of the sourceboost pages, I couldn't figure out if this type of thing is provided in the compiler package (even the top PRO pay version). I'd be interested to hear comments from anyone about support for these PIC features in various compilers. The same type of information for other micro families and compilers welcomed too. On the general micro discussion -- one thing I have noticed is that the PICs seem to be more inclined to go berserk than (say) the 8051 types I have used in the presence of electrical noise. -Rex From n3izn at aol.com Mon Aug 18 16:25:05 2008 From: n3izn at aol.com (n3izn at aol.com) Date: Mon, 18 Aug 2008 16:25:05 -0400 Subject: [time-nuts] Trimble GPS unit on EBAY In-Reply-To: <48A8DCC5.1000403@stny.rr.com> References: <48A2BEC0.50004@quackers.net> <48A2C43D.8080800@mail.ua.pt><48A2D924.3040809@hvsistemas.es> <038e01c8fe81$d4a99920$04000100@didierhp> <48A8DB15.9090009@bellsouth.net> <48A8DCC5.1000403@stny.rr.com> Message-ID: <8CACF87A25725DE-9AC-9B2@webmail-nh06.sysops.aol.com> By the number of hits I got I think every one on here has seen it all ready, but I put another Trimble GPSDO unit on EBAY. Item # 170250179232. I have some other things on there too just look under view seller's other items. Thanks Chris From James.P.Lux at jpl.nasa.gov Mon Aug 18 17:54:11 2008 From: James.P.Lux at jpl.nasa.gov (Jim Lux) Date: Mon, 18 Aug 2008 14:54:11 -0700 Subject: [time-nuts] CE Mark In-Reply-To: <48A5E2CC.9020602@dakotacom.net> References: <2356.1218830781@critter.freebsd.dk> <48A5E2CC.9020602@dakotacom.net> Message-ID: <6.2.5.6.2.20080818144916.02e60248@jpl.nasa.gov> At 01:10 PM 8/15/2008, David Forbes wrote: >Poul-Henning Kamp wrote: > >> > >> In the agreement with the Council, the European Parliament underlines > >> that importers must place only compliant products on the Community > >> market. Before placing a product on the market importers must ensure > >> that [...] > > > > The important thing in this clause is "placing a product on the market". > > > > As long as you import things directly into EU, and never sell them > > again, there is no requirement for CE marking. > > > >Poul, > >This is interesting. It means that I, as an American exporter >selling directly >to end customers in the EU, do NOT need to CE mark my American made products. > >-- David Forbes, Tucson AZ, Estados Unidos Americanos Indeed... I believe that this is also an area where whether something is a kit or a "component destined for inclusion in other equipment" makes a difference. A significant fraction of the expense of getting regulatory approval (for a US RTL, for FCC, for CE, etc.) is actually doing the necessary research and analysis to determine just which standards are applicable, whether they need testing, etc. You can burn up $10K of labor pretty quickly in just writing up the appropriate declarations that "no, our product is exempt because x, and y, and z, in section a of regulation b, says so" Heck, just getting copies of the relevant standards could put a pretty big dent in $10K. As others have pointed out, this is particularly painful if you're a small quantity vendor of inexpensive widgets, since the paperwork handling cost is pretty much independent of the cost of the item being approved/certified/sanctified/exorcised/whathaveyou.. On the other hand, if you're actually PAYing for the engineering time, it might not be a huge fraction of the design and analysis time, except for trivial modifications to existing products that trigger recertification. Jim Lux From didier at cox.net Mon Aug 18 20:24:53 2008 From: didier at cox.net (Didier Juges) Date: Mon, 18 Aug 2008 19:24:53 -0500 Subject: [time-nuts] CE Mark In-Reply-To: <6.2.5.6.2.20080818144916.02e60248@jpl.nasa.gov> References: <2356.1218830781@critter.freebsd.dk><48A5E2CC.9020602@dakotacom.net> <6.2.5.6.2.20080818144916.02e60248@jpl.nasa.gov> Message-ID: <008001c90192$00ab2940$0a01a8c0@didierhp> > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Jim Lux > Sent: Monday, August 18, 2008 4:54 PM > To: dforbes at dakotacom.net; Discussion of precise time and > frequency measurement; Discussion of precise time and > frequency measurement > Subject: Re: [time-nuts] CE Mark > > At 01:10 PM 8/15/2008, David Forbes wrote: > > > >Poul, > > > >This is interesting. It means that I, as an American > >exporter selling directly to end customers in the EU, > >do NOT need to CE mark my American made products. > > > >-- David Forbes, Tucson AZ, Estados Unidos Americanos > It all depends how you intend to sell products in the EU without "placing your product on the market". I am not sure how you can do it "legitimately" and hope to rake in significant sales. You do not need a local distributor to be "placing your product on the market." Advertising is sufficient, catering to the market (by providing sales brochure in local language) is sufficient, a price list in local currency is sufficient. On the other hand, if someone logs on your english-language, US based web site and buys directly in US$ (you sell FOB US) and you don't advertise shipping costs to the foreign country and there is only US-english documentation and the buyer takes care of the importing paperwork, I don't see how you could be accused of "placing your product on the market." If you add the proper disclaimers regarding the fact that your product is not CE compliant and the buyer accepts all liability as a result, I don't see how you could be in trouble. Tokyo Hi-Power (a Japanese ham-radio equipment manufacturer) has done that for a long time. For a while their products were not FCC certified and they did not have a local (US) distributor, yet they would sell to US customers. You had to either call Japan or email to the sales office in Japan and they would give you a price in Yens. They would also ship to you directly if you asked, but none of that was advertised on their web site. This is a little different, since FCC regulations are different from CE regulations, but the spirit is the same. Disclaimer: IANAL, this is just my opinion... Didier KO4BB From wa1zms at att.net Mon Aug 18 20:31:58 2008 From: wa1zms at att.net (wa1zms at att.net) Date: Mon, 18 Aug 2008 20:31:58 -0400 Subject: [time-nuts] HP 5061A problem In-Reply-To: <48A9B49D.4000203@quackers.net> Message-ID: Per the last statement in the message below: "The danger running without a working ion pump, though, is that at eventually you'll damage the electron multiplier." Is it correct to presume then that the EM becomes covered in "cesium splatter" and thus the S/N output gets poor? -Brian, WA1ZMS -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On Behalf Of wje Sent: Monday, August 18, 2008 1:43 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] HP 5061A problem If you install the second unit, your 5061A still won't work. +20v at the sensor output will signal the ion current monitor to shut down the electron multiplier supply. If you have some high-value resistors around, can you make up a test 200M resistor string? If so, see what happens when that's connected across 4 & 5 of the first 3500 v supply. However, even with the failure case you describe with the first unit, I'd expect your 5061A to still work at least for a short time. Do you have beam current? If not, you might have other problems as well. Check the voltage at A15 pin 4. You should have +18 v or so. If not, more troubleshooting is in order. Bill Ezell ---------- They said 'Windows or better' so I used Linux. From wje at quackers.net Mon Aug 18 21:14:29 2008 From: wje at quackers.net (wje) Date: Mon, 18 Aug 2008 21:14:29 -0400 Subject: [time-nuts] HP 5061A problem In-Reply-To: References: Message-ID: <48AA1E75.3050208@quackers.net> Possibly, but from what I remember, the real issue is erosion of the EM dynode surfaces from the high level of ion bombarment, resulting in reduced output and lower S/N, and eventually such low multiplication that the tube is considered 'failed'. Bill Ezell ---------- They said 'Windows or better' so I used Linux. wa1zms at att.net wrote: > Per the last statement in the message below: > > "The danger running without a working ion pump, though, is that at > eventually you'll damage the electron multiplier." > > Is it correct to presume then that the EM becomes covered in > "cesium splatter" and thus the S/N output gets poor? > > -Brian, WA1ZMS > > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of wje > Sent: Monday, August 18, 2008 1:43 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] HP 5061A problem > > > If you install the second unit, your 5061A still won't work. +20v at the > sensor output will signal the ion current monitor to shut down the > electron multiplier supply. > > If you have some high-value resistors around, can you make up a test > 200M resistor string? If so, see what happens when that's connected > across 4 & 5 of the first 3500 v supply. > > However, even with the failure case you describe with the first unit, > I'd expect your 5061A to still work at least for a short time. Do you > have beam current? If not, you might have other problems as well. Check > the voltage at A15 pin 4. You should have +18 v or so. If not, more > troubleshooting is in order. > > > > 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. > > > From dave.g0dja at tiscali.co.uk Tue Aug 19 02:53:34 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Tue, 19 Aug 2008 07:53:34 +0100 Subject: [time-nuts] CE Mark In-Reply-To: <008001c90192$00ab2940$0a01a8c0@didierhp> References: <2356.1218830781@critter.freebsd.dk><48A5E2CC.9020602@dakotacom.net> <6.2.5.6.2.20080818144916.02e60248@jpl.nasa.gov> <008001c90192$00ab2940$0a01a8c0@didierhp> Message-ID: <48AA6DEE.10908@tiscali.co.uk> Didier Juges wrote: > If you add the proper disclaimers regarding the fact that your product is > not CE compliant and the buyer accepts all liability as a result, I don't > see how you could be in trouble. I've asked about US made equipment sold through UK Amateur Radio suppliers, equipment made by companies like Tigertronics and RigBlaster for example, and I'm told that they don't have CE marks. I'm also told that there is at least one UK manufacturer selling add on equipment (mainly audio interfaces) that doesn't put a CE mark on their equipment which they advertise and sell in the UK to European buyers. I wonder how the UK shops/dealers and this, admittedly small, manufacturer, get round the CE mark regulations? I wonder if they are just taking the chance that nothing will go wrong and no one will have the evidence to take them to court or have the resources to prove their gear is non-compliant? If so, and presumably this is a concious decision by the dealers/small manufacturers, why don't many other non-EU and small scale manufacturers and sellers just do the same thing I wonder? Dave From phk at phk.freebsd.dk Tue Aug 19 03:02:54 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Tue, 19 Aug 2008 07:02:54 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Tue, 19 Aug 2008 07:53:34 +0100." <48AA6DEE.10908@tiscali.co.uk> Message-ID: <48226.1219129374@critter.freebsd.dk> In message <48AA6DEE.10908 at tiscali.co.uk>, David Ackrill writes: >I wonder how the UK shops/dealers and this, admittedly small, >manufacturer, get round the CE mark regulations? I wonder if they are >just taking the chance [...] They are. As long as nothing goes wrong, they fine, if something goes wrong, they're royally screwed. -- 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 tvb at LeapSecond.com Tue Aug 19 04:20:18 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Tue, 19 Aug 2008 01:20:18 -0700 Subject: [time-nuts] CE Mark References: <48226.1219129374@critter.freebsd.dk> Message-ID: <001701c901d4$6ae978b0$0300a8c0@pc52> Is software covered by CE regulations, or just hardware? /tvb From phk at phk.freebsd.dk Tue Aug 19 04:24:24 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Tue, 19 Aug 2008 08:24:24 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Tue, 19 Aug 2008 01:20:18 MST." <001701c901d4$6ae978b0$0300a8c0@pc52> Message-ID: <58268.1219134264@critter.freebsd.dk> In message <001701c901d4$6ae978b0$0300a8c0 at pc52>, "Tom Van Baak" writes: >Is software covered by CE regulations, or just hardware? Just hardware. -- 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 didier at cox.net Tue Aug 19 04:35:17 2008 From: didier at cox.net (Didier Juges) Date: Tue, 19 Aug 2008 03:35:17 -0500 Subject: [time-nuts] CE Mark In-Reply-To: <48AA6DEE.10908@tiscali.co.uk> References: <2356.1218830781@critter.freebsd.dk><48A5E2CC.9020602@dakotacom.net> <6.2.5.6.2.20080818144916.02e60248@jpl.nasa.gov><008001c90192$00ab2940$0a01a8c0@didierhp> <48AA6DEE.10908@tiscali.co.uk> Message-ID: <000601c901d6$8310b870$0a01a8c0@didierhp> > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of David Ackrill > Sent: Tuesday, August 19, 2008 1:54 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] CE Mark > > Didier Juges wrote: > > > If you add the proper disclaimers regarding the fact that > your product > > is not CE compliant and the buyer accepts all liability as > a result, I > > don't see how you could be in trouble. > > I've asked about US made equipment sold through UK Amateur > Radio suppliers, equipment made by companies like > Tigertronics and RigBlaster for example, and I'm told that > they don't have CE marks. I'm also told that there is at > least one UK manufacturer selling add on equipment (mainly > audio interfaces) that doesn't put a CE mark on their > equipment which they advertise and sell in the UK to European buyers. > > I wonder how the UK shops/dealers and this, admittedly small, > manufacturer, get round the CE mark regulations? I wonder if > they are just taking the chance that nothing will go wrong > and no one will have the evidence to take them to court or > have the resources to prove their gear is non-compliant? If > so, and presumably this is a concious decision by the > dealers/small manufacturers, why don't many other non-EU and > small scale manufacturers and sellers just do the same thing I wonder? > > Dave > The foreign manufacturers probably figure that the most they have to loose is the business they do in CE countries, which they would not have anyhow otherwise because they can't or won't afford the cost of compliance design or testing. They may be correct as long as their equipment is unlikely to be implicated in a loss of life situation and they are a small company, not worth suing through international tribunals. The situation for the dealer/reseller/distributor is different. They are based in the CE country and they have everything to loose, and I am surprised they would actually do it. Didier KO4BB From iovane at inwind.it Tue Aug 19 06:43:15 2008 From: iovane at inwind.it (iovane at inwind.it) Date: Tue, 19 Aug 2008 12:43:15 +0200 Subject: [time-nuts] LPRO-101 internals Message-ID: A good LPRO works both with cover on or off. > Q703 voltages look good (with cover off and unit working). Lamp color seems good (slightly pinkish violet). The room that I am in is lit by DC halogen lamps so not rippley light to worry about. If the power to the halogen lamp comes from battery, really no problem. If it comes from mains + transformer + rectifier it remains suspicious. My last suggestion: check R705 (100K) and R732 (100K) on the bottom of the PCB. R705 should read some 84K onboard, and R732 some 100K. The lettering around R732 is a bit ambiguous, so look for a 100K resistor in that area. Please let me know Antonio I8IOV From magnus at rubidium.dyndns.org Tue Aug 19 07:30:06 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 19 Aug 2008 13:30:06 +0200 (CEST) Subject: [time-nuts] CE Mark In-Reply-To: <001701c901d4$6ae978b0$0300a8c0@pc52> References: <48226.1219129374@critter.freebsd.dk> <001701c901d4$6ae978b0$0300a8c0@pc52> Message-ID: <9a2a07ae226c0e1298d2f1b35563b057.squirrel@rubidium.dyndns.org> > Is software covered by CE regulations, or just hardware? > /tvb It can be. Consider for instance the software in WLAN-cards, which can allow non-compliant channels for instance. There is no real software/hardware boundary, it is the equipment in its fully functional order that is approved. Infact, runninng a completely different system software that has significantly different behaviour could potentially void the CE mark. Reasnoble changes in software does not void the CE mark. So, you can't get away with "it's only the hardware". Cheers, Magnus From magnus at rubidium.dyndns.org Tue Aug 19 07:30:57 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 19 Aug 2008 13:30:57 +0200 (CEST) Subject: [time-nuts] CE Mark In-Reply-To: <58268.1219134264@critter.freebsd.dk> References: <58268.1219134264@critter.freebsd.dk> Message-ID: > In message <001701c901d4$6ae978b0$0300a8c0 at pc52>, "Tom Van Baak" writes: > >>Is software covered by CE regulations, or just hardware? > > Just hardware. Wrong. See my other notice. Cheers, Magnus From james.p.lux at jpl.nasa.gov Tue Aug 19 09:53:24 2008 From: james.p.lux at jpl.nasa.gov (Jim Lux) Date: Tue, 19 Aug 2008 06:53:24 -0700 Subject: [time-nuts] CE Mark In-Reply-To: <48226.1219129374@critter.freebsd.dk> References: <48226.1219129374@critter.freebsd.dk> Message-ID: <20080819065324.yg7czwe6g48socs8@webmail.jpl.nasa.gov> Quoting Poul-Henning Kamp , on Tue 19 Aug 2008 12:02:54 AM PDT: > In message <48AA6DEE.10908 at tiscali.co.uk>, David Ackrill writes: > >> I wonder how the UK shops/dealers and this, admittedly small, >> manufacturer, get round the CE mark regulations? I wonder if they are >> just taking the chance [...] > > They are. > > As long as nothing goes wrong, they fine, if something goes wrong, > they're royally screwed. This is not necessarily a bad strategy. You'll note that things like defibrillators are not made by big companies with lots of assets (since a defib is one of those things being used on a dying person, and success is not guaranteed, and the family members of one of those non-successes sometimes want someone to sue) You could have a mfr company with small assets that's willing to take the hit and go out of business. The principals could then reform the company under a different name, etc. "piercing the corporate veil" only goes so far. Jim From wa3frp at aol.com Tue Aug 19 11:46:56 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Tue, 19 Aug 2008 11:46:56 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist... Message-ID: <8CAD029F1D74F52-1530-4B6@mblk-d45.sysops.aol.com> I am in the last stage of restoring a 1964 General Radio Frequency Standard Model 1120-AB. I'm having trouble getting the inner oven to work propoerly and the problem has been traced to a defective thermostat in the inner oven. In checking, the thermostat is a thermoswitch manufactured by Princo and is no longer available. My options appear to be: 1. locate a working GR Standard Frequency Oscillator (1113-A) and replace the entire chassis. 2. locate a non-working GR Frequency Oscillator and part it out as needed 3. find a suitable replacement for the original thermoswitch (78 C - closes circuit when temperature is reached) I was wondering if anyone on this list has any sources or leads for #1 and #2 and any opinions on a source for #3. Thanks Russ WA3FRP From cdelect at juno.com Tue Aug 19 12:09:34 2008 From: cdelect at juno.com (corby d dawson) Date: Tue, 19 Aug 2008 09:09:34 -0700 Subject: [time-nuts] 5061A ion pump P/S problem Message-ID: <20080819.090934.-558537.0.cdelect@juno.com> Morris, You implied that you tested the spare module on the bench. You must connect the -side of the supply to the case of the module as well as the pin. (this occurs in the unit by its connection to the chassis) If you don't the supply floats and you will only read about 1/2 the voltage out. Corby Dawson ____________________________________________________________ Stop foreclosure. Click here to stay in your home and rebuild credit. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3meXw3CZz8xwqTtkGi6BkRjldTPOBgIv377yB4vpUn2bMWB7/ From phk at phk.freebsd.dk Tue Aug 19 13:08:32 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Tue, 19 Aug 2008 17:08:32 +0000 Subject: [time-nuts] CE Mark In-Reply-To: Your message of "Tue, 19 Aug 2008 13:30:57 +0200." Message-ID: <62180.1219165712@critter.freebsd.dk> In message , "Ma gnus Danielson" writes: >> In message <001701c901d4$6ae978b0$0300a8c0 at pc52>, "Tom Van Baak" writes: >> >>>Is software covered by CE regulations, or just hardware? >> >> Just hardware. > >Wrong. See my other notice. I hate to nitpick you, but there are no requirements to software anywhere, only to the resulting products behaviour. If you do some of the stuff with software, that's your choice. But there are no requirement to software as such. -- 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 wb6bnq at cox.net Tue Aug 19 13:49:22 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Tue, 19 Aug 2008 10:49:22 -0700 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist... References: <8CAD029F1D74F52-1530-4B6@mblk-d45.sysops.aol.com> Message-ID: <48AB07A2.D1795BCC@cox.net> Hello Russ, Well, depending upon the size requirement of the thermal switch, I would consider trying to retro-fit. One company that makes such things is TEMPCO [ [1]http://www.tempco.com ]. They have several different kinds and even one model that is adjustable. There is a nice pictorial short-form PDF catalog that gives a clear picture of their temperature switches. Here is the URL for that : [2]http://www.tempco.com/Intro2008small.pdf See the 31st page. No doubt there are other manufacturers but this is the only one that comes to mind at the moment. As for #1 or #2 questions, I would think of those as a last ditch effort. Bill....WB6BNQ wa3frp at aol.com wrote: I am in the last stage of restoring a 1964 General Radio Frequency Standard Model 1120-AB. I'm having trouble getting the inner oven to work propoerly and the problem has been traced to a defective thermostat in the inner oven. In checking, the thermostat is a thermoswitch manufactured by Princo and is no longer available. My options appear to be: 1. locate a working GR Standard Frequency Oscillator (1113-A) and replace the entire chassis. 2. locate a non-working GR Frequency Oscillator and part it out as needed 3. find a suitable replacement for the original thermoswitch (78 C - closes circuit when temperature is reached) I was wondering if anyone on this list has any sources or leads for #1 and #2 and any opinions on a source for #3. Thanks Russ WA3FRP _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [3]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.tempco.com/ 2. http://www.tempco.com/Intro2008small.pdf 3. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From holrum at hotmail.com Tue Aug 19 13:54:12 2008 From: holrum at hotmail.com (Mark Sims) Date: Tue, 19 Aug 2008 17:54:12 +0000 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need In-Reply-To: References: Message-ID: The original thermoswitch sounds like is is a mechanical switch, so it can't be all that accurate or stable. I would use something like one of those TO-92 temperature sensor chips. I would probably use a 8 pin micro with an A/D to read it and drive a reed relay (or transistor). Analog people would use a comparator and voltage reference chip/pot. ---------------------------------------- _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 From wb6bnq at cox.net Tue Aug 19 13:58:30 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Tue, 19 Aug 2008 10:58:30 -0700 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need References: Message-ID: <48AB09C6.D9E9C2A9@cox.net> Mark, I think you missed the point ! He was not necessarily trying to use it as a frequency standard. He said he was trying to RESTORE it, including making it work ! Bill....WB6BNQ Mark Sims wrote: The original thermoswitch sounds like is is a mechanical switch, so it can't be all that accurate or stable. I would use something like one of those TO-92 temperature sensor chips. I would probably use a 8 pin micro with an A/D to read it and drive a reed relay (or transistor). Analog people would use a comparator and voltage reference chip/pot. ---------------------------------------- _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. [1]http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082 008 _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From wb6bnq at cox.net Tue Aug 19 14:06:56 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Tue, 19 Aug 2008 11:06:56 -0700 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Needassist... References: <8CAD029F1D74F52-1530-4B6@mblk-d45.sysops.aol.com> <48AB07A2.D1795BCC@cox.net> Message-ID: <48AB0BC0.31EFCBD7@cox.net> Russ, Here is the actual catalog PDF page [1]http://www.tempco.com/Catalog/Section%2013-pdf/Surface_Mount_Thermos tats.pdf Their site sucks for navigation and is very unclear, at first blush, on how to get to the meat. But I finally did find it. The above link has all the data on the variable model and the one I was thinking of (second item) which is the surface mount model. Bill....WB6BNQ Bill WB6BNQ wrote: Hello Russ, Well, depending upon the size requirement of the thermal switch, I would consider trying to retro-fit. One company that makes such things is TEMPCO [ [1][2]http://www.tempco.com ]. They have several different kinds and even one model that is adjustable. There is a nice pictorial short-form PDF catalog that gives a clear picture of their temperature switches. Here is the URL for that : [2][3]http://www.tempco.com/Intro2008small.pdf See the 31st page. No doubt there are other manufacturers but this is the only one that comes to mind at the moment. As for #1 or #2 questions, I would think of those as a last ditch effort. Bill....WB6BNQ wa3frp at aol.com wrote: I am in the last stage of restoring a 1964 General Radio Frequency Standard Model 1120-AB. I'm having trouble getting the inner oven to work propoerly and the problem has been traced to a defective thermostat in the inner oven. In checking, the thermostat is a thermoswitch manufactured by Princo and is no longer available. My options appear to be: 1. locate a working GR Standard Frequency Oscillator (1113-A) and replace the entire chassis. 2. locate a non-working GR Frequency Oscillator and part it out as needed 3. find a suitable replacement for the original thermoswitch (78 C - closes circuit when temperature is reached) I was wondering if anyone on this list has any sources or leads for #1 and #2 and any opinions on a source for #3. Thanks Russ WA3FRP _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [3][4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. [5]http://www.tempco.com/ 2. [6]http://www.tempco.com/Intro2008small.pdf 3. [7]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [8]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.tempco.com/Catalog/Section%2013-pdf/Surface_Mount_Thermostats.pdf 2. http://www.tempco.com/ 3. http://www.tempco.com/Intro2008small.pdf 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 5. http://www.tempco.com/ 6. http://www.tempco.com/Intro2008small.pdf 7. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 8. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From technoid_tim at comcast.net Tue Aug 19 14:09:37 2008 From: technoid_tim at comcast.net (Tim Schulz) Date: Tue, 19 Aug 2008 12:09:37 -0600 Subject: [time-nuts] HP 5062C service manual, schematics, or power supply troubleshooting tips Message-ID: <48AB0C61.1090106@comcast.net> Greetings, I am new to the list - I have an HP5062C Cesium Beam standard whose 18v power supply has died. I pulled the 18v regulator board out and it's pretty discolored from running hot. I don't know if there is a short on the 18v bus that caused the failure, or if its the regulator board itself. I have done lots of internet searches but have not found a service manual for sale yet, only the HP Journal issue on the standard. I do have the operations manual in PDF form. Many thanks, Tim Schulz... From wb6bnq at cox.net Tue Aug 19 14:42:40 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Tue, 19 Aug 2008 11:42:40 -0700 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Needassist... References: <8CAD029F1D74F52-1530-4B6@mblk-d45.sysops.aol.com> <48AB07A2.D1795BCC@cox.net> Message-ID: <48AB1420.1AD9D37B@cox.net> Russ, Here is another company that has several models of bi-metal TEMPCO type switches. Including some very small ones in either a dip (6600 series) or TO-220 style (6700 series). [1]http://www.airpax.net/site/sensing/bimetal/index.html To make Mark happy, if you google various combinations including "solid state" you will see some listings for solid state items but I have not checked them. I probably would not go overboard in trying to retro-fit with some solid state overkill because I don't think it will achieve good enough results. Besides it would not be a proper restoration at that point. Bill....WB6BNQ WB6BNQ wrote: Hello Russ, Well, depending upon the size requirement of the thermal switch, I would consider trying to retro-fit. One company that makes such things is TEMPCO [ [1][2]http://www.tempco.com ]. They have several different kinds and even one model that is adjustable. There is a nice pictorial short-form PDF catalog that gives a clear picture of their temperature switches. Here is the URL for that : [2][3]http://www.tempco.com/Intro2008small.pdf See the 31st page. No doubt there are other manufacturers but this is the only one that comes to mind at the moment. As for #1 or #2 questions, I would think of those as a last ditch effort. Bill....WB6BNQ wa3frp at aol.com wrote: I am in the last stage of restoring a 1964 General Radio Frequency Standard Model 1120-AB. I'm having trouble getting the inner oven to work propoerly and the problem has been traced to a defective thermostat in the inner oven. In checking, the thermostat is a thermoswitch manufactured by Princo and is no longer available. My options appear to be: 1. locate a working GR Standard Frequency Oscillator (1113-A) and replace the entire chassis. 2. locate a non-working GR Frequency Oscillator and part it out as needed 3. find a suitable replacement for the original thermoswitch (78 C - closes circuit when temperature is reached) I was wondering if anyone on this list has any sources or leads for #1 and #2 and any opinions on a source for #3. Thanks Russ WA3FRP _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [3][4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. [5]http://www.tempco.com/ 2. [6]http://www.tempco.com/Intro2008small.pdf 3. [7]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [8]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.airpax.net/site/sensing/bimetal/index.html 2. http://www.tempco.com/ 3. http://www.tempco.com/Intro2008small.pdf 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 5. http://www.tempco.com/ 6. http://www.tempco.com/Intro2008small.pdf 7. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 8. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From magnus at rubidium.dyndns.org Tue Aug 19 15:13:52 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Tue, 19 Aug 2008 21:13:52 +0200 Subject: [time-nuts] CE Mark In-Reply-To: <62180.1219165712@critter.freebsd.dk> References: <62180.1219165712@critter.freebsd.dk> Message-ID: <48AB1B70.20002@rubidium.dyndns.org> Poul-Henning Kamp wrote: > In message , "Ma > gnus Danielson" writes: >>> In message <001701c901d4$6ae978b0$0300a8c0 at pc52>, "Tom Van Baak" writes: >>> >>>> Is software covered by CE regulations, or just hardware? >>> Just hardware. >> Wrong. See my other notice. > > I hate to nitpick you, but there are no requirements to software > anywhere, only to the resulting products behaviour. If you do > some of the stuff with software, that's your choice. > > But there are no requirement to software as such. > I agree, but the point is that software is included in the product and its operation and cannot be separated from it. If it is configuration, software, firmware, hardware or mechanics does not really make much difference. If it triggers a behavour which breaks whatever rules and regulation there is, the products breaks it. If you alter the behaviour, be it configuration, software, firmware, hardware or mechanics in such a way that you break the regulation the products breaks it. How the part of the product is implemented is irrelevant. So, the separation between software and hardware is meaningless. Software can be an issue. Thus, saying only hardware matters is wrong. For most cases software is not much of an issue, but it can be an issue and it can be the cause of breaking the regulations for FCC or CE marks. To cover this point, there is no requirements specific to implementation. The rules must be black box oriented. So if we invent another implementation method the rules still applies. Cheers, Magnus From ed_palmer at sasktel.net Tue Aug 19 16:00:22 2008 From: ed_palmer at sasktel.net (Ed Palmer) Date: Tue, 19 Aug 2008 14:00:22 -0600 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist... In-Reply-To: References: Message-ID: <48AB2656.2060604@sasktel.net> Russ, I don't know what your requirements are for current capacity or mounting, but you might be able to find a simple crystal oven that you could rob the thermoswitch from. There are various ones on ebay that are 75 C. With luck, you might find an adjustable one that you could tweak to 78 C. Another thought is to replace the switch with a simple solid-state circuit. Since you'd be replacing an on-off switch, something like a thermistor + comparator would be appropriate Even if you were trying to do a 'return to original state' restoration, at least it would allow you to have a working system while you wait for something better to show up. Ed > Date: Tue, 19 Aug 2008 11:46:56 -0400 > From: wa3frp at aol.com > Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need > assist... > To: time-nuts at febo.com > Message-ID: <8CAD029F1D74F52-1530-4B6 at mblk-d45.sysops.aol.com> > Content-Type: text/plain; charset="us-ascii"; format=flowed > > > I am in the last stage of restoring a 1964 General Radio Frequency > Standard Model 1120-AB. > > I'm having trouble getting the inner oven to work propoerly and the > problem has been traced to a defective thermostat in the inner oven. > In checking, the thermostat is a thermoswitch manufactured by Princo > and is no longer available. > > My options appear to be: > > 1. locate a working GR Standard Frequency Oscillator (1113-A) and > replace the entire chassis. > > 2. locate a non-working GR Frequency Oscillator and part it out as > needed > > 3. find a suitable replacement for the original thermoswitch (78 C - > closes circuit when temperature is reached) > > > I was wondering if anyone on this list has any sources or leads for #1 > and #2 and any opinions on a source for #3. > > Thanks > Russ WA3FRP > From daun at yeagley.net Tue Aug 19 16:57:55 2008 From: daun at yeagley.net (Daun Yeagley) Date: Tue, 19 Aug 2008 16:57:55 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday Message-ID: <011401c9023e$413cc7a0$0c00a8c0@daundell> Looks like a little "OOPS" here! Daun Sent: Tuesday, August 19, 2008 4:43 PM Subject: FW: IIMorrow GPS units non-functional since Sunday Oops.... ________________________________ Sent: Tue 8/19/2008 4:10 PM To: grumman-gang at mailman.xmission.com Subject: IIMorrow GPS units non-functional since Sunday So I jump in my little bird yesterday for a 320 nm hop to a customer location, and find my GPS just can't get a fix on my position (Flybuddy 820, Apollo 360). While a little irritated by this fact, it isn't a critical piece of a equipment so I flip the power switch off and navigate via VOR, which delivered me safely and efficiently there and back. I head back out to the field today to see if I can troubleshoot the issue (armed with my manual), and find the thing can't keep track of the time. I set the time and a little while later it thinks it's Jan 3, 2089 (right time of day however). After my tinkering, I call the support line thinking I have a dead internal battery or something similar. It turns out every one of these units stopped working sometime Sunday and they don't fully understand the cause or the fix as of yet. Good news, I don't have a malfunctioning unit. Bad news, it's a brick until something changes and I get to look at 2 INOP stickers. They are working with the engineering group that provided the GPS engine for these units , and asked that I give them a few days and check back on the progress. If you have one of these units, expect it isn't functional. I will share any news I get. Scott Hjermstad From cdelect at juno.com Tue Aug 19 17:09:21 2008 From: cdelect at juno.com (corby d dawson) Date: Tue, 19 Aug 2008 14:09:21 -0700 Subject: [time-nuts] 5062C power supply problem Message-ID: <20080819.140923.-558537.5.cdelect@juno.com> Tim, You need to make sure the ion pump current has dropped to <10 on the meter or else the +18V supply is disabled. If it is high watch the 18 volt meter position and momentarily remove the A7 high voltage by pulling out the HV connector. If the +18 comes up then reconnect the HV and let the unit run a couple days. Hopefully you should see the ion pump current slowly drop, when it falls below the trip point the CS oven and +18V will come on and the ion pump reading will rise again, possibly pegging. This is normal for a unit that has been off for a long while. It can take a couple days of cycling to finally drop and stay below the trip point. If the +18 is indeed dead then you can hook an external +18V @ 1.5A between chassis ground and one of the marked +18V runs. Current draw is about 1.3A. This is just for momentary testing as the ion pump interlock will be bypassed. If you are patient you can apply the +18V, watch the ion pump peg, remove the +18V, wait till the ion pump drops below 10, and repeat until you can leave the +18V connected and the ion pump is 10 or below. I have done this while working on these units and also have replaced the +18V card with a DC to DC module that has remote gate capability so that the ion pump circuit will work with it. Hope this helps, Corby Dawson ____________________________________________________________ Need cash? Click to get a loan. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3mKiwGS8ET4aZc2MsHNNSQ9Rn560rX0SyLVQaeqyaBx7UTCp/ From hartzell at gmail.com Tue Aug 19 17:21:29 2008 From: hartzell at gmail.com (Dave hartzell) Date: Tue, 19 Aug 2008 14:21:29 -0700 Subject: [time-nuts] Looking for good texts on precision timing... Message-ID: <1c096fd70808191421s5d446a5bjcd35ed36cbfe295b@mail.gmail.com> Hello, I'm new to the high-accuracy timing arena, and I'm looking for good books or other information on the topic in general, preferably starting from Ground Zero. Any ideas? Thanks, Dave From dgcarlson at sbcglobal.net Tue Aug 19 17:33:11 2008 From: dgcarlson at sbcglobal.net (Dave 'SqueezeBox' Carlson) Date: Tue, 19 Aug 2008 14:33:11 -0700 Subject: [time-nuts] HP 5062C service manual, schematics, or power supply troubleshooting tips References: <48AB0C61.1090106@comcast.net> Message-ID: <002501c90243$2e6a69c0$8d08a8c0@symmetricom.com> very typical of the 5062C regulator board. IF run long enough, the PCB can actually de-laminate or crumble when removed. Run very hot and little circulation in the honey-comb structure. Dave ----- Original Message ----- From: "Tim Schulz" To: Sent: Tuesday, August 19, 2008 11:09 AM Subject: [time-nuts] HP 5062C service manual, schematics, or power supply troubleshooting tips Greetings, I am new to the list - I have an HP5062C Cesium Beam standard whose 18v power supply has died. I pulled the 18v regulator board out and it's pretty discolored from running hot. I don't know if there is a short on the 18v bus that caused the failure, or if its the regulator board itself. I have done lots of internet searches but have not found a service manual for sale yet, only the HP Journal issue on the standard. I do have the operations manual in PDF form. Many thanks, Tim Schulz... _______________________________________________ time-nuts mailing list -- 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 wa3frp at aol.com Tue Aug 19 17:55:37 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Tue, 19 Aug 2008 17:55:37 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need In-Reply-To: References: Message-ID: <8CAD05D7260D642-14EC-1F79@WEBMAIL-MC02.sysops.aol.com> Sorry for missing enough detail on the original thermoswitch. The original thermoswitch was a unique design that I have not seen elsewhere. The Princo thermoswitch was a modified mercury thermometer with two electrodes installed. When the temperature rises, the column of mercury comes into contact with both electrodes and completes the electric circuit. The inner oven stays within +/-0.05 degree C of 78C. Since the design involved a mercury thermometer, the form factor is 0.25 by 4.25 inches. -----Original Message----- From: Mark Sims To: time-nuts at febo.com Sent: Tue, 19 Aug 2008 1:54 pm Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need The original thermoswitch sounds like is is a mechanical switch, so it can't be all that accurate or stable. I would use something like one of those TO-92 temperature sensor chips. I would probably use a 8 pin micro with an A/D to read it and drive a reed relay (or transistor). Analog people would use a comparator and voltage reference chip/pot. ---------------------------------------- _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 _______________________________________________ time-nuts mailing list -- 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 wa3frp at aol.com Tue Aug 19 18:02:48 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Tue, 19 Aug 2008 18:02:48 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Needassist... In-Reply-To: <48AB0BC0.31EFCBD7@cox.net> References: <8CAD029F1D74F52-1530-4B6@mblk-d45.sysops.aol.com> <48AB07A2.D1795BCC@cox.net> <48AB0BC0.31EFCBD7@cox.net> Message-ID: <8CAD05E73633FC6-14EC-1FBF@WEBMAIL-MC02.sysops.aol.com> Hi Bill, The Tempco units look great. My original Google search came up with similar Fenwal units that are a bit larger sizewise. The size of the Tempco units appears to be a fit into the space reserved for the original thermoswitch. Thanks for the assist! 73 Russ WA3FRP -----Original Message----- From: WB6BNQ To: Discussion of precise time and frequency measurement Sent: Tue, 19 Aug 2008 2:06 pm Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard - Needassist... Russ, Here is the actual catalog PDF page [1]http://www.tempco.com/Catalog/Section%2013-pdf/Surface_Mount_Thermos tats.pdf Their site sucks for navigation and is very unclear, at first blush, on how to get to the meat. But I finally did find it. The above link has all the data on the variable model and the one I was thinking of (second item) which is the surface mount model. Bill....WB6BNQ Bill WB6BNQ wrote: Hello Russ, Well, depending upon the size requirement of the thermal switch, I would consider trying to retro-fit. One company that makes such things is TEMPCO [ [1][2]http://www.tempco.com ]. They have several different kinds and even one model that is adjustable. There is a nice pictorial short-form PDF catalog that gives a clear picture of their temperature switches. Here is the URL for that : [2][3]http://www.tempco.com/Intro2008small.pdf See the 31st page. No doubt there are other manufacturers but this is the only one that comes to mind at the moment. As for #1 or #2 questions, I would think of those as a last ditch effort. Bill....WB6BNQ wa3frp at aol.com wrote: I am in the last stage of restoring a 1964 General Radio Frequency Standard Model 1120-AB. I'm having trouble getting the inner oven to work propoerly and the problem has been traced to a defective thermostat in the inner oven. In checking, the thermostat is a thermoswitch manufactured by Princo and is no longer available. My options appear to be: 1. locate a working GR Standard Frequency Oscillator (1113-A) and replace the entire chassis. 2. locate a non-working GR Frequency Oscillator and part it out as needed 3. find a suitable replacement for the original thermoswitch (78 C - closes circuit when temperature is reached) I was wondering if anyone on this list has any sources or leads for #1 and #2 and any opinions on a source for #3. Thanks Russ WA3FRP _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [3][4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. [5]http://www.tempco.com/ 2. [6]http://www.tempco.com/Intro2008small.pdf 3. [7]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [8]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.tempco.com/Catalog/Section%2013-pdf/Surface_Mount_Thermostats.pdf 2. http://www.tempco.com/ 3. http://www.tempco.com/Intro2008small.pdf 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 5. http://www.tempco.com/ 6. http://www.tempco.com/Intro2008small.pdf 7. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 8. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list -- 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 Tue Aug 19 18:04:52 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Tue, 19 Aug 2008 15:04:52 -0700 Subject: [time-nuts] Looking for good texts on precision timing... References: <1c096fd70808191421s5d446a5bjcd35ed36cbfe295b@mail.gmail.com> Message-ID: <000b01c90247$9ba86dd0$0300a8c0@pc52> > Hello, > > I'm new to the high-accuracy timing arena, and I'm looking for good > books or other information on the topic in general, preferably > starting from Ground Zero. > > Any ideas? > > Thanks, > > Dave http://www.leapsecond.com/pages/books/ http://www.leapsecond.com/time-nuts.htm /tvb From hartzell at gmail.com Tue Aug 19 18:40:25 2008 From: hartzell at gmail.com (Dave hartzell) Date: Tue, 19 Aug 2008 15:40:25 -0700 Subject: [time-nuts] Looking for good texts on precision timing... In-Reply-To: <000b01c90247$9ba86dd0$0300a8c0@pc52> References: <1c096fd70808191421s5d446a5bjcd35ed36cbfe295b@mail.gmail.com> <000b01c90247$9ba86dd0$0300a8c0@pc52> Message-ID: <1c096fd70808191540p319bf629scc1cb28c2b4363ef@mail.gmail.com> >> I'm new to the high-accuracy timing arena, and I'm looking for good >> books or other information on the topic in general, preferably >> starting from Ground Zero. > http://www.leapsecond.com/pages/books/ > http://www.leapsecond.com/time-nuts.htm Thanks! From wa3frp at aol.com Tue Aug 19 18:45:02 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Tue, 19 Aug 2008 18:45:02 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist... In-Reply-To: <48AB2656.2060604@sasktel.net> References: <48AB2656.2060604@sasktel.net> Message-ID: <8CAD0645A41F3E9-1C14-18FF@FWM-M41.sysops.aol.com> Hi Ed, Thanks for your time and your great suggestion. At this point, I think that the suggestion to use the Tempco thermoswitch will be the best way to preserve the original design of the inner oven and easiest to reverse should an exact replacement Princo thermoswitch become available in the future. Best Regards, Russ -----Original Message----- From: Ed Palmer To: time-nuts at febo.com Sent: Tue, 19 Aug 2008 4:00 pm Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist... Russ, I don't know what your requirements are for current capacity or mounting, but you might be able to find a simple crystal oven that you could rob the thermoswitch from. There are various ones on ebay that are 75 C. With luck, you might find an adjustable one that you could tweak to 78 C. Another thought is to replace the switch with a simple solid-state circuit. Since you'd be replacing an on-off switch, something like a thermistor + comparator would be appropriate Even if you were trying to do a 'return to original state' restoration, at least it would allow you to have a working system while you wait for something better to show up. Ed > Date: Tue, 19 Aug 2008 11:46:56 -0400 > From: wa3frp at aol.com > Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need > assist... > To: time-nuts at febo.com > Message-ID: <8CAD029F1D74F52-1530-4B6 at mblk-d45.sysops.aol.com> > Content-Type: text/plain; charset="us-ascii"; format=flowed > > > I am in the last stage of restoring a 1964 General Radio Frequency > Standard Model 1120-AB. > > I'm having trouble getting the inner oven to work propoerly and the > problem has been traced to a defective thermostat in the inner oven. > In checking, the thermostat is a thermoswitch manufactured by Princo > and is no longer available. > > My options appear to be: > > 1. locate a working GR Standard Frequency Oscillator (1113-A) and > replace the entire chassis. > > 2. locate a non-working GR Frequency Oscillator and part it out as > needed > > 3. find a suitable replacement for the original thermoswitch (78 C - > closes circuit when temperature is reached) > > > I was wondering if anyone on this list has any sources or leads for #1 > and #2 and any opinions on a source for #3. > > Thanks > Russ WA3FRP > _______________________________________________ time-nuts mailing list -- 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 technoid_tim at comcast.net Tue Aug 19 19:08:13 2008 From: technoid_tim at comcast.net (Tim Schulz) Date: Tue, 19 Aug 2008 17:08:13 -0600 Subject: [time-nuts] HP 5062C service manual, schematics, or power supply troubleshooting tips In-Reply-To: <002501c90243$2e6a69c0$8d08a8c0@symmetricom.com> References: <48AB0C61.1090106@comcast.net> <002501c90243$2e6a69c0$8d08a8c0@symmetricom.com> Message-ID: <48AB525D.8030704@comcast.net> Hi Dave - thanks for the note. The plastic eject handle was completely brittle and fell apart on removal, but the PCB still seems pretty solid, I have seen worst from early ceramic decoupling cap failures. This probably means that there are lots of 5062s out there without 18v supplies. Are people adding fan cooling to their systems to extend the life of the hardware? tim Dave 'SqueezeBox' Carlson wrote: > very typical of the 5062C regulator board. IF run long enough, the PCB can > actually de-laminate or crumble when removed. Run very hot and little > circulation in the honey-comb structure. > > Dave > From holrum at hotmail.com Tue Aug 19 19:17:07 2008 From: holrum at hotmail.com (Mark Sims) Date: Tue, 19 Aug 2008 23:17:07 +0000 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: References: Message-ID: I suspect the only place you would find a replacement themoswitch is in another unit. I also doubt that any current mechanical switch will be anywhere near stable and accurate enough. I stand by my original comments: Built a solid state functional replacement in the same form factor as the original unit. It will be hidden inside the oven assembly where only you will know of the dastardly deed that you did. If you ever find a replacement switch, you can install it and bask in its originality. Until then, bask in its solid state patch enabled oscillatude. A non-original part that restores a device to operating condition is far superior to a dead unit... particularly if the part is not visible. There are lots of zillion dollar antique cars winning best-of-show with modern internal engine components (not to mention bondo and fiberglass under the paint). ---------------------------------------- _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From technoid_tim at comcast.net Tue Aug 19 19:17:14 2008 From: technoid_tim at comcast.net (Tim Schulz) Date: Tue, 19 Aug 2008 17:17:14 -0600 Subject: [time-nuts] time-nuts Digest, Vol 49, Issue 50 In-Reply-To: References: Message-ID: <48AB547A.4050707@comcast.net> Hi Corby - Thank you for the very helpful information. This 5062C had been operational for me for about 8 months before it died. It would occasionally loose it's green light, but when I went through the meter readings, I thought everything was nominal according to penciled in figures. It will be about a week before I can get back to it, but at least I have plenty of things to try. regards, tim > Date: Tue, 19 Aug 2008 14:09:21 -0700 > From: corby d dawson > Subject: Re: [time-nuts] 5062C power supply problem > To: time-nuts at febo.com > Message-ID: <20080819.140923.-558537.5.cdelect at juno.com> > Content-Type: text/plain; charset=us-ascii > > Tim, > > You need to make sure the ion pump current has dropped to <10 on the > meter or else the +18V supply is disabled. > > If it is high watch the 18 volt meter position and momentarily remove the > A7 high voltage by pulling out the HV connector. > > If the +18 comes up then reconnect the HV and let the unit run a couple > days. > > Hopefully you should see the ion pump current slowly drop, when it falls > below the trip point the CS oven and +18V will come on and the ion pump > reading will rise again, possibly pegging. > > This is normal for a unit that has been off for a long while. It can take > a couple days of cycling to finally drop and stay below the trip point. > > If the +18 is indeed dead then you can hook an external +18V @ 1.5A > between chassis ground and one of the marked +18V runs. > > Current draw is about 1.3A. > > This is just for momentary testing as the ion pump interlock will be > bypassed. If you are patient you can apply the +18V, watch the ion pump > peg, remove the +18V, wait till the ion pump drops below 10, and repeat > until you can leave the +18V connected and the ion pump is 10 or below. > > I have done this while working on these units and also have replaced the > +18V card with a DC to DC module that has remote gate capability so that > the ion pump circuit will work with it. > > Hope this helps, > > Corby Dawson > From namichie at gmail.com Tue Aug 19 19:46:14 2008 From: namichie at gmail.com (Neville Michie) Date: Wed, 20 Aug 2008 09:46:14 +1000 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: References: Message-ID: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> Hi, this is a second attempt at an answer, the first seemed to evaporate. Mercury-in -glass thermometers have formed the basis of a system of thermostats used constant temperature systems of very high performance. A major producer of contact thermometers was Jumo (maybe German). These thermometers had a thin wire that went down the capillary and contacted the mercury at the set temperature. The system could be accurate to 0.005 degree. The control algorithm is alien to modern EEs but used a large thermal mass and a fixed rate of heating to produce a slow temperature ramp. Fast response by the thermometer switching kept overshoot down to millidegrees. A cycle time of 5 or 10 seconds kept a very low amplitude temperature ramp running up and down with mean temperature held quite close. Locating the thermometer close to the heater caused a little over control which reduced overshoot and cycle amplitude. The thermometers had up to 30 mA run through the wire, but more modern units reduced this to 1mA. If the tip is corroded on your thermometer contact, maybe a higher resistance measuring circuit may still operate reliably. Good Luck with the unit, Neville Michie On 20/08/2008, at 9:17 AM, Mark Sims wrote: > > I suspect the only place you would find a replacement themoswitch > is in another unit. I also doubt that any current mechanical > switch will be anywhere near stable and accurate enough. > > I stand by my original comments: Built a solid state functional > replacement in the same form factor as the original unit. It will > be hidden inside the oven assembly where only you will know of the > dastardly deed that you did. If you ever find a replacement > switch, you can install it and bask in its originality. Until > then, bask in its solid state patch enabled oscillatude. > > A non-original part that restores a device to operating condition > is far superior to a dead unit... particularly if the part is not > visible. There are lots of zillion dollar antique cars winning > best-of-show with modern internal engine components (not to mention > bondo and fiberglass under the paint). > ---------------------------------------- > > _________________________________________________________________ > Be the filmmaker you always wanted to be?learn how to burn a DVD > with Windows?. > http://clk.atdmt.com/MRT/go/108588797/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 jim77742 at gmail.com Tue Aug 19 20:57:55 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 20 Aug 2008 10:57:55 +1000 Subject: [time-nuts] I've settled on a micro-controller Message-ID: Folks, Thanks for all your advice, not to mention personal emails as well. After reading the advice here and info on the net elsewhere I've settled on AVR. As I stated, being a very experienced software developer, C was important to me and also as I get to grips with the micro controller experience, some ability to produce larger and larger projects which the AVR range certainly provides. The were some other great ideas suggested but weighing everything up I think this is the right path for me. As a development board I nearly went with the mega-donkey (looks good Mark), but I thought I'd start with something smaller first. I chose this: http://microcontrollershop.com/product_info.php?products_id=2374&osCsid=e0d493c4233a8005180aad018d1d5bd6 which for $99 seems excellent value. Whilst I don't need the C training provided, I liked the look of the course for teaching all aspects of the AVR micro controllers. I'll be sure to provide feedback down the track on my decision. :-) Thanks again all, Regards, Jim From jim77742 at gmail.com Tue Aug 19 21:01:14 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 20 Aug 2008 11:01:14 +1000 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: <011401c9023e$413cc7a0$0c00a8c0@daundell> References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: I'm fascinated by the 320 nm flight. 320 billionths of a metre is quite short distance to use a plane. I would have walked. Jim 2008/8/20 Daun Yeagley > Looks like a little "OOPS" here! > > Daun > > > Sent: Tuesday, August 19, 2008 4:43 PM > Subject: FW: IIMorrow GPS units non-functional since Sunday > > > > Oops.... > > ________________________________ > > Sent: Tue 8/19/2008 4:10 PM > To: grumman-gang at mailman.xmission.com > Subject: IIMorrow GPS units non-functional since Sunday > > > > So I jump in my little bird yesterday for a 320 nm hop to a customer > location, and find my GPS just can't get a fix on my position (Flybuddy > 820, > Apollo 360). While a little irritated by this fact, it isn't a critical > piece of a equipment so I flip the power switch off and navigate via VOR, > which delivered me safely and efficiently there and back. > > > > I head back out to the field today to see if I can troubleshoot the issue > (armed with my manual), and find the thing can't keep track of the time. I > set the time and a little while later it thinks it's Jan 3, 2089 (right > time > of day however). After my tinkering, I call the support line thinking I > have a dead internal battery or something similar. > > > > It turns out every one of these units stopped working sometime Sunday and > they don't fully understand the cause or the fix as of yet. Good news, I > don't have a malfunctioning unit. Bad news, it's a brick until something > changes and I get to look at 2 INOP stickers. > > > > They are working with the engineering group that provided the GPS engine > for > these units , and asked that I give them a few days and check back on the > progress. If you have one of these units, expect it isn't functional. I > will share any news I get. > > > > Scott Hjermstad > > > > > > > _______________________________________________ > time-nuts mailing list -- 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 daun at yeagley.net Tue Aug 19 21:09:32 2008 From: daun at yeagley.net (Daun Yeagley) Date: Tue, 19 Aug 2008 21:09:32 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: <013c01c90261$6811f3a0$0c00a8c0@daundell> You must not be an aviator. try "nautical mile". ;-) Of course you probably are referring to "NM". Have to watch out with this group! Daun -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Jim Palfreyman Sent: Tuesday, August 19, 2008 9:01 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday I'm fascinated by the 320 nm flight. 320 billionths of a metre is quite short distance to use a plane. I would have walked. Jim 2008/8/20 Daun Yeagley > Looks like a little "OOPS" here! > > Daun > > > Sent: Tuesday, August 19, 2008 4:43 PM > Subject: FW: IIMorrow GPS units non-functional since Sunday > > > > Oops.... > > ________________________________ > > Sent: Tue 8/19/2008 4:10 PM > To: grumman-gang at mailman.xmission.com > Subject: IIMorrow GPS units non-functional since Sunday > > > > So I jump in my little bird yesterday for a 320 nm hop to a customer > location, and find my GPS just can't get a fix on my position > (Flybuddy 820, Apollo 360). While a little irritated by this fact, it > isn't a critical piece of a equipment so I flip the power switch off > and navigate via VOR, which delivered me safely and efficiently there > and back. > > > > I head back out to the field today to see if I can troubleshoot the > issue (armed with my manual), and find the thing can't keep track of > the time. I set the time and a little while later it thinks it's Jan > 3, 2089 (right time > of day however). After my tinkering, I call the support line thinking I > have a dead internal battery or something similar. > > > > It turns out every one of these units stopped working sometime Sunday > and they don't fully understand the cause or the fix as of yet. Good > news, I don't have a malfunctioning unit. Bad news, it's a brick > until something changes and I get to look at 2 INOP stickers. > > > > They are working with the engineering group that provided the GPS > engine for these units , and asked that I give them a few days and > check back on the > progress. If you have one of these units, expect it isn't functional. I > will share any news I get. > > > > Scott Hjermstad > > > > > > > _______________________________________________ > time-nuts mailing list -- 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 XDE-L2G3 at myamail.com Tue Aug 19 21:26:55 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Tue, 19 Aug 2008 21:26:55 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: "Jim Palfreyman" wrote: > >I'm fascinated by the 320 nm flight. > >320 billionths of a metre is quite short distance to use a plane. > >I would have walked. > >Jim LOL! Boats and planes use nautical miles (nm). From wikipedia, one nm is approximately one minute of latitude along any meridian. The abbreviation nm, though conflicting with the SI symbol for the nanometre, is also in widespread use. so you have to look at the context. In this example, 320 nautical miles = 368.2 miles = 592.64 kilometers. A nice flight in good weather, but it can be a bear in IFR with known ice. Either way, this is the way to do it: http://www.jetphotos.net/viewphoto.php?id=5874208&nseq=0 (This was my first plane. And the best one I have ever owned!) Regards, Mike Monett From fortime at bellsouth.net Tue Aug 19 21:33:57 2008 From: fortime at bellsouth.net (phil) Date: Tue, 19 Aug 2008 21:33:57 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> Message-ID: <001401c90264$d13d2400$a101a8c0@officemail> Neville, good answer. Perhaps the original poster could supply a photo of his switch, perhaps more suggestions could be made. I think we had an old gr-1100 at one time, it was a 100kc unit. Needless to say it was scrapped years ago and I'm sure it's been melted down and sent back to the usa in tin cans or cars by now! I'm curious as to how the switch failed. I'm assuming it was a sealed unit. Phil ----- Original Message ----- From: "Neville Michie" To: "Discussion of precise time and frequency measurement" Sent: Tuesday, August 19, 2008 7:46 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard Hi, this is a second attempt at an answer, the first seemed to evaporate. Mercury-in -glass thermometers have formed the basis of a system of thermostats used constant temperature systems of very high performance. A major producer of contact thermometers was Jumo (maybe German). These thermometers had a thin wire that went down the capillary and contacted the mercury at the set temperature. The system could be accurate to 0.005 degree. The control algorithm is alien to modern EEs but used a large thermal mass and a fixed rate of heating to produce a slow temperature ramp. Fast response by the thermometer switching kept overshoot down to millidegrees. A cycle time of 5 or 10 seconds kept a very low amplitude temperature ramp running up and down with mean temperature held quite close. Locating the thermometer close to the heater caused a little over control which reduced overshoot and cycle amplitude. The thermometers had up to 30 mA run through the wire, but more modern units reduced this to 1mA. If the tip is corroded on your thermometer contact, maybe a higher resistance measuring circuit may still operate reliably. Good Luck with the unit, Neville Michie On 20/08/2008, at 9:17 AM, Mark Sims wrote: > > I suspect the only place you would find a replacement themoswitch > is in another unit. I also doubt that any current mechanical > switch will be anywhere near stable and accurate enough. > > I stand by my original comments: Built a solid state functional > replacement in the same form factor as the original unit. It will > be hidden inside the oven assembly where only you will know of the > dastardly deed that you did. If you ever find a replacement > switch, you can install it and bask in its originality. Until > then, bask in its solid state patch enabled oscillatude. > > A non-original part that restores a device to operating condition > is far superior to a dead unit... particularly if the part is not > visible. There are lots of zillion dollar antique cars winning > best-of-show with modern internal engine components (not to mention > bondo and fiberglass under the paint). > ---------------------------------------- > > _________________________________________________________________ > Be the filmmaker you always wanted to be?learn how to burn a DVD > with Windows?. > http://clk.atdmt.com/MRT/go/108588797/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 max at maxsmusicplace.com Tue Aug 19 21:50:59 2008 From: max at maxsmusicplace.com (Max Robinson) Date: Tue, 19 Aug 2008 20:50:59 -0500 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need References: <8CAD05D7260D642-14EC-1F79@WEBMAIL-MC02.sysops.aol.com> Message-ID: <00c501c90267$31d1cd50$6401a8c0@BACKROOM> The same thermostat was used in the GR 1113-A which I have one of. That may lead you to another source for a replacement. 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: To: Cc: Sent: Tuesday, August 19, 2008 4:55 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need > Sorry for missing enough detail on the original thermoswitch. > > The original thermoswitch was a unique design that I have not seen > elsewhere. The Princo thermoswitch was a modified mercury thermometer > with two electrodes installed. When the temperature rises, the column > of mercury comes into contact with both electrodes and completes the > electric circuit. The inner oven stays within +/-0.05 degree C of 78C. > > Since the design involved a mercury thermometer, the form factor is > 0.25 by 4.25 inches. > > > > > -----Original Message----- > From: Mark Sims > To: time-nuts at febo.com > Sent: Tue, 19 Aug 2008 1:54 pm > Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need > > > > The original thermoswitch sounds like is is a mechanical switch, so it > can't be > all that accurate or stable. > > I would use something like one of those TO-92 temperature sensor chips. > I would > probably use a 8 pin micro with an A/D to read it and drive a reed > relay (or > transistor). Analog people would use a comparator and voltage > reference > chip/pot. > ---------------------------------------- > > _________________________________________________________________ > See what people are saying about Windows Live. Check out featured > posts. > http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 > _______________________________________________ > time-nuts mailing list -- 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 ka2cdk at cox.net Wed Aug 20 01:44:45 2008 From: ka2cdk at cox.net (Thomas A. Frank) Date: Wed, 20 Aug 2008 01:44:45 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: <011401c9023e$413cc7a0$0c00a8c0@daundell> References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: > It turns out every one of these units stopped working sometime > Sunday and > they don't fully understand the cause or the fix as of yet. Good > news, I > don't have a malfunctioning unit. Funny, but to me, having the thing stop working qualifies as "malfunctioning". Just a thought. Tom Frank, KA2CDK From fortime at bellsouth.net Wed Aug 20 02:15:44 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 02:15:44 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: <000c01c9028c$2e321180$a101a8c0@officemail> ----- Original Message ----- From: "Thomas A. Frank" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, August 20, 2008 1:44 AM Subject: Re: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday >> It turns out every one of these units stopped working sometime >> Sunday and >> they don't fully understand the cause or the fix as of yet. Good >> news, I >> don't have a malfunctioning unit. > > Funny, but to me, having the thing stop working qualifies as > "malfunctioning". > > Just a thought. > > Tom Frank, KA2CDK > "malfunctioning"? Can it be said, if you have a task that you are being paid big bucks an hour to perform, and have to stop in the middle to go the little boys room that you are "malfunctioning"? A firmware update is a heck of a lot better than a "blown up" unit. We have a bunch of various brand and model gps units (time, frequency standards etc.) and several we were required to update firmware over the years. Still going strong after their malfunction or update. From magnus at rubidium.dyndns.org Wed Aug 20 02:16:29 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 20 Aug 2008 08:16:29 +0200 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: <011401c9023e$413cc7a0$0c00a8c0@daundell> References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: <48ABB6BD.9070008@rubidium.dyndns.org> > So I jump in my little bird yesterday for a 320 nm hop to a customer > location, and find my GPS just can't get a fix on my position (Flybuddy 820, > Apollo 360). While a little irritated by this fact, it isn't a critical > piece of a equipment so I flip the power switch off and navigate via VOR, > which delivered me safely and efficiently there and back. > > I head back out to the field today to see if I can troubleshoot the issue > (armed with my manual), and find the thing can't keep track of the time. I > set the time and a little while later it thinks it's Jan 3, 2089 (right time > of day however). After my tinkering, I call the support line thinking I > have a dead internal battery or something similar. > > It turns out every one of these units stopped working sometime Sunday and > they don't fully understand the cause or the fix as of yet. Good news, I > don't have a malfunctioning unit. Bad news, it's a brick until something > changes and I get to look at 2 INOP stickers. > > They are working with the engineering group that provided the GPS engine for > these units , and asked that I give them a few days and check back on the > progress. If you have one of these units, expect it isn't functional. I > will share any news I get. This is not a that supprising thing really. Various bugs and limits in receivers creep up regularly. Commercial airlines have lost GPS tracking while in flight over the USA. The vendor has, to my knowledge, still not upgraded the software even if this was a few years back. In this case, 4 extra 1024 week rollovers gets you in the neighborhood (+79 years). It is infact exactly 4194 weeks wrong. It occured after exactly 1494 weeks. I think someone has a bug in the week roll-over mechanism. Cheers, Magnus From jim77742 at gmail.com Wed Aug 20 02:24:31 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 20 Aug 2008 16:24:31 +1000 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: Wow. Don't tell me people still use miles? Nautical or otherwise? What's wrong with the good old kilometre? Jim 2008/8/20 Mike Monett > "Jim Palfreyman" wrote: > > > >I'm fascinated by the 320 nm flight. > > > >320 billionths of a metre is quite short distance to use a plane. > > > >I would have walked. > > > >Jim > > LOL! > > Boats and planes use nautical miles (nm). From wikipedia, one nm is > approximately one minute of latitude along any meridian. The abbreviation > nm, though conflicting with the SI symbol for the nanometre, is also in > widespread use. so you have to look at the context. > > In this example, 320 nautical miles = 368.2 miles = 592.64 kilometers. A > nice flight in good weather, but it can be a bear in IFR with known ice. > Either way, this is the way to do it: > > http://www.jetphotos.net/viewphoto.php?id=5874208&nseq=0 > > (This was my first plane. And the best one I have ever owned!) > > Regards, > > Mike Monett > > _______________________________________________ > time-nuts mailing list -- 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 fortime at bellsouth.net Wed Aug 20 02:25:53 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 02:25:53 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday References: <011401c9023e$413cc7a0$0c00a8c0@daundell> <000c01c9028c$2e321180$a101a8c0@officemail> Message-ID: <001501c9028d$99b59bb0$a101a8c0@officemail> ----- Original Message ----- From: "phil" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, August 20, 2008 2:15 AM Subject: Re: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday > > ----- Original Message ----- > From: "Thomas A. Frank" > To: "Discussion of precise time and frequency measurement" > > Sent: Wednesday, August 20, 2008 1:44 AM > Subject: Re: [time-nuts] FW: IIMorrow GPS units non-functional since > Sunday > > >>> It turns out every one of these units stopped working sometime >>> Sunday and >>> they don't fully understand the cause or the fix as of yet. Good >>> news, I >>> don't have a malfunctioning unit. >> >> Funny, but to me, having the thing stop working qualifies as >> "malfunctioning". >> >> Just a thought. >> >> Tom Frank, KA2CDK >> > > "malfunctioning"? > Can it be said, if you have a task that you are being paid big bucks an > hour > to perform, and have to stop in the middle to go the little boys room that > you are "malfunctioning"? > > A firmware update is a heck of a lot better than a "blown up" unit. > We have a bunch of various brand and model gps units (time, frequency > standards etc.) and several we were required to update firmware over the > years. Still going strong after their malfunction or update. > Tom, sorry, no offence meant. I just couldn't resist interpreting your statement literally where you said: "but to me, having the thing stop working qualifies as "malfunctioning". Phil From wa3frp at aol.com Wed Aug 20 02:34:18 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Wed, 20 Aug 2008 02:34:18 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <001401c90264$d13d2400$a101a8c0@officemail> References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> Message-ID: <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> Phil, The details of the thermoswitch failure are not completely clear. Intermittently, the mercury column will pass the 78C point without causing circuit closure. Instead, a pulsating open / close with an internal resistance of 50K - 300K is observed. Circuit closure eventually happens at a temperature above 82C. Once an external failure, i.e. lead wiring, was ruled out, I used a borrowed microscope to view the internal structure of the thermoswitch. Unfortunately, this did not reveal the failure source. Russ -----Original Message----- From: phil To: Discussion of precise time and frequency measurement Sent: Tue, 19 Aug 2008 9:33 pm Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard Neville, good answer. Perhaps the original poster could supply a photo of his switch, perhaps more suggestions could be made. I think we had an old gr-1100 at one time, it was a 100kc unit. Needless to say it was scrapped years ago and I'm sure it's been melted down and sent back to the usa in tin cans or cars by now! I'm curious as to how the switch failed. I'm assuming it was a sealed unit. Phil ----- Original Message ----- From: "Neville Michie" To: "Discussion of precise time and frequency measurement" Sent: Tuesday, August 19, 2008 7:46 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard Hi, this is a second attempt at an answer, the first seemed to evaporate. Mercury-in -glass thermometers have formed the basis of a system of thermostats used constant temperature systems of very high performance. A major producer of contact thermometers was Jumo (maybe German). These thermometers had a thin wire that went down the capillary and contacted the mercury at the set temperature. The system could be accurate to 0.005 degree. The control algorithm is alien to modern EEs but used a large thermal mass and a fixed rate of heating to produce a slow temperature ramp. Fast response by the thermometer switching kept overshoot down to millidegrees. A cycle time of 5 or 10 seconds kept a very low amplitude temperature ramp running up and down with mean temperature held quite close. Locating the thermometer close to the heater caused a little over control which reduced overshoot and cycle amplitude. The thermometers had up to 30 mA run through the wire, but more modern units reduced this to 1mA. If the tip is corroded on your thermometer contact, maybe a higher resistance measuring circuit may still operate reliably. Good Luck with the unit, Neville Michie On 20/08/2008, at 9:17 AM, Mark Sims wrote: > > I suspect the only place you would find a replacement themoswitch > is in another unit. I also doubt that any current mechanical > switch will be anywhere near stable and accurate enough. > > I stand by my original comments: Built a solid state functional > replacement in the same form factor as the original unit. It will > be hidden inside the oven assembly where only you will know of the > dastardly deed that you did. If you ever find a replacement > switch, you can install it and bask in its originality. Until > then, bask in its solid state patch enabled oscillatude. > > A non-original part that restores a device to operating condition > is far superior to a dead unit... particularly if the part is not > visible. There are lots of zillion dollar antique cars winning > best-of-show with modern internal engine components (not to mention > bondo and fiberglass under the paint). > ---------------------------------------- > > _________________________________________________________________ > Be the filmmaker you always wanted to beearn how to burn a DVD > with Windows. > http://clk.atdmt.com/MRT/go/108588797/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 wa3frp at aol.com Wed Aug 20 02:34:28 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Wed, 20 Aug 2008 02:34:28 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> Message-ID: <8CAD0A5EE00C90B-794-223B@WEBMAIL-MB15.sysops.aol.com> Hi Neville, Voltage across the thermoswitch contacts in less than 10VAC. Current is 6-8 mA. Once in failure mode, the mercury column passes the 78C point without causing circuit closure. Instead, a rapidly pulsating open / close with an internal resistance of 50K - 300K is observed. Circuit closure eventually happens at a temperature above 82C. After this overtemp condition, the thermoswitch will perform normally for numerous cycles before going back into failure mode. Once I detected the intermittent thermoswitch failure, I increased voltage and current to see if this would restore reliability. Failures went from minutes and hours to about 12 hours and occasionally days but not good enough to declare success. I haven't increased voltage and current further as I feel that it better to replace the failing component. Thanks, Russ -----Original Message----- From: Neville Michie To: Discussion of precise time and frequency measurement Sent: Tue, 19 Aug 2008 7:46 pm Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard Hi, this is a second attempt at an answer, the first seemed to evaporate. Mercury-in -glass thermometers have formed the basis of a system of thermostats used constant temperature systems of very high performance. A major producer of contact thermometers was Jumo (maybe German). These thermometers had a thin wire that went down the capillary and contacted the mercury at the set temperature. The system could be accurate to 0.005 degree. The control algorithm is alien to modern EEs but used a large thermal mass and a fixed rate of heating to produce a slow temperature ramp. Fast response by the thermometer switching kept overshoot down to millidegrees. A cycle time of 5 or 10 seconds kept a very low amplitude temperature ramp running up and down with mean temperature held quite close. Locating the thermometer close to the heater caused a little over control which reduced overshoot and cycle amplitude. The thermometers had up to 30 mA run through the wire, but more modern units reduced this to 1mA. If the tip is corroded on your thermometer contact, maybe a higher resistance measuring circuit may still operate reliably. Good Luck with the unit, Neville Michie On 20/08/2008, at 9:17 AM, Mark Sims wrote: > > I suspect the only place you would find a replacement themoswitch > is in another unit. I also doubt that any current mechanical > switch will be anywhere near stable and accurate enough. > > I stand by my original comments: Built a solid state functional > replacement in the same form factor as the original unit. It will > be hidden inside the oven assembly where only you will know of the > dastardly deed that you did. If you ever find a replacement > switch, you can install it and bask in its originality. Until > then, bask in its solid state patch enabled oscillatude. > > A non-original part that restores a device to operating condition > is far superior to a dead unit... particularly if the part is not > visible. There are lots of zillion dollar antique cars winning > best-of-show with modern internal engine components (not to mention > bondo and fiberglass under the paint). > ---------------------------------------- > > _________________________________________________________________ > Be the filmmaker you always wanted to beearn how to burn a DVD > with Windows. > http://clk.atdmt.com/MRT/go/108588797/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 Wed Aug 20 02:36:21 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 20 Aug 2008 08:36:21 +0200 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: <48ABBB65.9000301@rubidium.dyndns.org> Jim Palfreyman wrote: > Wow. > > Don't tell me people still use miles? Nautical or otherwise? > > What's wrong with the good old kilometre? If the air industry would go fully metric, which they should eventually, they would have to change many things, like the indicating the level in foots. That alone should hurt with many pilots I guess. They are just pushing the shift further into time in hope they never need to deal with it. There are many manuals that needs to be rewritten, pilot retraining, rules to rewrite besides changing the scale of a few meters in the cockpit. Cheers, Magnus From jim77742 at gmail.com Wed Aug 20 03:01:43 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 20 Aug 2008 17:01:43 +1000 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: <48ABBB65.9000301@rubidium.dyndns.org> References: <011401c9023e$413cc7a0$0c00a8c0@daundell> <48ABBB65.9000301@rubidium.dyndns.org> Message-ID: When I fly in a commercial plane, the display in front of me shows its speed in km/h and height in metres. The pilot announces the same. I would have thought that if any group of people could convert quickly it would be airline pilots. They are intelligent and highly trained people - not likely to get emotional and try and hang on to outdated and silly units. It would make their job easier. Besides I'd be surprised if pilots in Europe (and other places too) didn't use metric exclusively. Jim 2008/8/20 Magnus Danielson > Jim Palfreyman wrote: > > Wow. > > > > Don't tell me people still use miles? Nautical or otherwise? > > > > What's wrong with the good old kilometre? > > If the air industry would go fully metric, which they should eventually, > they would have to change many things, like the indicating the level in > foots. That alone should hurt with many pilots I guess. They are just > pushing the shift further into time in hope they never need to deal with > it. There are many manuals that needs to be rewritten, pilot retraining, > rules to rewrite besides changing the scale of a few meters in the cockpit. > > 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 Wed Aug 20 03:24:57 2008 From: phk at phk.freebsd.dk (Poul-Henning Kamp) Date: Wed, 20 Aug 2008 07:24:57 +0000 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: Your message of "Wed, 20 Aug 2008 17:01:43 +1000." Message-ID: <67812.1219217097@critter.freebsd.dk> In message , "Jim Palfreyman" writes: >When I fly in a commercial plane, the display in front of me shows its speed >in km/h and height in metres. The pilot announces the same. > >I would have thought that if any group of people could convert quickly it >would be airline pilots. Ahh, but it's not just the pilots is it ? It's also all the instruments in the planes, all the lingo with ATC and all the maps. A particular worry would be flightlevels, where it would get really nasty if somebody confuses feet and meter near a major airport. -- 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 fortime at bellsouth.net Wed Aug 20 03:26:40 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 03:26:40 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> Message-ID: <001a01c90296$17ad67c0$a101a8c0@officemail> Russ, In other words, you sound like you are not 100% sure it's the switch. A shame you couldn't graph voltage and current going to the switch as it cycles. Is it possible a cap or something else is intermittently failing in the circuit. Again I'm assuming with that resistance there is something between it and the heater. Though I had one, I don't think I ever looked inside the thing. I have seen some similar units (I think what you have) that use an almost paper thin column of mercury. I would guess that is how they can achieve the fine resolution/precision. Phil ----- Original Message ----- From: To: Cc: Sent: Wednesday, August 20, 2008 2:34 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > Phil, > > The details of the thermoswitch failure are not completely clear. > Intermittently, the mercury column will pass the 78C point without causing > circuit closure. Instead, a pulsating open / close with an internal > resistance of 50K - 300K is observed. Circuit closure eventually happens > at a temperature above 82C. Once an external failure, i.e. lead wiring, > was ruled out, I used a borrowed microscope to view the internal structure > of the thermoswitch. Unfortunately, this did not reveal the failure > source. > > Russ > > -----Original Message----- > From: phil > To: Discussion of precise time and frequency measurement > > Sent: Tue, 19 Aug 2008 9:33 pm > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > > > Neville, > good answer. Perhaps the original poster could supply a photo of his > switch, > perhaps more suggestions could be made. I think we had an old gr-1100 at > one > time, it was a 100kc unit. Needless to say it was scrapped years ago and > I'm > sure it's been melted down and sent back to the usa in tin cans or cars by > now! I'm curious as to how the switch failed. I'm assuming it was a sealed > unit. > Phil > > ----- Original Message ----- > From: "Neville Michie" > To: "Discussion of precise time and frequency measurement" > > Sent: Tuesday, August 19, 2008 7:46 PM > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > > Hi, > this is a second attempt at an answer, the first seemed to evaporate. > Mercury-in -glass thermometers have formed the basis of a system of > thermostats > used constant temperature systems of very high performance. > A major producer of contact thermometers was Jumo (maybe German). > These thermometers had a thin wire that went down the capillary and > contacted the mercury at the set temperature. The system could be > accurate to > 0.005 degree. The control algorithm is alien to modern EEs but used a > large thermal mass and a fixed rate of heating to produce a slow > temperature ramp. > Fast response by the thermometer switching kept overshoot down to > millidegrees. > A cycle time of 5 or 10 seconds kept a very low amplitude temperature > ramp running up and down > with mean temperature held quite close. > Locating the thermometer close to the heater caused a little over > control which reduced overshoot and cycle amplitude. > The thermometers had up to 30 mA run through the wire, but more > modern units reduced this to 1mA. > If the tip is corroded on your thermometer contact, maybe a higher > resistance measuring circuit may > still operate reliably. > Good Luck with the unit, > Neville Michie > > > > > > On 20/08/2008, at 9:17 AM, Mark Sims wrote: > >> >> I suspect the only place you would find a replacement themoswitch >> is in another unit. I also doubt that any current mechanical >> switch will be anywhere near stable and accurate enough. >> >> I stand by my original comments: Built a solid state functional >> replacement in the same form factor as the original unit. It will >> be hidden inside the oven assembly where only you will know of the >> dastardly deed that you did. If you ever find a replacement >> switch, you can install it and bask in its originality. Until >> then, bask in its solid state patch enabled oscillatude. >> >> A non-original part that restores a device to operating condition >> is far superior to a dead unit... particularly if the part is not >> visible. There are lots of zillion dollar antique cars winning >> best-of-show with modern internal engine components (not to mention >> bondo and fiberglass under the paint). >> ---------------------------------------- >> >> _________________________________________________________________ >> Be the filmmaker you always wanted to beearn how to burn a DVD >> with Windows. >> http://clk.atdmt.com/MRT/go/108588797/direct/01/ >> _______________________________________________ >> time-nuts mailing list -- 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 fortime at bellsouth.net Wed Aug 20 03:37:33 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 03:37:33 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday References: <011401c9023e$413cc7a0$0c00a8c0@daundell><48ABBB65.9000301@rubidium.dyndns.org> Message-ID: <002101c90297$9c300600$a101a8c0@officemail> Although English is the worlds standard language for pilots. "intelligent" perhaps, but not all, we put two pilots away for embezzling, one was buying planes to rent and putting them in his name rather than the company name. That's not very intelligent ! ----- Original Message ----- From: "Jim Palfreyman" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, August 20, 2008 3:01 AM Subject: Re: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday > When I fly in a commercial plane, the display in front of me shows its > speed > in km/h and height in metres. The pilot announces the same. > > I would have thought that if any group of people could convert quickly it > would be airline pilots. They are intelligent and highly trained people - > not likely to get emotional and try and hang on to outdated and silly > units. > It would make their job easier. Besides I'd be surprised if pilots in > Europe > (and other places too) didn't use metric exclusively. > > Jim > > > 2008/8/20 Magnus Danielson > >> Jim Palfreyman wrote: >> > Wow. >> > >> > Don't tell me people still use miles? Nautical or otherwise? >> > >> > What's wrong with the good old kilometre? >> >> If the air industry would go fully metric, which they should eventually, >> they would have to change many things, like the indicating the level in >> foots. That alone should hurt with many pilots I guess. They are just >> pushing the shift further into time in hope they never need to deal with >> it. There are many manuals that needs to be rewritten, pilot retraining, >> rules to rewrite besides changing the scale of a few meters in the >> cockpit. >> >> 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. >> > _______________________________________________ > time-nuts mailing list -- 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 Wed Aug 20 03:39:37 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Wed, 20 Aug 2008 03:39:37 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: "Jim Palfreyman" wrote: > >Wow. > >Don't tell me people still use miles? Nautical or otherwise? > >What's wrong with the good old kilometre? > >Jim Tradition. TWA and Pan American opened the long-range routes before WWII. So all the worldwide aviation standards used whatever they were using. In this age of computers, it probably makes little difference except for the confusion it would cause in switching over. That means changing all the documents and training, and the zillions of hidden details based on the old standards. For example, here's happened when the Boeing 767 went all-metric: http://www.damninteresting.com/?p=744 Regards, Mike Monett From fortime at bellsouth.net Wed Aug 20 03:45:00 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 03:45:00 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> Message-ID: <002c01c90298$a69c8590$a101a8c0@officemail> Russ, Also could it be a cold solder joint on the tubes connections, possibly look good but have a high resistance. That could account for an intermittent as you are describing. Sometimes we overlook the simplest of things. Phil ----- Original Message ----- From: "phil" To: ; Sent: Wednesday, August 20, 2008 3:26 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > Russ, > In other words, you sound like you are not 100% sure it's the switch. A > shame you couldn't graph voltage and current going to the switch as it > cycles. Is it possible a cap or something else is intermittently failing > in > the circuit. Again I'm assuming with that resistance there is something > between it and the heater. Though I had one, I don't think I ever looked > inside the thing. > > I have seen some similar units (I think what you have) that use an almost > paper thin column of mercury. I would guess that is how they can achieve > the > fine resolution/precision. > > Phil > > > ----- Original Message ----- > From: > To: > Cc: > Sent: Wednesday, August 20, 2008 2:34 AM > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > >> Phil, >> >> The details of the thermoswitch failure are not completely clear. >> Intermittently, the mercury column will pass the 78C point without >> causing >> circuit closure. Instead, a pulsating open / close with an internal >> resistance of 50K - 300K is observed. Circuit closure eventually happens >> at a temperature above 82C. Once an external failure, i.e. lead wiring, >> was ruled out, I used a borrowed microscope to view the internal >> structure >> of the thermoswitch. Unfortunately, this did not reveal the failure >> source. >> >> Russ >> >> -----Original Message----- >> From: phil >> To: Discussion of precise time and frequency measurement >> >> Sent: Tue, 19 Aug 2008 9:33 pm >> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >> >> >> >> Neville, >> good answer. Perhaps the original poster could supply a photo of his >> switch, >> perhaps more suggestions could be made. I think we had an old gr-1100 at >> one >> time, it was a 100kc unit. Needless to say it was scrapped years ago and >> I'm >> sure it's been melted down and sent back to the usa in tin cans or cars >> by >> now! I'm curious as to how the switch failed. I'm assuming it was a >> sealed >> unit. >> Phil >> >> ----- Original Message ----- >> From: "Neville Michie" >> To: "Discussion of precise time and frequency measurement" >> >> Sent: Tuesday, August 19, 2008 7:46 PM >> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >> >> >> Hi, >> this is a second attempt at an answer, the first seemed to evaporate. >> Mercury-in -glass thermometers have formed the basis of a system of >> thermostats >> used constant temperature systems of very high performance. >> A major producer of contact thermometers was Jumo (maybe German). >> These thermometers had a thin wire that went down the capillary and >> contacted the mercury at the set temperature. The system could be >> accurate to >> 0.005 degree. The control algorithm is alien to modern EEs but used a >> large thermal mass and a fixed rate of heating to produce a slow >> temperature ramp. >> Fast response by the thermometer switching kept overshoot down to >> millidegrees. >> A cycle time of 5 or 10 seconds kept a very low amplitude temperature >> ramp running up and down >> with mean temperature held quite close. >> Locating the thermometer close to the heater caused a little over >> control which reduced overshoot and cycle amplitude. >> The thermometers had up to 30 mA run through the wire, but more >> modern units reduced this to 1mA. >> If the tip is corroded on your thermometer contact, maybe a higher >> resistance measuring circuit may >> still operate reliably. >> Good Luck with the unit, >> Neville Michie >> >> >> >> >> >> On 20/08/2008, at 9:17 AM, Mark Sims wrote: >> >>> >>> I suspect the only place you would find a replacement themoswitch >>> is in another unit. I also doubt that any current mechanical >>> switch will be anywhere near stable and accurate enough. >>> >>> I stand by my original comments: Built a solid state functional >>> replacement in the same form factor as the original unit. It will >>> be hidden inside the oven assembly where only you will know of the >>> dastardly deed that you did. If you ever find a replacement >>> switch, you can install it and bask in its originality. Until >>> then, bask in its solid state patch enabled oscillatude. >>> >>> A non-original part that restores a device to operating condition >>> is far superior to a dead unit... particularly if the part is not >>> visible. There are lots of zillion dollar antique cars winning >>> best-of-show with modern internal engine components (not to mention >>> bondo and fiberglass under the paint). >>> ---------------------------------------- >>> >>> _________________________________________________________________ >>> Be the filmmaker you always wanted to beearn how to burn a DVD >>> with Windows. >>> http://clk.atdmt.com/MRT/go/108588797/direct/01/ >>> _______________________________________________ >>> time-nuts mailing list -- 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 magnus at rubidium.dyndns.org Wed Aug 20 04:16:07 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Wed, 20 Aug 2008 10:16:07 +0200 (CEST) Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: <67812.1219217097@critter.freebsd.dk> References: <67812.1219217097@critter.freebsd.dk> Message-ID: <7ba5bcf56bc018a44afeb7c8ba4a0446.squirrel@rubidium.dyndns.org> > In message , > "Jim > Palfreyman" writes: >>When I fly in a commercial plane, the display in front of me shows its >> speed >>in km/h and height in metres. The pilot announces the same. >> >>I would have thought that if any group of people could convert quickly it >>would be airline pilots. > > Ahh, but it's not just the pilots is it ? > > It's also all the instruments in the planes, all the lingo with ATC and > all the maps. > > A particular worry would be flightlevels, where it would get really > nasty if somebody confuses feet and meter near a major airport. Indeed. Add the stress factor at the time of an incident. This is when the conversion comes in and can be the cause of a major incident rather than just being a small incident. Cheers, Magnus From wa3frp at aol.com Wed Aug 20 04:16:46 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Wed, 20 Aug 2008 04:16:46 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <002c01c90298$a69c8590$a101a8c0@officemail> References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> Message-ID: <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> Phil, I didn't believe that the thermoswitch was the problem, at first, chiefly because of the simplicity of operation. Eventually, after checking wiring, a carbon resistor that is in series with the thermoswitch, and components around the inner oven control circuitry, I removed the thermoswitch to the bench. After hooking up to a ohmmeter and using a 60 watt light bulb as the heat source, I found that I could duplicate the a pulsating open / close as before. I first focused on the bulb leads and eventually completely removed the old leads and rebuilt each one and did all new soldering under magnification. The problem remains the same. I'm ready to move on at this point noting that this component failure has me stumped and that the fault is most likely internal to the thermoswitch (as strange as this seems). Years ago, when I first saw how internal temperature worked using the mercury thermometer switch, I remarked that it was one component that would never fail. HA! That statement came back to haunt me. Best, Russ -----Original Message----- From: phil To: Discussion of precise time and frequency measurement Sent: Wed, 20 Aug 2008 3:45 am Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard Russ, Also could it be a cold solder joint on the tubes connections, possibly look good but have a high resistance. That could account for an intermittent as you are describing. Sometimes we overlook the simplest of things. Phil ----- Original Message ----- From: "phil" To: ; Sent: Wednesday, August 20, 2008 3:26 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > Russ, > In other words, you sound like you are not 100% sure it's the switch. A > shame you couldn't graph voltage and current going to the switch as it > cycles. Is it possible a cap or something else is intermittently failing > in > the circuit. Again I'm assuming with that resistance there is something > between it and the heater. Though I had one, I don't think I ever looked > inside the thing. > > I have seen some similar units (I think what you have) that use an almost > paper thin column of mercury. I would guess that is how they can achieve > the > fine resolution/precision. > > Phil > > > ----- Original Message ----- > From: > To: > Cc: > Sent: Wednesday, August 20, 2008 2:34 AM > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > >> Phil, >> >> The details of the thermoswitch failure are not completely clear. >> Intermittently, the mercury column will pass the 78C point without >> causing >> circuit closure. Instead, a pulsating open / close with an internal >> resistance of 50K - 300K is observed. Circuit closure eventually happens >> at a temperature above 82C. Once an external failure, i.e. lead wiring, >> was ruled out, I used a borrowed microscope to view the internal >> structure >> of the thermoswitch. Unfortunately, this did not reveal the failure >> source. >> >> Russ >> >> -----Original Message----- >> From: phil >> To: Discussion of precise time and frequency measurement >> >> Sent: Tue, 19 Aug 2008 9:33 pm >> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >> >> >> >> Neville, >> good answer. Perhaps the original poster could supply a photo of his >> switch, >> perhaps more suggestions could be made. I think we had an old gr-1100 at >> one >> time, it was a 100kc unit. Needless to say it was scrapped years ago and >> I'm >> sure it's been melted down and sent back to the usa in tin cans or cars >> by >> now! I'm curious as to how the switch failed. I'm assuming it was a >> sealed >> unit. >> Phil >> >> ----- Original Message ----- >> From: "Neville Michie" >> To: "Discussion of precise time and frequency measurement" >> >> Sent: Tuesday, August 19, 2008 7:46 PM >> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >> >> >> Hi, >> this is a second attempt at an answer, the first seemed to evaporate. >> Mercury-in -glass thermometers have formed the basis of a system of >> thermostats >> used constant temperature systems of very high performance. >> A major producer of contact thermometers was Jumo (maybe German). >> These thermometers had a thin wire that went down the capillary and >> contacted the mercury at the set temperature. The system could be >> accurate to >> 0.005 degree. The control algorithm is alien to modern EEs but used a >> large thermal mass and a fixed rate of heating to produce a slow >> temperature ramp. >> Fast response by the thermometer switching kept overshoot down to >> millidegrees. >> A cycle time of 5 or 10 seconds kept a very low amplitude temperature >> ramp running up and down >> with mean temperature held quite close. >> Locating the thermometer close to the heater caused a little over >> control which reduced overshoot and cycle amplitude. >> The thermometers had up to 30 mA run through the wire, but more >> modern units reduced this to 1mA. >> If the tip is corroded on your thermometer contact, maybe a higher >> resistance measuring circuit may >> still operate reliably. >> Good Luck with the unit, >> Neville Michie >> >> >> >> >> >> On 20/08/2008, at 9:17 AM, Mark Sims wrote: >> >>> >>> I suspect the only place you would find a replacement themoswitch >>> is in another unit. I also doubt that any current mechanical >>> switch will be anywhere near stable and accurate enough. >>> >>> I stand by my original comments: Built a solid state functional >>> replacement in the same form factor as the original unit. It will >>> be hidden inside the oven assembly where only you will know of the >>> dastardly deed that you did. If you ever find a replacement >>> switch, you can install it and bask in its originality. Until >>> then, bask in its solid state patch enabled oscillatude. >>> >>> A non-original part that restores a device to operating condition >>> is far superior to a dead unit... particularly if the part is not >>> visible. There are lots of zillion dollar antique cars winning >>> best-of-show with modern internal engine components (not to mention >>> bondo and fiberglass under the paint). >>> ---------------------------------------- >>> >>> _________________________________________________________________ >>> Be the filmmaker you always wanted to beearn how to burn a DVD >>> with Windows. >>> http://clk.atdmt.com/MRT/go/108588797/direct/01/ >>> _______________________________________________ >>> time-nuts mailing list -- 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 XDE-L2G3 at myamail.com Wed Aug 20 05:14:23 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Wed, 20 Aug 2008 05:14:23 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> Message-ID: wa3frp at aol.com wrote: >Phil, > I didn't believe that the thermoswitch was the problem, at first, > chiefly because of the simplicity of operation. Eventually, after > checking wiring, a carbon resistor that is in series with the > thermoswitch, and components around the inner oven control > circuitry, I removed the thermoswitch to the bench. > After hooking up to a ohmmeter and using a 60 watt light bulb as > the heat source, I found that I could duplicate the a pulsating > open / close as before. I first focused on the bulb leads and > eventually completely removed the old leads and rebuilt each one > and did all new soldering under magnification. The problem remains > the same. > I'm ready to move on at this point noting that this component > failure has me stumped and that the fault is most likely internal > to the thermoswitch (as strange as this seems). Years ago, when I > first saw how internal temperature worked using the mercury > thermometer switch, I remarked that it was one component that > would never fail. HA! That statement came back to haunt me. >Best, >Russ I have been following this thread with some interest, as I expect to have similar equipment in the future. What is amazing is how you discovered the problem! Like you, I would not have believed a mercury switch could fail. But a quick search showed the contact can oxidize, and gave several patents aimed at solving the problem: 1. Reduction of oxides in a fluid-based switch - US Patent 7071432, 07/04/2006 Often, oxides may form within the switch and inhibit proper functioning of the switch. For example, the oxides may increase or decrease the surface tension of the liquid metal, which may increase or decrease the energy required for the switch to change state. Oxides can lead to poor switch performance, and even switch failure, because they lessen or prevent a switching fluid from wetting surfaces it is supposed to wet. 2. Preventing corrosion degradation in a fluid-based switch - United States Patent 6781074, 08/24/2004 Liquid metal switches rely on the cleanness of the liquid metal for good performance. If the liquid metal forms oxide films or other types of corrosion product buildup within the switch, the proper functioning or performance of the switch may degrade or be inhibited. For example, the oxide film or other corrosion products may increase the surface tension of the liquid metal, which may increase the energy required for the switch to change state. Films of oxide and other corrosion products may increase the tendency for the liquid metal to wet to the substrate between switch contacts, thereby increasing undesirable short circuits in the switching operation. Build up of oxide and other corrosion products may also degrade the ability of the liquid metal to wet to the switch contacts, and thereby may increase the probability of undesirable open circuits in the switching operation. This is very interesting. Thanks for posting your experience. Best Regards, Mike Monett From fortime at bellsouth.net Wed Aug 20 05:42:26 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 05:42:26 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> Message-ID: <001001c902a9$0e9d7ae0$a101a8c0@officemail> Russ Do you have a photo, would it be possible to build? I have a few flasks of mercury and a few 10's of thousands of mercury wetted relays that some could be cannibalized for electrodes. The trick here is how thin is that column of mercury. My guess the thinner the column, the finer the resolution or the more it will travel with a small temp swing. Better yet, possible to cut that thing open and fix it. I know that's more time than it's worth. Another thought, if the contacts have corroded in the mercury, perhaps from contamination, would it be possible to "burn" the contamination off. Thinking of excessive voltage/current. Perhaps making it arc internally. Trick would be to limit current not to explode the thing, perhaps using a charged capacitor. Just a thought. Oh, do you have the whole rack, all dividers and the clock? I bet the old clock alone is worth a thousand bucks today. Seems like it was driven by 1 KC. My old standard was complete, a 5 or 6 foot rack and came out of an old Hamerland Radio plant. phil ----- Original Message ----- From: To: Cc: Sent: Wednesday, August 20, 2008 4:16 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > Phil, > > I didn't believe that the thermoswitch was the problem, at first, chiefly > because of the simplicity of operation. Eventually, after checking wiring, > a carbon resistor that is in series with the thermoswitch, and components > around the inner oven control circuitry, I removed the thermoswitch to the > bench. > > After hooking up to a ohmmeter and using a 60 watt light bulb as the heat > source, I found that I could duplicate the > a pulsating open / close as before. I first focused on the bulb leads and > eventually completely removed the old leads and rebuilt each one and did > all new soldering under magnification. The problem remains the same. > > I'm ready to move on at this point noting that this component failure has > me stumped and that the fault is most likely internal to the thermoswitch > (as strange as this seems). Years ago, when I first saw how internal > temperature worked using the mercury thermometer switch, I remarked that > it was one component that would never fail. HA! That statement came back > to haunt me. > > Best, > > Russ > > > -----Original Message----- > From: phil > To: Discussion of precise time and frequency measurement > > Sent: Wed, 20 Aug 2008 3:45 am > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > > > Russ, > Also could it be a cold solder joint on the tubes connections, possibly > look > good but have a high resistance. That could account for an intermittent as > you are describing. Sometimes we overlook the simplest of things. > Phil > > > ----- Original Message ----- > From: "phil" > To: ; > Sent: Wednesday, August 20, 2008 3:26 AM > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > >> Russ, >> In other words, you sound like you are not 100% sure it's the switch. > A >> shame you couldn't graph voltage and current going to the switch as it >> cycles. Is it possible a cap or something else is intermittently > failing >> in >> the circuit. Again I'm assuming with that resistance there is > something >> between it and the heater. Though I had one, I don't think I ever > looked >> inside the thing. >> >> I have seen some similar units (I think what you have) that use an > almost >> paper thin column of mercury. I would guess that is how they can > achieve >> the >> fine resolution/precision. >> >> Phil >> >> >> ----- Original Message ----- >> From: >> To: >> Cc: >> Sent: Wednesday, August 20, 2008 2:34 AM >> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >> >> >>> Phil, >>> >>> The details of the thermoswitch failure are not completely clear. >>> Intermittently, the mercury column will pass the 78C point without >>> causing >>> circuit closure. Instead, a pulsating open / close with an internal >>> resistance of 50K - 300K is observed. Circuit closure eventually > happens >>> at a temperature above 82C. Once an external failure, i.e. lead > wiring, >>> was ruled out, I used a borrowed microscope to view the internal >>> structure >>> of the thermoswitch. Unfortunately, this did not reveal the failure >>> source. >>> >>> Russ >>> >>> -----Original Message----- >>> From: phil >>> To: Discussion of precise time and frequency measurement >>> >>> Sent: Tue, 19 Aug 2008 9:33 pm >>> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >>> >>> >>> >>> Neville, >>> good answer. Perhaps the original poster could supply a photo of his >>> switch, >>> perhaps more suggestions could be made. I think we had an old > gr-1100 at >>> one >>> time, it was a 100kc unit. Needless to say it was scrapped years ago > and >>> I'm >>> sure it's been melted down and sent back to the usa in tin cans or > cars >>> by >>> now! I'm curious as to how the switch failed. I'm assuming it was a >>> sealed >>> unit. >>> Phil >>> >>> ----- Original Message ----- >>> From: "Neville Michie" >>> To: "Discussion of precise time and frequency measurement" >>> >>> Sent: Tuesday, August 19, 2008 7:46 PM >>> Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard >>> >>> >>> Hi, >>> this is a second attempt at an answer, the first seemed to evaporate. >>> Mercury-in -glass thermometers have formed the basis of a system of >>> thermostats >>> used constant temperature systems of very high performance. >>> A major producer of contact thermometers was Jumo (maybe German). >>> These thermometers had a thin wire that went down the capillary and >>> contacted the mercury at the set temperature. The system could be >>> accurate to >>> 0.005 degree. The control algorithm is alien to modern EEs but used a >>> large thermal mass and a fixed rate of heating to produce a slow >>> temperature ramp. >>> Fast response by the thermometer switching kept overshoot down to >>> millidegrees. >>> A cycle time of 5 or 10 seconds kept a very low amplitude temperature >>> ramp running up and down >>> with mean temperature held quite close. >>> Locating the thermometer close to the heater caused a little over >>> control which reduced overshoot and cycle amplitude. >>> The thermometers had up to 30 mA run through the wire, but more >>> modern units reduced this to 1mA. >>> If the tip is corroded on your thermometer contact, maybe a higher >>> resistance measuring circuit may >>> still operate reliably. >>> Good Luck with the unit, >>> Neville Michie >>> >>> >>> >>> >>> >>> On 20/08/2008, at 9:17 AM, Mark Sims wrote: >>> >>>> >>>> I suspect the only place you would find a replacement themoswitch >>>> is in another unit. I also doubt that any current mechanical >>>> switch will be anywhere near stable and accurate enough. >>>> >>>> I stand by my original comments: Built a solid state functional >>>> replacement in the same form factor as the original unit. It will >>>> be hidden inside the oven assembly where only you will know of the >>>> dastardly deed that you did. If you ever find a replacement >>>> switch, you can install it and bask in its originality. Until >>>> then, bask in its solid state patch enabled oscillatude. >>>> >>>> A non-original part that restores a device to operating condition >>>> is far superior to a dead unit... particularly if the part is not >>>> visible. There are lots of zillion dollar antique cars winning >>>> best-of-show with modern internal engine components (not to mention >>>> bondo and fiberglass under the paint). >>>> ---------------------------------------- >>>> >>>> _________________________________________________________________ >>>> Be the filmmaker you always wanted to beearn how to burn a DVD >>>> with Windows. >>>> http://clk.atdmt.com/MRT/go/108588797/direct/01/ >>>> _______________________________________________ >>>> time-nuts mailing list -- 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 bruce.griffiths at xtra.co.nz Wed Aug 20 06:19:56 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 20 Aug 2008 22:19:56 +1200 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <001001c902a9$0e9d7ae0$a101a8c0@officemail> References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> <001001c902a9$0e9d7ae0$a101a8c0@officemail> Message-ID: <48ABEFCC.5060604@xtra.co.nz> phil wrote: > Russ > Do you have a photo, would it be possible to build? I have a few flasks of > mercury and a few 10's of thousands of mercury wetted relays that some could > be cannibalized for electrodes. The trick here is how thin is that column of > mercury. My guess the thinner the column, the finer the resolution or the > more it will travel with a small temp swing. Better yet, possible to cut > that thing open and fix it. > I know that's more time than it's worth. > > Another thought, if the contacts have corroded in the mercury, perhaps from > contamination, would it be possible to "burn" the contamination off. > Thinking of excessive voltage/current. Perhaps making it arc internally. > Trick would be to limit current not to explode the thing, perhaps using a > charged capacitor. Just a thought. > > Oh, do you have the whole rack, all dividers and the clock? I bet the old > clock alone is worth a thousand bucks today. Seems like it was driven by 1 > KC. My old standard was complete, a 5 or 6 foot rack and came out of an old > Hamerland Radio plant. > > phil > > > Phil NBS used platinum wires in their mercury toluene thermoregulators. These were constructed from pyrex as it proved more stable than stainless steel. These themoregulators had a sensitivity of about 0.001C and were used to regulate the temperature of oil baths, Bruce From fortime at bellsouth.net Wed Aug 20 06:49:51 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 06:49:51 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com><001001c902a9$0e9d7ae0$a101a8c0@officemail> <48ABEFCC.5060604@xtra.co.nz> Message-ID: <000601c902b2$79a91c50$a101a8c0@officemail> Bruce, what was the diameter or how was the column situated to give those resolutions. ----- Original Message ----- From: "Bruce Griffiths" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, August 20, 2008 6:19 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > phil wrote: >> Russ >> Do you have a photo, would it be possible to build? I have a few flasks >> of >> mercury and a few 10's of thousands of mercury wetted relays that some >> could >> be cannibalized for electrodes. The trick here is how thin is that column >> of >> mercury. My guess the thinner the column, the finer the resolution or the >> more it will travel with a small temp swing. Better yet, possible to cut >> that thing open and fix it. >> I know that's more time than it's worth. >> >> Another thought, if the contacts have corroded in the mercury, perhaps >> from >> contamination, would it be possible to "burn" the contamination off. >> Thinking of excessive voltage/current. Perhaps making it arc internally. >> Trick would be to limit current not to explode the thing, perhaps using a >> charged capacitor. Just a thought. >> >> Oh, do you have the whole rack, all dividers and the clock? I bet the old >> clock alone is worth a thousand bucks today. Seems like it was driven by >> 1 >> KC. My old standard was complete, a 5 or 6 foot rack and came out of an >> old >> Hamerland Radio plant. >> >> phil >> >> >> > Phil > > NBS used platinum wires in their mercury toluene thermoregulators. > These were constructed from pyrex as it proved more stable than > stainless steel. > These themoregulators had a sensitivity of about 0.001C and were used to > regulate the temperature of oil baths, > > 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 vilgotch at bigpond.net.au Wed Aug 20 07:00:52 2008 From: vilgotch at bigpond.net.au (Morris Odell) Date: Wed, 20 Aug 2008 21:00:52 +1000 Subject: [time-nuts] 5061A ion pump P/S problem References: Message-ID: <003001c902b4$0332f5d0$ad00a8c0@Morris1> Corby, Thanks very much for this advice. It turned out the spare unit was quite OK after all. It's installed as I type, and the 5061A is locked beautifully and showing the same freq as the Z3815A GPSDO on a HP 5345 counter. A check of the "flop" parameters shows the Cs tube is nice & healthy and all's right with the world!!! The unit had been running with the mode switch in the "Cs off" position for a couple of years so the tube was well and truly pumped down. The ion current was very close to zero. I have a Shera controller circuit built into the unused battery compartment so most of the time it runs as a GPSDO but I like to exercise the Cesium from time to time too. Thanks again Corby and everyone else who suggested ways to get it going again. Morris PS: my 5345 counter does not have the GPIB option so I can't do things like Allen plots. If anyone happens to have a junker with a GPIB card available I'd love to hear about it. > From: corby d dawson > Subject: Re: [time-nuts] 5061A ion pump P/S problem > To: time-nuts at febo.com > Message-ID: <20080819.090934.-558537.0.cdelect at juno.com> > Content-Type: text/plain; charset=us-ascii > > Morris, > > You implied that you tested the spare module on the bench. > > You must connect the -side of the supply to the case of the module as > well as the pin. (this occurs in the unit by its connection to the > chassis) > > If you don't the supply floats and you will only read about 1/2 the > voltage out. From bruce.griffiths at xtra.co.nz Wed Aug 20 07:05:36 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 20 Aug 2008 23:05:36 +1200 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <000601c902b2$79a91c50$a101a8c0@officemail> References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com><001001c902a9$0e9d7ae0$a101a8c0@officemail> <48ABEFCC.5060604@xtra.co.nz> <000601c902b2$79a91c50$a101a8c0@officemail> Message-ID: <48ABFA80.30908@xtra.co.nz> phil wrote: > Bruce, what was the diameter or how was the column situated to give those > resolutions. > > > > Phil The thermoregulator consisted of a horizontal ring tube filled with toluene connected to a 13" long J -tube filled with mercury and containing a capillary section at the top. The top contact consisted of platinum wire within and parallel to the capillary section, the mercury entered the capillary section and made contact with the tip of the vertical platinum wire therein. The other contact was made via a piece of platinum wire sealed through the side of the glass tube below the capillary section. Thus the top contact platinum wire fine enough to fit within the capillary section of the J tube and to a first approximation the diameter has no effect on the sensitivity which is due to the relatively high thermal expansion of the (highly flammable and somewhat toxic) toluene. Platinum and iron have the advantage that they do not directly form amalgams on contact with mercury and are thus not embrittled by amalgamation. However amalgams of platinum and iron can be formed electrochemically. I have a couple of illustrations of such thermoregulators which I can scan if you wish. Bruce From ka2cdk at cox.net Wed Aug 20 08:36:38 2008 From: ka2cdk at cox.net (Thomas A. Frank) Date: Wed, 20 Aug 2008 08:36:38 -0400 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: <000c01c9028c$2e321180$a101a8c0@officemail> References: <011401c9023e$413cc7a0$0c00a8c0@daundell> <000c01c9028c$2e321180$a101a8c0@officemail> Message-ID: <353E1480-C614-4DB1-A81A-675C13F88586@cox.net> >>> It turns out every one of these units stopped working sometime >>> Sunday and >>> they don't fully understand the cause or the fix as of yet. Good >>> news, I >>> don't have a malfunctioning unit. >> >> Funny, but to me, having the thing stop working qualifies as >> "malfunctioning". >> >> Just a thought. >> >> Tom Frank, KA2CDK >> > > "malfunctioning"? > Can it be said, if you have a task that you are being paid big > bucks an hour > to perform, and have to stop in the middle to go the little boys > room that > you are "malfunctioning"? Nah, that would be more like recharging the batteries. A known and *expected* maintenance function. That can (sometimes :-)) be postponed until after important things are complete. Now if I went home and crawled into bed and stayed there indefinitely, that would be malfunctioning. There have been weeks where that might have been a better solution in all regards than working! But I digress. > A firmware update is a heck of a lot better than a "blown up" unit. True, but it's still a brick until that happens. Expected vs. unexpected. The scary thing is, the vendor could eventually say "sorry, we can't fix it, buy a new one". The ultimate malfunction, and you don't get two weeks notice... Tom Frank P.S. - no offense taken. From Arnold.Tibus at gmx.de Wed Aug 20 08:51:18 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Wed, 20 Aug 2008 14:51:18 +0200 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: Message-ID: On Wed, 20 Aug 2008 16:24:31 +1000, Jim Palfreyman wrote: >Wow. >Don't tell me people still use miles? Nautical or otherwise? >What's wrong with the good old kilometre? >Jim Jim, it is quite easy to give an answer to your question: Even using GPS geographic coordinates are still (and will be in future) in use, because the earth is a globe (even a bit deformed like a potato but is not a flat surface like a disk ;-) ! ) with a circumference of roughly 40000 km divided in 360? or 21600 (arc)min = 21600 nautical miles (NM or nmi). Nautical charts are divided in degrees and minutes by a grid of intersecting lines thus allowing very easy and quick to measure distances positions and passages just applying a nautical divider (attn.: to me adjusted o n l y on the right or left side of the chart, the meridians N or S value!) To avoid nm (nanometers) with nautical miles: The preferred abbreviation of the IEEE is nmi For aviation use, the preferred abbreviation of the ICAO is NM A nmi = 0.9998834 mean meridian arc minutes = mean historical nautical miles (approx.) In 1929 when the International Extraordinary Hydrographic Conference held in Monaco was adopted a definition of one (1) international nautical mile as being equal to 1,852 m exactly. more eg.: http://en.wikipedia.org/wiki/Nautical_mile http://encyclopedia.farlex.com/nautical+mile http://citadelnavy.files.wordpress.com/2008/02/02-terrestrial-coord-sys-charts.ppt I think even in 'modern' times the use of nmi will therefore not disappear! regards Arnold From fortime at bellsouth.net Wed Aug 20 09:00:18 2008 From: fortime at bellsouth.net (phil) Date: Wed, 20 Aug 2008 09:00:18 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com><001001c902a9$0e9d7ae0$a101a8c0@officemail> <48ABEFCC.5060604@xtra.co.nz><000601c902b2$79a91c50$a101a8c0@officemail> <48ABFA80.30908@xtra.co.nz> Message-ID: <000e01c902c4$b2dc2ff0$a101a8c0@officemail> Bruce, nuf said, in that case it's the expansion of toluene, not the mercury. Can easily see how that would work, actually rather ingenious. As always, more than one way to do something. Thanks, Phil ----- Original Message ----- From: "Bruce Griffiths" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, August 20, 2008 7:05 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > phil wrote: >> Bruce, what was the diameter or how was the column situated to give those >> resolutions. >> >> >> >> > Phil > > The thermoregulator consisted of a horizontal ring tube filled with > toluene connected to a 13" long J -tube filled with mercury and > containing a capillary section at the top. > The top contact consisted of platinum wire within and parallel to the > capillary section, the mercury entered the capillary section and made > contact with the tip of the vertical platinum wire therein. > The other contact was made via a piece of platinum wire sealed through > the side of the glass tube below the capillary section. > Thus the top contact platinum wire fine enough to fit within the > capillary section of the J tube and to a first approximation the > diameter has no effect on the sensitivity which is due to the relatively > high thermal expansion of the (highly flammable and somewhat toxic) > toluene. > > Platinum and iron have the advantage that they do not directly form > amalgams on contact with mercury and are thus not embrittled by > amalgamation. > However amalgams of platinum and iron can be formed electrochemically. > > I have a couple of illustrations of such thermoregulators which I can > scan if you wish. > > 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 wa3frp at aol.com Wed Aug 20 09:42:39 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Wed, 20 Aug 2008 09:42:39 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> Message-ID: <8CAD0E1BF1ACECE-F94-A18@FWM-M02.sysops.aol.com> Hi Mike, Yes I feel that you have nailed the root cause of the failure. That explains the failures observed here. Thanks and Best Regards, Russ -----Original Message----- From: Mike Monett To: time-nuts at febo.com Sent: Wed, 20 Aug 2008 5:14 am Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard wa3frp at aol.com wrote: >Phil, > I didn't believe that the thermoswitch was the problem, at first, > chiefly because of the simplicity of operation. Eventually, after > checking wiring, a carbon resistor that is in series with the > thermoswitch, and components around the inner oven control > circuitry, I removed the thermoswitch to the bench. > After hooking up to a ohmmeter and using a 60 watt light bulb as > the heat source, I found that I could duplicate the a pulsating > open / close as before. I first focused on the bulb leads and > eventually completely removed the old leads and rebuilt each one > and did all new soldering under magnification. The problem remains > the same. > I'm ready to move on at this point noting that this component > failure has me stumped and that the fault is most likely internal > to the thermoswitch (as strange as this seems). Years ago, when I > first saw how internal temperature worked using the mercury > thermometer switch, I remarked that it was one component that > would never fail. HA! That statement came back to haunt me. >Best, >Russ I have been following this thread with some interest, as I expect to have similar equipment in the future. What is amazing is how you discovered the problem! Like you, I would not have believed a mercury switch could fail. But a quick search showed the contact can oxidize, and gave several patents aimed at solving the problem: 1. Reduction of oxides in a fluid-based switch - US Patent 7071432, 07/04/2006 Often, oxides may form within the switch and inhibit proper functioning of the switch. For example, the oxides may increase or decrease the surface tension of the liquid metal, which may increase or decrease the energy required for the switch to change state. Oxides can lead to poor switch performance, and even switch failure, because they lessen or prevent a switching fluid from wetting surfaces it is supposed to wet. 2. Preventing corrosion degradation in a fluid-based switch - United States Patent 6781074, 08/24/2004 Liquid metal switches rely on the cleanness of the liquid metal for good performance. If the liquid metal forms oxide films or other types of corrosion product buildup within the switch, the proper functioning or performance of the switch may degrade or be inhibited. For example, the oxide film or other corrosion products may increase the surface tension of the liquid metal, which may increase the energy required for the switch to change state. Films of oxide and other corrosion products may increase the tendency for the liquid metal to wet to the substrate between switch contacts, thereby increasing undesirable short circuits in the switching operation. Build up of oxide and other corrosion products may also degrade the ability of the liquid metal to wet to the switch contacts, and thereby may increase the probability of undesirable open circuits in the switching operation. This is very interesting. Thanks for posting your experience. Best Regards, Mike Monett _______________________________________________ time-nuts mailing list -- 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 Wed Aug 20 09:56:16 2008 From: james.p.lux at jpl.nasa.gov (Jim Lux) Date: Wed, 20 Aug 2008 06:56:16 -0700 Subject: [time-nuts] FW: IIMorrow GPS units non-functional since Sunday In-Reply-To: References: <011401c9023e$413cc7a0$0c00a8c0@daundell> Message-ID: <20080820065616.sz5fppye8kosk84c@webmail.jpl.nasa.gov> Quoting Jim Palfreyman , on Tue 19 Aug 2008 11:24:31 PM PDT: > Wow. > > Don't tell me people still use miles? Nautical or otherwise? > > What's wrong with the good old kilometre? > > Jim Simple...Britannia ruled the seas, while the Cassinis measured the earth. Why the prime meridian is in Greenwich and we use meters for length. And, if you're navigating a boat, the fact that 1 minute of latitude is a nautical mile is fairly convenient. If you know your current position, and that where you want to be, and you can approximate the cosine of your latitude, you can figure out distances to within a few percent in your head, making a plane earth assumption, which is probably reasonable for a day's run in most boats. Do you want to try and navigate the Straits of Magellan or the local harbor this way.. probably not. But, for getting from one port to the next, it's "good enough" Jim Lux From N3IZN at aol.com Wed Aug 20 20:17:43 2008 From: N3IZN at aol.com (N3IZN at aol.com) Date: Wed, 20 Aug 2008 20:17:43 EDT Subject: [time-nuts] AT&T(Lucent) ED2R849-31 G4 Message-ID: Any one ever dig in to one of these? Anything useful in there? It has a 10 Mhz output. Thanks **************It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv00050000000047) From tob at starhouse.org Wed Aug 20 22:47:47 2008 From: tob at starhouse.org (Tom Bales) Date: Wed, 20 Aug 2008 22:47:47 -0400 Subject: [time-nuts] Efratom LPRO Rubidium Message-ID: Charles, I see from a posting of yours on time-nuts that you have the Lucent RFTGm-Rb and RFTGm-XO pair and the monitor program to go along with it. I just recently got one of these setups, and it seems to be working (Rb says "online," XO says "standby," Do you have the Lucent monitoring software that looks at the RS-422 output? I can see there's data there, and it decodes to gobbledygook rather than ASCII characters, so I suppose there's a magic decoder ring that's needed. Sure would be nice to know what's going on inside. Thanks, Tom Bales From VK3FGJM at commtelns.com Wed Aug 20 23:34:38 2008 From: VK3FGJM at commtelns.com (VK3FGJM) Date: Thu, 21 Aug 2008 13:34:38 +1000 Subject: [time-nuts] Efratom LPRO Rubidium In-Reply-To: References: Message-ID: Hi Charles, Would it be possible to share the software with other, or could we look at some screen shots for a start? Like Tom, I have a Lucent Rb and XO set, and I have given up trying to reverse engineer it's bowls. Regards Gerald VK3FGJM -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Tom Bales Sent: Thursday, 21 August 2008 12:48 PM To: time-nuts at febo.com Subject: [time-nuts] Efratom LPRO Rubidium Charles, I see from a posting of yours on time-nuts that you have the Lucent RFTGm-Rb and RFTGm-XO pair and the monitor program to go along with it. I just recently got one of these setups, and it seems to be working (Rb says "online," XO says "standby," Do you have the Lucent monitoring software that looks at the RS-422 output? I can see there's data there, and it decodes to gobbledygook rather than ASCII characters, so I suppose there's a magic decoder ring that's needed. Sure would be nice to know what's going on inside. Thanks, Tom Bales _______________________________________________ time-nuts mailing list -- 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 protected by MailGuard: e-mail anti-virus, anti-spam and content filtering. http://www.mailguard.com.au/mg From magnus at rubidium.dyndns.org Thu Aug 21 13:00:16 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Thu, 21 Aug 2008 19:00:16 +0200 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> Message-ID: <48AD9F20.40005@rubidium.dyndns.org> Mike Monett wrote: > wa3frp at aol.com wrote: > > >Phil, > > > I didn't believe that the thermoswitch was the problem, at first, > > chiefly because of the simplicity of operation. Eventually, after > > checking wiring, a carbon resistor that is in series with the > > thermoswitch, and components around the inner oven control > > circuitry, I removed the thermoswitch to the bench. > > > After hooking up to a ohmmeter and using a 60 watt light bulb as > > the heat source, I found that I could duplicate the a pulsating > > open / close as before. I first focused on the bulb leads and > > eventually completely removed the old leads and rebuilt each one > > and did all new soldering under magnification. The problem remains > > the same. > > > I'm ready to move on at this point noting that this component > > failure has me stumped and that the fault is most likely internal > > to the thermoswitch (as strange as this seems). Years ago, when I > > first saw how internal temperature worked using the mercury > > thermometer switch, I remarked that it was one component that > > would never fail. HA! That statement came back to haunt me. > > >Best, > > >Russ > > I have been following this thread with some interest, as I expect to > have similar equipment in the future. What is amazing is how you > discovered the problem! > > Like you, I would not have believed a mercury switch could fail. But > a quick search showed the contact can oxidize, and gave several > patents aimed at solving the problem: > > 1. Reduction of oxides in a fluid-based switch - US Patent 7071432, > 07/04/2006 > > Often, oxides may form within the switch and inhibit proper > functioning of the switch. For example, the oxides may increase or > decrease the surface tension of the liquid metal, which may increase > or decrease the energy required for the switch to change state. > > Oxides can lead to poor switch performance, and even switch failure, > because they lessen or prevent a switching fluid from wetting > surfaces it is supposed to wet. Hmm... but capacitive sensing should still work well. Cheer, Magnus From max at maxsmusicplace.com Thu Aug 21 13:37:05 2008 From: max at maxsmusicplace.com (Max Robinson) Date: Thu, 21 Aug 2008 12:37:05 -0500 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> <48AD9F20.40005@rubidium.dyndns.org> Message-ID: <011c01c903b4$87cc0060$6401a8c0@BACKROOM> When I was at the university I saw and worked on a thermostatic switch that used a standard mercury thermometer. The little thing that clipped on to the thermometer was the capacitor in an oscillator. The detector for opening and closing the relay was a high Q tuned circuit. I saw them regularly because I had to keep teaching lab instructors how to tune them up before each use. In a controlled environment it might be possible to optimize such a circuit for stable operation and tight control. My intuition tells me that 1 degree is about as fine a control as you could get unless you had a very narrow range thermometer with a small capillary. You might be able to convert the existing thermostat to capacitive sensing. That is apparently what Magnus is suggesting. 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: "Magnus Danielson" To: "Discussion of precise time and frequency measurement" Sent: Thursday, August 21, 2008 12:00 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > Mike Monett wrote: >> wa3frp at aol.com wrote: >> >> >Phil, >> >> > I didn't believe that the thermoswitch was the problem, at first, >> > chiefly because of the simplicity of operation. Eventually, after >> > checking wiring, a carbon resistor that is in series with the >> > thermoswitch, and components around the inner oven control >> > circuitry, I removed the thermoswitch to the bench. >> >> > After hooking up to a ohmmeter and using a 60 watt light bulb as >> > the heat source, I found that I could duplicate the a pulsating >> > open / close as before. I first focused on the bulb leads and >> > eventually completely removed the old leads and rebuilt each one >> > and did all new soldering under magnification. The problem remains >> > the same. >> >> > I'm ready to move on at this point noting that this component >> > failure has me stumped and that the fault is most likely internal >> > to the thermoswitch (as strange as this seems). Years ago, when I >> > first saw how internal temperature worked using the mercury >> > thermometer switch, I remarked that it was one component that >> > would never fail. HA! That statement came back to haunt me. >> >> >Best, >> >> >Russ >> >> I have been following this thread with some interest, as I expect to >> have similar equipment in the future. What is amazing is how you >> discovered the problem! >> >> Like you, I would not have believed a mercury switch could fail. But >> a quick search showed the contact can oxidize, and gave several >> patents aimed at solving the problem: >> >> 1. Reduction of oxides in a fluid-based switch - US Patent 7071432, >> 07/04/2006 >> >> Often, oxides may form within the switch and inhibit proper >> functioning of the switch. For example, the oxides may increase or >> decrease the surface tension of the liquid metal, which may increase >> or decrease the energy required for the switch to change state. >> >> Oxides can lead to poor switch performance, and even switch failure, >> because they lessen or prevent a switching fluid from wetting >> surfaces it is supposed to wet. > > Hmm... but capacitive sensing should still work well. > > Cheer, > 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 XDE-L2G3 at myamail.com Thu Aug 21 15:07:43 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Thu, 21 Aug 2008 15:07:43 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com> <001401c90264$d13d2400$a101a8c0@officemail> <8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com> <001a01c90296$17ad67c0$a101a8c0@officemail> <002c01c90298$a69c8590$a101a8c0@officemail> <8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> <48AD9F20.40005@rubidium.dyndns.org> <011c01c903b4$87cc0060$6401a8c0@BACKROOM> Message-ID: "Max Robinson" wrote: > >When I was at the university I saw and worked on a thermostatic switch that >used a standard mercury thermometer. The little thing that clipped on to >the thermometer was the capacitor in an oscillator. The detector for >opening and closing the relay was a high Q tuned circuit. I saw them >regularly because I had to keep teaching lab instructors how to tune them up >before each use. In a controlled environment it might be possible to >optimize such a circuit for stable operation and tight control. My >intuition tells me that 1 degree is about as fine a control as you could get >unless you had a very narrow range thermometer with a small capillary. You >might be able to convert the existing thermostat to capacitive sensing. >That is apparently what Magnus is suggesting. > >Regards. > >Max. K 4 O D S. Optical might work better. Maybe use the lens and laser from an old CDROM. It might be fun getting it to focus on the mercury column through a round glass tube. Or maybe the glass wouldn't even pass the infrared. I got a bad burn once picking up an empty wine glass that was sitting beside a fireplace. But I understand new systems use a blue laser, which might work even better. I wonder what kind of temperature control it would give, and what the long-term drift might be. Sounds like a fun project. Regards, Mike Monett From scmcgrath at gmail.com Thu Aug 21 20:56:49 2008 From: scmcgrath at gmail.com (Scott McGrath) Date: Thu, 21 Aug 2008 20:56:49 -0400 Subject: [time-nuts] Introduction and a couple of requests Message-ID: Hi, Name is Scott McGrath and I am a fellow time nut who in addition to playing with precise timing also plays with clocks!. My current collection of standards includes the following HP 105B HP 117A HP 5061A HP 5065A ( dead physics package unfortunately ) Austron 2100F (sold to me as a T but no internal standard so I am assuming a F) TrueTime DC-XL My requests Manual for the 5065A prefix 1840A I also need some replacement modules for a Tektronix 492A I have many spare modules for this except of course for the ones I need Manuals to Share which I will scan pre-production manual for the 5065A but it is much earlier than my current 5065A and a manual for the 117A which From k7hbg at dslextreme.com Thu Aug 21 20:57:51 2008 From: k7hbg at dslextreme.com (k7hbg at dslextreme.com) Date: Thu, 21 Aug 2008 17:57:51 -0700 (PDT) Subject: [time-nuts] New T-Bolt arrived Message-ID: <353a9a38115ac10ba16005a.20080821175751.x7uot@webmail.dslextreme.com> Hi Everybody; My new t-bolt just arrived from TAPR. I powered it up, connected the comm cable to the PC and it seems to be working like a CHAMP! I have two questions for the group. 1) Is there a satellite (SV) map program available to go along with "TBoltMon"? 2) Who do I thank at TAPR for this splendid little jewel and the great deal? Best regards, Bob K7hbg From max at maxsmusicplace.com Thu Aug 21 23:38:51 2008 From: max at maxsmusicplace.com (Max Robinson) Date: Thu, 21 Aug 2008 22:38:51 -0500 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <315CBE72-FE0E-4320-97E9-64FF91F5A385@gmail.com><001401c90264$d13d2400$a101a8c0@officemail><8CAD0A5E7C2FE0B-794-2239@WEBMAIL-MB15.sysops.aol.com><001a01c90296$17ad67c0$a101a8c0@officemail><002c01c90298$a69c8590$a101a8c0@officemail><8CAD0B438CE983D-C6C-26@mblk-d18.sysops.aol.com> <48AD9F20.40005@rubidium.dyndns.org><011c01c903b4$87cc0060$6401a8c0@BACKROOM> Message-ID: <01f701c90408$9877fe60$6401a8c0@BACKROOM> Hmmm. That sounds like something to be stored away for the day when my thermostat goes bad. Sounds like it would work. 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: "Mike Monett" To: Sent: Thursday, August 21, 2008 2:07 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > "Max Robinson" wrote: >> >>When I was at the university I saw and worked on a thermostatic switch >>that >>used a standard mercury thermometer. The little thing that clipped on to >>the thermometer was the capacitor in an oscillator. The detector for >>opening and closing the relay was a high Q tuned circuit. I saw them >>regularly because I had to keep teaching lab instructors how to tune them >>up >>before each use. In a controlled environment it might be possible to >>optimize such a circuit for stable operation and tight control. My >>intuition tells me that 1 degree is about as fine a control as you could >>get >>unless you had a very narrow range thermometer with a small capillary. >>You >>might be able to convert the existing thermostat to capacitive sensing. >>That is apparently what Magnus is suggesting. >> >>Regards. >> >>Max. K 4 O D S. > > Optical might work better. Maybe use the lens and laser from an old CDROM. > It might be fun getting it to focus on the mercury column through a round > glass tube. Or maybe the glass wouldn't even pass the infrared. I got a > bad > burn once picking up an empty wine glass that was sitting beside a > fireplace. But I understand new systems use a blue laser, which might work > even better. > > I wonder what kind of temperature control it would give, and what the > long-term drift might be. Sounds like a fun project. > > Regards, > > Mike Monett > > > _______________________________________________ > time-nuts mailing list -- 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 kyrrin at bluefeathertech.com Fri Aug 22 01:10:58 2008 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Thu, 21 Aug 2008 22:10:58 -0700 Subject: [time-nuts] Odetics 325 & 425: File recovery Message-ID: <200808212210580401.052FAC56@192.168.42.129> Fellow clockers, I'm still picking up the pieces from a major FTP archive crash that lost me a considerable amount of data. Among the files lost was the .PDF manuals for the Odetics 325 and 425. The firmware files I can recover, as I still have the EPROMs in my original unit, but the manuals are not ones that I have backup copies for. If someone can either send those to me, or tell me where they can be downloaded, it would be much appreciated. Thanks. -=-=-=-=-=-=-=-=-=-=-=- 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 bruce.griffiths at xtra.co.nz Fri Aug 22 01:28:27 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Fri, 22 Aug 2008 15:28:27 +1000 (EST) Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard Message-ID: <805296.17410.qm@web96101.mail.aue.yahoo.com> Max A capacitance bridge using a transformer would be a lot more stable than merely using the capacitance to vary the frequency of an LC oscillator. The advantage of a capacitive sensing technique over a light beam is that it has much simpler and potentially more stable mechanical system than when a the mercury colum interrupts a light beam. Unless of course on has the Mercury column move a moire grating or similar setup such as making the top of the mercury column a reflector in an interferometer system. Bruce From kyrrin at bluefeathertech.com Fri Aug 22 01:34:23 2008 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Thu, 21 Aug 2008 22:34:23 -0700 Subject: [time-nuts] Further FTP recovery Message-ID: <200808212234230100.05451B95@192.168.42.129> Along the lines of my earlier request... If anyone did any downloading from my site in the past year or so, I would greatly appreciate copies of what you downloaded so I can rebuild. I will happily reimburse any postage or media (blank CD-R's, etc.) costs. Thanks much. -=-=-=-=-=-=-=-=-=-=-=- 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 hmurray at megapathdsl.net Fri Aug 22 01:45:55 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Thu, 21 Aug 2008 22:45:55 -0700 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: Message from "Bruce Lane" of "Thu, 21 Aug 2008 22:10:58 PDT." <200808212210580401.052FAC56@192.168.42.129> Message-ID: <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> > I'm still picking up the pieces from a major FTP archive crash that > lost me a considerable amount of data. Disks are cheap. Many years ago, one of the guys I worked with pointed out to me/us that it was cheaper to buy more disks than it was to pay us at our normal sallary to figure out which bits should be saved. You can do a lot of handwaving in that area, but that's the general idea. My straw man for low cost backup is a USB disk. I'm thinking of a real rotating disk rather than the typical flash "disk". The key idea is that after you pull the cable, your system can't trash the bits. That is neither software nor fat fingers will delete anything. It isn't perfect, but it's close and simple. Any interesting bits should be backed up multiple ways. If any time-nuts have bits that aren't (well) backed up, please contact me off line so we can work out some way to add another backup copy to the system. -- These are my opinions, not necessarily my employer's. I hate spam. From kyrrin at bluefeathertech.com Fri Aug 22 02:01:27 2008 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Thu, 21 Aug 2008 23:01:27 -0700 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> References: <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> Message-ID: <200808212301270990.055DE6EE@192.168.42.129> Good eve, *********** REPLY SEPARATOR *********** On 21-Aug-08 at 22:45 Hal Murray wrote: >> I'm still picking up the pieces from a major FTP archive crash that >> lost me a considerable amount of data. > >Disks are cheap. I know. I'm in the process of building a second RAID array which will mirror the first. I already have a newly-redesigned DLT (tape) backup scheme in place. >Any interesting bits should be backed up multiple ways. If any time-nuts >have bits that aren't (well) backed up, please contact me off line so we >can work out some way to add another backup copy to the system. I absolutely agree, and I'm in the process of implementing such. I would strongly encourage others to do the same. Now, with that said... Do you happen to have the two manuals? Or other files that you might have downloaded from me? If there's too much to send as E-mail attachments, I will happily reimburse media and postage costs. Thanks. -=-=-=-=-=-=-=-=-=-=-=- 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 chris.kuethe at gmail.com Fri Aug 22 02:17:20 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Thu, 21 Aug 2008 23:17:20 -0700 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <200808212301270990.055DE6EE@192.168.42.129> References: <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> <200808212301270990.055DE6EE@192.168.42.129> Message-ID: <91981b3e0808212317t1664bbdao43a89ec8c7e29526@mail.gmail.com> On Thu, Aug 21, 2008 at 11:01 PM, Bruce Lane wrote: > Good eve, > > *********** REPLY SEPARATOR *********** > > On 21-Aug-08 at 22:45 Hal Murray wrote: > >>> I'm still picking up the pieces from a major FTP archive crash that >>> lost me a considerable amount of data. >> >>Disks are cheap. > > I know. I'm in the process of building a second RAID array which will mirror the first. I already have a newly-redesigned DLT (tape) backup scheme in place. Sorry, no extra copies of manuals. While on the subject you may want to look at a project called LOCKSS: Lots Of Copies Keep Stuff Safe... it may not map 100% into the problem space but it may suggest a strategy for distributed replicated storage of critical documents. -- GDB has a 'break' feature; why doesn't it have 'fix' too? From didier at cox.net Fri Aug 22 04:30:50 2008 From: didier at cox.net (Didier Juges) Date: Fri, 22 Aug 2008 03:30:50 -0500 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> References: Message from "Bruce Lane" of "Thu, 21 Aug 2008 22:10:58 PDT." <200808212210580401.052FAC56@192.168.42.129> <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> Message-ID: <003001c90431$639dbbc0$0a01a8c0@didierhp> The problem nowadays is not the storage, it's the backup software. I have most of my important data in 4 places: two web sites, main 250 GB hard drive and external 500GB Western Digital USB Hard Drive (highly recommended). What I call "important data" is about 30 GB worth of stuff that is typically copied in all 4 places. The problem is keeping everything in sync. Syncing between two local resources (main hard drive and USB hard drive) is not too hard, considering the transfer speed that can be achieved, but mirroring the web resources is a pain, partly because of speed and partly because of OS differences in file name rules (Windows/Linux). I have not found the software I wanted (only looked at free/cheap stuff) so I am considering writing my own (Visual Basic). If anyone has suggestions for free/cheap commercial or FOS software to sync via ftp (Windows <-> Linux), I'll be glad to hear. Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray > Sent: Friday, August 22, 2008 12:46 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Odetics 325 & 425: File recovery > > > > I'm still picking up the pieces from a major FTP > archive crash that > > lost me a considerable amount of data. > > Disks are cheap. > > Many years ago, one of the guys I worked with pointed out to > me/us that it was cheaper to buy more disks than it was to > pay us at our normal sallary to figure out which bits should > be saved. You can do a lot of handwaving in that area, but > that's the general idea. > > My straw man for low cost backup is a USB disk. I'm thinking > of a real rotating disk rather than the typical flash "disk". > The key idea is that after you pull the cable, your system > can't trash the bits. That is neither software nor fat > fingers will delete anything. It isn't perfect, but it's > close and simple. > > > Any interesting bits should be backed up multiple ways. If > any time-nuts > have bits that aren't (well) backed up, please contact me off > line so we can work out some way to add another backup copy > to the system. > > > > -- > 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 chris.cheney at tesco.net Fri Aug 22 06:03:21 2008 From: chris.cheney at tesco.net (Chris Cheney) Date: Fri, 22 Aug 2008 11:03:21 +0100 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <003001c90431$639dbbc0$0a01a8c0@didierhp> References: , <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net>, <003001c90431$639dbbc0$0a01a8c0@didierhp> Message-ID: <48AE9CF9.15914.A0DF3A@chris.cheney.tesco.net> > everything in sync. Syncing between two local resources (main hard drive > and USB hard drive) is not too hard, considering the transfer speed that > can be achieved, but mirroring the web resources is a pain, partly because > of speed and partly because of OS differences in file name rules > (Windows/Linux). I have not found the software I wanted (only looked at > free/cheap stuff) so I am considering writing my own (Visual Basic). Didier, The other OS difference is the way that they deal with file timestamps w.r.t. DST. What Windows does is a real PITA - see http://www.peterdonis.net/computers/computersarticle3.html for the details - right down to the footnote. Have fun with it - it caused me some severe headaches! Chris G3RSE From jdb at lartmaker.nl Fri Aug 22 06:18:10 2008 From: jdb at lartmaker.nl (J.D. Bakker) Date: Fri, 22 Aug 2008 12:18:10 +0200 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <003001c90431$639dbbc0$0a01a8c0@didierhp> References: Message from "Bruce Lane" of "Thu, 21 Aug 2008 22:10:58 PDT." <200808212210580401.052FAC56@192.168.42.129> <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> <003001c90431$639dbbc0$0a01a8c0@didierhp> Message-ID: >If anyone has suggestions for free/cheap commercial or FOS software to sync >via ftp (Windows <-> Linux), I'll be glad to hear. I am very happy with rsync. I have it set up so that it automatically syncs several repositories (including one on a different continent). It has been a while since I used rsync with Windows, but as far as I can tell it does work as expected (and even has facilities to deal with the timestamp issues mentioned in another post). HTH, JDB. -- LART. 250 MIPS under one Watt. Free hardware design files. http://www.lartmaker.nl/ From wje at quackers.net Fri Aug 22 07:19:44 2008 From: wje at quackers.net (wje) Date: Fri, 22 Aug 2008 07:19:44 -0400 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <003001c90431$639dbbc0$0a01a8c0@didierhp> References: Message from "Bruce Lane" of "Thu, 21 Aug 2008 22:10:58 PDT." <200808212210580401.052FAC56@192.168.42.129> <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> <003001c90431$639dbbc0$0a01a8c0@didierhp> Message-ID: <48AEA0D0.4070607@quackers.net> Rsync works quite well on both Linux and Windows. I use it to back up my lab computer (XP), my work computer (Vista, unfortunately), several family computers (XP), and my primary Linux system. There's an excellent bit of freeware, Delta Copy, that provides rsync for the Windows side, either on command or via scheduled tasks. Another big benefit of rsync is that it does intelligent backups, only backing up what's changed. BTW, a raid array is a really good idea, too. I back up everything from the primary Linux box to an Infrant/Netgrar ReadyNAS 1Tb raid 5 box, also via rsync. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Didier Juges wrote: The problem nowadays is not the storage, it's the backup software. I have most of my important data in 4 places: two web sites, main 250 GB hard drive and external 500GB Western Digital USB Hard Drive (highly recommended). What I call "important data" is about 30 GB worth of stuff that is typically copied in all 4 places. The problem is keeping everything in sync. Syncing between two local resources (main hard drive and USB hard drive) is not too hard, considering the transfer speed that can be achieved, but mirroring the web resources is a pain, partly because of speed and partly because of OS differences in file name rules (Windows/Linux). I have not found the software I wanted (only looked at free/cheap stuff) so I am considering writing my own (Visual Basic). If anyone has suggestions for free/cheap commercial or FOS software to sync via ftp (Windows <-> Linux), I'll be glad to hear. Didier KO4BB -----Original Message----- From: [1]time-nuts-bounces at febo.com [[2]mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray Sent: Friday, August 22, 2008 12:46 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Odetics 325 & 425: File recovery I'm still picking up the pieces from a major FTP archive crash that lost me a considerable amount of data. Disks are cheap. Many years ago, one of the guys I worked with pointed out to me/us that it was cheaper to buy more disks than it was to pay us at our normal sallary to figure out which bits should be saved. You can do a lot of handwaving in that area, but that's the general idea. My straw man for low cost backup is a USB disk. I'm thinking of a real rotating disk rather than the typical flash "disk". The key idea is that after you pull the cable, your system can't trash the bits. That is neither software nor fat fingers will delete anything. It isn't perfect, but it's close and simple. Any interesting bits should be backed up multiple ways. If any time-nuts have bits that aren't (well) backed up, please contact me off line so we can work out some way to add another backup copy to the system. -- These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ time-nuts mailing list -- [3]time-nuts at febo.com To unsubscribe, go to [4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [5]time-nuts at febo.com To unsubscribe, go to [6]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts-bounces at febo.com 2. mailto:time-nuts-bounces at febo.com 3. mailto:time-nuts at febo.com 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 5. mailto:time-nuts at febo.com 6. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From XDE-L2G3 at myamail.com Fri Aug 22 09:20:11 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Fri, 22 Aug 2008 09:20:11 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <805296.17410.qm@web96101.mail.aue.yahoo.com> Message-ID: Bruce Griffiths wrote: > Max > A capacitance bridge using a transformer would be a lot more > stable than merely using the capacitance to vary the frequency of > an LC oscillator. > The advantage of a capacitive sensing technique over a light beam > is that it has much simpler and potentially more stable mechanical > system than when a the mercury colum interrupts a light beam. > Unless of course on has the Mercury column move a moire grating or > similar setup such as making the top of the mercury column a > reflector in an interferometer system. > Bruce Very clever! According to this web page, interferometry could give a resolution of 0.15 nm, or close to the radius of a silver atom: http://www.aerotech.com/products/engref/intexe.html This video shows the basic principle in case you want to make your own: http://www.metacafe.com/watch/1381543/laser_interferometer_homemade_for_20/ You can see from the movement of the fringes how sensitive interferometry can be. This should give unprecedented temperature control, so maybe someone has already done it. A google search gives lots of hits, but it is difficult to distinguish between controlling the termperature of something, and the need for accurate control of temperature to get stable fringes! Great idea! Regards, Mike Monett From kyrrin at bluefeathertech.com Fri Aug 22 09:56:58 2008 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Fri, 22 Aug 2008 06:56:58 -0700 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <003001c90431$639dbbc0$0a01a8c0@didierhp> References: Message from "Bruce Lane" <200808212210580401.052FAC56@192.168.42.129> <20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net> <003001c90431$639dbbc0$0a01a8c0@didierhp> Message-ID: <200808220656580705.071141BD@192.168.42.129> Hi, Didier, I absolutely agree, and Dave Slack has given me some good suggestions along those lines. Among them was an open-source product called 'rsync.' This is the link for it. http://samba.anu.edu.au/rsync/ Happy tweaking. *********** REPLY SEPARATOR *********** On 22-Aug-08 at 03:30 Didier Juges wrote: >The problem nowadays is not the storage, it's the backup software. > >I have most of my important data in 4 places: two web sites, main 250 GB >hard drive and external 500GB Western Digital USB Hard Drive (highly >recommended). What I call "important data" is about 30 GB worth of stuff >that is typically copied in all 4 places. The problem is keeping everything >in sync. Syncing between two local resources (main hard drive and USB hard >drive) is not too hard, considering the transfer speed that can be >achieved, >but mirroring the web resources is a pain, partly because of speed and >partly because of OS differences in file name rules (Windows/Linux). I have >not found the software I wanted (only looked at free/cheap stuff) so I am >considering writing my own (Visual Basic). > >If anyone has suggestions for free/cheap commercial or FOS software to sync >via ftp (Windows <-> Linux), I'll be glad to hear. > >Didier KO4BB > > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray >> Sent: Friday, August 22, 2008 12:46 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Odetics 325 & 425: File recovery >> >> >> > I'm still picking up the pieces from a major FTP >> archive crash that >> > lost me a considerable amount of data. >> >> Disks are cheap. >> >> Many years ago, one of the guys I worked with pointed out to >> me/us that it was cheaper to buy more disks than it was to >> pay us at our normal sallary to figure out which bits should >> be saved. You can do a lot of handwaving in that area, but >> that's the general idea. >> >> My straw man for low cost backup is a USB disk. I'm thinking >> of a real rotating disk rather than the typical flash "disk". >> The key idea is that after you pull the cable, your system >> can't trash the bits. That is neither software nor fat >> fingers will delete anything. It isn't perfect, but it's >> close and simple. >> >> >> Any interesting bits should be backed up multiple ways. If >> any time-nuts >> have bits that aren't (well) backed up, please contact me off >> line so we can work out some way to add another backup copy >> to the system. >> >> >> >> -- >> 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. -=-=-=-=-=-=-=-=-=-=-=- 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 kyrrin at bluefeathertech.com Fri Aug 22 10:02:04 2008 From: kyrrin at bluefeathertech.com (Bruce Lane) Date: Fri, 22 Aug 2008 07:02:04 -0700 Subject: [time-nuts] Odetics manuals recovered, thanks! Message-ID: <200808220702040797.0715ED7A@192.168.42.129> With thanks (again) to Peter Vince, I've recovered the Odetics manuals I was after, and some bonus ones as well. Today, among other things, I will be working on recovering the firmware files I had. FWIW -- When I get the site resurrected, there will be no weird ports or other bizarre settings. I'm just going to leave things on Port 21, standard, and deal with the inevitable script-kiddies and other abusers through judicious application of IPfilter. Keep the peace(es). -=-=-=-=-=-=-=-=-=-=-=- 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 fortime at bellsouth.net Fri Aug 22 10:27:07 2008 From: fortime at bellsouth.net (phil) Date: Fri, 22 Aug 2008 10:27:07 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <805296.17410.qm@web96101.mail.aue.yahoo.com> Message-ID: <001601c90463$286aefa0$a101a8c0@officemail> Gentlemen, Original poster is trying to "RESTORE" this entire old General Radio Standard ( a rack of equipment) to it's "original" glory. He simply needs a part, a unique thermoswitch or a way to fix it, not retrofit an atomic engine! This is a museum class instrument, 100kc. May I suggest start a new thread on the better/best merits/design of temperature control. Makes it rather difficult to follow a thread as the subject has changed. Respectfully Phil ----- Original Message ----- From: "Mike Monett" To: Sent: Friday, August 22, 2008 9:20 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > Bruce Griffiths wrote: > > > Max > > > A capacitance bridge using a transformer would be a lot more > > stable than merely using the capacitance to vary the frequency of > > an LC oscillator. > > > The advantage of a capacitive sensing technique over a light beam > > is that it has much simpler and potentially more stable mechanical > > system than when a the mercury colum interrupts a light beam. > > > Unless of course on has the Mercury column move a moire grating or > > similar setup such as making the top of the mercury column a > > reflector in an interferometer system. > > > Bruce > > Very clever! According to this web page, interferometry could give a > resolution of 0.15 nm, or close to the radius of a silver atom: > > http://www.aerotech.com/products/engref/intexe.html > > This video shows the basic principle in case you want to make your > own: > > > http://www.metacafe.com/watch/1381543/laser_interferometer_homemade_for_20/ > > You can see from the movement of the fringes how sensitive > interferometry can be. This should give unprecedented temperature > control, so maybe someone has already done it. A google search gives > lots of hits, but it is difficult to distinguish between controlling > the termperature of something, and the need for accurate control of > temperature to get stable fringes! > > Great idea! > > Regards, > > Mike Monett > > _______________________________________________ > time-nuts mailing list -- 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 w9ddd at tapr.org Fri Aug 22 12:06:58 2008 From: w9ddd at tapr.org (John Koster) Date: Fri, 22 Aug 2008 11:06:58 -0500 (CDT) Subject: [time-nuts] ATTN Wen-chiang Huang In-Reply-To: Message-ID: Wilfred, please contact the TAPR office or me off list ASAP. Direct emails don't seem to be reaching you. (check spam folders?) If you don't have the tapr office email address, you can use the following form: https://www.tapr.org/inforequest.php?call=taproffice -- 73, John, W9DDD From rk at timing-consultants.com Fri Aug 22 12:52:12 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Fri, 22 Aug 2008 17:52:12 +0100 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <200808220656580705.071141BD@192.168.42.129> References: Message from "Bruce Lane" <200808212210580401.052FAC56@192.168.42.129><20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net><003001c90431$639dbbc0$0a01a8c0@didierhp> <200808220656580705.071141BD@192.168.42.129> Message-ID: <124EBB73F35F4F339EC3080B3754513E@Robin> For Windows users, I have been using FileSync for a number of years, and very happy with it. Great for incremental backups to external USB drives. Got my fingers burnt a few years ago after a hard disk failure, and now regularly backup my hard drives to three external drives (real belt and braces solution!!). All drives indexed and searchable using Copernic Desktop Search (much friendlier than the Google and Windows versions) FileSync available from http://www.fileware.com/ Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Bruce Lane Sent: 22 August 2008 14:57 To: time-nuts at febo.com Subject: Re: [time-nuts] Odetics 325 & 425: File recovery Hi, Didier, I absolutely agree, and Dave Slack has given me some good suggestions along those lines. Among them was an open-source product called 'rsync.' This is the link for it. http://samba.anu.edu.au/rsync/ Happy tweaking. *********** REPLY SEPARATOR *********** On 22-Aug-08 at 03:30 Didier Juges wrote: >The problem nowadays is not the storage, it's the backup software. > >I have most of my important data in 4 places: two web sites, main 250 >GB hard drive and external 500GB Western Digital USB Hard Drive (highly >recommended). What I call "important data" is about 30 GB worth of >stuff that is typically copied in all 4 places. The problem is keeping >everything in sync. Syncing between two local resources (main hard >drive and USB hard >drive) is not too hard, considering the transfer speed that can be >achieved, but mirroring the web resources is a pain, partly because of >speed and partly because of OS differences in file name rules >(Windows/Linux). I have not found the software I wanted (only looked at >free/cheap stuff) so I am considering writing my own (Visual Basic). > >If anyone has suggestions for free/cheap commercial or FOS software to >sync via ftp (Windows <-> Linux), I'll be glad to hear. > >Didier KO4BB > > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray >> Sent: Friday, August 22, 2008 12:46 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Odetics 325 & 425: File recovery >> >> >> > I'm still picking up the pieces from a major FTP >> archive crash that >> > lost me a considerable amount of data. >> >> Disks are cheap. >> >> Many years ago, one of the guys I worked with pointed out to me/us >> that it was cheaper to buy more disks than it was to pay us at our >> normal sallary to figure out which bits should be saved. You can do >> a lot of handwaving in that area, but that's the general idea. >> >> My straw man for low cost backup is a USB disk. I'm thinking of a >> real rotating disk rather than the typical flash "disk". >> The key idea is that after you pull the cable, your system can't >> trash the bits. That is neither software nor fat fingers will delete >> anything. It isn't perfect, but it's close and simple. >> >> >> Any interesting bits should be backed up multiple ways. If >> any time-nuts >> have bits that aren't (well) backed up, please contact me off line so >> we can work out some way to add another backup copy to the system. >> >> >> >> -- >> 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. -=-=-=-=-=-=-=-=-=-=-=- 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..." _______________________________________________ time-nuts mailing list -- 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 rk at timing-consultants.com Fri Aug 22 13:28:15 2008 From: rk at timing-consultants.com (Rob Kimberley) Date: Fri, 22 Aug 2008 18:28:15 +0100 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <124EBB73F35F4F339EC3080B3754513E@Robin> References: Message from "Bruce Lane"<200808212210580401.052FAC56@192.168.42.129><20080822054556.CE1D8BCD0@ip-64-139-1-69.sjc.megapath.net><003001c90431$639dbbc0$0a01a8c0@didierhp><200808220656580705.071141BD@192.168.42.129> <124EBB73F35F4F339EC3080B3754513E@Robin> Message-ID: <4E50C9C453264A238E200F4FAED9D5DC@Robin> Forgot to mention they have another program on their web site for FTP back up called FTPSync. Rob -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Rob Kimberley Sent: 22 August 2008 17:52 To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Odetics 325 & 425: File recovery For Windows users, I have been using FileSync for a number of years, and very happy with it. Great for incremental backups to external USB drives. Got my fingers burnt a few years ago after a hard disk failure, and now regularly backup my hard drives to three external drives (real belt and braces solution!!). All drives indexed and searchable using Copernic Desktop Search (much friendlier than the Google and Windows versions) FileSync available from http://www.fileware.com/ Rob Kimberley -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Bruce Lane Sent: 22 August 2008 14:57 To: time-nuts at febo.com Subject: Re: [time-nuts] Odetics 325 & 425: File recovery Hi, Didier, I absolutely agree, and Dave Slack has given me some good suggestions along those lines. Among them was an open-source product called 'rsync.' This is the link for it. http://samba.anu.edu.au/rsync/ Happy tweaking. *********** REPLY SEPARATOR *********** On 22-Aug-08 at 03:30 Didier Juges wrote: >The problem nowadays is not the storage, it's the backup software. > >I have most of my important data in 4 places: two web sites, main 250 >GB hard drive and external 500GB Western Digital USB Hard Drive (highly >recommended). What I call "important data" is about 30 GB worth of >stuff that is typically copied in all 4 places. The problem is keeping >everything in sync. Syncing between two local resources (main hard >drive and USB hard >drive) is not too hard, considering the transfer speed that can be >achieved, but mirroring the web resources is a pain, partly because of >speed and partly because of OS differences in file name rules >(Windows/Linux). I have not found the software I wanted (only looked at >free/cheap stuff) so I am considering writing my own (Visual Basic). > >If anyone has suggestions for free/cheap commercial or FOS software to >sync via ftp (Windows <-> Linux), I'll be glad to hear. > >Didier KO4BB > > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray >> Sent: Friday, August 22, 2008 12:46 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Odetics 325 & 425: File recovery >> >> >> > I'm still picking up the pieces from a major FTP >> archive crash that >> > lost me a considerable amount of data. >> >> Disks are cheap. >> >> Many years ago, one of the guys I worked with pointed out to me/us >> that it was cheaper to buy more disks than it was to pay us at our >> normal sallary to figure out which bits should be saved. You can do >> a lot of handwaving in that area, but that's the general idea. >> >> My straw man for low cost backup is a USB disk. I'm thinking of a >> real rotating disk rather than the typical flash "disk". >> The key idea is that after you pull the cable, your system can't >> trash the bits. That is neither software nor fat fingers will delete >> anything. It isn't perfect, but it's close and simple. >> >> >> Any interesting bits should be backed up multiple ways. If >> any time-nuts >> have bits that aren't (well) backed up, please contact me off line so >> we can work out some way to add another backup copy to the system. >> >> >> >> -- >> 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. -=-=-=-=-=-=-=-=-=-=-=- 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..." _______________________________________________ time-nuts mailing list -- 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 scmcgrath at gmail.com Fri Aug 22 13:36:11 2008 From: scmcgrath at gmail.com (Scott McGrath) Date: Fri, 22 Aug 2008 13:36:11 -0400 Subject: [time-nuts] Time Nuts at Boxboro Message-ID: Anyone going to to the ARRL Regional convention in Boxborough MA this weekend? From didier at cox.net Fri Aug 22 13:48:00 2008 From: didier at cox.net (Didier Juges) Date: Fri, 22 Aug 2008 13:48:00 -0400 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <200808220656580705.071141BD@192.168.42.129> Message-ID: <20080822134800.QIH1J.319631.imail@eastrmwml30> Several people pointed me to rsync. I remember now why I do not use it. rsync requires a client tool and a server tool, so you have to have one part running on each machine. My ISPs do not provide telnet access, just ftp, so I have to use a tool that runs on the local Windows machine (I could use a local Linux box if that's the only way) and that accesses the other machine via ftp. So, unless I am reading this wrong, rsync is out of the question for me. I can run all sorts of programs on the remote Linux box, as long as I can run them through the cgi interface, so that precludes any kind of console based interactive program. At the moment, I have a Perl script that creates an index of all the files on the remote machine (I use that for the Search function on my Manuals pages), so I am considering writing a tool that compares the local and remote directory structures using that index so that I know which files have to be moved in what direction. I just don't need another software project at the moment... Didier ---- Bruce Lane wrote: > Hi, Didier, > > I absolutely agree, and Dave Slack has given me some good suggestions along those lines. > > Among them was an open-source product called 'rsync.' This is the link for it. > > http://samba.anu.edu.au/rsync/ > > Happy tweaking. > > *********** REPLY SEPARATOR *********** > > On 22-Aug-08 at 03:30 Didier Juges wrote: > > >The problem nowadays is not the storage, it's the backup software. > > > >I have most of my important data in 4 places: two web sites, main 250 GB > >hard drive and external 500GB Western Digital USB Hard Drive (highly > >recommended). What I call "important data" is about 30 GB worth of stuff > >that is typically copied in all 4 places. The problem is keeping everything > >in sync. Syncing between two local resources (main hard drive and USB hard > >drive) is not too hard, considering the transfer speed that can be > >achieved, > >but mirroring the web resources is a pain, partly because of speed and > >partly because of OS differences in file name rules (Windows/Linux). I have > >not found the software I wanted (only looked at free/cheap stuff) so I am > >considering writing my own (Visual Basic). > > > >If anyone has suggestions for free/cheap commercial or FOS software to sync > >via ftp (Windows <-> Linux), I'll be glad to hear. > > > >Didier KO4BB > > > > > >> -----Original Message----- > >> From: time-nuts-bounces at febo.com > >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray > >> Sent: Friday, August 22, 2008 12:46 AM > >> To: Discussion of precise time and frequency measurement > >> Subject: Re: [time-nuts] Odetics 325 & 425: File recovery > >> > >> > >> > I'm still picking up the pieces from a major FTP > >> archive crash that > >> > lost me a considerable amount of data. > >> > >> Disks are cheap. > >> > >> Many years ago, one of the guys I worked with pointed out to > >> me/us that it was cheaper to buy more disks than it was to > >> pay us at our normal sallary to figure out which bits should > >> be saved. You can do a lot of handwaving in that area, but > >> that's the general idea. > >> > >> My straw man for low cost backup is a USB disk. I'm thinking > >> of a real rotating disk rather than the typical flash "disk". > >> The key idea is that after you pull the cable, your system > >> can't trash the bits. That is neither software nor fat > >> fingers will delete anything. It isn't perfect, but it's > >> close and simple. > >> > >> > >> Any interesting bits should be backed up multiple ways. If > >> any time-nuts > >> have bits that aren't (well) backed up, please contact me off > >> line so we can work out some way to add another backup copy > >> to the system. > >> > >> > >> > >> -- > >> 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. > > > -=-=-=-=-=-=-=-=-=-=-=- > 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..." > > > _______________________________________________ > time-nuts mailing list -- 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 Aug 22 13:55:08 2008 From: jra at febo.com (John Ackermann N8UR) Date: Fri, 22 Aug 2008 13:55:08 -0400 Subject: [time-nuts] Odetics 325 & 425: File recovery In-Reply-To: <20080822134800.QIH1J.319631.imail@eastrmwml30> References: <20080822134800.QIH1J.319631.imail@eastrmwml30> Message-ID: <48AEFD7C.5090901@febo.com> You can pipe rsync over SSH; a lot of folks who (quite rightly) don't permit telnet leave the SSH ports open, and it's a lot more secure for your data, anyway. I don't recall the exact magic to make rsync plus SSH work under Windows, but I think you could use PuTTY or Teraterm to provide the port forwarding. John ---- Didier Juges wrote: > Several people pointed me to rsync. I remember now why I do not use it. rsync requires a client tool and a server tool, so you have to have one part running on each machine. My ISPs do not provide telnet access, just ftp, so I have to use a tool that runs on the local Windows machine (I could use a local Linux box if that's the only way) and that accesses the other machine via ftp. > > So, unless I am reading this wrong, rsync is out of the question for me. > > I can run all sorts of programs on the remote Linux box, as long as I can run them through the cgi interface, so that precludes any kind of console based interactive program. At the moment, I have a Perl script that creates an index of all the files on the remote machine (I use that for the Search function on my Manuals pages), so I am considering writing a tool that compares the local and remote directory structures using that index so that I know which files have to be moved in what direction. I just don't need another software project at the moment... > > Didier > > ---- Bruce Lane wrote: >> Hi, Didier, >> >> I absolutely agree, and Dave Slack has given me some good suggestions along those lines. >> >> Among them was an open-source product called 'rsync.' This is the link for it. >> >> http://samba.anu.edu.au/rsync/ >> >> Happy tweaking. >> >> *********** REPLY SEPARATOR *********** >> >> On 22-Aug-08 at 03:30 Didier Juges wrote: >> >>> The problem nowadays is not the storage, it's the backup software. >>> >>> I have most of my important data in 4 places: two web sites, main 250 GB >>> hard drive and external 500GB Western Digital USB Hard Drive (highly >>> recommended). What I call "important data" is about 30 GB worth of stuff >>> that is typically copied in all 4 places. The problem is keeping everything >>> in sync. Syncing between two local resources (main hard drive and USB hard >>> drive) is not too hard, considering the transfer speed that can be >>> achieved, >>> but mirroring the web resources is a pain, partly because of speed and >>> partly because of OS differences in file name rules (Windows/Linux). I have >>> not found the software I wanted (only looked at free/cheap stuff) so I am >>> considering writing my own (Visual Basic). >>> >>> If anyone has suggestions for free/cheap commercial or FOS software to sync >>> via ftp (Windows <-> Linux), I'll be glad to hear. >>> >>> Didier KO4BB >>> >>> >>>> -----Original Message----- >>>> From: time-nuts-bounces at febo.com >>>> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray >>>> Sent: Friday, August 22, 2008 12:46 AM >>>> To: Discussion of precise time and frequency measurement >>>> Subject: Re: [time-nuts] Odetics 325 & 425: File recovery >>>> >>>> >>>>> I'm still picking up the pieces from a major FTP >>>> archive crash that >>>>> lost me a considerable amount of data. >>>> Disks are cheap. >>>> >>>> Many years ago, one of the guys I worked with pointed out to >>>> me/us that it was cheaper to buy more disks than it was to >>>> pay us at our normal sallary to figure out which bits should >>>> be saved. You can do a lot of handwaving in that area, but >>>> that's the general idea. >>>> >>>> My straw man for low cost backup is a USB disk. I'm thinking >>>> of a real rotating disk rather than the typical flash "disk". >>>> The key idea is that after you pull the cable, your system >>>> can't trash the bits. That is neither software nor fat >>>> fingers will delete anything. It isn't perfect, but it's >>>> close and simple. >>>> >>>> >>>> Any interesting bits should be backed up multiple ways. If >>>> any time-nuts >>>> have bits that aren't (well) backed up, please contact me off >>>> line so we can work out some way to add another backup copy >>>> to the system. >>>> >>>> >>>> >>>> -- >>>> 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. >> >> -=-=-=-=-=-=-=-=-=-=-=- >> 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..." >> >> >> _______________________________________________ >> time-nuts mailing list -- 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 ch at murgatroid.com Fri Aug 22 14:27:29 2008 From: ch at murgatroid.com (christopher hoover) Date: Fri, 22 Aug 2008 11:27:29 -0700 Subject: [time-nuts] rsync (was Odetics 325 & 425: File recovery) In-Reply-To: References: Message-ID: <008b01c90484$bc3601e0$34a205a0$@com> John Ackermann N8UR wrote: > You can pipe rsync over SSH; > I don't recall the exact magic to make rsync plus > SSH work under Windows, but I think you could use PuTTY or Teraterm to > provide the port forwarding. No port forwading is necessary nor recommended. rsync does ssh natively when you specify user at host: I.e.: rsync dir1 user at host:/dir2 This how rsync is used 98% of the time. (If you actually want to speak to an honest-to-goodness rsync server that's already running, you have to use the rsync:// url syntax.) -ch From jra at febo.com Fri Aug 22 14:38:55 2008 From: jra at febo.com (John Ackermann N8UR) Date: Fri, 22 Aug 2008 14:38:55 -0400 Subject: [time-nuts] rsync (was Odetics 325 & 425: File recovery) In-Reply-To: <008b01c90484$bc3601e0$34a205a0$@com> References: <008b01c90484$bc3601e0$34a205a0$@com> Message-ID: <48AF07BF.50205@febo.com> I was thinking about the Windows side; do the client/server there have built-in SSH support? I thought you had to play tricks under that OS. John christopher hoover wrote: > John Ackermann N8UR wrote: >> You can pipe rsync over SSH; >> I don't recall the exact magic to make rsync plus >> SSH work under Windows, but I think you could use PuTTY or Teraterm to >> provide the port forwarding. > > No port forwading is necessary nor recommended. > > rsync does ssh natively when you specify user at host: I.e.: > > rsync dir1 user at host:/dir2 > > This how rsync is used 98% of the time. > > (If you actually want to speak to an honest-to-goodness rsync server that's > already running, you have to use the rsync:// url syntax.) > > -ch > > > > > _______________________________________________ > time-nuts mailing list -- 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 chris.kuethe at gmail.com Fri Aug 22 14:54:01 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Fri, 22 Aug 2008 11:54:01 -0700 Subject: [time-nuts] rsync (was Odetics 325 & 425: File recovery) In-Reply-To: <48AF07BF.50205@febo.com> References: <008b01c90484$bc3601e0$34a205a0$@com> <48AF07BF.50205@febo.com> Message-ID: <91981b3e0808221154p6c7b4acdrab7197858c8aaa76@mail.gmail.com> cwrsync. works well, comes with a pre-packaged opensshd On Fri, Aug 22, 2008 at 11:38 AM, John Ackermann N8UR wrote: > I was thinking about the Windows side; do the client/server there have > built-in SSH support? I thought you had to play tricks under that OS. > > John > > christopher hoover wrote: >> John Ackermann N8UR wrote: >>> You can pipe rsync over SSH; >>> I don't recall the exact magic to make rsync plus >>> SSH work under Windows, but I think you could use PuTTY or Teraterm to >>> provide the port forwarding. >> >> No port forwading is necessary nor recommended. >> >> rsync does ssh natively when you specify user at host: I.e.: >> >> rsync dir1 user at host:/dir2 >> >> This how rsync is used 98% of the time. >> >> (If you actually want to speak to an honest-to-goodness rsync server that's >> already running, you have to use the rsync:// url syntax.) >> >> -ch >> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- 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. > -- GDB has a 'break' feature; why doesn't it have 'fix' too? From wb6bnq at cox.net Fri Aug 22 15:32:06 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Fri, 22 Aug 2008 12:32:06 -0700 Subject: [time-nuts] Laser Temperature System References: <805296.17410.qm@web96101.mail.aue.yahoo.com> Message-ID: <48AF1436.A8FC527A@cox.net> WAS Re: [time-nuts] Restoring GR 1120-AB Frequency Standard Mike, I fail to see how you would apply the laser interferometer system to the measurement of temperature. At least as a viable means of temperature control to any reasonable degree. At the Navy's Primary Standards Lab, here in San Diego, there is a very complete laser interferometer measurement system. It is housed in its own room that is "completely" controlled for environmental conditions, i.e., temperature, humidity, air filtration, etc. The actual laser platform is a huge, highly machined micro-flat granite table of considerable weight mounted to a fine grain concrete pillar that goes down to the bedrock, some 30 feet below, and is completely separate from the rest of the building's foundation. When the operator enters this laser room, it takes a little over 30 minutes for his body heat to be stabilized into the matrix of the rooms environment before any real measurements can be made. Even though this granite table is, like in the neighborhood of, around 2000 lb., laying a standard U.S. Navy glass coffee cup (empty) on the very, very corner of the granite will deform the light beam quite visually. My reason for the above description is to point out the scale of the installation, the sensitivities and the problematic issues one would have in trying to control temperature sans everything else changing. I suppose it can be reduced in size, but then doing so also reduces the sensitivity of the system. Did I mention that the granite table is 3 feet square ? That allows for folded beams to increase the length for the needed sensitivity. Now equate all of the above to a small oven in an instrument. Not likely possible. Bill....WB6BNQ Mike Monett wrote: Bruce Griffiths wrote: > Max > A capacitance bridge using a transformer would be a lot more > stable than merely using the capacitance to vary the frequency of > an LC oscillator. > The advantage of a capacitive sensing technique over a light beam > is that it has much simpler and potentially more stable mechanical > system than when a the mercury colum interrupts a light beam. > Unless of course on has the Mercury column move a moire grating or > similar setup such as making the top of the mercury column a > reflector in an interferometer system. > Bruce Very clever! According to this web page, interferometry could give a resolution of 0.15 nm, or close to the radius of a silver atom: [1]http://www.aerotech.com/products/engref/intexe.html This video shows the basic principle in case you want to make your own: [2]http://www.metacafe.com/watch/1381543/laser_interferometer_homema de_for_20/ You can see from the movement of the fringes how sensitive interferometry can be. This should give unprecedented temperature control, so maybe someone has already done it. A google search gives lots of hits, but it is difficult to distinguish between controlling the termperature of something, and the need for accurate control of temperature to get stable fringes! Great idea! Regards, Mike Monett _______________________________________________ time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to [3]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. http://www.aerotech.com/products/engref/intexe.html 2. http://www.metacafe.com/watch/1381543/laser_interferometer_homemade_for_20/ 3. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From XDE-L2G3 at myamail.com Fri Aug 22 17:12:57 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Fri, 22 Aug 2008 17:12:57 -0400 Subject: [time-nuts] Laser Temperature System References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <48AF1436.A8FC527A@cox.net> Message-ID: WB6BNQ wrote: > WAS Re: time-nuts Restoring GR 1120-AB Frequency Standard > Mike, > I fail to see how you would apply the laser interferometer system > to the measurement of temperature. At least as a viable means of > temperature control to any reasonable degree. > At the Navy's Primary Standards Lab, here in San Diego, there is a > very complete laser interferometer measurement system. It is > housed in its own room that is "completely" controlled for > environmental conditions, i.e., temperature, humidity, air > filtration, etc. The actual laser platform is a huge, highly > machined micro-flat granite table of considerable weight mounted > to a fine grain concrete pillar that goes down to the bedrock, > some 30 feet below, and is completely separate from the rest of > the building's foundation. > When the operator enters this laser room, it takes a little over > 30 minutes for his body heat to be stabilized into the matrix of > the rooms environment before any real measurements can be made. > Even though this granite table is, like in the neighborhood of, > around 2000 lb., laying a standard US Navy glass coffee cup > (empty) on the very, very corner of the granite will deform the > light beam quite visually. > My reason for the above description is to point out the scale of > the installation, the sensitivities and the problematic issues one > would have in trying to control temperature sans everything else > changing. I suppose it can be reduced in size, but then doing so > also reduces the sensitivity of the system. Did I mention that the > granite table is 3 feet square ? That allows for folded beams to > increase the length for the needed sensitivity. > Now equate all of the above to a small oven in an instrument. Not > likely possible. > Bill. WB6BNQ Hi Bill, Thanks for the info. I am quite familiar with using laser interferometers on granite slabs. I used them for precise positioning to write servo tracks for hard disk drives, but mine were a bit bigger than 3ft. I am also familiar with the original Michleson-Morley interferometer. It was in the basement of a building at MIT for many years. It used folded beams to increase the patch length to measure motion through the ether. No motion was found. A laser interferometer doesn't need folded beams to increase the sensitivity. It simply compares two light beams in a static assembly. One beam is the reference, and the other is reflected from the object. Since the wavelength of red light is about 0.63 micron, the assembly could be quite small, and could be on the order of a few micrometers. The original HP 5525A Laser Interferometer was introduced in 1971, and gave a resolution of 1 um. The interferometer head that contained the laser and electronics was 5" high, 7" wide, and 20.7" long: http://www.n4mw.com/hp5526/hp71.pdf I recall setting it up to measure the length of a very thick I-beam about 3 ft long. You could put a quarter in the middle and see the bar shrink in length due to the droop from the extra weight. So everything is made of rubber at micrometer dimensions, and you really want to get the package as small as possible to minimize errors due to stress and strain. The Aerotech's LZR series laser interferometers are about the same size as the original HP 5525A, but they can give a resolution of 0.3 nm. You can see a picture of how it is used for precise positioning here: http://www.aerotech.com/products/pdf/fg2000.pdf Clearly, some care is needed to maintain constant temperature and minimize vibration. But a room such as you describe is not needed. Regarding miniaturization, the early Cesium Clocks were large enough to fill a room. The HP HP5071A was quite a bit smaller, but still fairly large: http://tycho.usno.navy.mil/cesium.html Now, NIST has shrunk a cesium clock to the size of a grain of rice: http://tf.nist.gov/ofm/smallclock/index.htm Since both technologies contain a somewhat similar modulated light source, optics, and electronics, there is no reason to believe an interferometer could not be made as small. And it would make an outstanding temperature sensor! Regards, Mike Monett From magnus at rubidium.dyndns.org Fri Aug 22 17:25:31 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Fri, 22 Aug 2008 23:25:31 +0200 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <001601c90463$286aefa0$a101a8c0@officemail> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> Message-ID: <48AF2ECB.7040506@rubidium.dyndns.org> phil wrote: > Gentlemen, > Original poster is trying to "RESTORE" this entire old General Radio > Standard ( a rack of equipment) to it's "original" glory. > He simply needs a part, a unique thermoswitch or a way to fix it, not > retrofit an atomic engine! This is a museum class instrument, 100kc. > > May I suggest start a new thread on the better/best merits/design of > temperature control. > Makes it rather difficult to follow a thread as the subject has changed. My proposal to use capacitive sensing rather than conductive sensing would handle the electrode oxide issue. It is meant as a means to go around the sensing issue with parts at hand and only some new electronic design of very simple form, not the means to supercalibrate something. I guess this only shows that time-nuts are time-nuts... Cheers, Magnus From bruce.griffiths at xtra.co.nz Fri Aug 22 18:15:14 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 10:15:14 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: <48AF2ECB.7040506@rubidium.dyndns.org> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> Message-ID: <48AF3A72.5090502@xtra.co.nz> Magnus Danielson wrote: > My proposal to use capacitive sensing rather than conductive sensing > would handle the electrode oxide issue. It is meant as a means to go > around the sensing issue with parts at hand and only some new electronic > design of very simple form, not the means to supercalibrate something. > > I guess this only shows that time-nuts are time-nuts... > > Cheers, > Magnus > > Hej Magnus A capacitive sensing AC bridge can be very sensitive, one only has to look at the work of RV Jones at the university of Glasgow in the 50's, 60's and 70's. He and his collaborators used capacitive sensors to detect (among other things) the extrusion of a micrometer shaft as it was clamped to realise just how sensitive it can be. They found it possible to detect length changes of less than 1E-11m with a suitably designed sensor. Even more sensitive capacitance bridge displacement sensors have since been constructed. Off course the critical bridge components have to be maintained at a reasonably constant temperature. Since the most critical component the balancing capacitor in the other bridge arm can be very small it can easily be located in the same controlled temperature environment as the sensor itself. One of the major contributors to instability will be creep in the glass capillary and bulb dimensions. Even with a relatively crude guard ringed coaxial sensor electrode surrounding a capillary tube is capable of submicron sensitivity without undue effort. If one uses a mercury in glass thermometer with say 0.1C resolution with the 0.1C graduation say 0.5mm apart then 1micron change in mercury column length is equivalent to a temperature change of 200uK. The performance will be determined largely by mechanical instabilities not the bridge sensitivity. Bruce From XDE-L2G3 at myamail.com Fri Aug 22 18:43:23 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Fri, 22 Aug 2008 18:43:23 -0400 Subject: [time-nuts] Capacitive temperature sensing References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> Message-ID: Bruce Griffiths wrote: >Hej Magnus > A capacitive sensing AC bridge can be very sensitive, one only has > to look at the work of RV Jones at the university of Glasgow in > the 50's, 60's and 70's. He and his collaborators used capacitive > sensors to detect (among other things) the extrusion of a > micrometer shaft as it was clamped to realise just how sensitive > it can be. > They found it possible to detect length changes of less than > 1E-11m with a suitably designed sensor. > Even more sensitive capacitance bridge displacement sensors have > since been constructed. [...] >Bruce Bruce, very interesting. I didn't know capacitive sensors went down that low. That could be useful in other areas. I searched google but found nothing. Do you have any urls? Regards, Mike Monett From bruce.griffiths at xtra.co.nz Fri Aug 22 19:30:53 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 11:30:53 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> Message-ID: <48AF4C2D.6000301@xtra.co.nz> Mike Monett wrote: > Bruce, very interesting. I didn't know capacitive sensors went down > that low. That could be useful in other areas. > > I searched google but found nothing. Do you have any urls? > > Regards, > > Mike Monett > > Mike The RV Jones papers were published in either the Review of Scientific instruments or the Journal of Sceintific Instruments - I forget which. I'll look for my paper copies when I get back from shopping later today. Sydenham also wrote at least one paper on various capacitive displacement sensors. Physik Instrumente use capacitive displacement sensors with nanometer sensitivity in their piezostages and piezoactuators. Bruce From bruce.griffiths at xtra.co.nz Fri Aug 22 19:35:17 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 11:35:17 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> Message-ID: <48AF4D35.205@xtra.co.nz> Mike You could also look at Queensgate Instruments. Integral capacitive sensors have been used in a feedback loop to maintain the spacing and parallelism of a pair of Fabry-Perot interferometer plates. Bruce From resolver99 at hotmail.com Fri Aug 22 19:54:25 2008 From: resolver99 at hotmail.com (ron hunt) Date: Fri, 22 Aug 2008 18:54:25 -0500 Subject: [time-nuts] tbolt Message-ID: Well Just Got My Tbolt A Few Days Ago.Finally Got My Antenna Outside And System Came Up In A Few Minutes.Working Great,I Couldn,t Ask For More.Thanks To TAPR And All Involved In This Great Deal.I Have Compared Against My HP 5065A And Can See No Drift Yet.Such A Nice Signal From Such A Small Package! Ron Hunt,Time Nut. _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From didier at cox.net Fri Aug 22 20:16:55 2008 From: didier at cox.net (Didier Juges) Date: Fri, 22 Aug 2008 19:16:55 -0500 Subject: [time-nuts] file synchronization via ftp In-Reply-To: <48AEFD7C.5090901@febo.com> References: <20080822134800.QIH1J.319631.imail@eastrmwml30> <48AEFD7C.5090901@febo.com> Message-ID: <007701c904b5$8dc3c960$0a01a8c0@didierhp> I would have to upgrade to a Business package (instead of the Home package) to have SSH, which would double the cost. I am evaluating FTPSync. It looks like it might do the job, thanks for the suggestion Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of John Ackermann N8UR > Sent: Friday, August 22, 2008 12:55 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Odetics 325 & 425: File recovery > > You can pipe rsync over SSH; a lot of folks who (quite > rightly) don't permit telnet leave the SSH ports open, and > it's a lot more secure for your data, anyway. I don't recall > the exact magic to make rsync plus SSH work under Windows, > but I think you could use PuTTY or Teraterm to provide the > port forwarding. > > John > ---- > > Didier Juges wrote: > > Several people pointed me to rsync. I remember now why I do > not use it. rsync requires a client tool and a server tool, > so you have to have one part running on each machine. My ISPs > do not provide telnet access, just ftp, so I have to use a > tool that runs on the local Windows machine (I could use a > local Linux box if that's the only way) and that accesses the > other machine via ftp. > > > > So, unless I am reading this wrong, rsync is out of the > question for me. > > > > I can run all sorts of programs on the remote Linux box, as > long as I can run them through the cgi interface, so that > precludes any kind of console based interactive program. At > the moment, I have a Perl script that creates an index of all > the files on the remote machine (I use that for the Search > function on my Manuals pages), so I am considering writing a > tool that compares the local and remote directory structures > using that index so that I know which files have to be moved > in what direction. I just don't need another software project > at the moment... > > > > Didier > > > > ---- Bruce Lane wrote: > >> Hi, Didier, > >> > >> I absolutely agree, and Dave Slack has given me some > good suggestions along those lines. > >> > >> Among them was an open-source product called 'rsync.' > This is the link for it. > >> > >> http://samba.anu.edu.au/rsync/ > >> > >> Happy tweaking. > >> > >> *********** REPLY SEPARATOR *********** > >> > >> On 22-Aug-08 at 03:30 Didier Juges wrote: > >> > >>> The problem nowadays is not the storage, it's the backup software. > >>> > >>> I have most of my important data in 4 places: two web sites, main > >>> 250 GB hard drive and external 500GB Western Digital USB > Hard Drive > >>> (highly recommended). What I call "important data" is about 30 GB > >>> worth of stuff that is typically copied in all 4 places. > The problem > >>> is keeping everything in sync. Syncing between two local > resources > >>> (main hard drive and USB hard > >>> drive) is not too hard, considering the transfer speed > that can be > >>> achieved, but mirroring the web resources is a pain, > partly because > >>> of speed and partly because of OS differences in file name rules > >>> (Windows/Linux). I have not found the software I wanted > (only looked > >>> at free/cheap stuff) so I am considering writing my own (Visual > >>> Basic). > >>> > >>> If anyone has suggestions for free/cheap commercial or > FOS software > >>> to sync via ftp (Windows <-> Linux), I'll be glad to hear. > >>> > >>> Didier KO4BB > >>> > >>> > >>>> -----Original Message----- > >>>> From: time-nuts-bounces at febo.com > >>>> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray > >>>> Sent: Friday, August 22, 2008 12:46 AM > >>>> To: Discussion of precise time and frequency measurement > >>>> Subject: Re: [time-nuts] Odetics 325 & 425: File recovery > >>>> > >>>> > >>>>> I'm still picking up the pieces from a major FTP > >>>> archive crash that > >>>>> lost me a considerable amount of data. > >>>> Disks are cheap. > >>>> > >>>> Many years ago, one of the guys I worked with pointed > out to me/us > >>>> that it was cheaper to buy more disks than it was to pay > us at our > >>>> normal sallary to figure out which bits should be saved. > You can > >>>> do a lot of handwaving in that area, but that's the general idea. > >>>> > >>>> My straw man for low cost backup is a USB disk. I'm > thinking of a > >>>> real rotating disk rather than the typical flash "disk". > >>>> The key idea is that after you pull the cable, your > system can't > >>>> trash the bits. That is neither software nor fat fingers will > >>>> delete anything. It isn't perfect, but it's close and simple. > >>>> > >>>> > >>>> Any interesting bits should be backed up multiple ways. If > >>>> any time-nuts > >>>> have bits that aren't (well) backed up, please contact > me off line > >>>> so we can work out some way to add another backup copy to the > >>>> system. > >>>> > >>>> > >>>> > >>>> -- > >>>> 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. > >> > >> -=-=-=-=-=-=-=-=-=-=-=- > >> 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..." > >> > >> > >> _______________________________________________ > >> time-nuts mailing list -- 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 chris.kuethe at gmail.com Fri Aug 22 20:24:59 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Fri, 22 Aug 2008 17:24:59 -0700 Subject: [time-nuts] file synchronization via ftp In-Reply-To: <007701c904b5$8dc3c960$0a01a8c0@didierhp> References: <20080822134800.QIH1J.319631.imail@eastrmwml30> <48AEFD7C.5090901@febo.com> <007701c904b5$8dc3c960$0a01a8c0@didierhp> Message-ID: <91981b3e0808221724i5a485d79if95e3d748ac1c683@mail.gmail.com> On Fri, Aug 22, 2008 at 5:16 PM, Didier Juges wrote: > I would have to upgrade to a Business package (instead of the Home package) > to have SSH, which would double the cost. > > I am evaluating FTPSync. It looks like it might do the job, thanks for the > suggestion Depending on how comfortable you are with scripting, you could just parse the output from "ls -lR" on the ftp server and compare it with a local "ls -lR". If the remote doesn't support "ls -lR", you can automate that yourself. Some ftp clients (like ncftp) are vaguely smart about not transferring duplicate files... -- GDB has a 'break' feature; why doesn't it have 'fix' too? From didier at cox.net Fri Aug 22 20:37:34 2008 From: didier at cox.net (Didier Juges) Date: Fri, 22 Aug 2008 19:37:34 -0500 Subject: [time-nuts] file synchronization via ftp In-Reply-To: <91981b3e0808221724i5a485d79if95e3d748ac1c683@mail.gmail.com> References: <20080822134800.QIH1J.319631.imail@eastrmwml30><48AEFD7C.5090901@febo.com> <007701c904b5$8dc3c960$0a01a8c0@didierhp> <91981b3e0808221724i5a485d79if95e3d748ac1c683@mail.gmail.com> Message-ID: <007a01c904b8$708b9820$0a01a8c0@didierhp> > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Chris Kuethe > Sent: Friday, August 22, 2008 7:25 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] file synchronization via ftp > > On Fri, Aug 22, 2008 at 5:16 PM, Didier Juges wrote: > > I would have to upgrade to a Business package (instead of the Home > > package) to have SSH, which would double the cost. > > > > I am evaluating FTPSync. It looks like it might do the job, > thanks for > > the suggestion > > Depending on how comfortable you are with scripting, you > could just parse the output from "ls -lR" on the ftp server > and compare it with a local "ls -lR". If the remote doesn't > support "ls -lR", you can automate that yourself. Some ftp > clients (like ncftp) are vaguely smart about not transferring > duplicate files... > Well, that's how my Manuals script creates the index. It's written in Perl, and if I am going to write anything to do this, I am tempted to put Perl on my Windows machine and do it in Perl, I already have the script :-) Beats anything else (that I am familiar with) for that kind of work. I would just match filenames and filesize, time stamps don't mean anything. Thanks for the suggestions. Didier From hmurray at megapathdsl.net Fri Aug 22 22:08:19 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Fri, 22 Aug 2008 19:08:19 -0700 Subject: [time-nuts] file synchronization via ftp In-Reply-To: Message from "Didier Juges" of "Fri, 22 Aug 2008 19:37:34 CDT." <007a01c904b8$708b9820$0a01a8c0@didierhp> Message-ID: <20080823020820.0B084BCD0@ip-64-139-1-69.sjc.megapath.net> > I would just match filenames and filesize, time stamps don't mean anything. That won't catch a lot of edits that fix simple things like typos. Or the edit I just made that changed a parameter from 4 to 8. Are you trying to use the web site as serious backup storage, or just keep a (small) set of files out there where others can get them? If I was trying to keep a mirror on a web site up to date, I'd write a script to copy everything out there and run it whenever I added or updated something. That's assuming that you don't delete things. For deletes, I'd probably do them by hand until I had done enough of them to get annoyed and/or figure out what I wanted to do. -- These are my opinions, not necessarily my employer's. I hate spam. From didier at cox.net Fri Aug 22 22:24:50 2008 From: didier at cox.net (Didier Juges) Date: Fri, 22 Aug 2008 21:24:50 -0500 Subject: [time-nuts] file synchronization via ftp In-Reply-To: <20080823020820.0B084BCD0@ip-64-139-1-69.sjc.megapath.net> References: Message from "Didier Juges" of "Fri, 22 Aug 2008 19:37:34 CDT." <007a01c904b8$708b9820$0a01a8c0@didierhp> <20080823020820.0B084BCD0@ip-64-139-1-69.sjc.megapath.net> Message-ID: <008001c904c7$6c754ec0$0a01a8c0@didierhp> This is for my manuals. The primary storage is the web site, the local hard drive is the main backup and working copy, and I have a second backup on a USB drive. I want the same content at all 3 places. I also have a second backup web site, but I assume this one will just be a slave, updated when convenient. I am aware that at the moment I have a number of files that have slightly different names between the web site and the local hard drive (spaces replaced with underscores, filenames prefixed with manufacturer's name and such). I realize I will have to clean those by hand. I already have a tool running on the PC that does the bulk of that for me. I intend to identify duplicates by sorting all files (local and ftp) by size. The files of same size will be listed next to each other. The full path will tell me which is which, hopefully the names should not be so different that I could tell the duplicates, and if the name needs to be updated. Typically I don't delete anything, but I sometimes move things around. Hopefully when this is fully stabilized, there won't be much moving, I will upload new manuals directly where I want them. I cannot just copy 25 GB of stuff via ftp just to see if anything has changed. My main concern at the moment is to make sure I don't accidentally delete a file that would be only at one place. Hopefully, as my personal situation is finally stabilizing, I should be able to dedicate more time to this in the near future. Unfortunately, I have accumulated a bit of backlog lately (hi Abdul :-) I should develop a procedure, then make sure I have the tools to support it, and then it should be easy :-) Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray > Sent: Friday, August 22, 2008 9:08 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] file synchronization via ftp > > > I would just match filenames and filesize, time stamps > don't mean anything. > > That won't catch a lot of edits that fix simple things like typos. > > Or the edit I just made that changed a parameter from 4 to 8. > > > Are you trying to use the web site as serious backup storage, > or just keep a (small) set of files out there where others > can get them? > > If I was trying to keep a mirror on a web site up to date, > I'd write a script to copy everything out there and run it > whenever I added or updated something. > > That's assuming that you don't delete things. For deletes, > I'd probably do them by hand until I had done enough of them > to get annoyed and/or figure out what I wanted to do. > > > > > -- > 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 max at maxsmusicplace.com Fri Aug 22 23:01:18 2008 From: max at maxsmusicplace.com (Max Robinson) Date: Fri, 22 Aug 2008 22:01:18 -0500 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <805296.17410.qm@web96101.mail.aue.yahoo.com> Message-ID: <01d901c904cc$83ce88c0$6401a8c0@BACKROOM> Well, I won't cross that bridge until I am forced to. 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: "Bruce Griffiths" To: "Discussion of precise time and frequency measurement" Sent: Friday, August 22, 2008 12:28 AM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > Max > > A capacitance bridge using a transformer would be a lot more stable than > merely using the capacitance to vary the frequency of an LC oscillator. > > The advantage of a capacitive sensing technique over a light beam is that > it has much simpler and potentially more stable mechanical system than > when a the mercury colum interrupts a light beam. Unless of course on has > the Mercury column move a moire grating or similar setup such as making > the top of the mercury column a reflector in an interferometer system. > > 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 k1ggi at arrl.net Fri Aug 22 23:14:18 2008 From: k1ggi at arrl.net (Ed, k1ggi) Date: Fri, 22 Aug 2008 23:14:18 -0400 Subject: [time-nuts] Time Nuts at Boxboro In-Reply-To: References: Message-ID: <021801c904ce$54af2bb0$0a01a8c0@ATHLONXP1700> Yes. Careful not to get trampled in the stampede. 73, Ed, k1ggi -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Scott McGrath Sent: Friday, August 22, 2008 1:36 PM To: time-nuts at febo.com Subject: [time-nuts] Time Nuts at Boxboro Anyone going to to the ARRL Regional convention in Boxborough MA this weekend? _______________________________________________ time-nuts mailing list -- 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 fortime at bellsouth.net Fri Aug 22 23:15:22 2008 From: fortime at bellsouth.net (phil) Date: Fri, 22 Aug 2008 23:15:22 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> Message-ID: <005f01c904ce$7b9b7710$a101a8c0@officemail> ----- Original Message ----- From: "Magnus Danielson" To: "Discussion of precise time and frequency measurement" Sent: Friday, August 22, 2008 5:25 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > phil wrote: >> Gentlemen, >> Original poster is trying to "RESTORE" this entire old General Radio >> Standard ( a rack of equipment) to it's "original" glory. >> He simply needs a part, a unique thermoswitch or a way to fix it, not >> retrofit an atomic engine! This is a museum class instrument, 100kc. >> >> May I suggest start a new thread on the better/best merits/design of >> temperature control. >> Makes it rather difficult to follow a thread as the subject has changed. > > My proposal to use capacitive sensing rather than conductive sensing > would handle the electrode oxide issue. It is meant as a means to go > around the sensing issue with parts at hand and only some new electronic > design of very simple form, not the means to supercalibrate something. > > I guess this only shows that time-nuts are time-nuts... > > Cheers, > Magnus Magnus, Perhaps this will help understand why I made that comment. That old "primary" standard was quite a contraption. This things heyday was in the order of 1950's and used up into the 60's and some models into early 70's. Of course it was all tube equipment. My unit model was possibly a 620, it predated what Russ has (1100) but was quite similar in design. Russ's unit has all the multivibrators in one housing where mine was each separate. I think his is a 100kc oscillator and mine was 50kc. As I remember the one I had was in two 7-foot racks, a standard side and frequency measuring side. My oscillator was 50KC though about 300 dollars in the mid 6o's would have bought a 100kc quartz bar to upgrade it The unit had each module or circuit in a separate 19" rack space all averaging 8 inch high The main components, a power supply, oscillator (about 20 plus rack inches high by itself), separate multivibrators of 100kc, 10kc, 1kc, and 100 cycles. Yes they were called multivibrators though all tube. It also had a syncronometer at the top of the rack, better known as a clock. Apparently the crystal was rich in harmonics and they made use of it in this assembly. That clock ran off of the 1 kc output. The heart of the oscillator, main part of this contraption used a quartz bar about 3/8 of an inch square and about 2 inches long suspended on 4 springs. If I recall it was a single oven but it's specs called for about .01-degree regulation. I don't remember all the fine details, but it had many other components (all seperate rack units), a separate 5kc interpolation oscillator, amplifier, and even an 8-inch speaker to zero beat the standard to another unit, talking about phase lock! So as you can see, these vintage units only use/value is that of an antique or conversation piece. A 10811 would blow it away performance wise. Now with an understanding of that old antique, that discussion was like putting an electronic ignition in place of the old Ford Model T spark coil. You could, but .. You just search for the part. So it's not a "time-nut" issue as such other than appreciating the history or the evolution of time. I can see from the varied posts this is one heck of a super talented group. I guess we all get involved in something interesting and easily get carried away, as in the discussion. Granted you can do a given task many ways, and bantering ideas around is how things are born and perfected. Only problem is, it doesn't locate an "original" antique part, what he stated he wanted! That old GR stuff does occasionally show up, most free to haul off it's so massive. A bunch of the old vintage GR standard parts was listed as a lot on ebay some months ago. Someone asked what happened to my old GR stuff. I disposed of over 100 tons of old electronics that had accumulated including this old GR stuff. One of my sidelines was the used equipment business and the sales of tube stuff died. I had some 15,000 feet of "junk" as I call all this stuff. By the way, according to Bruce, that design of the old "thermoswitch" achieved resolutions as fine as .001 degrees. It would be hard to build any electronic sensor of any design that is that reliable and repeatable (.001 degree) with a "one-time" factory calibration good for a life exceeding 50 years without using a similar sensor design. The unit in question with the electrode in mercury design lasted about 50 years before showing it's age and misbehaving. Phil From rvassar at rob-vassar.com Fri Aug 22 23:38:05 2008 From: rvassar at rob-vassar.com (Robert Vassar) Date: Fri, 22 Aug 2008 22:38:05 -0500 Subject: [time-nuts] file synchronization via ftp In-Reply-To: <008001c904c7$6c754ec0$0a01a8c0@didierhp> References: Message from "Didier Juges" of "Fri, 22 Aug 2008 19:37:34 CDT." <007a01c904b8$708b9820$0a01a8c0@didierhp> <20080823020820.0B084BCD0@ip-64-139-1-69.sjc.megapath.net> <008001c904c7$6c754ec0$0a01a8c0@didierhp> Message-ID: <0905CE5D-C710-46E4-A445-45D63DD335A8@rob-vassar.com> You can get rsync to run on Windows under Cygwin. This may help: http://optics.ph.unimelb.edu.au/help/rsync/rsync_pc1.html The heavy weight option might be to go to www.virtualbox.org, download the free version, and run a virtualized Linux instance in a container on your windows machine and rsync from there. (Disclaimer: I work for their parent company.) Another solution would be to run the Linux equivalent of "ufsdump", and download the delta. Something like "ssh root at foo 'ufsdump [0-9] - f - ' >local.dumpfile" or something similar. Try "man -k dump". Rob KC6OOM/5 On Aug 22, 2008, at 9:24 PM, Didier Juges wrote: > This is for my manuals. The primary storage is the web site, the > local hard > drive is the main backup and working copy, and I have a second > backup on a > USB drive. I want the same content at all 3 places. I also have a > second > backup web site, but I assume this one will just be a slave, > updated when > convenient. > > I am aware that at the moment I have a number of files that have > slightly > different names between the web site and the local hard drive (spaces > replaced with underscores, filenames prefixed with manufacturer's > name and > such). I realize I will have to clean those by hand. I already have > a tool > running on the PC that does the bulk of that for me. > > I intend to identify duplicates by sorting all files (local and > ftp) by > size. The files of same size will be listed next to each other. The > full > path will tell me which is which, hopefully the names should not be so > different that I could tell the duplicates, and if the name needs > to be > updated. > > Typically I don't delete anything, but I sometimes move things around. > Hopefully when this is fully stabilized, there won't be much > moving, I will > upload new manuals directly where I want them. > > I cannot just copy 25 GB of stuff via ftp just to see if anything has > changed. > > My main concern at the moment is to make sure I don't accidentally > delete a > file that would be only at one place. > > Hopefully, as my personal situation is finally stabilizing, I > should be able > to dedicate more time to this in the near future. Unfortunately, I > have > accumulated a bit of backlog lately (hi Abdul :-) > > I should develop a procedure, then make sure I have the tools to > support it, > and then it should be easy :-) > > Didier KO4BB > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Hal Murray >> Sent: Friday, August 22, 2008 9:08 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] file synchronization via ftp >> >>> I would just match filenames and filesize, time stamps >> don't mean anything. >> >> That won't catch a lot of edits that fix simple things like typos. >> >> Or the edit I just made that changed a parameter from 4 to 8. >> >> >> Are you trying to use the web site as serious backup storage, >> or just keep a (small) set of files out there where others >> can get them? >> >> If I was trying to keep a mirror on a web site up to date, >> I'd write a script to copy everything out there and run it >> whenever I added or updated something. >> >> That's assuming that you don't delete things. For deletes, >> I'd probably do them by hand until I had done enough of them >> to get annoyed and/or figure out what I wanted to do. >> >> >> >> >> -- >> 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 rvassar at rob-vassar.com Fri Aug 22 23:47:12 2008 From: rvassar at rob-vassar.com (Robert Vassar) Date: Fri, 22 Aug 2008 22:47:12 -0500 Subject: [time-nuts] While we're discussing backups... Message-ID: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> Just a quick thought. I saw at least one person mention RAID, and another mention multiple copies of the same data. A true backup copy is off line. RAID does not protect you from an accidental delete, virus, etc... Multiple copies only spreads the risk around. I backup to a USB hard disk. I plug it in, backup, unplug it, de- cable and park it in a filing cabinet. The disk spends 99.99% of it's life powered off. It should last a decade or more like this, but I buy a new disk to replace it every 5 years, regardless if it needs it or not. Really critical stuff goes on a CD-R, stored flat in a jewel case, and goes in the safe deposit box. Rob KC6OOM/5 From max at maxsmusicplace.com Sat Aug 23 01:19:39 2008 From: max at maxsmusicplace.com (Max Robinson) Date: Sat, 23 Aug 2008 00:19:39 -0500 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail><48AF2ECB.7040506@rubidium.dyndns.org> <005f01c904ce$7b9b7710$a101a8c0@officemail> Message-ID: <002901c904df$d7d4b7b0$6401a8c0@BACKROOM> There must have been several different versions of this unit. The oscillator I have is 5 MHz. The frequency dividers in the rack I got it out of were discrete transistor construction. Seems to me the clock used a 25L6 although I don't remember how they derived the heater voltage. There was also a phase locked frequency multiplier with outputs at 10 MHz, 100 MHz and 1 GHz. The frequency divider module had outputs down to 1 PPS. After typing that I'm not sure the oscillator frequency is right. Maybe it's 1 MHz. I'm sure it's not 100 kHz. 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: "phil" To: "Discussion of precise time and frequency measurement" Sent: Friday, August 22, 2008 10:15 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > ----- Original Message ----- > From: "Magnus Danielson" > To: "Discussion of precise time and frequency measurement" > > Sent: Friday, August 22, 2008 5:25 PM > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > >> phil wrote: >>> Gentlemen, >>> Original poster is trying to "RESTORE" this entire old General Radio >>> Standard ( a rack of equipment) to it's "original" glory. >>> He simply needs a part, a unique thermoswitch or a way to fix it, not >>> retrofit an atomic engine! This is a museum class instrument, 100kc. >>> >>> May I suggest start a new thread on the better/best merits/design of >>> temperature control. >>> Makes it rather difficult to follow a thread as the subject has changed. >> >> My proposal to use capacitive sensing rather than conductive sensing >> would handle the electrode oxide issue. It is meant as a means to go >> around the sensing issue with parts at hand and only some new electronic >> design of very simple form, not the means to supercalibrate something. >> >> I guess this only shows that time-nuts are time-nuts... >> >> Cheers, >> Magnus > > > Magnus, > Perhaps this will help understand why I made that comment. > > That old "primary" standard was quite a contraption. This things heyday > was > in the order of 1950's and used up into the 60's and some models into > early > 70's. Of course it was all tube equipment. > > My unit model was possibly a 620, it predated what Russ has (1100) but was > quite similar in design. Russ's unit has all the multivibrators in one > housing where mine was each separate. I think his is a 100kc oscillator > and > mine was 50kc. > > As I remember the one I had was in two 7-foot racks, a standard side and > frequency measuring side. My oscillator was 50KC though about 300 dollars > in > the mid 6o's would have bought a 100kc quartz bar to upgrade it > > The unit had each module or circuit in a separate 19" rack space all > averaging 8 inch high The main components, a power supply, oscillator > (about > 20 plus rack inches high by itself), separate multivibrators of 100kc, > 10kc, > 1kc, and 100 cycles. Yes they were called multivibrators though all tube. > It > also had a syncronometer at the top of the rack, better known as a clock. > Apparently the crystal was rich in harmonics and they made use of it in > this > assembly. That clock ran off of the 1 kc output. > > The heart of the oscillator, main part of this contraption used a quartz > bar > about 3/8 of an inch square and about 2 inches long suspended on 4 > springs. > If I recall it was a single oven but it's specs called for about > .01-degree > regulation. > > I don't remember all the fine details, but it had many other components > (all > seperate rack units), a separate 5kc interpolation oscillator, amplifier, > and even an 8-inch speaker to zero beat the standard to another unit, > talking about phase lock! > > So as you can see, these vintage units only use/value is that of an > antique > or conversation piece. A 10811 would blow it away performance wise. > > Now with an understanding of that old antique, that discussion was like > putting an electronic ignition in place of the old Ford Model T spark > coil. > You could, but .. You just search for the part. > > So it's not a "time-nut" issue as such other than appreciating the history > or the evolution of time. I can see from the varied posts this is one heck > of a super talented group. I guess we all get involved in something > interesting and easily get carried away, as in the discussion. Granted you > can do a given task many ways, and bantering ideas around is how things > are > born and perfected. Only problem is, it doesn't locate an "original" > antique > part, what he stated he wanted! > > That old GR stuff does occasionally show up, most free to haul off it's so > massive. A bunch of the old vintage GR standard parts was listed as a lot > on > ebay some months ago. > > Someone asked what happened to my old GR stuff. I disposed of over 100 > tons > of old electronics that had accumulated including this old GR stuff. One > of > my sidelines was the used equipment business and the sales of tube stuff > died. I had some 15,000 feet of "junk" as I call all this stuff. > > By the way, according to Bruce, that design of the old "thermoswitch" > achieved resolutions as fine as .001 degrees. > > It would be hard to build any electronic sensor of any design that is that > reliable and repeatable (.001 degree) with a "one-time" factory > calibration > good for a life exceeding 50 years without using a similar sensor design. > The unit in question with the electrode in mercury design lasted about 50 > years before showing it's age and misbehaving. > > Phil > > > > _______________________________________________ > time-nuts mailing list -- 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 Sat Aug 23 03:57:53 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Sat, 23 Aug 2008 03:57:53 -0400 Subject: [time-nuts] Capacitive temperature sensing References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AF4D35.205@xtra.co.nz> Message-ID: (I combined your two posts into one) > Mike > The RV Jones papers were published in either the Review of > Scientific instruments or the Journal of Sceintific Instruments - > I forget which. > I'll look for my paper copies when I get back from shopping later > today. > Sydenham also wrote at least one paper on various capacitive > displacement sensors. > Physik Instrumente use capacitive displacement sensors with > nanometer sensitivity in their piezostages and piezoactuators. > Bruce > You could also look at Queensgate Instruments. > Integral capacitive sensors have been used in a feedback loop to > maintain the spacing and parallelism of a pair of Fabry-Perot > interferometer plates. > Bruce Hi Bruce, Thanks for the info. I looked at Physik Instrumente, and their performance is truly impressive. For example, the D-510.020 single-electrode capacitive sensor has a nominal range of 20 um, and a sensor active area of 11.2 mm^2: http://www.physikinstrumente.com/en/pdf/D510_Datasheet.pdf According to my calculations, that works out to a capacitance of about 4.95 pf. They show a resolution for this sensor of <0.001%, which is 20e-6 * 0.001 * 0.01 * 1e9 = 0.2 nm. The change in capacitance is 4.95 * 0.001 * 0.01 = 0.0000495pf, which is quite amazing. That is a very small change. If the nominal sensor voltage was 1 volt, this represents a change of 1 * 0.001 * 0.01 = 0.00001 Volt, or 10 uV, which is quite acceptable for good S/N. One problem might be long-term drift. The temperature coefficients and other errors are in the hundreds of ppm, whereas the tolerance in interferometry are down to 0.1 ppm. It is interesting to note they use Zygo ZMI-2000 and ZMI-1000 laser interferometers in their calibration labs, presumably for long-term accuracy: http://www.physikinstrumente.com/en/products/nanopositioning/test_calibration.php Also, they use flat plate capacitors in the sensors. I don't know how well this would work on a thin column of mercury surrounded by a glass dielectric. But this is new information to me, and I am quite impressed with the performance. Thank you for posting the information. Regards, Mike Monett From bruce.griffiths at xtra.co.nz Sat Aug 23 04:54:42 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 20:54:42 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: <48AF4D35.205@xtra.co.nz> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AF4D35.205@xtra.co.nz> Message-ID: <48AFD052.4050309@xtra.co.nz> Mike One good general reference for capacitance micrometers is: /Microdisplacement Transducers/ by P.H. Sydenham, Journal of Physics E, Scientific Instruments, Vol 5, p721-33, 1972. It seems that capacitance micrometers can be 3 orders of magnitude more sensitive than I stated i.e. they can detect displacements of about 1E-14 m. This compares well with interferometry which can detect displacements of around 1E-10 m. RV Jones was at the University of Aberdeen not Glasgow. RV Jones was the first recipient of the CIA's RV Jones Intelligence award: http://www.royalsoced.org.uk/fellowship/obits/obits_alpha/jones_reginald.pdf http://www.iop.org/EJ/abstract/0022-3735/6/7/001/ Bruce From bruce.griffiths at xtra.co.nz Sat Aug 23 05:04:11 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 21:04:11 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AF4D35.205@xtra.co.nz> Message-ID: <48AFD28B.5090105@xtra.co.nz> Mike Monett wrote: > Hi Bruce, > > Thanks for the info. I looked at Physik Instrumente, and their > performance is truly impressive. For example, the D-510.020 > single-electrode capacitive sensor has a nominal range of 20 um, and > a sensor active area of 11.2 mm^2: > > http://www.physikinstrumente.com/en/pdf/D510_Datasheet.pdf > > According to my calculations, that works out to a capacitance of > about 4.95 pf. > > They show a resolution for this sensor of <0.001%, which is 20e-6 * > 0.001 * 0.01 * 1e9 = 0.2 nm. > > The change in capacitance is 4.95 * 0.001 * 0.01 = 0.0000495pf, > which is quite amazing. That is a very small change. > > If the nominal sensor voltage was 1 volt, this represents a change > of 1 * 0.001 * 0.01 = 0.00001 Volt, or 10 uV, which is quite > acceptable for good S/N. > > One problem might be long-term drift. The temperature coefficients > and other errors are in the hundreds of ppm, whereas the tolerance > in interferometry are down to 0.1 ppm. > > It is interesting to note they use Zygo ZMI-2000 and ZMI-1000 laser > interferometers in their calibration labs, presumably for long-term > accuracy: > > > http://www.physikinstrumente.com/en/products/nanopositioning/test_calibration.php > > Also, they use flat plate capacitors in the sensors. I don't know > how well this would work on a thin column of mercury surrounded by a > glass dielectric. > > But this is new information to me, and I am quite impressed with the > performance. Thank you for posting the information. > > Regards, > > Mike Monett > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > Mike One technique would be to use the mercury column as the central plate of a differential capacitor. Alternatively use a large cylindrical sleeve to make a high capacitance connection to the mercury column and use a position sensing cylindrical sleeve surrounding the set point. Temperature compensation can be achieved by using a reference capacitor of similar construction by metal coating the bore of a similar glass capillary. Since this is a fixed setpoint device it need not have a large dynamic range. Thus a tempco of 100ppm need not be an issue if the range is small enough and the reference capacitor shares the same tightly regulated thermal environment. Cylindrical geometry variable capacitors can be made to work quite well, Syndenham covers this as well as the parallel plate variety. Bruce From XDE-L2G3 at myamail.com Sat Aug 23 05:44:42 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Sat, 23 Aug 2008 05:44:42 -0400 Subject: [time-nuts] Capacitive temperature sensing References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AF4D35.205@xtra.co.nz> <48AFD052.4050309@xtra.co.nz> Message-ID: Bruce Griffiths wrote: >Mike > One good general reference for capacitance micrometers is: > /Microdisplacement Transducers/ by P.H. Sydenham, Journal of > Physics E, Scientific Instruments, Vol 5, p721-33, 1972. > > It seems that capacitance micrometers can be 3 orders of magnitude > more sensitive than I stated i.e. they can detect displacements of > about 1E-14 m. > This compares well with interferometry which can detect > displacements of around 1E-10 m. > RV Jones was at the University of Aberdeen not Glasgow. > RV Jones was the first recipient of the CIA's RV Jones > Intelligence award: >http://www.royalsoced.org.uk/fellowship/obits/obits_alpha/jones_reginald.pdf >http://www.iop.org/EJ/abstract/0022-3735/6/7/001/ > Bruce Hi Bruce, Thanks very much for the url. That is a very interesting article on Jones. Nice to have an award named after you, and to be the first one to receive it:) The abstract for his article states: "A general account is given of both the electrical and the mechanical aspects of the design of capacitive transducers and their associated electronic circuitry suitable for observing displacements of the order 10-2 to 10-11 mm. The lower figure is the order of magnitude of noise and drift averaged over a second, the drift over a day of the order 10-8 to 10-9 mm. Their application is illustrated by descriptions of an apparatus to explore the limits of performance, a moderately sensitive micrometer, and two geophysical instruments, a tiltmeter and a gravimeter. Full details of a general purpose electronic system are given." That article, and "Microdisplacement Transducers" by Sydenham both cost $80.00 USD. That's a bit high. It's a shame they have to charge so much, when the internet has reduced the distribution cost to nearly zero. It's not very useful to claim a resolution of 10-11mm when that is the magnitude of noise and drift averaged over a second. The drift of 10-9mm per day is more realistic, but I'd really like to see the drift expected per year. Probably the capacitive sensor has the best application in measuring dynamic issues such as the roundness of rotating shafts, tiltmeters, and other areas where interferometry is difficult or cannot be used. But for short-term measurements, it looks very good. Thanks for the info! Best Regards, Mike Monett From bruce.griffiths at xtra.co.nz Sat Aug 23 06:09:43 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 22:09:43 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AF4D35.205@xtra.co.nz> <48AFD052.4050309@xtra.co.nz> Message-ID: <48AFE1E7.4050106@xtra.co.nz> Mike Monett wrote: > Hi Bruce, > > Thanks very much for the url. That is a very interesting article on > Jones. Nice to have an award named after you, and to be the first > one to receive it:) > > The abstract for his article states: > > "A general account is given of both the electrical and the > mechanical aspects of the design of capacitive transducers and their > associated electronic circuitry suitable for observing displacements > of the order 10-2 to 10-11 mm. The lower figure is the order of > magnitude of noise and drift averaged over a second, the drift over > a day of the order 10-8 to 10-9 mm. Their application is illustrated > by descriptions of an apparatus to explore the limits of > performance, a moderately sensitive micrometer, and two geophysical > instruments, a tiltmeter and a gravimeter. Full details of a general > purpose electronic system are given." > > That article, and "Microdisplacement Transducers" by Sydenham both > cost $80.00 USD. That's a bit high. It's a shame they have to charge > so much, when the internet has reduced the distribution cost to > nearly zero. > > It's not very useful to claim a resolution of 10-11mm when that is > the magnitude of noise and drift averaged over a second. The drift > of 10-9mm per day is more realistic, but I'd really like to see the > drift expected per year. > > Probably the capacitive sensor has the best application in measuring > dynamic issues such as the roundness of rotating shafts, tiltmeters, > and other areas where interferometry is difficult or cannot be used. > > But for short-term measurements, it looks very good. Thanks for the > info! > > Best Regards, > > Mike Monett > Mike The drifts experienced were all due to mechanical instabilities which would affect an interferometer sensing the position of the sensor mass in exactly the same way. Jones used mica insulators, phosphor bronze and brass to construct his instruments. He also took great care to isolate the sensitive parts of the instrument from undesired variable external forces to minimise distortion. With more stable materials and better mechanical design such as using fused silica parts or etching the entire instrument from single crystal silicon much higher stability is possible. I obtained my copies the old way from the university library well before the advent of the Internet. Bruce From t_list_1_only at braw.co.uk Sat Aug 23 06:21:26 2008 From: t_list_1_only at braw.co.uk (David ) Date: Sat, 23 Aug 2008 11:21:26 +0100 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: Message-ID: <86AAAE2525694079BA885B809D66BCC8@hp6110> Bruce, A totally trivial correction for you : "the work of RV Jones at the university of Glasgow in the 50's, 60's and 70's. " Jones was at Aberdeen university post war. A curious character, his recollections of his wartime research are fascinating and worth reading but I fear are best read with care alongside some other histories to maintain balance. Regards David > -----Original Message----- > Hej Magnus > > A capacitive sensing AC bridge can be very sensitive, one only has to > look at the work of RV Jones at the university of Glasgow in > the 50's, > 60's and 70's. He and his collaborators used capacitive sensors to > detect (among other things) the extrusion of a micrometer shaft as it > was clamped to realise just how sensitive it can be. > They found it possible to detect length changes of less than > 1E-11m with > a suitably designed sensor. > > Even more sensitive capacitance bridge displacement sensors > have since > been constructed. Off course the critical bridge components > have to be > maintained at a reasonably constant temperature. Since the > most critical > component the balancing capacitor in the other bridge arm can be very > small it can easily be located in the same controlled temperature > environment as the sensor itself. One of the major contributors to > instability will be creep in the glass capillary and bulb dimensions. > Even with a relatively crude guard ringed coaxial sensor electrode > surrounding a capillary tube is capable of submicron > sensitivity without > undue effort. > > If one uses a mercury in glass thermometer with say 0.1C > resolution with > the 0.1C graduation say 0.5mm apart then 1micron change in mercury > column length is equivalent to a temperature change of 200uK. The > performance will be determined largely by mechanical > instabilities not > the bridge sensitivity. > > Bruce From bruce.griffiths at xtra.co.nz Sat Aug 23 06:29:17 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 22:29:17 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: <86AAAE2525694079BA885B809D66BCC8@hp6110> References: <86AAAE2525694079BA885B809D66BCC8@hp6110> Message-ID: <48AFE67D.2050607@xtra.co.nz> David wrote: > Bruce, > > A totally trivial correction for you : > "the work of RV Jones at the university of Glasgow in the 50's, 60's and > 70's. " > > Jones was at Aberdeen university post war. A curious character, his > recollections of his wartime research are fascinating and worth reading but > I fear are best read with care alongside some other histories to maintain > balance. > > Regards > David > David The Royal Society Obituary was a somewhat toned down version of his attitude to some other disciplines (such as Social Sciences) as related to me by a Social Science graduate of the University of Aberdeen in 1985. Bruce From magnus at rubidium.dyndns.org Sat Aug 23 06:32:15 2008 From: magnus at rubidium.dyndns.org (Magnus Danielson) Date: Sat, 23 Aug 2008 12:32:15 +0200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: <48AF3A72.5090502@xtra.co.nz> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> Message-ID: <48AFE72F.1010706@rubidium.dyndns.org> Hej Bruce, > Hej Magnus > > A capacitive sensing AC bridge can be very sensitive, one only has to > look at the work of RV Jones at the university of Glasgow in the 50's, > 60's and 70's. He and his collaborators used capacitive sensors to > detect (among other things) the extrusion of a micrometer shaft as it > was clamped to realise just how sensitive it can be. > They found it possible to detect length changes of less than 1E-11m with > a suitably designed sensor. Indeed. However, I was trying to hint on a alternative approach or temporary approach which would not need much design to achieve equal performance if the electrodes could not be cleaned or replaced easilly. I trust the capacitive measurement would be sufficiently good even at moderate design efforts. Cheers, Magnus From bruce.griffiths at xtra.co.nz Sat Aug 23 06:45:57 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 22:45:57 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: <48AFE72F.1010706@rubidium.dyndns.org> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AFE72F.1010706@rubidium.dyndns.org> Message-ID: <48AFEA65.1030108@xtra.co.nz> Magnus Danielson wrote: > Hej Bruce, > > >> Hej Magnus >> >> A capacitive sensing AC bridge can be very sensitive, one only has to >> look at the work of RV Jones at the university of Glasgow in the 50's, >> 60's and 70's. He and his collaborators used capacitive sensors to >> detect (among other things) the extrusion of a micrometer shaft as it >> was clamped to realise just how sensitive it can be. >> They found it possible to detect length changes of less than 1E-11m with >> a suitably designed sensor. >> > > Indeed. However, I was trying to hint on a alternative approach or > temporary approach which would not need much design to achieve equal > performance if the electrodes could not be cleaned or replaced easilly. > > I trust the capacitive measurement would be sufficiently good even at > moderate design efforts. > > Cheers, > Magnus > > Hej Magnus The biggest problem is that a stainless steel thermoregulator and not a mercury in glass one may have been used. Retrofitting temporary capacitive sensing would be difficult to impossible in this case. Metals other than platinum or iron are precluded from use as they tend to form amalgams with the mercury. However one could probably temporarily substitute a mercury in glass thermometer with capacitive position sensing. The only potential problem being that there are moves afoot to ban mercury thermometers. A capacitance of around 1pF or so may be expected for a 1cm long cylindical capacitive sensor electrode and an instability in the capacitance measurement of 100ppm or so would be required to achieve millidegree stability (provided the mechanical instability of the glass allows this). Bruce From bruce.griffiths at xtra.co.nz Sat Aug 23 06:57:35 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Sat, 23 Aug 2008 22:57:35 +1200 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: <48AFE72F.1010706@rubidium.dyndns.org> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AFE72F.1010706@rubidium.dyndns.org> Message-ID: <48AFED1F.3050809@xtra.co.nz> Hej Magnus An elegant way of achieving some degree of temperature compensation may be to use 3 coaxial electrodes surrounding the mercury column. One relatively long one used to couple the bridge drive signal to the mercury column and located between the other 2. The top electrode one being used to sense the position of the tip of the mercury column and the lower one as a temperature compensation element in the other side of the bridge. A phase sensitive detector with a suitable preamp could be used to detect a capacitive null. The phase sensitive detector output drives a PID or other temperature control system. Bruce From bob.paddock at gmail.com Sat Aug 23 09:58:55 2008 From: bob.paddock at gmail.com (Bob Paddock) Date: Sat, 23 Aug 2008 09:58:55 -0400 Subject: [time-nuts] Capacitive temperature sensing In-Reply-To: References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <48AF3A72.5090502@xtra.co.nz> Message-ID: <200808230958.55311.bob.paddock@gmail.com> > Bruce, very interesting. I didn't know capacitive sensors went down > that low. That could be useful in other areas. > > I searched google but found nothing. Do you have any urls? http://www.eetimes.com/showArticle.jhtml?articleID=175801455 "EE Times: SENSORS: Quake detector preps for market ... "We are finishing the prototype now," said Les LeZar, president of Zoltech (Van Nuys, Calif.). "As it stands, its case is just under 2 feet tall and houses an 18-inch pendulum." Peters' design uses a novel means of varying the surface area of a capacitor. Rather than varying its gap as in standard capacitive sensors, Peters' design varies the capacitor's surface area. Because the capacitor's gap is constant, detection is not accompanied by a drop-off in sensitivity, as is the case with other capacitive sensors. Most of those become less sensitive when their gap widens. "I have a patent on several variations of what I call a symmetric differential capacitive sensor ? what microelectromechanical-systems designers call 'fully differential,' " said Peters. Since sensitivity and dynamic range don't have to be treated as a design trade-off ? as in traditional capacitive sensors ? Peters' design sets sensitivity by the constant size of the gap. By changing the surface area, it separately determines dynamic range. In a nutshell, the dangling pendulum has a grounded Faraday shield on the end, hanging between the four plates of a symmetric differential capacitor wired in a diamond like a Wheatstone bridge, but with series diodes and parallel resistors to rectify its output into direct current. Parallel printed-circuit boards house the plates of four square capacitors. The grounded Faraday shield initially covers all capacitors equally. When the Faraday shield is jiggled, it increases the surface area of two capacitors on opposite sides of the bridge, and decreases the other two opposing capacitors' area, thereby giving the bridge its differential sensitivity. A 50-MHz signal is then pumped across two opposing capacitor leads in the bridge, while the differential inputs to the sensing operational amplifier are wired to the other two opposing capacitor leads. ..." -- http://www.wearablesmartsensors.com/ http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/ From XDE-L2G3 at myamail.com Sat Aug 23 11:09:32 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Sat, 23 Aug 2008 11:09:32 -0400 Subject: [time-nuts] Capacitive temperature sensing References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AF4D35.205@xtra.co.nz> <48AFD052.4050309@xtra.co.nz> <48AFE1E7.4050106@xtra.co.nz> Message-ID: Bruce Griffiths wrote: >Mike > The drifts experienced were all due to mechanical instabilities > which would affect an interferometer sensing the position of the > sensor mass in exactly the same way. > Jones used mica insulators, phosphor bronze and brass to construct > his instruments. > He also took great care to isolate the sensitive parts of the > instrument from undesired variable external forces to minimise > distortion. > With more stable materials and better mechanical design such as > using fused silica parts or etching the entire instrument from > single crystal silicon much higher stability is possible. [...] >Bruce Bruce, that might be a bit optimistic. There is electronic drift as well. Physik Instrumente talks about tolerances of several hundred ppm, and laser interferometers are a tenth of a ppm. The interferometer is three orders of magnitude more stable. This stands to reason since the interferometer is counting fringes. These are determined by the frequency of the light source, which can be measured and controlled better than any other physical parameter. Also, it is significant that Physik Instrumente uses Zygo ZMI-2000 and ZMI-1000 laser interferometers in their calibration labs, and not their own capacitive sensors. http://www.physikinstrumente.com/en/products/nanopositioning/test_calibration.php If there sensors were as good as an interferometer, they wouldn't need Zygo. Regards, Mike Monett From XDE-L2G3 at myamail.com Sat Aug 23 11:43:25 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Sat, 23 Aug 2008 11:43:25 -0400 Subject: [time-nuts] Capacitive temperature sensing References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AFE72F.1010706@rubidium.dyndns.org> <48AFEA65.1030108@xtra.co.nz> Message-ID: Bruce Griffiths wrote: > Magnus Danielson wrote: >> Hej Bruce, [...] >> Indeed. However, I was trying to hint on a alternative approach >> or temporary approach which would not need much design to achieve >> equal performance if the electrodes could not be cleaned or >> replaced easilly. >> I trust the capacitive measurement would be sufficiently good >> even at moderate design efforts. >> Cheers, >> Magnus >Hej Magnus > The biggest problem is that a stainless steel thermoregulator and > not a mercury in glass one may have been used. > Retrofitting temporary capacitive sensing would be difficult to > impossible in this case. > Metals other than platinum or iron are precluded from use as they > tend to form amalgams with the mercury. > However one could probably temporarily substitute a mercury in > glass thermometer with capacitive position sensing. > The only potential problem being that there are moves afoot to ban > mercury thermometers. > A capacitance of around 1pF or so may be expected for a 1cm long > cylindical capacitive sensor electrode and an instability in the > capacitance measurement of 100ppm or so would be required to > achieve millidegree stability (provided the mechanical instability > of the glass allows this). >Bruce Gentlemen, The problem is very simple. If the sensor lead that contacts the mercury has a diameter of 0.010 inch, with a flat end, and is 100 microinches away from the mercury, the capacitance is 0.35 pf. An Analog Devices AD7747 24-bit capacitance-to-digital converter could be used to measure this. It sells for $4.60 in quantity. It has a resolution of 20 aF (1e-18F), and an accuracy of 10 fF. This would allow it to detect a change in distance of 0.00566 microinch or 0.144 nanometers. This is on par with commercial capacitance sensors such as Physik Instrumente. But since it is completely integrated, the drift specifications are about an order of magnitude better. If the mercury contacts the sensor wire and shorts it to ground, a 7.5pF cap could be placed in series. This would limit the maximum capacitance to within the range of the AD7747. The AD7747 can accept up to 17pF of stray capacitance. The existing sensor wire should be much less than this, especially if the leads were as short as possible. The problem would be a bit more complicated if the sensor lead had a v-shaped end caused by cutting with pliers instead of the shearing action of scissors. But the resolution of the AD7747 should allow it to measure the capacitance just before making contact. It also has an on-board temperature sensor with an accuracy of 2 degrees C. This would allow the system to do coarse temperature measurements to confirm it was working. Regards, Mike Monett From XDE-L2G3 at myamail.com Sat Aug 23 12:35:00 2008 From: XDE-L2G3 at myamail.com (Mike Monett) Date: Sat, 23 Aug 2008 12:35:00 -0400 Subject: [time-nuts] Capacitive temperature sensing References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail> <48AF2ECB.7040506@rubidium.dyndns.org> <48AF3A72.5090502@xtra.co.nz> <48AFE72F.1010706@rubidium.dyndns.org> <48AFEA65.1030108@xtra.co.nz> Message-ID: "Mike Monett" wrote: [...] > Gentlemen, > The problem is very simple. If the sensor lead that contacts the > mercury has a diameter of 0.010 inch, with a flat end, and is 100 > microinches away from the mercury, the capacitance is 0.35 pf. Sorry, I used a bad formula for the area of a circle. The actual capacitance is 0.1767 pF, still well within the capability of the AD7747. Regards, Mike Monett From hartzell at gmail.com Sat Aug 23 13:40:18 2008 From: hartzell at gmail.com (Dave hartzell) Date: Sat, 23 Aug 2008 10:40:18 -0700 Subject: [time-nuts] Trimble GPS mouse antenna for TBolt... Message-ID: <1c096fd70808231040j64c51b42kbd24daeceacdf277@mail.gmail.com> Hi all, Halted has some very cheap Trimble magnetic mouse GPS antennas, for $3.95. I was able to get one to work with my Tbolt, simply by putting an F-connector on the cable. The mouse comes with a proprietary connector...not sure what the coax is. http://www.halted.com/commerce/catalog/product.jsp?product_id=20182&czuid=1219512849402 Dave AF6KD From quenbob5 at pacbell.net Sat Aug 23 15:27:34 2008 From: quenbob5 at pacbell.net (Bob Q) Date: Sat, 23 Aug 2008 12:27:34 -0700 Subject: [time-nuts] Trimble GPS mouse antenna for TBolt... References: <1c096fd70808231040j64c51b42kbd24daeceacdf277@mail.gmail.com> Message-ID: <000301c90556$4be5fda0$1801a8c0@BOBCEL1R7> I bought one too, just inside the door at Halted. I have it patched to a Rockwell Jupiter board and it seems to give about the same results as another active patch antenna I have connected to a Motorola Oncore board. Bob Q. ----- Original Message ----- From: "Dave hartzell" To: "Discussion of precise time and frequency measurement" Sent: Saturday, August 23, 2008 10:40 AM Subject: [time-nuts] Trimble GPS mouse antenna for TBolt... > Hi all, > > Halted has some very cheap Trimble magnetic mouse GPS antennas, for > $3.95. I was able to get one to work with my Tbolt, simply by putting > an F-connector on the cable. The mouse comes with a proprietary > connector...not sure what the coax is. > > http://www.halted.com/commerce/catalog/product.jsp?product_id=20182&czuid=1219512849402 > > Dave > AF6KD > > _______________________________________________ > time-nuts mailing list -- 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 Aug 23 16:55:05 2008 From: hmurray at megapathdsl.net (Hal Murray) Date: Sat, 23 Aug 2008 13:55:05 -0700 Subject: [time-nuts] Leap Second quirk, Another hanging bridge In-Reply-To: Message from "Chris Kuethe" of "Tue, 12 Aug 2008 17:38:07 PDT." <91981b3e0808121738q2931a9fbg239774f7f466662c@mail.gmail.com> Message-ID: <20080823205506.7286FBCD0@ip-64-139-1-69.sjc.megapath.net> >> Do you expect the ZDA message to be better synchronized than any of >> the others? > Yes. In SiRF receivers ZDA is specifically aligned to the second. I > just checked my copy of the manual I got with my BU-353, and Table 1-1 > NMEA Output Messages says "ZDA PPS timing message (synchronized to > PPS)." RMC is produced after the navigation solution is computed and > that does not happen in constant time. My documentation for ZDA says "Each message is output within a few hundred ms after the 1 PPS pulse..." I was hoping for something (much) better than that. I don't actually care about the offset, I can correct for a constant. It's the jitter/wander that I'd like to avoid. I finally got time to try it. The released ntpd doesn't support ZDA, but I hacked in some code. ZDA isn't any better than RMC. That's just an eyeball of a graph of the peerstats offset, not a formal mathematical analysis. It's still got roughly 100 ms of wander/jitter, probably more if I wait longer to collect more data. I don't see anything good enough to be worth any effort to investigate more. Another problem is that ZDA doesn't have a status field to tell you if the time is invalid because it isn't seeing enough satellites. It's also got the leap second bug. -- These are my opinions, not necessarily my employer's. I hate spam. From pico.2008 at sbcglobal.net Sat Aug 23 18:47:59 2008 From: pico.2008 at sbcglobal.net (Peter Putnam) Date: Sat, 23 Aug 2008 15:47:59 -0700 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <002901c904df$d7d4b7b0$6401a8c0@BACKROOM> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail><48AF2ECB.7040506@rubidium.dyndns.org> <005f01c904ce$7b9b7710$a101a8c0@officemail> <002901c904df$d7d4b7b0$6401a8c0@BACKROOM> Message-ID: <48B0939F.60808@sbcglobal.net> I've posted some General Radio notes and specifications on their Model 1115-B oscillator, hoping there might be some relevance to the Model 1120. Product specific information starts on page 8. http://www.ni6e.com/genrad/ Regards, Peter NI6E Max Robinson wrote: > There must have been several different versions of this unit. The > oscillator I have is 5 MHz. The frequency dividers in the rack I got it out > of were discrete transistor construction. Seems to me the clock used a 25L6 > although I don't remember how they derived the heater voltage. There was > also a phase locked frequency multiplier with outputs at 10 MHz, 100 MHz and > 1 GHz. The frequency divider module had outputs down to 1 PPS. > > After typing that I'm not sure the oscillator frequency is right. Maybe > it's 1 MHz. I'm sure it's not 100 kHz. > > Regards. > > Max. K 4 O D S. > > From jmiles at pop.net Sat Aug 23 19:20:27 2008 From: jmiles at pop.net (John Miles) Date: Sat, 23 Aug 2008 16:20:27 -0700 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <48B0939F.60808@sbcglobal.net> Message-ID: That's really cool. A steampunk phase-noise analyzer! -- john > > I've posted some General Radio notes and specifications on their Model > 1115-B oscillator, hoping there might be some relevance to the Model 1120. > > Product specific information starts on page 8. > > http://www.ni6e.com/genrad/ > > Regards, > Peter > NI6E > From cfharris at erols.com Sat Aug 23 20:54:04 2008 From: cfharris at erols.com (Chuck Harris) Date: Sat, 23 Aug 2008 20:54:04 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <48A6C9B5.8040607@quackers.net> References: <48A6C9B5.8040607@quackers.net> Message-ID: <48B0B12C.9020702@erols.com> wje wrote: > As the one who made the first comment about not liking the PIC, I'll > give you my reasons. Yes, they are philosophical, even religious. I'm > also distinguishing between microprocessors (this discussion) and other > variants, such as DSPs, FPLDs, etc. > > First, I've used a very large number of different micros over the years > for both 'real' work and my own purposes, starting with the Intel 8008 > before it was commercially released. I've used Intel, TI, Motorola, > Zilog, MOS Tech processors of multiple families, and yes, even PICs, all > with wildly varying architectures. These days, given modern development > tools, the architecture of a general-purpose micro really isn't > particularly relevant. It's functionality and support tools that are > important. I too have a list of micro's and mini's as rich as yours: PDP8, Univac 11XX, IBM360, PDP-11, 680XX, 8008, 8080, 8085, 8088, 8086, 80186, 80286, 80386, ... DSP-32, 1802, Z80, 8051, 6502,..., and many, many PIC's. And with the exception of the first 5, I have been paid to program them all. > Without a doubt, PIC made it possible for many hobbyists to put together > nice projects that they would not necessarily have been able to do > otherwise. My deep-seated revulsion comes from one source, and it's not > the architecture, the company, or the capabilities of the chips. It's > Basic, the language. Until relatively recently, PIC and Basic were > almost synonymous, at least for the masses. Ah, well, that explains it! Your knowledge of PIC's is incomplete. The BASIC PIC, known as the STAMP, was a simple program running on a PIC that showed off somethings that you could do with a PIC. It was not even a Microchip product. Parallax took a compiler they wrote, and programmed it on an early PIC, sold millions of them as the STAMP. For more information: http://www.parallax.com/tabid/295/Default.aspx I have never programmed a PIC in anything other than assembler, or C. The PIC architecture is a RISC machine. Its memory is split into DATA and CODE sections. The entire data section is treated as pages of registers. All of the I/O is treated as data locations in memory. It is dirt simple, having less than 40 instructions. It is easy to program a PIC in assembler, and using a cross-compiler, it is reasonably easy for a compiler to generate good PIC code. I have found that CCS's C compiler generates PIC code that is as good, or better than a talented human programmer can write. > I have both EE and CS degrees, and I work in both worlds. For me it is a BSEE and an MSEE. I design hardware and software for embedded systems. My MS was about 50/50 microwaves and computer architecture. In my humble > (but completely accurate and stable) opinion, Basic is not a programming > language. It's a tool of Satan designed to convince people that they are > programmers when they really should stick to their janitorial duties. > This is a subset of the general problem that everyone thinks they are > programmers, and usually think their code is perfect. But, that's a rant > for a different audience. Well, if you feel that way about BASIC, then you must really hate assembler. You can write good, or bad code in any language. BASIC is no exception. If you treat BASIC as what it was intended to be, it is just fine. It is a step above a pocket calculator, and should be used as such. In my opinion, no BASIC program should be written that is longer than 100 lines. > So, for me, given that there are some very good C development tools for > mainstream processors, and frequently they are free, I just don't use > PICs. As I mentioned earlier, I currently like the Motorola (I mean, > Freescale; these silly name changes are yet another rant) MC68HCxx line; > there's a wide choice of features and they can be flashed easily without > a complicated programmer. The 8-pin xx908QT4 is a buck and does a fine > job for many purposes, and most importantly, you can get a nice C > development environment for the line, which was originally from > CodeWarrior, for free. It also supports the entire line, from 8-bit to > 32-bit, and with builtin support for all of the various on-chip > 'peripherals'. That's cool, but do any of them make a 6 pin uC that has some 10 bit ADC's built in? Oh, and can get to better than 1% timing accuracy over the full industrial temperature range without a crystal? Oh, is it available for under a buck in small quantities? No? Darn! > Even now, I don't think Microchip provides a compiler that supports the > low-end chips, but I haven't checked lately. Not a valid complaint. CCS supports everything that Microchip makes, and their compiler costs around $100.. and it produces tight efficient code. Plus, their library has native functions to access every feature of the PIC. And as an added bonus, the windows version runs nicely under wine, and there is a linux version available too! > But, when you get right down to it, you really need to pick the proper > solution for your problem. If there was something the PICs provided that > I couldn't get elsewhere, I'd use them. Religion is fine, but getting > the job done is more important. As I said, show me a 6 pin mini SOIC that has a built in oscillator that is accurate to better than 1% over the industrial temperature range (and voltage), has a handful of 10 bit ADC's built in, and can have a software UART on every pin (but one), and can be easily programmed in C, and costs under a buck (for full industrial temperature range). > > BTW, for those that think you can't do anything with an 8-pin 8-bit > micro, I did one design that supports an LCD, a rotary encoder, a > Hall-effect sensor, and a button. At home, I use the same chip in every > light switch in my house to implement a self-tuning capacitance sense > switch. I even use a couple for a more time-nuts related tasks. One > provides loop control for my GPS/Rb/Quartz standard, and one is used as > a 555 timer replacement in my SmartClock->PC interface. (Ok, I was in a > hurry, needed a pulse stretcher, and I didn't have any 555's lying around) I don't use 555's anymore, PICS are available that do the job better, and faster, and with lower power consumption. And they are more stable frequency wise. -Chuck Harris From cfharris at erols.com Sat Aug 23 20:56:33 2008 From: cfharris at erols.com (Chuck Harris) Date: Sat, 23 Aug 2008 20:56:33 -0400 Subject: [time-nuts] I want a good micro-controller In-Reply-To: <72894FB3-2532-4596-B050-869E8B872E41@rob-vassar.com> References: <72894FB3-2532-4596-B050-869E8B872E41@rob-vassar.com> Message-ID: <48B0B1C1.1080709@erols.com> Robert Vassar wrote: > As a member of the "brain damaged by Basic" generation, I mostly > agree with Bill's comments regarding it's use. Yet I still keep the > public domain 8052AH-BASIC image in my '51 code directory, and have > fond memories of it's use. The PIC is not alone in propagating that > mistake, though they seem to be the last. Microchip never made the STAMP. That was Parallax. They wrote a BASIC interpreter for the PIC, and sold a PIC that was preprogrammed with the BASIC interpreter. They still do: http://www.parallax.com/tabid/295/Default.aspx -Chuck Harris From wa3frp at aol.com Sat Aug 23 23:21:58 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Sat, 23 Aug 2008 23:21:58 -0400 Subject: [time-nuts] Description - GR 1120-AB Frequency Standard Message-ID: <8CAD3AFB360C2C2-C84-4D35@FWM-M38.sysops.aol.com> Max is correct. The GR 1120-AB contains the following units in a standard relay rack: The GR Standard Frequency Oscillator 1113-A with an output frequency of 5 MHz. This unit is settable to 1 x10 -10 with an output of 1 V RMS. Located in the relay rack above the Standard Frequency Oscillator is the GR Frequency Divider 1114-A (all discrete transistor) with inputs of 5 MHz, 1 MHz and 100 MHz and outputs of 1 MHz (Sine), 100 kHz (Sine + Square), 10kHz (Sine + Square), 1 kHz (Sine) with two output jacks and 100 Hz (Sine) with two output jacks. There were plug-in options that provided additional outputs of 400 Hz and 60 Hz output but unfortunately I don't have either option installed. Installed in the relay rack above the Frequency Divider is the GR Syncronometer Time Comparitor 1103-B. The GR 1103-B uses a 1 kHz motor and 24 hour clock to display the integral of the number of cycles executed by the standard frequency oscillator as a standard time interval. The GR 1103-B contains a set of dry contacts that open one each second for 0.05 seconds. In the mid-1960s, this time standard was compared to a standard time radio station, such as WWV, using the GR 1103-B. While this a beautiful piece of mechanical gear, a HP 117A is much easier to use. The bottom of the relay rack includes the Battery Storage drawer, the GR 1268-A Automatic Battery Charging Unit and the GR 1116-B Emergency Power Supply. These three pieces of equipment are capable of maintaining power to the rack for four hours in the case of commercial power failure. This particular GR 1120-AB, rack number 195, was donated by General Radio to the Moore School of Electrical Engineering - University of Pennsylvania in 1965. The equipment was assigned to the School's Valley Forge Research Center in the late 1960s and remained there serving as the time standard for a number of research projects. By the late 1970s, the GR 1120-AB was stored in an unheated area at Valley Forge and was unused. I was granted approval to remove the Standard after approaching the administration at Penn. Otherwise, it would probably be in a landfill today. My work to completely electrically and mechanically restore this Standard started in May 2004. Once the inner oven thermoswitch is replaced and tested, the Standard will be completely operational. Probably one of the few remaining GR 1120-AB racks in the world. -----Original Message----- From: Max Robinson To: Discussion of precise time and frequency measurement Sent: Sat, 23 Aug 2008 1:19 am Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard There must have been several different versions of this unit. The oscillator I have is 5 MHz. The frequency dividers in the rack I got it out of were discrete transistor construction. Seems to me the clock used a 25L6 although I don't remember how they derived the heater voltage. There was also a phase locked frequency multiplier with outputs at 10 MHz, 100 MHz and 1 GHz. The frequency divider module had outputs down to 1 PPS. After typing that I'm not sure the oscillator frequency is right. Maybe it's 1 MHz. I'm sure it's not 100 kHz. 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: "phil" To: "Discussion of precise time and frequency measurement" Sent: Friday, August 22, 2008 10:15 PM Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > ----- Original Message ----- > From: "Magnus Danielson" > To: "Discussion of precise time and frequency measurement" > > Sent: Friday, August 22, 2008 5:25 PM > Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard > > >> phil wrote: >>> Gentlemen, >>> Original poster is trying to "RESTORE" this entire old General Radio >>> Standard ( a rack of equipment) to it's "original" glory. >>> He simply needs a part, a unique thermoswitch or a way to fix it, not >>> retrofit an atomic engine! This is a museum class instrument, 100kc. >>> >>> May I suggest start a new thread on the better/best merits/design of >>> temperature control. >>> Makes it rather difficult to follow a thread as the subject has changed. >> >> My proposal to use capacitive sensing rather than conductive sensing >> would handle the electrode oxide issue. It is meant as a means to go >> around the sensing issue with parts at hand and only some new electronic >> design of very simple form, not the means to supercalibrate something. >> >> I guess this only shows that time-nuts are time-nuts... >> >> Cheers, >> Magnus > > > Magnus, > Perhaps this will help understand why I made that comment. > > That old "primary" standard was quite a contraption. This things heyday > was > in the order of 1950's and used up into the 60's and some models into > early > 70's. Of course it was all tube equipment. > > My unit model was possibly a 620, it predated what Russ has (1100) but was > quite similar in design. Russ's unit has all the multivibrators in one > housing where mine was each separate. I think his is a 100kc oscillator > and > mine was 50kc. > > As I remember the one I had was in two 7-foot racks, a standard side and > frequency measuring side. My oscillator was 50KC though about 300 dollars > in > the mid 6o's would have bought a 100kc quartz bar to upgrade it > > The unit had each module or circuit in a separate 19" rack space all > averaging 8 inch high The main components, a power supply, oscillator > (about > 20 plus rack inches high by itself), separate multivibrators of 100kc, > 10kc, > 1kc, and 100 cycles. Yes they were called multivibrators though all tube. > It > also had a syncronometer at the top of the rack, better known as a clock. > Apparently the crystal was rich in harmonics and they made use of it in > this > assembly. That clock ran off of the 1 kc output. > > The heart of the oscillator, main part of this contraption used a quartz > bar > about 3/8 of an inch square and about 2 inches long suspended on 4 > springs. > If I recall it was a single oven but it's specs called for about > .01-degree > regulation. > > I don't remember all the fine details, but it had many other components > (all > seperate rack units), a separate 5kc interpolation oscillator, amplifier, > and even an 8-inch speaker to zero beat the standard to another unit, > talking about phase lock! > > So as you can see, these vintage units only use/value is that of an > antique > or conversation piece. A 10811 would blow it away performance wise. > > Now with an understanding of that old antique, that discussion was like > putting an electronic ignition in place of the old Ford Model T spark > coil. > You could, but .. You just search for the part. > > So it's not a "time-nut" issue as such other than appreciating the history > or the evolution of time. I can see from the varied posts this is one heck > of a super talented group. I guess we all get involved in something > interesting and easily get carried away, as in the discussion. Granted you > can do a given task many ways, and bantering ideas around is how things > are > born and perfected. Only problem is, it doesn't locate an "original" > antique > part, what he stated he wanted! > > That old GR stuff does occasionally show up, most free to haul off it's so > massive. A bunch of the old vintage GR standard parts was listed as a lot > on > ebay some months ago. > > Someone asked what happened to my old GR stuff. I disposed of over 100 > tons > of old electronics that had accumulated including this old GR stuff. One > of > my sidelines was the used equipment business and the sales of tube stuff > died. I had some 15,000 feet of "junk" as I call all this stuff. > > By the way, according to Bruce, that design of the old "thermoswitch" > achieved resolutions as fine as .001 degrees. > > It would be hard to build any electronic sensor of any design that is that > reliable and repeatable (.001 degree) with a "one-time" factory > calibration > good for a life exceeding 50 years without using a similar sensor design. > The unit in question with the electrode in mercury design lasted about 50 > years before showing it's age and misbehaving. > > Phil > > > > _______________________________________________ > time-nuts mailing list -- 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 gsteinba52 at aol.com Sat Aug 23 23:48:12 2008 From: gsteinba52 at aol.com (gsteinba52 at aol.com) Date: Sat, 23 Aug 2008 23:48:12 -0400 Subject: [time-nuts] TBolt question Message-ID: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> Hi, Just received my TBolt from the TAPR buy and have a quick(?) question: tvb indicated that the unit builds were from ~2005, and indeed, the photo of the TAPR package on Leapsecond.com shows a TBolt from 2005 revision 'E'. The unit I received is build 2002 revision 'B'. Anyone know of differences in the revisions, and whether the OCXO (which Tom found surprisingly excellent) are the same? Thanks, Jerry From wa3frp at aol.com Sun Aug 24 00:32:06 2008 From: wa3frp at aol.com (wa3frp at aol.com) Date: Sun, 24 Aug 2008 00:32:06 -0400 Subject: [time-nuts] Restoring GR 1120-AB Frequency Standard In-Reply-To: <48B0939F.60808@sbcglobal.net> References: <805296.17410.qm@web96101.mail.aue.yahoo.com> <001601c90463$286aefa0$a101a8c0@officemail><48AF2ECB.7040506@rubidium.dyndns.org> <005f01c904ce$7b9b7710$a101a8c0@officemail> <002901c904df$d7d4b7b0$6401a8c0@BACKROOM> <48B0939F.60808@sbcglobal.net> Message-ID: <8CAD3B97FE54726-B28-11B8@WEBMAIL-DC03.sysops.aol.com> Peter, Thanks for the posting and the link. I believe that the 1115-B was the successor to the GR 1113-A that I am restoring. It combines a number of the features of the 1113-A and 1114-A in the same chassis along with a self-contained 24 emergency power supply. Note that the crystal oven design was completely revamped. No double oven. Lower power requirements. The 1120 was described in the April 1961 issue of GR Experimenter. Best Regards, Russ WA3FRP -----Original Message----- From: Peter Putnam To: Discussion of precise time and frequency measurement Sent: Sat, 23 Aug 2008 6:47 pm Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard I've posted some General Radio notes and specifications on their Model 1115-B oscillator, hoping there might be some relevance to the Model 1120. Product specific information starts on page 8. http://www.ni6e.com/genrad/ Regards, Peter NI6E Max Robinson wrote: > There must have been several different versions of this unit. The > oscillator I have is 5 MHz. The frequency dividers in the rack I got it out > of were discrete transistor construction. Seems to me the clock used a 25L6 > although I don't remember how they derived the heater voltage. There was > also a phase locked frequency multiplier with outputs at 10 MHz, 100 MHz and > 1 GHz. The frequency divider module had outputs down to 1 PPS. > > After typing that I'm not sure the oscillator frequency is right. Maybe > it's 1 MHz. I'm sure it's not 100 kHz. > > Regards. > > Max. K 4 O D S. > > _______________________________________________ time-nuts mailing list -- 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 Sun Aug 24 06:45:44 2008 From: vilgotch at bigpond.net.au (Morris Odell) Date: Sun, 24 Aug 2008 20:45:44 +1000 Subject: [time-nuts] another 5061A question References: Message-ID: <001301c905d6$8f877810$ad00a8c0@Morris1> Hi all, As I wrote the other day, I got the 5061A going again and it hasn't missed a beat. One thing I have noticed though, is that the Osc Oven indication on the meter doesn't change at all as the unit warms up as the manual mentions it should. It remains on 45. The unit itself is a 105-6013 and gets warm and seems to function OK. Is this normal? I know these ovens have a 115V preheater which might be working even if the proportional heater is not. The schematic shows that in the Osc Oven position the meter is connected across the heater in series with a thermal link. Does the absence of any variation mean that the heater or link is open or is the preheater keeping it close enough to temp so that the heater doesn't work too hard? How hard is it to open it up? Unfortunately it's back on the rack and another project is on the bench. It might have to stay that way for a week or three, so there's no hurry to get back into it. Cheers to all, Morris From wje at quackers.net Sun Aug 24 08:42:35 2008 From: wje at quackers.net (wje) Date: Sun, 24 Aug 2008 08:42:35 -0400 Subject: [time-nuts] another 5061A question In-Reply-To: <001301c905d6$8f877810$ad00a8c0@Morris1> References: <001301c905d6$8f877810$ad00a8c0@Morris1> Message-ID: <48B1573B.4070704@quackers.net> I just did an oven rebuild on mine. It can be straightforward or not, depending upon what has failed. However, if your unit locks and stays locked, the oven is most likely at least partially working. The VCO loop capture range is very small and it doesn't take a great deal of temperature variation to lose lock. Check your control voltage reading and monitor it over time. If that's varying a lot, you may have an oven issue. Mine stays within about +/- 5 of the setpoint. The meter is across the series regulator for the heater. Mine starts pegged and drops to 46 over about 30 minutes. If you aren't seeing any variation, I'd suspect a problem in the oven loop control. You can easily take the osc out and run it on the bench. Just apply +18v to '20' and '24', using the case as ground. The power driver for the heater is on the pcb at the end of the can with the connectors. Note - be really careful to not connect power to the '+15' pin. This is not an input. It connects to a 15 v Zener in the oven cavity, which will immediately vaporize. Yes, I learned this the hard way. Popular failure points seem to be the series pass transistor for the heater, the 4.7 ohm emitter resistor, and the fusible links for the proportional heater and the quick-heat heater. But, if you actually do have a problem, I'd be more inclined to suspect the thermistor bridge circuitry, which is on a pcb at the other end of the can. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Morris Odell wrote: > Hi all, > > As I wrote the other day, I got the 5061A going again and it hasn't missed a > beat. > > One thing I have noticed though, is that the Osc Oven indication on the > meter doesn't change at all as the unit warms up as the manual mentions it > should. It remains on 45. The unit itself is a 105-6013 and gets warm and > seems to function OK. Is this normal? I know these ovens have a 115V > preheater which might be working even if the proportional heater is not. > > The schematic shows that in the Osc Oven position the meter is connected > across the heater in series with a thermal link. Does the absence of any > variation mean that the heater or link is open or is the preheater keeping > it close enough to temp so that the heater doesn't work too hard? How hard > is it to open it up? > > Unfortunately it's back on the rack and another project is on the bench. It > might have to stay that way for a week or three, so there's no hurry to get > back into it. > > Cheers to all, > > Morris > > > > > _______________________________________________ > time-nuts mailing list -- 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 Sun Aug 24 09:35:10 2008 From: didier at cox.net (Didier Juges) Date: Sun, 24 Aug 2008 08:35:10 -0500 Subject: [time-nuts] TBolt question In-Reply-To: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> Message-ID: <00af01c905ee$3bfd6f70$0a01a8c0@didierhp> I cannot answer exactly this question, but I was told by the Trimble sales manager that somewhere along the lines (probably around 2000), the Tbolt software was revised with the main goal of removing a lot of the lower level settings and adjustments capabilites because too many customers were messing with what they were not supposed to and rendered their Tbolt useless, creating lots of service calls. Unfortunately, he could not tell me which commands were affected, these changes are not reflected in the Tbolt manual, and I do not know at what revision that change was made. So, in that regard, a pre-2000 unit might be more suitable to tinkerers who know what they are doing :-) such as changing the OCXO or using the Tbolt to control an Rb standard instead of an OCXO. Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of gsteinba52 at aol.com > Sent: Saturday, August 23, 2008 10:48 PM > To: time-nuts at febo.com > Subject: [time-nuts] TBolt question > > Hi, > > Just received my TBolt from the TAPR buy and have a quick(?) question: > tvb indicated that the unit builds were from ~2005, and > indeed, the photo of the TAPR package on Leapsecond.com shows > a TBolt from 2005 revision 'E'. The unit I received is build > 2002 revision 'B'. Anyone know of differences in the > revisions, and whether the OCXO (which Tom found surprisingly > excellent) are the same? > Thanks, > 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. > From ka2cdk at cox.net Sun Aug 24 10:21:53 2008 From: ka2cdk at cox.net (Thomas A. Frank) Date: Sun, 24 Aug 2008 10:21:53 -0400 Subject: [time-nuts] TBolt question In-Reply-To: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> Message-ID: <3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> > tvb indicated that the unit builds were from ~2005, and indeed, the > photo of the TAPR package on Leapsecond.com shows a TBolt from 2005 > revision 'E'. The unit I received is build 2002 revision 'B'. > Anyone know of differences in the revisions, and whether the OCXO > (which Tom found surprisingly excellent) are the same? Just to add a little confusion to the mix, mine is marked 5/1/03 Rev A Later build, earlier revision? Interesting... Tom Frank, KA2CDK From aa8k at comcast.net Sun Aug 24 10:39:35 2008 From: aa8k at comcast.net (Mike Naruta AA8K) Date: Sun, 24 Aug 2008 10:39:35 -0400 Subject: [time-nuts] TBolt question In-Reply-To: <3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> <3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> Message-ID: <48B172A7.6010700@comcast.net> I missed out on the group buy because I didn't hear about it until it was over. I'm looking at the one that fluke is selling on eBay, version 3.00. Has anyone had any problems with these? Mike - AA8K Thomas A. Frank wrote: >> tvb indicated that the unit builds were from ~2005, and indeed, the >> photo of the TAPR package on Leapsecond.com shows a TBolt from 2005 >> revision 'E'. The unit I received is build 2002 revision 'B'. >> Anyone know of differences in the revisions, and whether the OCXO >> (which Tom found surprisingly excellent) are the same? > > > > Just to add a little confusion to the mix, mine is marked 5/1/03 Rev A > From ernieperes at aol.com Sun Aug 24 11:02:13 2008 From: ernieperes at aol.com (ernieperes at aol.com) Date: Sun, 24 Aug 2008 11:02:13 -0400 Subject: [time-nuts] TBolt question In-Reply-To: <48B172A7.6010700@comcast.net> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> <3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> <48B172A7.6010700@comcast.net> Message-ID: <8CAD411863AFE23-C0C-5610@WEBMAIL-DF09.sysops.aol.com> Hi Mike, Maybe this one is interested to you...150285595219 Rgds Ernie HG5ED -----Original Message----- From: Mike Naruta AA8K To: Discussion of precise time and frequency measurement Sent: Sun, 24 Aug 2008 4:39 pm Subject: Re: [time-nuts] TBolt question I missed out on the group buy because I didn't hear about it until it was over. I'm looking at the one that fluke is selling on eBay, version 3.00. Has anyone had any problems with these? Mike - AA8K Thomas A. Frank wrote: >> tvb indicated that the unit builds were from ~2005, and indeed, the >> photo of the TAPR package on Leapsecond.com shows a TBolt from 2005 >> revision 'E'. The unit I received is build 2002 revision 'B'. >> Anyone know of differences in the revisions, and whether the OCXO >> (which Tom found surprisingly excellent) are the same? > > > > Just to add a little confusion to the mix, mine is marked 5/1/03 Rev A > _______________________________________________ time-nuts mailing list -- 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 pvince at theiet.org Sun Aug 24 11:31:20 2008 From: pvince at theiet.org (Peter Vince) Date: Sun, 24 Aug 2008 16:31:20 +0100 Subject: [time-nuts] Olympic time standard? Message-ID: <63343.1219591880@uk2.net> Hi Mitch, Not a direct answer to your question, but Omega have a PDF on their web site that might be of interest: http://www.omegawatches.com/uploads/media/olympic_press_kit_en.pdf Regards, Peter Is there a common time standard that all of the timed Olympic events are referenced to? I know that Omega provides the timing, their logo is on every computer that you see. If there is a common reference, how is it distributed to all of the events? Mitch From smace at intt.net Sun Aug 24 11:59:24 2008 From: smace at intt.net (Scott Mace) Date: Sun, 24 Aug 2008 10:59:24 -0500 Subject: [time-nuts] Olympic time standard? In-Reply-To: <63343.1219591880@uk2.net> References: <63343.1219591880@uk2.net> Message-ID: <48B1855C.6050903@intt.net> I found this link: http://www.goodgearguide.com.au/videoview/257930 In the video they talk about it being a quartz standard that is synced to GPS. Scott Peter Vince wrote: > Hi Mitch, > > Not a direct answer to your question, but Omega have a PDF on their web site > that might be of interest: > > http://www.omegawatches.com/uploads/media/olympic_press_kit_en.pdf > > Regards, > > Peter > > > Is there a common time standard that all of the timed > Olympic events are referenced to? I know that Omega > provides the timing, their logo is on every computer > that you see. If there is a common reference, how is > it distributed to all of the events? > > Mitch > > > _______________________________________________ > time-nuts mailing list -- 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.g0dja at tiscali.co.uk Sun Aug 24 12:21:52 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 24 Aug 2008 17:21:52 +0100 Subject: [time-nuts] TBolt question In-Reply-To: <3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> <3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> Message-ID: <48B18AA0.8030707@tiscali.co.uk> Thomas A. Frank wrote: > Just to add a little confusion to the mix, mine is marked 5/1/03 Rev A I wonder who will prove to have the last maked TB? Mine has 4/26/04 Rev E, which I guess is the American notation for 26th April 2004. Dave From sv1bke at usa.net Sun Aug 24 12:50:41 2008 From: sv1bke at usa.net (EMMANOUIL MANTZARAS) Date: Sun, 24 Aug 2008 19:50:41 +0300 Subject: [time-nuts] FE-5680A C-field trimer ?? Message-ID: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> Hi Is there any one that knows where is the c-field trimer in the FE-5680A board ?? Thanks sv1bke From tvb at LeapSecond.com Sun Aug 24 11:24:55 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Sun, 24 Aug 2008 08:24:55 -0700 Subject: [time-nuts] TBolt question References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> Message-ID: <000101c9060e$c9092ba0$040a0a0a@pc52> > Just received my TBolt from the TAPR buy and have a quick(?) question: > tvb indicated that the unit builds were from ~2005, and indeed, > the photo of the TAPR package on Leapsecond.com shows a TBolt > from 2005 revision 'E'. The unit I received is build 2002 revision 'B'. > Anyone know of differences in the revisions, and whether the > OCXO (which Tom found surprisingly excellent) are the same? > Thanks, > Jerry The group buy contained a random mix of rev A through E and manufacturing dates. I don't know what the differences are among the revisions. But I tested each unit so I at least know all the OCXO are equally good. I'm keeping one specimen here of each of the 5 revisions in case something interesting comes up in the future. /tvb From tvb at LeapSecond.com Sun Aug 24 11:24:45 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Sun, 24 Aug 2008 08:24:45 -0700 Subject: [time-nuts] TBolt question References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com><3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> <48B172A7.6010700@comcast.net> Message-ID: <000001c9060e$c88d44e0$040a0a0a@pc52> > I missed out on the group buy because I didn't hear > about it until it was over. > > I'm looking at the one that fluke is selling on eBay, > version 3.00. Has anyone had any problems with these? > > Mike - AA8K Stay tuned; if all works out TAPR will get another batch by mid-September. /tvb From jgd at johngsbbq.com Sun Aug 24 15:50:33 2008 From: jgd at johngsbbq.com (Neon John) Date: Sun, 24 Aug 2008 15:50:33 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> References: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> Message-ID: <9id3b4tn8qb7uepde9r8imugt4b8up4ep6@4ax.com> On Fri, 22 Aug 2008 22:47:12 -0500, Robert Vassar wrote: >I backup to a USB hard disk. I plug it in, backup, unplug it, de- >cable and park it in a filing cabinet. The disk spends 99.99% of >it's life powered off. It should last a decade or more like this, >but I buy a new disk to replace it every 5 years, regardless if it >needs it or not. Really critical stuff goes on a CD-R, stored flat >in a jewel case, and goes in the safe deposit box. My laptop is may main computer. My "backup" procedure consists of cloning the C: drive using a freebie utility called "xxclone" (http://www.xxclone.com). This one is one of the best cloning programs that I've tried and being free is a double bonus. The target drives are the same brand and size as what is installed in my laptop. The bare target drive is connected via a USB-to-EDIE interface cable that I picked up somewhere on the net for about $20. I use 3 drives in rotation so that I have 3 generations of drive snapshots at any given time. That has saved my cookies more than once when I realized after the last clone that I'd deleted something vital. The three "backup" drives stay in my fireproof safe inside zip-lock bags. The zip-lock bags are vital. I learned the hard way during a house fire that even though the fireproof safe protects the media from heat, it doesn't protect it from the acidic smoke and steam that are drawn into the cool interior. If the drive in my laptop fails, I don't have to do a restore. I simply get the latest clone drive out of the safe and install it in my computer and I'm instantly back up and running with the machine state being that of the last snapshot. I do a weekly clone and a daily differential backup to my linux file server running SAMBA using another freebie utility called SyncBack. A flash drive is another option for those non-networked computer users. http://www.2brightsparks.com/. Even when I've been very active, a week's worth of changes easily fits on a 4 gig flash drive. I still have the occasional nightmare when I think about tape backup. More accurately, the time wasted verifying each tape and even then, having the tape not read about half the time when it was needed. Never again! John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN What do you call a blonde's cranial cavity? Vacuum chamber? From wje at quackers.net Sun Aug 24 15:52:32 2008 From: wje at quackers.net (wje) Date: Sun, 24 Aug 2008 15:52:32 -0400 Subject: [time-nuts] FE-5680A C-field trimer ?? In-Reply-To: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> References: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> Message-ID: <48B1BC00.4020500@quackers.net> There's a small hole on the side of the case. This is the trimmer access, at least on mine. Bill Ezell ---------- They said 'Windows or better' so I used Linux. EMMANOUIL MANTZARAS wrote: > Hi > Is there any one that knows where is the c-field trimer in the FE-5680A board > ?? > Thanks > sv1bke > > > > _______________________________________________ > time-nuts mailing list -- 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 Sun Aug 24 16:23:54 2008 From: cdelect at juno.com (corby d dawson) Date: Sun, 24 Aug 2008 13:23:54 -0700 Subject: [time-nuts] 5061A question Message-ID: <20080824.132354.-82309265.0.cdelect@juno.com> Morris, The preheater would not be able to hold the oven at temp. The internal oven must be working or you would not be able to lock. Put the meter position to osc. oven, note reading, unplug unit for about one minute and then plug back in. The meter reading should peg or at least be noticably higher for a a short while than drop back to the initial reading. If that works the approx. 45 reading is where yours runs. There is a select by test resistor on the mainframe to make this read a specific value but does not really do anything else for you! Corby Dawson ____________________________________________________________ Learn to trade with confidence! Online Stock Trading. Click Now! http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3mKCaQcdhLufhnlHl2nj0ievyXDrgWFbJz5RRpJpU6s4ZqXv/ From rexa at sonic.net Sun Aug 24 17:32:42 2008 From: rexa at sonic.net (Rex) Date: Sun, 24 Aug 2008 14:32:42 -0700 Subject: [time-nuts] FE-5680A C-field trimer ?? In-Reply-To: <48B1BC00.4020500@quackers.net> References: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> <48B1BC00.4020500@quackers.net> Message-ID: <48B1D37A.9070207@sonic.net> Have you adjusted it? I tried tweaking that pot on one I had and I didn't see any effect. wje wrote: > There's a small hole on the side of the case. > This is the trimmer access, at least on mine. > > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > > > EMMANOUIL MANTZARAS wrote: > >> Hi >> Is there any one that knows where is the c-field trimer in the FE-5680A board >> ?? >> Thanks >> sv1bke >> >> >> >> > From wje at quackers.net Sun Aug 24 20:11:41 2008 From: wje at quackers.net (wje) Date: Sun, 24 Aug 2008 20:11:41 -0400 Subject: [time-nuts] FE-5680A C-field trimer ?? In-Reply-To: <48B1D37A.9070207@sonic.net> References: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> <48B1BC00.4020500@quackers.net> <48B1D37A.9070207@sonic.net> Message-ID: <48B1F8BD.5020201@quackers.net> Unless you can measure the frequency to at least a few parts in 10e10, you won't see any change. These devices are far more precise than standard frequency counters. You either need something like an HP 5370 or 5371 to measure the difference, or another equally precise oscillator to compare against using a phase meter or your oscilloscope. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Rex wrote: Have you adjusted it? I tried tweaking that pot on one I had and I didn't see any effect. wje wrote: There's a small hole on the side of the case. This is the trimmer access, at least on mine. Bill Ezell ---------- They said 'Windows or better' so I used Linux. EMMANOUIL MANTZARAS wrote: Hi Is there any one that knows where is the c-field trimer in the FE-5680A board ?? Thanks sv1bke _______________________________________________ time-nuts mailing list -- [1]time-nuts at febo.com To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts at febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From kirbybq at bellsouth.net Sun Aug 24 21:37:10 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Sun, 24 Aug 2008 20:37:10 -0500 Subject: [time-nuts] FE-5680A C-field trimer ?? In-Reply-To: <48B1F8BD.5020201@quackers.net> References: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> <48B1BC00.4020500@quackers.net> <48B1D37A.9070207@sonic.net> <48B1F8BD.5020201@quackers.net> Message-ID: <48B20CC6.404@bellsouth.net> There are several models of the 5680A. A lot use the DDS circuits to set the output frequencies and they do not have C field adjustments. Brian - KD4FM wje wrote: > Unless you can measure the frequency to at least a few parts in 10e10, > you won't see any change. > These devices are far more precise than standard frequency counters. > You either need something like an HP 5370 or 5371 to measure the > difference, or another equally precise oscillator to compare against > using a phase meter or your oscilloscope. > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > Rex wrote: > > Have you adjusted it? I tried tweaking that pot on one I had and I > didn't see any effect. > > wje wrote: > > > There's a small hole on the side of the case. > This is the trimmer access, at least on mine. > > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > > > EMMANOUIL MANTZARAS wrote: > > > > Hi > Is there any one that knows where is the c-field trimer in the FE-5680A board > ?? > Thanks > sv1bke > > > > > > > > _______________________________________________ > time-nuts mailing list -- [1]time-nuts at febo.com > To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > References > > 1. mailto:time-nuts at febo.com > 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > _______________________________________________ > time-nuts mailing list -- 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 Mon Aug 25 01:55:35 2008 From: REMartinson at rcn.com (Bob Martinson) Date: Mon, 25 Aug 2008 01:55:35 -0400 Subject: [time-nuts] Efratom LPRO Rubidium Manual In-Reply-To: <004d01c8dfc2$d62bbfe0$7b01a8c0@pari.edu> Message-ID: This URL found in EBAY item number listing: 280259311638 http://www.2917.com/EBAY-images/LPRO-101/LPRO-101.PDF REM From jim77742 at gmail.com Mon Aug 25 03:40:14 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Mon, 25 Aug 2008 17:40:14 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! Message-ID: Hi Folks, Well I've had the best weekend since I've just acquired a pendulum clock that used to be a telecommunication time standard in the 50s. It is a German made Siemens pendulum master clock that is about 150cm high and has a full-length seconds pendulum which is about a metre long. It is powered by 48V to automatically wind the weight up and will maintain time for about 8 hours without power. The pendulum has an adjustment to raise and lower the 7.5kg weight to calibrate the clock. One full turn of this knob will advance or retard the clock by 40 seconds per day. It is graduated into 100 divisions enabling you to adjust it within 0.4 seconds per day. Half way up the pendulum is a little tray where you can deposit small weights for your final adjustment (and most importantly without stopping the pendulum!) Even though it's a master clock it is also designed to be synchronised to another master clock and so there is an armature on the pendulum that can be steered by a magnetic coil. I have no documentation on this bit, but when I figure it out I naturally shall be driving it from a 1PPS reference. (See photo.) There are numerous contacts that are designed to open/shut at various times including every second, every thirty seconds and minute. The photo shows the mechanism behind the clock face. By connecting the seconds contact up to my 5370B I tuned it quite quickly to be accurate to about a second a day. Which is about 10 microseconds per pendulum swing! I'm impressed a tick tock clock can do that. (Although it pales into insignificance compared to what Harrison accomplished.) It is beautifully constructed and now one of my prized possessions! (I'll put some more photos in another post.) Regards, Jim -------------- next part -------------- A non-text attachment was scrubbed... Name: IMGP4585.jpg Type: image/jpeg Size: 79075 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080825/6ac71083/attachment-0001.jpg From didier at cox.net Mon Aug 25 03:48:56 2008 From: didier at cox.net (Didier Juges) Date: Mon, 25 Aug 2008 02:48:56 -0500 Subject: [time-nuts] Efratom LPRO Rubidium Manual In-Reply-To: References: <004d01c8dfc2$d62bbfe0$7b01a8c0@pari.edu> Message-ID: <001201c90687$077b6a10$0a01a8c0@didierhp> That's the same manual I have on my web site: http://www.ko4bb.com/cgi-bin/manuals.pl Search for LPRO Didier KO4BB > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Bob Martinson > Sent: Monday, August 25, 2008 12:56 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Efratom LPRO Rubidium Manual > > This URL found in EBAY item number listing: 280259311638 > > > http://www.2917.com/EBAY-images/LPRO-101/LPRO-101.PDF > > > > REM > > _______________________________________________ > time-nuts mailing list -- 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 jim77742 at gmail.com Mon Aug 25 04:00:25 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Mon, 25 Aug 2008 18:00:25 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: Here's an an extra photo showing the clock mechanism after the face and hands have been removed. Jim -------------- next part -------------- A non-text attachment was scrubbed... Name: IMGP4578.jpg Type: image/jpeg Size: 91018 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080825/ce03589f/attachment-0001.jpg From jim77742 at gmail.com Mon Aug 25 04:01:05 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Mon, 25 Aug 2008 18:01:05 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: And one more showing the coil that steers the pendulum. -------------- next part -------------- A non-text attachment was scrubbed... Name: IMGP4581.jpg Type: image/jpeg Size: 56701 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080825/43debd60/attachment-0001.jpg From vilgotch at bigpond.net.au Mon Aug 25 04:18:56 2008 From: vilgotch at bigpond.net.au (Morris Odell) Date: Mon, 25 Aug 2008 18:18:56 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! References: Message-ID: <000a01c9068b$3800b100$ad00a8c0@Morris1> You are a lucky man with foresight! One of the many bruises I have accumulated over years of kicking myself relates to passing up on an offer to obtain a couple of those. I do have a rather mundane grandfather clock which would benefit from the 1 pps treatment though. Just need to pursuade the domestic engineering manager...... Morris > Date: Mon, 25 Aug 2008 17:40:14 +1000 > From: "Jim Palfreyman" > Subject: [time-nuts] I now have a clock accurate to 10E-6!!! > To: "Discussion of precise time and frequency measurement" > > Message-ID: > > Content-Type: text/plain; charset="iso-8859-1" > > Hi Folks, > > Well I've had the best weekend since I've just acquired a pendulum clock > that used to be a telecommunication time standard in the 50s. It is a > German > made Siemens pendulum master clock that is about 150cm high and has a > full-length seconds pendulum which is about a metre long. It is powered by > 48V to automatically wind the weight up and will maintain time for about 8 > hours without power. From pfmonet at wanadoo.fr Mon Aug 25 05:18:28 2008 From: pfmonet at wanadoo.fr (=?iso-8859-1?Q?Pierre-Fran=E7ois_=28f5bqp=5Fpfm=29?=) Date: Mon, 25 Aug 2008 11:18:28 +0200 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! References: Message-ID: <015501c90693$8985b450$4501a8c0@r44> Congratulation Jim, you really have a nice pendulum!!! pf (Pierre-Fran?ois) F5BQP ----- Original Message ----- From: "Jim Palfreyman" To: "Discussion of precise time and frequency measurement" Sent: Monday, August 25, 2008 10:01 AM Subject: Re: [time-nuts] I now have a clock accurate to 10E-6!!! And one more showing the coil that steers the pendulum. __________ Information NOD32 3383 (20080824) __________ Ce message a ete verifie par NOD32 Antivirus System. http://www.nod32.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 paul at greenrover.demon.co.uk Mon Aug 25 05:33:11 2008 From: paul at greenrover.demon.co.uk (paul at greenrover.demon.co.uk) Date: Mon, 25 Aug 2008 10:33:11 +0100 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: <48B27C57.7090703@greenrover.demon.co.uk> Jim Palfreyman wrote: > Here's an an extra photo showing the clock mechanism after the face and > hands have been removed. > > Jim Almost identical to the master clock(s) that were used to synchronise the British Railways station clocks in about 1980. A 48v 1pps was distributed by private wire to many stations and platforms. Keeping all of the clocks in synch was a full time job. As a young hard up engineer I recall being quite jealous of the engineer who got paid overtime twice a year to manually do the daylight saving correction :-) It was replaced by a new system with digital displays on the platforms and I kicked myself years later for not keeping one of the old pulse clocks for posterity. Regards Paul -- 73 de Paul GW8IZR IO73TI http://www.gw8izr.com From wje at quackers.net Mon Aug 25 07:07:09 2008 From: wje at quackers.net (wje) Date: Mon, 25 Aug 2008 07:07:09 -0400 Subject: [time-nuts] FE-5680A C-field trimer ?? In-Reply-To: <48B20CC6.404@bellsouth.net> References: <870mHXqxp3708S01.1219596641@cmsweb01.cms.usa.net> <48B1BC00.4020500@quackers.net> <48B1D37A.9070207@sonic.net> <48B1F8BD.5020201@quackers.net> <48B20CC6.404@bellsouth.net> Message-ID: <48B2925D.2040801@quackers.net> Yes, I forgot about those. If I remember correctly, a -20 option has DDS. It's sometimes hard to tell which one you have without opening it up. My 5680A came from an EBay auction where the seller claimed it was programmable. It wasn't. It has the non-DDS 10 Mhz sine output. However, I think that if the pot is installed, you have an adjustable C-field. I'm not positive about this, though. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Brian Kirby wrote: There are several models of the 5680A. A lot use the DDS circuits to set the output frequencies and they do not have C field adjustments. Brian - KD4FM wje wrote: Unless you can measure the frequency to at least a few parts in 10e10, you won't see any change. These devices are far more precise than standard frequency counters. You either need something like an HP 5370 or 5371 to measure the difference, or another equally precise oscillator to compare against using a phase meter or your oscilloscope. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Rex wrote: Have you adjusted it? I tried tweaking that pot on one I had and I didn't see any effect. wje wrote: There's a small hole on the side of the case. This is the trimmer access, at least on mine. Bill Ezell ---------- They said 'Windows or better' so I used Linux. EMMANOUIL MANTZARAS wrote: Hi Is there any one that knows where is the c-field trimer in the FE-5680A board ?? Thanks sv1bke _______________________________________________ time-nuts mailing list -- [[1]1]time-nuts at febo.com To unsubscribe, go to [2][2]https://www.febo.com/cgi-bin/mailman/listinfo/time-n uts and follow the instructions there. References 1. [3]mailto:time-nuts at febo.com 2. [4]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list -- [5]time-nuts at febo.com To unsubscribe, go to [6]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [7]time-nuts at febo.com To unsubscribe, go to [8]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:1]time-nuts at febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 3. mailto:time-nuts at febo.com 4. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 5. mailto:time-nuts at febo.com 6. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 7. mailto:time-nuts at febo.com 8. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From ka2cdk at cox.net Mon Aug 25 07:44:24 2008 From: ka2cdk at cox.net (Thomas A. Frank) Date: Mon, 25 Aug 2008 07:44:24 -0400 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: <6CDCAB6E-C88A-4D2F-86FC-3E23975D2887@cox.net> Jim; Congratulations, that is a really nice looking clock! You may have a real gem there. While the movement doesn't look like anything special, the pendulum looks like a Riefler. Which is something quite special...sort of like having a Thunderbolt inside your bedside alarm clock... Tom Frank On Aug 25, 2008, at 3:40 AM, Jim Palfreyman wrote: > Hi Folks, > > Well I've had the best weekend since I've just acquired a pendulum > clock > that used to be a telecommunication time standard in the 50s. It is > a German > made Siemens pendulum master clock that is about 150cm high and has a > full-length seconds pendulum which is about a metre long. It is > powered by > 48V to automatically wind the weight up and will maintain time for > about 8 > hours without power. > > The pendulum has an adjustment to raise and lower the 7.5kg weight to > calibrate the clock. One full turn of this knob will advance or > retard the > clock by 40 seconds per day. It is graduated into 100 divisions > enabling you > to adjust it within 0.4 seconds per day. Half way up the pendulum is a > little tray where you can deposit small weights for your final > adjustment > (and most importantly without stopping the pendulum!) > > Even though it's a master clock it is also designed to be > synchronised to > another master clock and so there is an armature on the pendulum > that can be > steered by a magnetic coil. I have no documentation on this bit, > but when I > figure it out I naturally shall be driving it from a 1PPS > reference. (See > photo.) > > There are numerous contacts that are designed to open/shut at > various times > including every second, every thirty seconds and minute. The photo > shows the > mechanism behind the clock face. > > By connecting the seconds contact up to my 5370B I tuned it quite > quickly to > be accurate to about a second a day. Which is about 10 microseconds > per > pendulum swing! I'm impressed a tick tock clock can do that. > (Although it > pales into insignificance compared to what Harrison accomplished.) > > It is beautifully constructed and now one of my prized possessions! > > (I'll put some more photos in another post.) > > Regards, > > Jim_______________________________________________ > time-nuts mailing list -- 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 Mon Aug 25 11:00:48 2008 From: jgd at johngsbbq.com (Neon John) Date: Mon, 25 Aug 2008 11:00:48 -0400 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: On Mon, 25 Aug 2008 17:40:14 +1000, "Jim Palfreyman" wrote: >Hi Folks, > >Well I've had the best weekend since I've just acquired a pendulum clock >that used to be a telecommunication time standard in the 50s. Nice. I'd love to have a photo of that with both the clock and the rack of HP goodies both showing. Move to the right a little, maybe use a tripod and turn off the flash to get more uniform lighting and the result would be a wonderful contrast between old and new. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN *fas-cism* (fash'iz'em) n. A system of government that exercises a dictatorship of the extreme right, typically through the merging of state and business leadership, together with belligerent nationalism. -- The American Heritage Dictionary, 1983 From smace at intt.net Mon Aug 25 11:20:52 2008 From: smace at intt.net (Scott Mace) Date: Mon, 25 Aug 2008 10:20:52 -0500 Subject: [time-nuts] hpgps ntp refclock driver and leap second Message-ID: <48B2CDD4.1050803@intt.net> Shouldn't the hpgps ntp driver wait to raise the leap second flag until a month before the leap second and not whenever the satellite happens to first transmit it? See attached patch. diff -u refclock_hpgps.c.orig refclock_hpgps.c --- refclock_hpgps.c.orig 2008-08-25 09:49:59.000000000 -0500 +++ refclock_hpgps.c 2008-08-25 09:56:29.000000000 -0500 @@ -535,7 +535,8 @@ switch (leapchar) { case '+': - pp->leap = LEAP_ADDSECOND; + if ((month == 6) || (month == 12)) + pp->leap = LEAP_ADDSECOND; break; case '0': @@ -543,7 +544,8 @@ break; case '-': - pp->leap = LEAP_DELSECOND; + if ((month == 6) || (month == 12)) + pp->leap = LEAP_DELSECOND; break; default: From GDowd at symmetricom.com Mon Aug 25 11:42:25 2008 From: GDowd at symmetricom.com (Greg Dowd) Date: Mon, 25 Aug 2008 08:42:25 -0700 Subject: [time-nuts] hpgps ntp refclock driver and leap second In-Reply-To: <48B2CDD4.1050803@intt.net> References: <48B2CDD4.1050803@intt.net> Message-ID: In NTPv4, the warning is propagated as soon as it is available. If it were more than 6 months in advance, this could be an issue but that hasn't happened yet. NTP also ignores the alternate (Mar/Sept) leap windows by design. Greg Dowd gdowd at symmetricom dot com (antispam format) Symmetricom, Inc. www.symmetricom.com "Everything should be made as simple as possible, but no simpler" Albert Einstein > -----Original Message----- > From: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] On Behalf Of Scott Mace > Sent: Monday, August 25, 2008 8:21 AM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] hpgps ntp refclock driver and leap second > > Shouldn't the hpgps ntp driver wait to raise the leap second > flag until a month before the leap second and not whenever > the satellite happens > to first transmit it? See attached patch. > > diff -u refclock_hpgps.c.orig refclock_hpgps.c > --- refclock_hpgps.c.orig 2008-08-25 09:49:59.000000000 -0500 > +++ refclock_hpgps.c 2008-08-25 09:56:29.000000000 -0500 > @@ -535,7 +535,8 @@ > switch (leapchar) { > > case '+': > - pp->leap = LEAP_ADDSECOND; > + if ((month == 6) || (month == 12)) > + pp->leap = LEAP_ADDSECOND; > break; > > case '0': > @@ -543,7 +544,8 @@ > break; > > case '-': > - pp->leap = LEAP_DELSECOND; > + if ((month == 6) || (month == 12)) > + pp->leap = LEAP_DELSECOND; > break; > > default: > > _______________________________________________ > time-nuts mailing list -- 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 smace at intt.net Mon Aug 25 12:00:33 2008 From: smace at intt.net (Scott Mace) Date: Mon, 25 Aug 2008 11:00:33 -0500 Subject: [time-nuts] hpgps ntp refclock driver and leap second In-Reply-To: References: <48B2CDD4.1050803@intt.net> Message-ID: <48B2D721.4060000@intt.net> With the oncore VP in the z3801a isn't this a bug/feature of the Bj command to announce it as soon as it is available, while other/newer receivers wait till the month prior? There is even a workaround for this in the oncore refclock driver. Scott Greg Dowd wrote: > In NTPv4, the warning is propagated as soon as it is available. If it > were more than 6 months in advance, this could be an issue but that > hasn't happened yet. NTP also ignores the alternate (Mar/Sept) leap > windows by design. > > > > Greg Dowd > gdowd at symmetricom dot com (antispam format) > Symmetricom, Inc. > www.symmetricom.com > "Everything should be made as simple as possible, but no simpler" Albert > Einstein > > >> -----Original Message----- >> From: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] On Behalf Of Scott Mace >> Sent: Monday, August 25, 2008 8:21 AM >> To: Discussion of precise time and frequency measurement >> Subject: [time-nuts] hpgps ntp refclock driver and leap second >> >> Shouldn't the hpgps ntp driver wait to raise the leap second >> flag until a month before the leap second and not whenever >> the satellite happens >> to first transmit it? See attached patch. >> >> diff -u refclock_hpgps.c.orig refclock_hpgps.c >> --- refclock_hpgps.c.orig 2008-08-25 09:49:59.000000000 -0500 >> +++ refclock_hpgps.c 2008-08-25 09:56:29.000000000 -0500 >> @@ -535,7 +535,8 @@ >> switch (leapchar) { >> >> case '+': >> - pp->leap = LEAP_ADDSECOND; >> + if ((month == 6) || (month == 12)) >> + pp->leap = LEAP_ADDSECOND; >> break; >> >> case '0': >> @@ -543,7 +544,8 @@ >> break; >> >> case '-': >> - pp->leap = LEAP_DELSECOND; >> + if ((month == 6) || (month == 12)) >> + pp->leap = LEAP_DELSECOND; >> break; >> >> default: >> >> _______________________________________________ >> time-nuts mailing list -- 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 belanning at verizon.net Mon Aug 25 17:51:35 2008 From: belanning at verizon.net (Bruce Lanning) Date: Mon, 25 Aug 2008 17:51:35 -0400 Subject: [time-nuts] While we're discussing backups... References: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> <9id3b4tn8qb7uepde9r8imugt4b8up4ep6@4ax.com> Message-ID: <4992307F6C294EF19FAED4CDC0D32998@BRUCE> In regard to the below info, I downloaded xxclone and it does appear to be the type of backup program that I have been looking for, BUT I can not get my C: drive to come up in the source or the target window. I am running XP on a COMPAQ Presario if that helps. Could anyone tell me why I can not see my C: drive. It has my start up info and WINDOWS on it. Bruce ---- Original Message ----- From: "Neon John" To: "Discussion of precise time and frequency measurement" Sent: Sunday, August 24, 2008 3:50 PM Subject: Re: [time-nuts] While we're discussing backups... > On Fri, 22 Aug 2008 22:47:12 -0500, Robert Vassar > wrote: > > >>I backup to a USB hard disk. I plug it in, backup, unplug it, de- >>cable and park it in a filing cabinet. The disk spends 99.99% of >>it's life powered off. It should last a decade or more like this, >>but I buy a new disk to replace it every 5 years, regardless if it >>needs it or not. Really critical stuff goes on a CD-R, stored flat >>in a jewel case, and goes in the safe deposit box. > > My laptop is may main computer. My "backup" procedure consists of cloning > the > C: drive using a freebie utility called "xxclone" > (http://www.xxclone.com). > This one is one of the best cloning programs that I've tried and being > free is > a double bonus. > > The target drives are the same brand and size as what is installed in my > laptop. The bare target drive is connected via a USB-to-EDIE interface > cable > that I picked up somewhere on the net for about $20. I use 3 drives in > rotation so that I have 3 generations of drive snapshots at any given > time. > That has saved my cookies more than once when I realized after the last > clone > that I'd deleted something vital. The three "backup" drives stay in my > fireproof safe inside zip-lock bags. The zip-lock bags are vital. I > learned > the hard way during a house fire that even though the fireproof safe > protects > the media from heat, it doesn't protect it from the acidic smoke and steam > that are drawn into the cool interior. > > If the drive in my laptop fails, I don't have to do a restore. I simply > get > the latest clone drive out of the safe and install it in my computer and > I'm > instantly back up and running with the machine state being that of the > last > snapshot. > > I do a weekly clone and a daily differential backup to my linux file > server > running SAMBA using another freebie utility called SyncBack. A flash drive > is > another option for those non-networked computer users. > http://www.2brightsparks.com/. Even when I've been very active, a week's > worth of changes easily fits on a 4 gig flash drive. > > I still have the occasional nightmare when I think about tape backup. > More > accurately, the time wasted verifying each tape and even then, having the > tape > not read about half the time when it was needed. Never again! > > John > -- > John De Armond > See my website for my current email address > http://www.neon-john.com > http://www.johndearmond.com <-- best little blog on the net! > Tellico Plains, Occupied TN > What do you call a blonde's cranial cavity? Vacuum chamber? > > > _______________________________________________ > time-nuts mailing list -- 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. > Version: 7.5.524 / Virus Database: 270.6.7/1629 - Release Date: 8/23/2008 > 1:16 PM > From holrum at hotmail.com Mon Aug 25 18:25:55 2008 From: holrum at hotmail.com (Mark Sims) Date: Mon, 25 Aug 2008 22:25:55 +0000 Subject: [time-nuts] E-5680A C-field trimer ?? In-Reply-To: References: Message-ID: Actually the 5680A and 5650A units that have the DDS do have a C-field pot. The DDS is only accurate to 0.01 Hz. They set the C-field to minimum, program the DDS constant that gets the closest to the desired freq into the CPU chip (this is what gets reported by the "S" command), then they tweak the C-field to get the unit exactly on freq. The reference freq reported by the "S" command is NOT the reference freq that the unit is shipped adjusted to. ---------------------------------------- >There are several models of the 5680A. A lot use the DDS circuits to >set the output frequencies and they do not have C field adjustments. _________________________________________________________________ Get thousands of games on your PC, your mobile phone, and the web with Windows?. http://clk.atdmt.com/MRT/go/108588800/direct/01/ From holrum at hotmail.com Mon Aug 25 18:30:33 2008 From: holrum at hotmail.com (Mark Sims) Date: Mon, 25 Aug 2008 22:30:33 +0000 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: Any backup that is stored in the same city as the original (some would say within 100 miles of the city) is NOT a backup. It is just a disk waiting for a (real) disaster. No fire proof safe, baggie, etc is a substitute for physical distance. ---------------------------------------- _________________________________________________________________ Get ideas on sharing photos from people like you. Find new ways to share. http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 From chris.kuethe at gmail.com Mon Aug 25 18:53:00 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Mon, 25 Aug 2008 15:53:00 -0700 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: <91981b3e0808251553w6660248ak4dff8b1a0e424ae@mail.gmail.com> On Mon, Aug 25, 2008 at 3:30 PM, Mark Sims wrote: > > Any backup that is stored in the same city as the original (some would say within 100 miles of the city) is NOT a backup. It is just a disk waiting for a (real) disaster. No fire proof safe, baggie, etc is a substitute for physical distance. wrong. or at least not a complete answer. Any backup that is stored in the same {state,country,continent,planet,...} as the original (some would say within {100, 1000, 10000, 1000000, ...} miles of the city) is NOT a backup. It is just a disk waiting for a (real) disaster. No fire proof safe, baggie, etc is a substitute for physical distance. And a copy in a different dimension where different physical laws apply. And a time machine. And a few deities who owe you favors. ... Nightly rsyncs of my home boxen to a network storage device offer enough protection against my most common failure mode: crappy disks and/or harsh environments. I've lost a half-dozen drives in my thinkpad over the years, dumping the contents back from the backup is sufficient. And what if your nightly snapshot is a hundred miles away? It's still gonna take a few hours to get the image back on to production hardware to start serving again. Nearby replication is also critical. Fail over to one of the backup server, and rebuild the primary at your leisure. Or fail over to the alternate data center. A backup is something that reduces your chances of being unable to recover from a set of failures to an acceptably low level. Spend some time thinking "what could possibly go wrong?", and then decide what you're going to do about it. Sometimes "ignore it" is an acceptable answer. Sometimes the right answer is "spend $1B to build multiple data centers with and have state-of-the-art replication, redundancy and failover everywhere." It's a matter of what it'll cost you if something happens vs. what it'll cost to mitigate that. Also, verifying your backups regularly is important... -- GDB has a 'break' feature; why doesn't it have 'fix' too? From jgd at johngsbbq.com Mon Aug 25 20:32:24 2008 From: jgd at johngsbbq.com (Neon John) Date: Mon, 25 Aug 2008 20:32:24 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <4992307F6C294EF19FAED4CDC0D32998@BRUCE> References: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> <9id3b4tn8qb7uepde9r8imugt4b8up4ep6@4ax.com> <4992307F6C294EF19FAED4CDC0D32998@BRUCE> Message-ID: On Mon, 25 Aug 2008 17:51:35 -0400, "Bruce Lanning" wrote: >In regard to the below info, I downloaded xxclone and it does appear to be >the type of backup program that I have been looking for, BUT I can not get >my C: drive to come up in the source or the target window. I am running XP >on a COMPAQ Presario if that helps. Could anyone tell me why I can not see >my C: drive. It has my start up info and WINDOWS on it. No idea other than the brand name. Compaqs have a rep for stuff like that. Are you running XP? All bets are off if Vista is involved. I've installed xxclone on a number of client and friends' computers and never had a problem. It just came up and ran. Did you try pressing the disk management button to the right of the source and target slots? That brings up windows disk drive management package. What does it show? Is your C drive an NTFS volume that is showing healthy? Have you turned off any services, particularly windows shadow volume copy service? Some "optimization" websites recommend turning that service off but doing so disables just about every backup or clone package that runs in multi-user mode. Do you have any virus bloat-ware like Norton running? If so, it might be interfering with disk detection. I have the freebie Avast package on my machine and before that AVG (release 8 turned into bloatware so I had to change) running with no problems but given the amount of problems I've had in the past with Norton and MaCaffee, I'd be looking there. Have you tried since rebooting the machine? Kind of an obvious question but I had to ask. As a last resort, you might drop them a support note and ask if they've had any reported problems with your model computer. Maybe they'll have a patch or a work-around. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN Multitasking: Reading in the bathroom! From jgd at johngsbbq.com Mon Aug 25 20:48:38 2008 From: jgd at johngsbbq.com (Neon John) Date: Mon, 25 Aug 2008 20:48:38 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: <6oj6b4po469bjkj34coo5qr01ede99et7i@4ax.com> On Mon, 25 Aug 2008 22:30:33 +0000, Mark Sims wrote: > >Any backup that is stored in the same city as the original (some would say within 100 miles of the city) is NOT a backup. It is just a disk waiting for a (real) disaster. No fire proof safe, baggie, etc is a substitute for physical distance. That has to be the silliest thing I've ever seen posted to this list. Even by time-nut standards of pointless overkill. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN In theory, there is no difference between theory and practice. In practice, there is. From kirbybq at bellsouth.net Mon Aug 25 21:22:02 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Mon, 25 Aug 2008 20:22:02 -0500 Subject: [time-nuts] E-5680A C-field trimer ?? In-Reply-To: References: Message-ID: <48B35ABA.2010208@bellsouth.net> Mark, which pot is it ? Rex and myself bought units that were not programmable. Both of us have tweaked the pots and have not seen any change in drift. I turned pots 1 turn per day and did phase observations, over the course of a week. They guy that sold these units on ebay claimed they were programmable but could not produce the information. Its been noted he has changed his ebay user name about every 6 months (that might give you an idea about his operation - he also complained about whiny time-nuts postings about his operation). Mark Sims wrote: > Actually the 5680A and 5650A units that have the DDS do have a C-field pot. The DDS is only accurate to 0.01 Hz. They set the C-field to minimum, program the DDS constant that gets the closest to the desired freq into the CPU chip (this is what gets reported by the "S" command), then they tweak the C-field to get the unit exactly on freq. The reference freq reported by the "S" command is NOT the reference freq that the unit is shipped adjusted to. > ---------------------------------------- > > >> There are several models of the 5680A. A lot use the DDS circuits to >> set the output frequencies and they do not have C field adjustments. >> > > > _________________________________________________________________ > Get thousands of games on your PC, your mobile phone, and the web with Windows?. > http://clk.atdmt.com/MRT/go/108588800/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 jim77742 at gmail.com Mon Aug 25 21:41:53 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Tue, 26 Aug 2008 11:41:53 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: <6CDCAB6E-C88A-4D2F-86FC-3E23975D2887@cox.net> References: <6CDCAB6E-C88A-4D2F-86FC-3E23975D2887@cox.net> Message-ID: Yes the pendulum is a 14mm Riefler. I gather that's significant? Jim 2008/8/25 Thomas A. Frank > Jim; > > Congratulations, that is a really nice looking clock! > > You may have a real gem there. While the movement doesn't look like > anything special, the pendulum looks like a Riefler. > > Which is something quite special...sort of like having a Thunderbolt > inside your bedside alarm clock... > > Tom Frank > > > From jim77742 at gmail.com Mon Aug 25 21:47:24 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Tue, 26 Aug 2008 11:47:24 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: I will get that photo for you. (I didn't actually use a flash - that's just the halogen floor light I use to see what I'm doing.) Also, being a keen amateur photographer with some quite decent equipment I'll put some effort in and make it a good one! In that rack actually is a speaking clock (installed in Australia in the 1980s and my other prized possession) that I acquired a few years back along with my recently purchased 5370B timer/counter and 3325B function generator. Jim > Nice. > > I'd love to have a photo of that with both the clock and the rack of HP > goodies both showing. Move to the right a little, maybe use a tripod and > turn > off the flash to get more uniform lighting and the result would be a > wonderful > contrast between old and new. > > From aa8k at comcast.net Mon Aug 25 22:05:18 2008 From: aa8k at comcast.net (Mike Naruta AA8K) Date: Mon, 25 Aug 2008 22:05:18 -0400 Subject: [time-nuts] TBolt question In-Reply-To: <000001c9060e$c88d44e0$040a0a0a@pc52> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com><3C812502-F4ED-4240-978E-B6C94B02D249@cox.net> <48B172A7.6010700@comcast.net> <000001c9060e$c88d44e0$040a0a0a@pc52> Message-ID: <48B364DE.8070408@comcast.net> Ah, excellent. I'm also a TAPR member. Thank you. Tom Van Baak wrote: >> I missed out on the group buy because I didn't hear >> about it until it was over. >> >> I'm looking at the one that fluke is selling on eBay, >> version 3.00. Has anyone had any problems with these? >> >> Mike - AA8K > > Stay tuned; if all works out TAPR will get another batch by > mid-September. > > /tvb > > From kanab2004 at kanab.net Mon Aug 25 22:53:30 2008 From: kanab2004 at kanab.net (GerryG) Date: Mon, 25 Aug 2008 20:53:30 -0600 Subject: [time-nuts] While we're discussing backups... Message-ID: Never been a fan of clone backups, unless it's a primary server and you have identical machines available. As for backups in distant cities or protected storage vaults, I'd sorta think that depends on what you really need... Another issue with clone backups of system drives, is that I've seen more Windows internal-corruption failures then pure drive/computer failures. And if your OS is already starting to die when you made your last backup, it doesn't help very much. I've got a USB bookshelf drive, together with an old workstation with big drives for a duplicate backup. For most apps, I don't try to clone a drive, but backup the install for the apps, together with any keys. Given Window's scattered installation stuff, critical apps are in VmWare sessions, that can easily be backed up and restored to any machine. Any work-in-progress gets backed up every few hours to a memory stick. I feel those two types of backup are really needed, especially having one that's easy and very fast to do. Gerry From holrum at hotmail.com Mon Aug 25 23:34:11 2008 From: holrum at hotmail.com (Mark Sims) Date: Tue, 26 Aug 2008 03:34:11 +0000 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: Pointless overkill? Ask those people in New Orleans what happens when originals and backups are kept in the same city. I know of several (ex) businesses that wisely kept their backups in different buildings there... all were lost. Ask my friends in Jarrell, Texas (or what's left of them after a tornado leveled the city)... one friend kept backups at his and his parent's house... a lifetime's work lost... not to mention a lot of friends and family. All legitimate disaster plans specify that backups (and contingency operating sites) are not to be kept in the same geographic area. Failure to do so in a corporate setting would expose you to major liability claims. Your comment has to be one of the silliest, most shortsighted, that I have ever seen posted anywhere... ---------------------------------------- That has to be the silliest thing I've ever seen posted to this list. Even by time-nut standards of pointless overkill. _________________________________________________________________ Talk to your Yahoo! Friends via Windows Live Messenger. Find out how. http://www.windowslive.com/explore/messenger?ocid=TXT_TAGLM_WL_messenger_yahoo_082008 From jltran at worldnet.att.net Tue Aug 26 00:17:34 2008 From: jltran at worldnet.att.net (J. L. Trantham) Date: Mon, 25 Aug 2008 23:17:34 -0500 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: Message-ID: <65A0CE44EB334B00B847B613A00EA30F@S0028384766> Folks, I, too, had a great weekend. The Thunderbolt arrived, plugged it in, and it promptly found it's self. I can't wait to put it to work. Thanks to all (TAPR, time-nuts, etc.) for their effort on my behalf. My father (now deceased) collected and repaired clocks for 60 years leaving my brother and I some unique pieces. My prize is a 'FASHION' clock made by the Southern Calendar Clock Company, St. Louis, Mo, patented March 18, 1879. It is a two faced clock with two about ten inch diameter faces, one on top and one on the bottom. The top face displays hours, minutes and seconds, all with 'hands'. The bottom face displays the day of the month, 1 through 31, with a hand that points to the periphery and the month and day of the week in two rectangular openings on either side of the center of the dial. The unique feature is that it keeps long months, short months, and every 4 years, gives February 29 days. It is all mechanical, has two 'springs' for power, one for time and the other to strike the hour of the day. It runs for a week on a single 'wind' and keeps reasonable time. Not to 1 in 10E6 though. Its shortcomings are leap seconds and Daylight Savings Time. Fully manual on those I'm afraid. It is completely mechanical with no electric parts. None the less, quite a piece of work for the 1800's. Thanks again to all for all the work that resulted in the Thunderbolt. I am sure I will have questions in the future but none tonight. Joe -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Jim Palfreyman Sent: Monday, August 25, 2008 2:40 AM To: Discussion of precise time and frequency measurement Subject: [time-nuts] I now have a clock accurate to 10E-6!!! Hi Folks, Well I've had the best weekend since I've just acquired a pendulum clock that used to be a telecommunication time standard in the 50s. It is a German made Siemens pendulum master clock that is about 150cm high and has a full-length seconds pendulum which is about a metre long. It is powered by 48V to automatically wind the weight up and will maintain time for about 8 hours without power. The pendulum has an adjustment to raise and lower the 7.5kg weight to calibrate the clock. One full turn of this knob will advance or retard the clock by 40 seconds per day. It is graduated into 100 divisions enabling you to adjust it within 0.4 seconds per day. Half way up the pendulum is a little tray where you can deposit small weights for your final adjustment (and most importantly without stopping the pendulum!) Even though it's a master clock it is also designed to be synchronised to another master clock and so there is an armature on the pendulum that can be steered by a magnetic coil. I have no documentation on this bit, but when I figure it out I naturally shall be driving it from a 1PPS reference. (See photo.) There are numerous contacts that are designed to open/shut at various times including every second, every thirty seconds and minute. The photo shows the mechanism behind the clock face. By connecting the seconds contact up to my 5370B I tuned it quite quickly to be accurate to about a second a day. Which is about 10 microseconds per pendulum swing! I'm impressed a tick tock clock can do that. (Although it pales into insignificance compared to what Harrison accomplished.) It is beautifully constructed and now one of my prized possessions! (I'll put some more photos in another post.) Regards, Jim From jgd at johngsbbq.com Tue Aug 26 13:10:09 2008 From: jgd at johngsbbq.com (Neon John) Date: Tue, 26 Aug 2008 13:10:09 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> On Tue, 26 Aug 2008 03:34:11 +0000, Mark Sims wrote: > >Pointless overkill? Ask those people in New Orleans what happens when originals and backups are kept in the same city. I know of several (ex) businesses that wisely kept their backups in different buildings there... all were lost. > >Ask my friends in Jarrell, Texas (or what's left of them after a tornado leveled the city)... one friend kept backups at his and his parent's house... a lifetime's work lost... not to mention a lot of friends and family. > >All legitimate disaster plans specify that backups (and contingency operating sites) are not to be kept in the same geographic area. Failure to do so in a corporate setting would expose you to major liability claims. It's a big old world out there and if you look hard enough, you can find something to justify most any plan, regardless of how outrageous, if a single occurance is acceptable justification. Of course, by that standard we all should walk around wearing Kevlar helmets. After all, there has been a single instance of someone being hit by a meteorite in recorded history. If I'd lived and operated a data center in NO even before Katrina, I'd have considered flooding to be a high percentage risk and done something appropriate about it. If I lived in the high desert, I'd not worry too much about flooding. The silliness in your "advice" is that you offered up one of the most extreme "solutions" as generic advice and said that anything less was no backup at all or something to that effect even though you don't know my or any other list member's circumstances. Let's see how your advice and its associate expense fits my situation since I'm the one you replied to. I'm retired so total loss of my data would have no financial impact. A huge sentimental and legacy impact, in terms of both my writings, designs and digital photos. Interestingly enough, all those types of data are backed up multiple ways including on a set of DVDs resting in a friend's safe who lives a few miles away. My past design work is completely static, my photos mostly static and my writings a little less static so updates to that collection need be done only a couple of times a year. They'd only be needed if my cabin and its contents suddenly and completely disappeared somehow. I live in a cabin on gentle sloping ground about 200 feet above the Tellico river. Short of The Great Flood 2.0, water on the ground cannot reach my place. Period. That takes NO-style flooding off the table. The basement of my cabin sits on bedrock. The combination of the gradual slope and the mere skim of topsoil takes land slides off the table. In my basement there is one of the largest gun safes made, one that I can stand up in. It is set through the concrete block wall, back into the soil bank behind my cabin so that the door is flush with the wall. In other words, like a vault. The safe itself weighs about 2 tons. The bottom few inches are filled with another ton of concrete and the foot of the safe is embedded in about 3 yards of steel-reinforced concrete, some of the steel welded to the safe's body. The lockworks are US government crypto-certified. I paid a bunch extra for that quality of lockwork. The combination lock is a Sergent and Green crypto-grade unit and the key lock is a Medico high security one. Both locks must be manipulated to open the safe. Inside the safe is another smaller "valuables" safe, also secured with a S&G crypto-grade combo lock. It was intended for jewelry but I use it for backup media storage. Even sitting in the open it has the highest UL fire rating available. Set back in the dirt bank, it is impervious to fire. The safe is both alarmed and booby-trapped. (certain immaterial-to-this-discussion have been changed for obvious reasons.) I installed this safe years ago when I traveled a lot to protect my gun collection. It makes a damned fine data safe. So let's evaluate the risks Risk Covered? Fire check Earthquake check general flood NA local flood check* explosion check land slide NA B&E check** Tornado check Riot check Nuclear attack check*** Nosey neighbors check * broken water pipe, etc. The basement is drained by gravity plus my alarm system has a leak detection facility that kills power to my well pump. ** adding to my protection against breaking and entering are all my heavily armed and dangerous neighbors. We put teeth in the term "Neighborhood Watch". *** of any nearby strategic target such as Oak Ridge. Can't imagine anyone nuking Tellico Plains :-) Even if they did, I'm still 25 miles and a mountain range away. My lights-out server sits inside the safe with the power and ethernet cables brought out through suitable secure penetrations. I put the server in the safe after the experience of a previous fire. My backups were good but the hassle, time and cost involved in setting up a new server made using available space in the safe for this one a no-brainer. Also sitting in the safe is another laptop just like this one. I stay on the trailing edge of technology so buying a second one cost me almost nothing. This totally eliminates the risk of even an hour of down-time if I break this laptop or it just quits. I swap them occasionally to equalize the wear and tear and to keep the capacitors in the power supply well-formed. There is a small CO2 cylinder in the back of the safe equipped with a spring loaded, solenoid tripped valve. The valve came directly out of an Ansul automatic fire protection system. If triggered by an external thermal rate-of-rise Fenwal switch, it provides a steady flow of inerting gas, good for a couple of hours. This setup is a lessons-learned from my house fire when steam and acidic smoke got past the "air tight" gun safe seal and damaged thousands of dollars worth of guns, even before the fire was completely out. I had the safe open even while the firemen were watering hot spots and my guns were already corroding. Insurance paid OK but some of the guns were literally irreplaceable so I still suffered great loss. Ansul systems can't be reused so the valve setup is a throw-away item at most any used restaurant supply company. The CO2 bottle is an off-the-shelf 20 lb soft drink dispenser cylinder. So. Given my setup, tell me what risk I'm exposed to that would make shipping backup media a hundred miles away and paying someone to store them make economic sense? I think that I have a very well thought-out and complete data security system but I'm always open to second opinions. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN I don't speak Stupid so do speak slowly. From cdelect at juno.com Tue Aug 26 13:22:32 2008 From: cdelect at juno.com (corby d dawson) Date: Tue, 26 Aug 2008 10:22:32 -0700 Subject: [time-nuts] 10811A versus 10811-60111 Message-ID: <20080826.102233.-355005.2.cdelect@juno.com> Hi, I have had the occasion recently to measure the aging and short term stability of a bunch of oscillators. Measurements were against an EFOS-2 Hydrogen Maser. I thought that the results between 10811A (-60109 variant) and the 10811-60111 might be of interest to some. All oscillators had aging below 5X10-10/day. As you can see the short term stability of the -60111 compares favorably with the 10811A. I'll be making some measurements on the -60158 variants and some motorola units soon. Cheers! Corby Dawson QUARTZ 1 SEC. 10 SEC. 100 SEC. 1K SEC. (ALL HAD AGING BELOW 5X10-5/DAY) ------------------------------------------------ 10811-60109 6.11-12 2.52-12 8.78-12 10811-60109 1.65-12 1.91-12 9.79-12 10811-60109 1.65-12 1.99-12 1.11-12 10811-60109 5.47-12 1.16-12 2.38-12 105 STYLE #T 7.60-13 2.01-12 3.94-12 10811-60111 1.27-12 2.65-12 1.93-12 105 STYLE #2 1.14-12 1.57-12 2.26-12 105 STYLE #3 1.31-12 1.58-12 2.68-12 10811-60111 3.04-12 5.54-12 1.47-12 105 STYLE #4 1.38-12 3.49-12 4.84-12 10811-60109 2.05-12 2.89-12 3.24-12 10811-60111 1.36-12 1.17-12 1.75-12 105 STYLE #5 1.14-12 2.09-12 2.51-12 FTS 1200 #1 7.14-13 1.48-12 1.92-12 10543A 2.86-11 1.05-11 1.63-11 FTS 1200 #2 2.99-13 4.30-13 7.69-13 8.65-13 10544A 4.08-12 2.95-12 7.79-12 10811-60111 1.24-12 2.10-12 2.09-12 10811-60111 1.48-12 1.59-12 1.54-12 10544A 1.89-12 2.99-12 5.01-12 105 style #6 2.88-12 2.88-12 7.37-12 105 style #7 9.69-13 2.30-12 3.49-12 10544-60511 8.20-13 2.11-12 2.51-12 Piezo clone 2.57-12 2.23-12 2.17-12 5060A osconly 4.04-12 5.94-12 8.42-12 1.30-11 10811-60111 2.59-12 3.87-12 5.77-12 -60109spec 2.50-12 5.00-12 1.00-11 -60111spec <1.00-12 * * 10811Aspec 5.00-12 5.00-12 1.00-11 *not specified ____________________________________________________________ Click to find information on your credit score and your credit report. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m2PczsRdNFKt2GBl1YDtgaQ4QFPJm37HTYhIBtnzDllyvQl/ From fortime at bellsouth.net Tue Aug 26 14:04:07 2008 From: fortime at bellsouth.net (phil) Date: Tue, 26 Aug 2008 14:04:07 -0400 Subject: [time-nuts] While we're discussing backups... References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> Message-ID: <000601c907a6$22b6ca20$a101a8c0@officemail> ----- Original Message ----- From: "Neon John" To: "Discussion of precise time and frequency measurement" Sent: Tuesday, August 26, 2008 1:10 PM Subject: Re: [time-nuts] While we're discussing backups... > On Tue, 26 Aug 2008 03:34:11 +0000, Mark Sims wrote: > >> >>Pointless overkill? Ask those people in New Orleans what happens when >>originals and backups are kept in the same city. I know of several (ex) >>businesses that wisely kept their backups in different buildings there... >>all were lost. >> >>Ask my friends in Jarrell, Texas (or what's left of them after a tornado >>leveled the city)... one friend kept backups at his and his parent's >>house... a lifetime's work lost... not to mention a lot of friends and >>family. >> >>All legitimate disaster plans specify that backups (and contingency >>operating sites) are not to be kept in the same geographic area. Failure >>to do so in a corporate setting would expose you to major liability >>claims. > > It's a big old world out there and if you look hard enough, you can find > something to justify most any plan, regardless of how outrageous, if a > single > occurance is acceptable justification. Of course, by that standard we all > should walk around wearing Kevlar helmets. After all, there has been a > single > instance of someone being hit by a meteorite in recorded history. > > If I'd lived and operated a data center in NO even before Katrina, I'd > have > considered flooding to be a high percentage risk and done something > appropriate about it. If I lived in the high desert, I'd not worry too > much > about flooding. > > The silliness in your "advice" is that you offered up one of the most > extreme > "solutions" as generic advice and said that anything less was no backup at > all > or something to that effect even though you don't know my or any other > list > member's circumstances. Let's see how your advice and its associate > expense > fits my situation since I'm the one you replied to. > > I'm retired so total loss of my data would have no financial impact. A > huge > sentimental and legacy impact, in terms of both my writings, designs and > digital photos. Interestingly enough, all those types of data are backed > up > multiple ways including on a set of DVDs resting in a friend's safe who > lives > a few miles away. My past design work is completely static, my photos > mostly > static and my writings a little less static so updates to that collection > need > be done only a couple of times a year. They'd only be needed if my cabin > and > its contents suddenly and completely disappeared somehow. > > I live in a cabin on gentle sloping ground about 200 feet above the > Tellico > river. Short of The Great Flood 2.0, water on the ground cannot reach my > place. Period. That takes NO-style flooding off the table. The basement > of > my cabin sits on bedrock. The combination of the gradual slope and the > mere > skim of topsoil takes land slides off the table. > > In my basement there is one of the largest gun safes made, one that I can > stand up in. It is set through the concrete block wall, back into the > soil > bank behind my cabin so that the door is flush with the wall. In other > words, > like a vault. The safe itself weighs about 2 tons. The bottom few inches > are > filled with another ton of concrete and the foot of the safe is embedded > in > about 3 yards of steel-reinforced concrete, some of the steel welded to > the > safe's body. > > The lockworks are US government crypto-certified. I paid a bunch extra > for > that quality of lockwork. The combination lock is a Sergent and Green > crypto-grade unit and the key lock is a Medico high security one. Both > locks > must be manipulated to open the safe. Inside the safe is another smaller > "valuables" safe, also secured with a S&G crypto-grade combo lock. It was > intended for jewelry but I use it for backup media storage. > > Even sitting in the open it has the highest UL fire rating available. Set > back in the dirt bank, it is impervious to fire. The safe is both alarmed > and > booby-trapped. > > (certain immaterial-to-this-discussion have been changed for obvious > reasons.) > > I installed this safe years ago when I traveled a lot to protect my gun > collection. It makes a damned fine data safe. So let's evaluate the > risks > > Risk Covered? > Fire check > Earthquake check > general flood NA > local flood check* > explosion check > land slide NA > B&E check** > Tornado check > Riot check > Nuclear attack check*** > Nosey neighbors check > > * broken water pipe, etc. The basement is drained by gravity plus my > alarm > system has a leak detection facility that kills power to my well pump. > ** adding to my protection against breaking and entering are all my > heavily > armed and dangerous neighbors. We put teeth in the term "Neighborhood > Watch". > *** of any nearby strategic target such as Oak Ridge. Can't imagine > anyone > nuking Tellico Plains :-) Even if they did, I'm still 25 miles and a > mountain > range away. > > My lights-out server sits inside the safe with the power and ethernet > cables > brought out through suitable secure penetrations. I put the server in the > safe after the experience of a previous fire. My backups were good but > the > hassle, time and cost involved in setting up a new server made using > available > space in the safe for this one a no-brainer. > > Also sitting in the safe is another laptop just like this one. I stay on > the > trailing edge of technology so buying a second one cost me almost nothing. > This totally eliminates the risk of even an hour of down-time if I break > this > laptop or it just quits. I swap them occasionally to equalize the wear > and > tear and to keep the capacitors in the power supply well-formed. > > There is a small CO2 cylinder in the back of the safe equipped with a > spring > loaded, solenoid tripped valve. The valve came directly out of an Ansul > automatic fire protection system. If triggered by an external thermal > rate-of-rise Fenwal switch, it provides a steady flow of inerting gas, > good > for a couple of hours. > > This setup is a lessons-learned from my house fire when steam and acidic > smoke > got past the "air tight" gun safe seal and damaged thousands of dollars > worth > of guns, even before the fire was completely out. I had the safe open > even > while the firemen were watering hot spots and my guns were already > corroding. > Insurance paid OK but some of the guns were literally irreplaceable so I > still > suffered great loss. > > Ansul systems can't be reused so the valve setup is a throw-away item at > most > any used restaurant supply company. The CO2 bottle is an off-the-shelf 20 > lb > soft drink dispenser cylinder. > > So. Given my setup, tell me what risk I'm exposed to that would make > shipping > backup media a hundred miles away and paying someone to store them make > economic sense? I think that I have a very well thought-out and complete > data > security system but I'm always open to second opinions. > > John > -- > John De Armond "tell me what risk I'm exposed to" An angry wife ! From chris.kuethe at gmail.com Tue Aug 26 14:17:06 2008 From: chris.kuethe at gmail.com (Chris Kuethe) Date: Tue, 26 Aug 2008 11:17:06 -0700 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> Message-ID: <91981b3e0808261117sba917e6mc19ebbbe35364d87@mail.gmail.com> On Tue, Aug 26, 2008 at 10:10 AM, Neon John wrote: > The silliness in your "advice" is that you offered up one of the most extreme > "solutions" as generic advice and said that anything less was no backup at all > or something to that effect even though you don't know my or any other list > member's circumstances. Let's see how your advice and its associate expense > fits my situation since I'm the one you replied to. Heh. "Let the punishment fit the crime" ... and let the backup strategy fit the risk model. > I'm retired so total loss of my data would have no financial impact. A huge > sentimental and legacy impact, in terms of both my writings, designs and > digital photos. Interestingly enough, all those types of data are backed up > multiple ways including on a set of DVDs resting in a friend's safe who lives > a few miles away. My past design work is completely static, my photos mostly > static and my writings a little less static so updates to that collection need > be done only a couple of times a year. They'd only be needed if my cabin and > its contents suddenly and completely disappeared somehow. Might wanna keep an eye on the DVD's. I hear the dyes aren't quite as stable and long-lived as the manufacturers claim. I've heard rumors of discs being stored undisturbed in safety-deposit boxes for 5yrs starting to break down. Some people I know with a rather small set of backup DVDs read the existing discs and burn a new set every 6-12mo. This serves the purposes of verifying that you can restore from your backup and that your media is fresh. > The lockworks are US government crypto-certified. I paid a bunch extra for > that quality of lockwork. The combination lock is a Sergent and Green > crypto-grade unit and the key lock is a Medico high security one. Both locks > must be manipulated to open the safe. Inside the safe is another smaller > "valuables" safe, also secured with a S&G crypto-grade combo lock. It was > intended for jewelry but I use it for backup media storage. Heard about how "high security" locks may not be as secure as the manufacturers claim? hackaday.com and toool.nl... the lesson from that is to keep reviewing your backup strategy. The chances that someone will have the means, motive and opportunity to come after your safe is probably pretty low. Low enough that you sleep well at night. So yeah, I think we're very much in agreement: think about what you have to lose balanced against how much it'll cost to protect against. And don't rest on your laurels. :) CK -- GDB has a 'break' feature; why doesn't it have 'fix' too? From tom.k3io at gmail.com Tue Aug 26 14:37:40 2008 From: tom.k3io at gmail.com (Tom Clark, K3IO) Date: Tue, 26 Aug 2008 14:37:40 -0400 Subject: [time-nuts] Distribution Amplifier Message-ID: <48B44D74.5020705@verizon.net> Does anyone know anything about this series of 5/10 MHz distribution buffers? Any experience on differences between cheap (#10278) vs expensive (#10273) versions? http://www.timetech.de/index.php?page=products_devices&pgraph=4 Thanks -- Tom Clark From rvassar at rob-vassar.com Tue Aug 26 15:34:29 2008 From: rvassar at rob-vassar.com (Robert Vassar) Date: Tue, 26 Aug 2008 14:34:29 -0500 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> References: <3A4AAEA6-260C-4855-BFB1-909EF0B3EE05@rob-vassar.com> Message-ID: <13F86FE1-F503-4AAF-8461-3C00F6D72FCD@rob-vassar.com> There have certainly been some amusing replies. My only point was that if it you are storing stuff on "spinning rust", you can't call it a backup if it's still spinning. Power it off and de-cable it. How much further you go after that to protect it depends on your risk requirements. I did like the zip-loc bag idea. I live in lightning and tornado country. Less than an hour's drive from Jarrell. :-( From holrum at hotmail.com Tue Aug 26 16:12:20 2008 From: holrum at hotmail.com (Mark Sims) Date: Tue, 26 Aug 2008 20:12:20 +0000 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: A lot of people store their backups in gun safes and fire safes and beleieve they are, well.. safe. Unfortunately this is not at all true. Fire ratings on safes are usually referenced to how long before the paper inside ignites... call it 451 F. Hard drives these days have their bit densities so high that the magnetic domains are on the edge of instability. Brownian motion and thermal noise can flip the domains. That, coupled with ever decreasing Curie points, means that hard drives can lose their data well before the temperature in the safe reaches that of a cool sauna. The more modern the drive, the bigger the problem. Some drives these days are speced at storage temps of less than 50C... well below what even a hot car will produce (I suspect that is the root of a lot of laptop hard drive "failures"). A few more potential backup disasters that I am familiar with... Don't store drives and ammo and powder in the same safe... the fire did not get the safe contents hot enough to ignite the ammo/powder but, apparently, expanding gasses caused cause some of the ammo pop apart, flying slug hit another shell, can of reloading powder went off. Doors to safe came off... Backups and lower levels do not mix... one case was a broken water main in the street filled a basement (and two levels of underground parking with water)... guess where the data center was? Another was a fire safe in a house basement. Water heater set house on fire, pipes burst, basement filled with water. Safe rusted shut before the basement could be pumped out. Personally, I keep newest backup in the guest house (OK against most pipes/small fires/burglary), next one in an office around 15 miles away (OK against tornados, etc), next one is 360 miles away (OK against hurricanes/nukes/small chunks of space rock). If it's worth protecting... do it right. _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 From bruce.griffiths at xtra.co.nz Tue Aug 26 18:13:44 2008 From: bruce.griffiths at xtra.co.nz (Bruce Griffiths) Date: Wed, 27 Aug 2008 10:13:44 +1200 Subject: [time-nuts] Distribution Amplifier In-Reply-To: <48B44D74.5020705@verizon.net> References: <48B44D74.5020705@verizon.net> Message-ID: <48B48018.40000@xtra.co.nz> Tom Clark, K3IO wrote: > Does anyone know anything about this series of 5/10 MHz distribution > buffers? Any experience on differences between cheap (#10278) vs > expensive (#10273) versions? > http://www.timetech.de/index.php?page=products_devices&pgraph=4 > > > Thanks -- Tom Clark > > Tom The only significant spec difference is in the reverse isolation (a few dB) and channel to channel isolation (20dB). Perhaps the cheaper version forgoes some internal shielding. The phase noise floor spec is somewhat higher than the state of the art as well as being higher than that of some OCXOs. Bruce From ch at murgatroid.com Tue Aug 26 19:25:56 2008 From: ch at murgatroid.com (christopher hoover) Date: Tue, 26 Aug 2008 16:25:56 -0700 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: Message-ID: <000001c907d3$1725b1d0$45711570$@com> Robert Vassar said: > There have certainly been some amusing replies. My only point was > that if it you are storing stuff on "spinning rust", you can't call > it a backup if it's still spinning. Power it off and de-cable it. > How much further you go after that to protect it depends on your risk > requirements. I did like the zip-loc bag idea. I've been trying to stay out of this, but I have some expertise digital asset preservation, as it has been a recent research area of mine. (Someone referred LOCKSS -- that's good work and a nice place to start; one of its creators is a colleague of mine.) A couple points are worth making: Diversity of all kinds is good. This would include geography, operating system, media, administrative control, 'players' (i.e. someway to interpret the bits) et al. Extra copies are good (and, yes, you can use coding to avoid 100% overhead for every copy), but you rapidly lose the benefit of the extra copies if you do not actively repair them quickly (enough) after they fail. And here's the rub: a significant fraction of storage failures are latent -- they go undetected until you attempt to retrieve and 'perform' the asset. So to make sure your copies are good, you must audit them regularly. Given trust between administrative domains, this can be as simple as comparing cryptographic hashes of the bits. (There are also schemes that work without assuming trust.) I don't have the ref handy at the moment, but we have a model and math that quantifies the issue around latent errors. But don't audit too often, if the auditing mechanism causes wear. How often is often enough is left an exercise for the reader. These are of course general principles. You still need to look at your threat model and the value of your data and make reasonable engineering choices. -ch From mccorkle at ptialaska.net Tue Aug 26 19:53:52 2008 From: mccorkle at ptialaska.net (Richard H McCorkle) Date: Tue, 26 Aug 2008 15:53:52 -0800 (AKDT) Subject: [time-nuts] 10811A versus 10811-60111 In-Reply-To: <20080826.102233.-355005.2.cdelect@juno.com> References: <20080826.102233.-355005.2.cdelect@juno.com> Message-ID: <16597.206.174.39.163.1219794832.squirrel@mymail.acsalaska.net> Hi Corby, This is a nice collection of data and look forward to seeing how the Motorola and -60158 variants compare. The specs on the -60111 show < 1e-11 @ 1 sec although the results you obtained show they are typically much better than this. Thanks for the data, Richard > Hi, > > I have had the occasion recently to measure the aging and short term > stability of a bunch of oscillators. > > Measurements were against an EFOS-2 Hydrogen Maser. > > I thought that the results between 10811A (-60109 variant) and the > 10811-60111 might be of interest to some. > > All oscillators had aging below 5X10-10/day. > > As you can see the short term stability of the -60111 compares favorably > with the 10811A. > > I'll be making some measurements on the -60158 variants and some motorola > units soon. > > Cheers! > Corby Dawson > > > QUARTZ 1 SEC. 10 SEC. 100 SEC. 1K SEC. (ALL HAD AGING BELOW > 5X10-5/DAY) > ------------------------------------------------ > 10811-60109 6.11-12 2.52-12 8.78-12 > 10811-60109 1.65-12 1.91-12 9.79-12 > 10811-60109 1.65-12 1.99-12 1.11-12 > 10811-60109 5.47-12 1.16-12 2.38-12 > 105 STYLE #T 7.60-13 2.01-12 3.94-12 > 10811-60111 1.27-12 2.65-12 1.93-12 > 105 STYLE #2 1.14-12 1.57-12 2.26-12 > 105 STYLE #3 1.31-12 1.58-12 2.68-12 > 10811-60111 3.04-12 5.54-12 1.47-12 > 105 STYLE #4 1.38-12 3.49-12 4.84-12 > 10811-60109 2.05-12 2.89-12 3.24-12 > 10811-60111 1.36-12 1.17-12 1.75-12 > 105 STYLE #5 1.14-12 2.09-12 2.51-12 > FTS 1200 #1 7.14-13 1.48-12 1.92-12 > 10543A 2.86-11 1.05-11 1.63-11 > FTS 1200 #2 2.99-13 4.30-13 7.69-13 8.65-13 > 10544A 4.08-12 2.95-12 7.79-12 > 10811-60111 1.24-12 2.10-12 2.09-12 > 10811-60111 1.48-12 1.59-12 1.54-12 > 10544A 1.89-12 2.99-12 5.01-12 > 105 style #6 2.88-12 2.88-12 7.37-12 > 105 style #7 9.69-13 2.30-12 3.49-12 > 10544-60511 8.20-13 2.11-12 2.51-12 > Piezo clone 2.57-12 2.23-12 2.17-12 > 5060A osconly 4.04-12 5.94-12 8.42-12 1.30-11 > 10811-60111 2.59-12 3.87-12 5.77-12 > > -60109spec 2.50-12 5.00-12 1.00-11 > -60111spec <1.00-12 * * > 10811Aspec 5.00-12 5.00-12 1.00-11 > *not specified > ____________________________________________________________ > Click to find information on your credit score and your credit report. > http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m2PczsRdNFKt2GBl1YDtgaQ4QFPJm37HTYhIBtnzDllyvQl/ > > _______________________________________________ > time-nuts mailing list -- 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 Tue Aug 26 19:55:44 2008 From: jgd at johngsbbq.com (Neon John) Date: Tue, 26 Aug 2008 19:55:44 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <000601c907a6$22b6ca20$a101a8c0@officemail> References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> <000601c907a6$22b6ca20$a101a8c0@officemail> Message-ID: On Tue, 26 Aug 2008 14:04:07 -0400, "phil" wrote: >"tell me what risk I'm exposed to" >An angry wife ! She and my (former) best friend ran away about 5 years ago. Thankfully. :-) John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN Ignorance more frequently begets confidence than does knowledge. -Darwin From brooke at pacific.net Tue Aug 26 20:03:06 2008 From: brooke at pacific.net (brooke at pacific.net) Date: Tue, 26 Aug 2008 17:03:06 -0700 (PDT) Subject: [time-nuts] While we're discussing backups... In-Reply-To: <000001c907d3$1725b1d0$45711570$@com> References: <000001c907d3$1725b1d0$45711570$@com> Message-ID: <3599.QwUHAQhUTUc=.1219795386.squirrel@webmail.securepacific.net> Hi: I haven't been reading my email for a few months while I'm out of the country but happened on this one while doing something else. This is a subject where I have years of practical experience. Key Point: In my experience the only backup that you can trust is one where you use it immediately! For example a friend was using a RAID system for a number of years then one day got a message saying there was a disk problem. He spent $4000 to have a recovery service reclaim the hard drive. To accomplish the backup what's needed is to make a clone of the hard drive, remove the current hard drive as the backup and continue to work from the new hard drive. A side benefit of this is that the new hard drive will have a larger capacity and cost less than the prior drive. This was easy to do on WIN98 but starting with WIN XP SP2 you can NOT have two bootable operating systems on the disk drives so cloning (Norton Ghost) requires a boot into DOS. This is probably a Microsoft anti copy "feature". Brooke Clarke > Robert Vassar said: >> There have certainly been some amusing replies. My only point was >> that if it you are storing stuff on "spinning rust", you can't call >> it a backup if it's still spinning. Power it off and de-cable it. >> How much further you go after that to protect it depends on your risk >> requirements. I did like the zip-loc bag idea. > > I've been trying to stay out of this, but I have some expertise digital > asset preservation, as it has been a recent research area of mine. > > (Someone referred LOCKSS -- that's good work and a nice place to start; > one > of its creators is a colleague of mine.) > > A couple points are worth making: > > Diversity of all kinds is good. This would include geography, operating > system, media, administrative control, 'players' (i.e. someway to > interpret > the bits) et al. > > Extra copies are good (and, yes, you can use coding to avoid 100% overhead > for every copy), but you rapidly lose the benefit of the extra copies if > you > do not actively repair them quickly (enough) after they fail. > > And here's the rub: a significant fraction of storage failures are latent > -- > they go undetected until you attempt to retrieve and 'perform' the asset. > > So to make sure your copies are good, you must audit them regularly. > Given > trust between administrative domains, this can be as simple as comparing > cryptographic hashes of the bits. (There are also schemes that work > without assuming trust.) > > I don't have the ref handy at the moment, but we have a model and math > that > quantifies the issue around latent errors. > > But don't audit too often, if the auditing mechanism causes wear. How > often is often enough is left an exercise for the reader. > > These are of course general principles. You still need to look at your > threat model and the value of your data and make reasonable engineering > choices. > > -ch > > > > > _______________________________________________ > time-nuts mailing list -- 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 Tue Aug 26 20:47:26 2008 From: jgd at johngsbbq.com (Neon John) Date: Tue, 26 Aug 2008 20:47:26 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <91981b3e0808261117sba917e6mc19ebbbe35364d87@mail.gmail.com> References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> <91981b3e0808261117sba917e6mc19ebbbe35364d87@mail.gmail.com> Message-ID: On Tue, 26 Aug 2008 11:17:06 -0700, "Chris Kuethe" wrote: >Might wanna keep an eye on the DVD's. I hear the dyes aren't quite as >stable and long-lived as the manufacturers claim. I've heard rumors of >discs being stored undisturbed in safety-deposit boxes for 5yrs >starting to break down. Some people I know with a rather small set of >backup DVDs read the existing discs and burn a new set every 6-12mo. >This serves the purposes of verifying that you can restore from your >backup and that your media is fresh. This is one of those areas that sink my confidence in predictive modeling and accelerated aging - if it could go any lower. My collection of data CDs, mostly digitized vinyl music and cassette-based audio books plus various specialized backup, number in the thousands, many over 10 years old. I've yet to have that first one refuse to read, at least not any that didn't have physical damage. A couple of years ago I started moving to DVD data storage. No problems there either. One rather extreme experience makes me think that all this stuff about aging is bunk. During my move in up here, one of my data DVDs escaped from custody. It rolled down the edge of my yard where it lay for over 6 months including summer. It was exposed, read side up, to direct sunlight for several hours a day. When I found it, the thing had turned a gorgeous deep royal purple with a pinkish tint around the edges. It was also mud-spattered and had suffered a few scratches on the read side. I figured that it was toast but just for grins I washed off the dirt, stuck it in my cheap Chicom no-name drive and fired off file manager. The disc read perfectly. I copied its contents to my laptop and burned a copy just in case but the original read just fine. It read fast too, with none of the grinding and shaking that the drive does when it's having problems. I suspect that when failures that don't involve damage occur, the cause will turn out to be the plastic sleeves that many people use. perhaps the plasticizer in the sleeve plastic doing something nasty to the discs. I don't use sleeves. I stack 'em back on spindles just like they came from the factory. I've made a number of wooden spindles from dowel (one size fits perfectly in the disc hole) and squares of wood glued together. I don't know if that matters or not but I figure that the factory must think that stacking 'em on spindles is OK so why not? I violate another conventional wisdom. I buy cheap media, usually whatever Sam's Club has on sale. I HAVE had disc/drive compatibility problems but that was a conflict between a specific drive and a specific brand and probably lot of discs. One CD drive I had simply would not digest HP discs even though they were supposed to be high quality. >Heard about how "high security" locks may not be as secure as the >manufacturers claim? Yeah, but I don't take much of that stuff seriously. When I worked for TVA, they'd pay for any schooling that could be even remotely related to the job. I got 'em to pay for me to attend locksmithing night school. I don't have the practical experience of an active full-time locksmith but I HAVE done a lot of hacking and practicing. I can pick a conventional key lock in seconds and open a cheap school locker-style combo lock in minutes. I can open office supply store combination-type fire proof safes in a reasonable amount of time with just manipulation - much faster with an electronic stethoscope. I can't make heads nor tails of this safe's lock. The dial turns as if on ball bearings (probably is). There is no feel and no sound. Most of the dial is shielded so neither the Feynmann nor the Blaze methods can be used. Plus this lock uses 4 digits for the combination which expands the number space hugely. I DID seek the advice of a friend who is a career locksmith before selecting my particular lock setup. He knows his stuff. I suspect that drilling would be the only method in. Even then, a diamond drill would have to be used to defeat the tungsten carbide plate in front of the mechanism. Someone drilling would have to know where my boobytraps are located and only I have that info :-) I put the claim that crypto-grade locks are insecure in the same category as I do theoretical and special case crypto exploits. The span between theory and practice is large, too large for me to worry about. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN Okay, okay, I'll take it back ... UNfuck you! From jim77742 at gmail.com Tue Aug 26 22:14:30 2008 From: jim77742 at gmail.com (Jim Palfreyman) Date: Wed, 27 Aug 2008 12:14:30 +1000 Subject: [time-nuts] I now have a clock accurate to 10E-6!!! In-Reply-To: References: Message-ID: Well here's the photo I promised. I didn't take my time and I didn't use a tripod. But you get the idea. So on the left we have the Siemens Master Clock with the 14mm Riefler pendulum. In the rack from the top we have: 1) 5MHz OCXO backup for the speaking clock. This was used to hold the time if the signal was lost from the central caesium master clock in Victoria. It's a disciplined oscillator and was steered by a 1 KHz tone (based on the caesium reference) down a phone line. 2) Another 5MHz backup unit in case the first failed. 3) The main speaking clock unit. You can set the time, date, daylight savings and leap seconds from here. 4) A simple switch to control which speaking unit was "live". 5) The actual speaking unit. Converts time into voice and sends it back to the main clock unit. Should be two of these, but I only have one. 5) HP 5370B timer counter. 6) HP 3370B function generator. 7) Murray Greenman's GPS clock. It has a 10811 inside and provides the 1PPS for the speaking clock. It also emulates the sound pips of VNG - the now closed Australian short wave time service. At the press of a button it does the announcements that used to happen every 15 minutes "This is VNG, Lyndhurst, Victoria, Australia on 4.5, 7.5 and 12 MHz. VNG is a standard frequency and time signal service of the Australian Telecommunications Division". It does it all in the original voice that the older Australian Ham Radio people know and love. That's because I have the original master tape of that recording and I have digitised it. 8) A lovely old HP nixie tube frequency counter. Still works as if it was bought yesterday. Has a clever device on the right to read frequencies up to 3GHz. All three of the HP counters and oscillators are of course fed off a GPS based frequency reference (HP Z3815A hidden at the back of the rack). 9) This is a part of the speaking clock that I don't use. It takes the time from the main speaking clock unit (3) and creates pips (for example the six pips per hour that was used on the radio stations) and then distributes it down phone lines. 10) This unit receives and decodes the master time signal from a transmission unit that used to be in Victoria (connected to the caesium clock). Since I don't have the transmission unit I cannot use this. I've hot-wired the 1PPS directly into the speaking clock instead. 11) No idea. Came in the rack. Something to do with two-tones. Not used and doesn't power up. To the top right of the rack is the rather nice "mesmeriser" clock kit from Jaycar. It is, of course, sychronised. Below that is a three digit display showing UTC milliseconds. The speaking clock has YY MM DD HH MM SS (in unit 5 in the rack) and so I thought milliseconds was just essential to complete it. To the right and slightly cropped is an old grandfather clock mechanism which I'd hoped to steer via a 1PPS. However the pendulum swings at some bizzare multiple of seconds so I gave up on it. Now I have my Siemens Master Clock I don't care... So there you go - I hope some of you find this post interesting! Regards, Jim 2008/8/26 Neon John > On Mon, 25 Aug 2008 17:40:14 +1000, "Jim Palfreyman" > wrote: > > >Hi Folks, > > > >Well I've had the best weekend since I've just acquired a pendulum clock > >that used to be a telecommunication time standard in the 50s. > > Nice. > > I'd love to have a photo of that with both the clock and the rack of HP > goodies both showing. Move to the right a little, maybe use a tripod and > turn > off the flash to get more uniform lighting and the result would be a > wonderful > contrast between old and new. > > John > -- > John De Armond > See my website for my current email address > http://www.neon-john.com > http://www.johndearmond.com <-- best little blog on the net! > Tellico Plains, Occupied TN > > *fas-cism* (fash'iz'em) n. A system of government that exercises a > dictatorship of the extreme right, typically through the > merging of state and business leadership, together > with belligerent nationalism. -- The American Heritage Dictionary, 1983 > > > _______________________________________________ > time-nuts mailing list -- 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: IMGP4590.jpg Type: image/jpeg Size: 86727 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080827/f10591c2/attachment-0001.jpg From fortime at bellsouth.net Tue Aug 26 22:26:55 2008 From: fortime at bellsouth.net (phil) Date: Tue, 26 Aug 2008 22:26:55 -0400 Subject: [time-nuts] While we're discussing backups... References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com><000601c907a6$22b6ca20$a101a8c0@officemail> Message-ID: <001401c907ec$60356c80$a101a8c0@officemail> ----- Original Message ----- From: "Neon John" To: "Discussion of precise time and frequency measurement" Sent: Tuesday, August 26, 2008 7:55 PM Subject: Re: [time-nuts] While we're discussing backups... > On Tue, 26 Aug 2008 14:04:07 -0400, "phil" wrote: > > >>"tell me what risk I'm exposed to" >>An angry wife ! > > She and my (former) best friend ran away about 5 years ago. Thankfully. > :-) > > John I used "angry wife" only to demonstrate that we often overlook something that we take for granted. From aa8k at comcast.net Tue Aug 26 22:55:42 2008 From: aa8k at comcast.net (Mike Naruta AA8K) Date: Tue, 26 Aug 2008 22:55:42 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> Message-ID: <48B4C22E.3020205@comcast.net> Wife: Maybe he really IS your best friend. :) Powerful lock: We have a big, old house safe that has stopped opening to the combination (the original factory combination). I'm guessing corrosion; debating whether to call a locksmith. Inaccessibility: We're about a half mile from an interstate freeway to an international border. A hazardous material spill could make our backups unavailable forever. Any farm chemicals nearby? My good friend Cliff's wife got angry at him because he was spending too much time on his ham radio. She poured a bottle of glue into his new transceiver. It never worked again. From smace at intt.net Wed Aug 27 00:26:52 2008 From: smace at intt.net (Scott Mace) Date: Tue, 26 Aug 2008 23:26:52 -0500 Subject: [time-nuts] thunderbolt for ntpd or gpsd In-Reply-To: <91981b3e0808101353n2b6706acq61f341b2c8e23de8@mail.gmail.com> References: <200806151159.45824.w.knowles@xtra.co.nz> <489F529A.1030700@intt.net> <91981b3e0808101353n2b6706acq61f341b2c8e23de8@mail.gmail.com> Message-ID: <48B4D78C.8010805@intt.net> Here's another patch that attempts to add leap second parsing to gpsd for the thunderbolt. I used the 0X58 UTC_INFO packet and calculated a the leap second adjustment from delta t LS and delta T LSF store in the current almanac. Then use the presence of the leap second pending alarm and the delta to send ntp a leap second warning. Ignore the parity none stuff unless you own a thunderbolt. The 0x58 trick will probably work with devices that use the 0x41 timing packet, but I don't have a device to test that with. There are other ways to get leap second information that may be more straight forward on these devices, but not on the thunderbolt. You just get a leap second alarm and then have to poll the UTC_INFO out of the almanac to get the leap second delta. The 0x38 poll every 5 seconds is probably overkill, I was just too impatient to wait to see if the receiver automatically sent a 0x58 packet after an almanac change. Probably, the 0x38 needs to run exactly once at startup and then future 0x58 packets will be sent automatically given the 0x8E-A5 mask, but it doesn't seem to hurt anything. This was tested with ntp-4.2.4p4 refclock_shm (no changes needed to ntpd). Scott Chris Kuethe wrote: > On Sun, Aug 10, 2008 at 1:42 PM, Scott Mace wrote: >> ntpshm_put() needs to be called in the 0xab case as well for ntp to work. > > done. > >> --- gpsd/trunk/tsip.c 2008-08-08 23:38:27.000000000 -0500 >> +++ ../gpsd/trunk/tsip.c 2008-08-09 04:14:09.000000000 -0500 >> @@ -65,7 +65,7 @@ >> /* XXX clever heuristic to decide if the parity change is required. >> */ >> session->driver.tsip.parity = session->gpsdata.parity; >> session->driver.tsip.stopbits = session->gpsdata.stopbits; >> - gpsd_set_speed(session, session->gpsdata.baudrate, 'O', 1); >> + gpsd_set_speed(session, session->gpsdata.baudrate, 'N', 1); >> break; >> >> case 1: > > not committing this - i'd prefer a heuristic to autodetect the parity. > i'm open to suggestions on how to do that. > >> @@ -674,6 +674,10 @@ >> >> session->gpsdata.fix.time = session->gpsdata.sentence_time = >> gpstime_to_unix((int)s1, f1) - (double)u1; >> +#ifdef NTPSHM_ENABLE >> + if (session->context->enable_ntpshm) >> + >> (void)ntpshm_put(session,session->gpsdata.sentence_time+0.075); >> +#endif >> mask |= TIME_SET; >> } > > just committed this part... > > -------------- next part -------------- A non-text attachment was scrubbed... Name: gpsd-thunderbolt-leapsecond.patch Type: text/x-patch Size: 10920 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080826/ae9efefe/attachment.bin From rexa at sonic.net Wed Aug 27 01:01:42 2008 From: rexa at sonic.net (Rex) Date: Tue, 26 Aug 2008 22:01:42 -0700 Subject: [time-nuts] While we're discussing backups... In-Reply-To: References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> <91981b3e0808261117sba917e6mc19ebbbe35364d87@mail.gmail.com> Message-ID: <48B4DFB6.7000907@sonic.net> Neon John wrote: > This is one of those areas that sink my confidence in predictive modeling and > accelerated aging - if it could go any lower. > > My collection of data CDs, mostly digitized vinyl music and cassette-based > audio books plus various specialized backup, number in the thousands, many > over 10 years old. I've yet to have that first one refuse to read, at least > not any that didn't have physical damage. > > A couple of years ago I started moving to DVD data storage. No problems there > either. One rather extreme experience makes me think that all this stuff > about aging is bunk. > > In general I agree with you but I have one case where discs became trash. It must have been from a problem in the manufacture. I bought a couple recorded video DVDs from a small vendor. I'm not sure if they were burned, but I suspect they were. (As opposed to pressed - or what ever the right term is for the high volume manufacture method.) They were fine when I played them randomly over the first several months. Then I lost interest and didn't try to play them again for at least a year, maybe a couple years. When I finally tried again they were useless. The inner shiny data surface had turned dull brown; more-so at the edges, but all of the two disks were unreadable. So I know of at least one case where (I assume) some problem in the manufacturing process left these disks with a very short lifetime. These were not backups, not critical and no big loss, but the moral, I guess, is don't buy cheap no-name media for your backups. I believe there is an archival grade for DVDs and CDs. It might be worth using if the data is important to you and you expect to keep it on this media for a long time. Checking the backups periodically for signs of degradation is not a bad idea, unless the backups are only needed over a short period. This monitoring has been mentioned before, but requires the same kind of discipline needed as to make the backups in the first place. From df6jb at ulrich-bangert.de Wed Aug 27 08:43:00 2008 From: df6jb at ulrich-bangert.de (Ulrich Bangert) Date: Wed, 27 Aug 2008 14:43:00 +0200 Subject: [time-nuts] 10811A versus 10811-60111 In-Reply-To: <20080826.102233.-355005.2.cdelect@juno.com> Message-ID: <227B3D52CE674F3780D0005BB79E9D1A@athlon> Corby, the FTS specs for their FTS1000A, FTS1200, FTS1002A and FTS1003A name short term stabilities for all four oscillators to be 1E-12 @ 1,10,100 s. I have always believed that these specs are kind of "conservative" ones so that your FTS1200 #2 fits them VERY well while FTS1200 #1 barely meets the specs. Is there any idea on why these two oscillators behave that different? Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces at febo.com > [mailto:time-nuts-bounces at febo.com] Im Auftrag von corby d dawson > Gesendet: Dienstag, 26. August 2008 19:23 > An: time-nuts at febo.com > Betreff: Re: [time-nuts] 10811A versus 10811-60111 > > > Hi, > > I have had the occasion recently to measure the aging and > short term stability of a bunch of oscillators. > > Measurements were against an EFOS-2 Hydrogen Maser. > > I thought that the results between 10811A (-60109 variant) > and the 10811-60111 might be of interest to some. > > All oscillators had aging below 5X10-10/day. > > As you can see the short term stability of the -60111 > compares favorably with the 10811A. > > I'll be making some measurements on the -60158 variants and > some motorola units soon. > > Cheers! > Corby Dawson > > > QUARTZ 1 SEC. 10 SEC. 100 SEC. 1K SEC. (ALL HAD AGING BELOW > 5X10-5/DAY) > ------------------------------------------------ > 10811-60109 6.11-12 2.52-12 8.78-12 > 10811-60109 1.65-12 1.91-12 9.79-12 > 10811-60109 1.65-12 1.99-12 1.11-12 > 10811-60109 5.47-12 1.16-12 2.38-12 > 105 STYLE #T 7.60-13 2.01-12 3.94-12 > 10811-60111 1.27-12 2.65-12 1.93-12 > 105 STYLE #2 1.14-12 1.57-12 2.26-12 > 105 STYLE #3 1.31-12 1.58-12 2.68-12 > 10811-60111 3.04-12 5.54-12 1.47-12 > 105 STYLE #4 1.38-12 3.49-12 4.84-12 > 10811-60109 2.05-12 2.89-12 3.24-12 > 10811-60111 1.36-12 1.17-12 1.75-12 > 105 STYLE #5 1.14-12 2.09-12 2.51-12 > FTS 1200 #1 7.14-13 1.48-12 1.92-12 > 10543A 2.86-11 1.05-11 1.63-11 > FTS 1200 #2 2.99-13 4.30-13 7.69-13 8.65-13 > 10544A 4.08-12 2.95-12 7.79-12 > 10811-60111 1.24-12 2.10-12 2.09-12 > 10811-60111 1.48-12 1.59-12 1.54-12 > 10544A 1.89-12 2.99-12 5.01-12 > 105 style #6 2.88-12 2.88-12 7.37-12 > 105 style #7 9.69-13 2.30-12 3.49-12 > 10544-60511 8.20-13 2.11-12 2.51-12 > Piezo clone 2.57-12 2.23-12 2.17-12 > 5060A osconly 4.04-12 5.94-12 8.42-12 1.30-11 > 10811-60111 2.59-12 3.87-12 5.77-12 > > -60109spec 2.50-12 5.00-12 1.00-11 > -60111spec <1.00-12 * * > 10811Aspec 5.00-12 5.00-12 1.00-11 > *not specified > ____________________________________________________________ > Click to find information on your credit score and your > credit report. > http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m2PczsRdNFK t2GBl1YDtgaQ4QFPJm37HTYhIBtnzDllyvQl/ _______________________________________________ time-nuts mailing list -- 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 Aug 27 13:21:44 2008 From: cdelect at juno.com (corby d dawson) Date: Wed, 27 Aug 2008 10:21:44 -0700 Subject: [time-nuts] 10811A vs 10811-60111 Message-ID: <20080827.102145.-647299.0.cdelect@juno.com> Ulrich, The 1200 #1 is built into a GR1115B that had a defective oscillator assy. It could be that the power supply and or the EFC tuning circuit which is hooked to the manual adjust pot is causing the difference. If I get a chance I'll pull the oscillator and retest it and se what happens. I do however have a 1000A that is being tested in the same setup as the "good" 1200 and so far it is not doing very well. Also I meant to thank you for your help with your plotter program and the added decade value Allen deviation you installed. It has made the testing a lot easier. Best Regards, Corby Dawson ____________________________________________________________ Bills adding up? Click here for free information on payday loans. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m3aOdw2zJYUhRN8ZONwp40YEDAkEVmGNBVkCGzEi4FUFq97/ From cdelect at juno.com Wed Aug 27 13:51:48 2008 From: cdelect at juno.com (corby d dawson) Date: Wed, 27 Aug 2008 10:51:48 -0700 Subject: [time-nuts] Efratom FRKH Message-ID: <20080827.105149.-647299.1.cdelect@juno.com> Hi, Anyone have a good Efratom FRKH module. The version with the row of exposed pins vice the one with the multipin 3 row connector? Thanks, Corby Dawson ____________________________________________________________ Love Graphic Design? Find a school near you. Click Now. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3oLKlkoxnarfeAPOrkPPKuPvoe5lfDxijdApcqviN3f53HkV/ From jgd at johngsbbq.com Wed Aug 27 15:09:06 2008 From: jgd at johngsbbq.com (Neon John) Date: Wed, 27 Aug 2008 15:09:06 -0400 Subject: [time-nuts] While we're discussing backups... In-Reply-To: <48B4C22E.3020205@comcast.net> References: <4t98b49ps4ecdv9kfad5qqa4hpi3dnvasu@4ax.com> <48B4C22E.3020205@comcast.net> Message-ID: On Tue, 26 Aug 2008 22:55:42 -0400, Mike Naruta AA8K wrote: >Wife: Maybe he really IS your best friend. :) Probably so. Actually I had a great marriage for 25 of the 27 years. Then menopause hit with a vengeance. I sure am glad I'm an outie instead of an innie. I'd not wish that on anyone. We split amicably and still chat occasionally. >Powerful lock: We have a big, old house safe >that has stopped opening to the combination >(the original factory combination). I'm guessing >corrosion; debating whether to call a locksmith. Either that or the combination setting mechanism has broken or come loose. A locksmith is probably your best bet unless you just want a project to play with. He'll probably have to drill the lock. Drilling templates is one of the things highly guarded by the high priests of the profession. A good 'smith can install a new lock so that the hole is plugged suitably and all signs of the drilling are hidden. Of course, you DO need to make sure you're memory ADEV isn't too bad :-) Bad memory's the most common reason for locksmith calls for safe openings. You might take a look at Matt Blaze's paper on safe cracking here: http://www.crypto.com/papers/safelocks.pdf His technique near the end of the paper should work well for you if you've either slipped a few digits in your memory or a setting wheel has slipped a little. >Inaccessibility: We're about a half mile from >an interstate freeway to an international border. >A hazardous material spill could make our backups >unavailable forever. Any farm chemicals nearby? Nah. My place is a private inholding smack in the middle of the Cherokee National Forest. Twenty five miles in any direction to any other civilization. The ranger nazis write people tickets for washing their hands in the river. The worst chemical here is probably the bleach that some folks use to chlorinate their water. Basically heaven on earth! >My good friend Cliff's wife got angry at him >because he was spending too much time on his >ham radio. She poured a bottle of glue into >his new transceiver. It never worked again. That's just cause for what is known in the legal profession as "commendable homicide"! I had a now-deceased ham friend whose wife would do stuff like that. I always stood in drop-jaw amazement when I heard of her latest escapade. I can't imagine getting mad enough at my wife to actually tear up her stuff. Takes all types, I guess. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN There is much pleasure in useless knowledge. ?Bertrand Russell From wje at quackers.net Wed Aug 27 18:12:02 2008 From: wje at quackers.net (wje) Date: Wed, 27 Aug 2008 18:12:02 -0400 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? Message-ID: <48B5D132.6030501@quackers.net> I just got one of the new networked GPIB controllers, and I've been having some issues. I'm not sure if it's the Prologix or the instruments, or both. With the 5370A, I can get samples for some period of time ranging from about 2 to 4 hours before the GPIB controller stops responding. I suspect this one might be the 5370A -488 controller bug I've heard of. However, there is no way to recover without power-cycling the Prologix. Even if this is the 5370A, the Prologix should really have an asynchronous reset capability. With the 5334A, I can get samples for as long as I want, no problem. However, if I set the 5334A to 'WA1' mode, which is supposed to wait until the counter is addressed before taking each sample, what happens is that I can read one value. Every successive read returns the same value; the 5334A never triggers for a new sample. Either I don't understand the behavior of WA1, although HP's sample program indicates that what I've described is proper, or there is some incompatibility between the Prologix and the 5334A. Unfortunately, the documentation for the Prologix is scanty at best. There is no description of the actual IEEE-488 handshake process that's going on. For example, does the Prologix do an unlisten after a read? The HP docs seem to indicate that in WA1 mode, a sample starts when the 5334A is addressed. So, if it's never unlistened, perhaps it never takes a new sample? Any thoughts or suggestions would be appreciated. -- Bill Ezell ---------- They said 'Windows or better' so I used Linux. From support at prologix.biz Wed Aug 27 18:31:25 2008 From: support at prologix.biz (Prologix) Date: Wed, 27 Aug 2008 15:31:25 -0700 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: <48B5D132.6030501@quackers.net> Message-ID: Bill, How are you reading from 5334A? Is the read-after-write mode OFF? I recommend the following sequence: ++auto 0 -- turn off read-after-write ++read eoi -- read until EOI is asserted by the instrument ++read eoi .... (If your instrument does not assert EOI, specify a character to terminate ++read command. See manual for details.) Yes, ++read will address the instrument to talk, read any output, and then address it to listen. We are testing an update that resets the controller if it detects a hung GPIB bus. I can send that to you offline. Regards, Abdul -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of wje Sent: Wednesday, August 27, 2008 3:12 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? I just got one of the new networked GPIB controllers, and I've been having some issues. I'm not sure if it's the Prologix or the instruments, or both. With the 5370A, I can get samples for some period of time ranging from about 2 to 4 hours before the GPIB controller stops responding. I suspect this one might be the 5370A -488 controller bug I've heard of. However, there is no way to recover without power-cycling the Prologix. Even if this is the 5370A, the Prologix should really have an asynchronous reset capability. With the 5334A, I can get samples for as long as I want, no problem. However, if I set the 5334A to 'WA1' mode, which is supposed to wait until the counter is addressed before taking each sample, what happens is that I can read one value. Every successive read returns the same value; the 5334A never triggers for a new sample. Either I don't understand the behavior of WA1, although HP's sample program indicates that what I've described is proper, or there is some incompatibility between the Prologix and the 5334A. Unfortunately, the documentation for the Prologix is scanty at best. There is no description of the actual IEEE-488 handshake process that's going on. For example, does the Prologix do an unlisten after a read? The HP docs seem to indicate that in WA1 mode, a sample starts when the 5334A is addressed. So, if it's never unlistened, perhaps it never takes a new sample? Any thoughts or suggestions would be appreciated. -- 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. From jmiles at pop.net Wed Aug 27 18:39:07 2008 From: jmiles at pop.net (John Miles) Date: Wed, 27 Aug 2008 15:39:07 -0700 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: <48B5D132.6030501@quackers.net> Message-ID: > > I just got one of the new networked GPIB controllers, and I've been > having some issues. I'm not sure if it's the Prologix or the > instruments, or both. > > With the 5370A, I can get samples for some period of time ranging from > about 2 to 4 hours before the GPIB controller stops responding. I > suspect this one might be the 5370A -488 controller bug I've heard of. > However, there is no way to recover without power-cycling the Prologix. > Even if this is the 5370A, the Prologix should really have an > asynchronous reset capability. > > With the 5334A, I can get samples for as long as I want, no problem. > However, if I set the 5334A to 'WA1' mode, which is supposed to wait > until the counter is addressed before taking each sample, what happens > is that I can read one value. Every successive read returns the same > value; the 5334A never triggers for a new sample. Either I don't > understand the behavior of WA1, although HP's sample program indicates > that what I've described is proper, or there is some incompatibility > between the Prologix and the 5334A. > > Unfortunately, the documentation for the Prologix is scanty at best. > There is no description of the actual IEEE-488 handshake process that's > going on. For example, does the Prologix do an unlisten after a read? > The HP docs seem to indicate that in WA1 mode, a sample starts when the > 5334A is addressed. So, if it's never unlistened, perhaps it never takes > a new sample? > > Any thoughts or suggestions would be appreciated. Bill, what commands and queries are you using with the 5370A? I have a couple of those new Prologix LAN dongles here and could try to repro it here on my 5370B, if it turns out that Abdul needs to see it happen in person. I don't have a 5334A, but it might help to send it a ++trg trigger command. If not, you'd probably need to switch auto-read mode off for that one, and use manual ++read commands. -- john, KE5FX From wje at quackers.net Wed Aug 27 19:13:30 2008 From: wje at quackers.net (wje) Date: Wed, 27 Aug 2008 19:13:30 -0400 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: References: Message-ID: <48B5DF9A.8040003@quackers.net> YI don't use read-after-write, and I explicitly set it off before reading. However, I did try it once just for fun, and it does work as expected. The 5334 doesn't seem to assert eoi, so I do a '++read 10', which works just fine except for the WA1 strangeness. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Prologix wrote: > Bill, > > How are you reading from 5334A? Is the read-after-write mode OFF? > I recommend the following sequence: > > ++auto 0 -- turn off read-after-write > ++read eoi -- read until EOI is asserted by the instrument > ++read eoi > .... > > (If your instrument does not assert EOI, specify a character to terminate > ++read command. See manual for details.) > > Yes, ++read will address the instrument to talk, read any output, and then > address it to listen. > > We are testing an update that resets the controller if it detects a hung > GPIB bus. I can send that to you offline. > > Regards, > Abdul > > > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of wje > Sent: Wednesday, August 27, 2008 3:12 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? > > I just got one of the new networked GPIB controllers, and I've been > having some issues. I'm not sure if it's the Prologix or the > instruments, or both. > > With the 5370A, I can get samples for some period of time ranging from > about 2 to 4 hours before the GPIB controller stops responding. I > suspect this one might be the 5370A -488 controller bug I've heard of. > However, there is no way to recover without power-cycling the Prologix. > Even if this is the 5370A, the Prologix should really have an > asynchronous reset capability. > > With the 5334A, I can get samples for as long as I want, no problem. > However, if I set the 5334A to 'WA1' mode, which is supposed to wait > until the counter is addressed before taking each sample, what happens > is that I can read one value. Every successive read returns the same > value; the 5334A never triggers for a new sample. Either I don't > understand the behavior of WA1, although HP's sample program indicates > that what I've described is proper, or there is some incompatibility > between the Prologix and the 5334A. > > Unfortunately, the documentation for the Prologix is scanty at best. > There is no description of the actual IEEE-488 handshake process that's > going on. For example, does the Prologix do an unlisten after a read? > The HP docs seem to indicate that in WA1 mode, a sample starts when the > 5334A is addressed. So, if it's never unlistened, perhaps it never takes > a new sample? > > Any thoughts or suggestions would be appreciated. > > From wje at quackers.net Wed Aug 27 19:20:52 2008 From: wje at quackers.net (wje) Date: Wed, 27 Aug 2008 19:20:52 -0400 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: References: Message-ID: <48B5E154.7020905@quackers.net> If the 5370A problem is actually the 5370A gpib controller bug, then I don't think it can be reproduced with the 5370B; I'm pretty sure that was fixed in the B model. However, if you want to give it a try, here's what I do (you'll have to interpret, but it should be pretty clear): Sorry for the strange syntax, but that's for a Java control program I originally wrote to talk to my Solartron 7081 meter. The program is just sending out the literal string in the Sends, terminated with a newline. The Read command is sending '++read 10'. The timeout in the Read has nothing to do with the Prologix timeout, that's a timeout handled by my interpreter. Bill Ezell ---------- They said 'Windows or better' so I used Linux. John Miles wrote: I just got one of the new networked GPIB controllers, and I've been having some issues. I'm not sure if it's the Prologix or the instruments, or both. With the 5370A, I can get samples for some period of time ranging from about 2 to 4 hours before the GPIB controller stops responding. I suspect this one might be the 5370A -488 controller bug I've heard of. However, there is no way to recover without power-cycling the Prologix. Even if this is the 5370A, the Prologix should really have an asynchronous reset capability. With the 5334A, I can get samples for as long as I want, no problem. However, if I set the 5334A to 'WA1' mode, which is supposed to wait until the counter is addressed before taking each sample, what happens is that I can read one value. Every successive read returns the same value; the 5334A never triggers for a new sample. Either I don't understand the behavior of WA1, although HP's sample program indicates that what I've described is proper, or there is some incompatibility between the Prologix and the 5334A. Unfortunately, the documentation for the Prologix is scanty at best. There is no description of the actual IEEE-488 handshake process that's going on. For example, does the Prologix do an unlisten after a read? The HP docs seem to indicate that in WA1 mode, a sample starts when the 5334A is addressed. So, if it's never unlistened, perhaps it never takes a new sample? Any thoughts or suggestions would be appreciated. Bill, what commands and queries are you using with the 5370A? I have a couple of those new Prologix LAN dongles here and could try to repro it here on my 5370B, if it turns out that Abdul needs to see it happen in person. I don't have a 5334A, but it might help to send it a ++trg trigger command. If not, you'd probably need to switch auto-read mode off for that one, and use manual ++read commands. -- john, KE5FX _______________________________________________ time-nuts mailing list -- [1]time-nuts at febo.com To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts at febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From support at prologix.biz Wed Aug 27 19:25:34 2008 From: support at prologix.biz (Prologix) Date: Wed, 27 Aug 2008 16:25:34 -0700 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: <48B5DF9A.8040003@quackers.net> Message-ID: You could try explicitly triggering with ++trg followed by ++read 10. -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of wje Sent: Wednesday, August 27, 2008 4:14 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? YI don't use read-after-write, and I explicitly set it off before reading. However, I did try it once just for fun, and it does work as expected. The 5334 doesn't seem to assert eoi, so I do a '++read 10', which works just fine except for the WA1 strangeness. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Prologix wrote: > Bill, > > How are you reading from 5334A? Is the read-after-write mode OFF? > I recommend the following sequence: > > ++auto 0 -- turn off read-after-write > ++read eoi -- read until EOI is asserted by the instrument > ++read eoi > .... > > (If your instrument does not assert EOI, specify a character to terminate > ++read command. See manual for details.) > > Yes, ++read will address the instrument to talk, read any output, and then > address it to listen. > > We are testing an update that resets the controller if it detects a hung > GPIB bus. I can send that to you offline. > > Regards, > Abdul > > > > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On > Behalf Of wje > Sent: Wednesday, August 27, 2008 3:12 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? > > I just got one of the new networked GPIB controllers, and I've been > having some issues. I'm not sure if it's the Prologix or the > instruments, or both. > > With the 5370A, I can get samples for some period of time ranging from > about 2 to 4 hours before the GPIB controller stops responding. I > suspect this one might be the 5370A -488 controller bug I've heard of. > However, there is no way to recover without power-cycling the Prologix. > Even if this is the 5370A, the Prologix should really have an > asynchronous reset capability. > > With the 5334A, I can get samples for as long as I want, no problem. > However, if I set the 5334A to 'WA1' mode, which is supposed to wait > until the counter is addressed before taking each sample, what happens > is that I can read one value. Every successive read returns the same > value; the 5334A never triggers for a new sample. Either I don't > understand the behavior of WA1, although HP's sample program indicates > that what I've described is proper, or there is some incompatibility > between the Prologix and the 5334A. > > Unfortunately, the documentation for the Prologix is scanty at best. > There is no description of the actual IEEE-488 handshake process that's > going on. For example, does the Prologix do an unlisten after a read? > The HP docs seem to indicate that in WA1 mode, a sample starts when the > 5334A is addressed. So, if it's never unlistened, perhaps it never takes > a new sample? > > Any thoughts or suggestions would be appreciated. > > _______________________________________________ time-nuts mailing list -- 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 wje at quackers.net Wed Aug 27 19:34:54 2008 From: wje at quackers.net (wje) Date: Wed, 27 Aug 2008 19:34:54 -0400 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: References: Message-ID: <48B5E49E.4070105@quackers.net> That does the trick, thanks. Interestingly, the HP manual doesn't discuss group-execute-trigger at all. It's possible that the HP-85 programmable controllers would do a trigger before a read; all of the examples in the 5334A manual are written for that controller. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Prologix wrote: You could try explicitly triggering with ++trg followed by ++read 10. -----Original Message----- From: [1]time-nuts-bounces at febo.com [[2]mailto:time-nuts-bounces at febo.com] On Behalf Of wje Sent: Wednesday, August 27, 2008 4:14 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? YI don't use read-after-write, and I explicitly set it off before reading. However, I did try it once just for fun, and it does work as expected. The 5334 doesn't seem to assert eoi, so I do a '++read 10', which works just fine except for the WA1 strangeness. Bill Ezell ---------- They said 'Windows or better' so I used Linux. Prologix wrote: Bill, How are you reading from 5334A? Is the read-after-write mode OFF? I recommend the following sequence: ++auto 0 -- turn off read-after-write ++read eoi -- read until EOI is asserted by the instrument ++read eoi .... (If your instrument does not assert EOI, specify a character to terminate ++read command. See manual for details.) Yes, ++read will address the instrument to talk, read any output, and then address it to listen. We are testing an update that resets the controller if it detects a hung GPIB bus. I can send that to you offline. Regards, Abdul -----Original Message----- From: [3]time-nuts-bounces at febo.com [[4]mailto:time-nuts-bounces at febo.com] On Behalf Of wje Sent: Wednesday, August 27, 2008 3:12 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? I just got one of the new networked GPIB controllers, and I've been having some issues. I'm not sure if it's the Prologix or the instruments, or both. With the 5370A, I can get samples for some period of time ranging from about 2 to 4 hours before the GPIB controller stops responding. I suspect this one might be the 5370A -488 controller bug I've heard of. However, there is no way to recover without power-cycling the Prologix. Even if this is the 5370A, the Prologix should really have an asynchronous reset capability. With the 5334A, I can get samples for as long as I want, no problem. However, if I set the 5334A to 'WA1' mode, which is supposed to wait until the counter is addressed before taking each sample, what happens is that I can read one value. Every successive read returns the same value; the 5334A never triggers for a new sample. Either I don't understand the behavior of WA1, although HP's sample program indicates that what I've described is proper, or there is some incompatibility between the Prologix and the 5334A. Unfortunately, the documentation for the Prologix is scanty at best. There is no description of the actual IEEE-488 handshake process that's going on. For example, does the Prologix do an unlisten after a read? The HP docs seem to indicate that in WA1 mode, a sample starts when the 5334A is addressed. So, if it's never unlistened, perhaps it never takes a new sample? Any thoughts or suggestions would be appreciated. _______________________________________________ time-nuts mailing list -- [5]time-nuts at febo.com To unsubscribe, go to [6]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [7]time-nuts at febo.com To unsubscribe, go to [8]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts-bounces at febo.com 2. mailto:time-nuts-bounces at febo.com 3. mailto:time-nuts-bounces at febo.com 4. mailto:time-nuts-bounces at febo.com 5. mailto:time-nuts at febo.com 6. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 7. mailto:time-nuts at febo.com 8. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From wje at quackers.net Wed Aug 27 19:45:12 2008 From: wje at quackers.net (wje) Date: Wed, 27 Aug 2008 19:45:12 -0400 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: <48B5E49E.4070105@quackers.net> References: <48B5E49E.4070105@quackers.net> Message-ID: <48B5E708.1090401@quackers.net> Also, if it's of any use, the HP-85 controller does an unlisten, my-talk-addr, listen-address-x for each read. There's no mention of the HP-85 doing an automatic group-execute-trigger, and none of the examples issue an explicit trigger. There is one sentence in the 5334 manual that says a g-e-t will trigger a new measurement, which is what I would expect. Bill Ezell ---------- They said 'Windows or better' so I used Linux. wje wrote: > That does the trick, thanks. Interestingly, the HP manual doesn't > discuss group-execute-trigger at all. It's possible that the HP-85 > programmable controllers would do a trigger before a read; all of the > examples in the 5334A manual are written for that controller. > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > Prologix wrote: > > You could try explicitly triggering with ++trg followed by ++read 10. > > > -----Original Message----- > From: [1]time-nuts-bounces at febo.com [[2]mailto:time-nuts-bounces at febo.com] On > Behalf Of wje > Sent: Wednesday, August 27, 2008 4:14 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? > > YI don't use read-after-write, and I explicitly set it off before > reading. However, I did try it once just for fun, and it does work as > expected. > > The 5334 doesn't seem to assert eoi, so I do a '++read 10', which works > just fine except for the WA1 strangeness. > > Bill Ezell > ---------- > They said 'Windows or better' > so I used Linux. > > > > Prologix wrote: > > Bill, > > How are you reading from 5334A? Is the read-after-write mode OFF? > I recommend the following sequence: > > ++auto 0 -- turn off read-after-write > ++read eoi -- read until EOI is asserted by the instrument > ++read eoi > .... > > (If your instrument does not assert EOI, specify a character to terminate > ++read command. See manual for details.) > > Yes, ++read will address the instrument to talk, read any output, and then > address it to listen. > > We are testing an update that resets the controller if it detects a hung > GPIB bus. I can send that to you offline. > > Regards, > Abdul > > > > -----Original Message----- > From: [3]time-nuts-bounces at febo.com [[4]mailto:time-nuts-bounces at febo.com] On > Behalf Of wje > Sent: Wednesday, August 27, 2008 3:12 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? > > I just got one of the new networked GPIB controllers, and I've been > having some issues. I'm not sure if it's the Prologix or the > instruments, or both. > > With the 5370A, I can get samples for some period of time ranging from > about 2 to 4 hours before the GPIB controller stops responding. I > suspect this one might be the 5370A -488 controller bug I've heard of. > However, there is no way to recover without power-cycling the Prologix. > Even if this is the 5370A, the Prologix should really have an > asynchronous reset capability. > > With the 5334A, I can get samples for as long as I want, no problem. > However, if I set the 5334A to 'WA1' mode, which is supposed to wait > until the counter is addressed before taking each sample, what happens > is that I can read one value. Every successive read returns the same > value; the 5334A never triggers for a new sample. Either I don't > understand the behavior of WA1, although HP's sample program indicates > that what I've described is proper, or there is some incompatibility > between the Prologix and the 5334A. > > Unfortunately, the documentation for the Prologix is scanty at best. > There is no description of the actual IEEE-488 handshake process that's > going on. For example, does the Prologix do an unlisten after a read? > The HP docs seem to indicate that in WA1 mode, a sample starts when the > 5334A is addressed. So, if it's never unlistened, perhaps it never takes > a new sample? > > Any thoughts or suggestions would be appreciated. > > > > _______________________________________________ > time-nuts mailing list -- [5]time-nuts at febo.com > To unsubscribe, go to > [6]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [7]time-nuts at febo.com > To unsubscribe, go to [8]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > References > > 1. mailto:time-nuts-bounces at febo.com > 2. mailto:time-nuts-bounces at febo.com > 3. mailto:time-nuts-bounces at febo.com > 4. mailto:time-nuts-bounces at febo.com > 5. mailto:time-nuts at febo.com > 6. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > 7. mailto:time-nuts at febo.com > 8. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > _______________________________________________ > time-nuts mailing list -- 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 steve at borisone.demon.co.uk Wed Aug 27 20:01:19 2008 From: steve at borisone.demon.co.uk (S J Roberts) Date: Thu, 28 Aug 2008 01:01:19 +0100 Subject: [time-nuts] HP106 manual / circuit Message-ID: Hi all. I've been lurking for a while now - receiving the digests. Just starting on the time-nut trail with a couple of z3801a's, an FRS-C rubidium, a couple of adret 5104's and a FEI contraption with a rubidium disciplining an external crystal oscillator giving 5Mhz out. Does anyone know where I can get a manual/circuit for the old HP106 standard? as the outer oven current is off the meter scale and never settles. Cheers Steve Roberts From neilsan at tpg.com.au Wed Aug 27 21:36:15 2008 From: neilsan at tpg.com.au (Neil Sandford) Date: Thu, 28 Aug 2008 11:36:15 +1000 Subject: [time-nuts] Trimble Thunderbolt GPS Message-ID: <002f01c908ae$78653480$a5d1f23c@sandford> Hi All Just subscribed to Time-nuts as I would like to be placed on the list to obtain a Trimble Thunderbolt GPS. Please advise what further action and/or contact may be required by me. 73 Neil VK2EI From kanab2004 at kanab.net Wed Aug 27 20:50:38 2008 From: kanab2004 at kanab.net (Gerry Glauser) Date: Wed, 27 Aug 2008 18:50:38 -0600 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? Message-ID: Bill, I recall there was some question on the Prologix "unlisten", but I suspect you're seeing a 5334A issue. While testing my driver at max 5334A throughput, I found found you cannot trust a ++read until the status byte returns data ready, else you may get the previous reading. That would happen even at reduced throughput, depending on gate time. So I send a trigger, then loop on status byte (with timeout of gate time+), then read. Because that is necessary, I didn't see any advantage to the WA1 mode. Gerry >wje >With the 5334A, I can get samples for as long as I want, no problem. >However, if I set the 5334A to 'WA1' mode, which is supposed to wait >until the counter is addressed before taking each sample, what happens >is that I can read one value. Every successive read returns the same >value; the 5334A never triggers for a new sample. Either I don't >understand the behavior of WA1, although HP's sample program indicates >that what I've described is proper, or there is some incompatibility >between the Prologix and the 5334A. From kirbybq at bellsouth.net Thu Aug 28 00:40:02 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Wed, 27 Aug 2008 23:40:02 -0500 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: <20080827.105149.-647299.1.cdelect@juno.com> References: <20080827.105149.-647299.1.cdelect@juno.com> Message-ID: <48B62C22.6060103@bellsouth.net> I received the TAPR group buy Trimble Thunderbolt receiver. It appears to be hard of hearing when compared to an old Motorola Oncore VP or M12. It is tracking 4 sats, when the Old VP is tracking 7 sats, etc. Looks like I am going to have to amplifiy just its port.... Anyone else notice this ? Brian - KD4FM From ghane0 at gmail.com Thu Aug 28 06:10:03 2008 From: ghane0 at gmail.com (Sanjeev Gupta) Date: Thu, 28 Aug 2008 18:10:03 +0800 Subject: [time-nuts] TBolt question In-Reply-To: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> References: <8CAD3B35D537481-D94-62F7@webmail-nd15.sysops.aol.com> Message-ID: <158106a0808280310n5e413f12w142417fda0afbdcf@mail.gmail.com> Hi, Is there a definitive webpage which lists the Thunderbolt offer from TAPR? I cannot find anything via google on the TAPR site. Thanks -- Sanjeev Gupta +65 98551208 On Sun, Aug 24, 2008 at 11:48 AM, wrote: > Hi, > > Just received my TBolt from the TAPR buy and have a quick(?) question: > tvb indicated that the unit builds were from ~2005, and indeed, the photo > of the TAPR package on Leapsecond.com shows a TBolt from 2005 revision 'E'. > The unit I received is build 2002 revision 'B'. Anyone know of differences > in the revisions, and whether the OCXO (which Tom found surprisingly > excellent) are the same? > Thanks, > Jerry > From j.bastemeijer at tudelft.nl Thu Aug 28 07:13:01 2008 From: j.bastemeijer at tudelft.nl (Jeroen Bastemeijer) Date: Thu, 28 Aug 2008 13:13:01 +0200 Subject: [time-nuts] Nice LORAN-book Message-ID: <48B6883D.4040802@tudelft.nl> Dear All, Maybe it was mentioned before, but by accident I found (rediscovered?) this book: "New potential of low-frequency radionavigation in the 21st century" It was a PhD-thesis written (in 2006) on the university I'm working for. The book can be downloaded from this site: http://www.vhl.tudelft.nl/pelgrum/formulier.adp It is a 300 pages PDF-document. Chapter 5 is about LORAN H-field antennas. Maybe it gives some answers to people who are interested in those kind of antennas. 73 Jeroen PE1RGE -------------- next part -------------- A non-text attachment was scrubbed... Name: j_bastemeijer.vcf Type: text/x-vcard Size: 355 bytes Desc: not available Url : http://www.febo.com/pipermail/time-nuts/attachments/20080828/420f1afa/attachment.vcf From holrum at hotmail.com Thu Aug 28 13:05:20 2008 From: holrum at hotmail.com (Mark Sims) Date: Thu, 28 Aug 2008 17:05:20 +0000 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: References: Message-ID: The Thunderbolt does not seem to be the most sensitive receiver around, but it does not seem particularly bad. Sensitivity in a time receiver can be a bad thing... more sensitivity tends to make it more susceptible to multipath, etc. These things were meant to be mounted on cell towers, etc where they have a pretty clear view of the sky. Once you have that, you don't need high sensitivity. Also their proximity to high power RF transmitters makes overly sensitive front ends a problem. On the subject of GPS amplifiers... adding external amplification to a GPS may not improve its performance and can actually degrade it. All amplifiers amplify signal and noise, plus distort everything in the process. (fundamental laws of the universe: 1) You can't get something for nothing, 2) You can't break even, 3) You'll die trying) Ideally, you want the amplifier at the antenna and you want the amplification to match the cable loss and no more. Generally GPS receivers with poor sensitivity have poorly designed front ends or signal processing. Yelling in their ears won't make them work any better. ---------------------------------------- _________________________________________________________________ Get ideas on sharing photos from people like you. Find new ways to share. http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 From had at to-way.com Thu Aug 28 13:09:58 2008 From: had at to-way.com (Had) Date: Thu, 28 Aug 2008 10:09:58 -0700 Subject: [time-nuts] PTS Meter Message-ID: <20080828171206.9295D19281E@mail-in04.adhost.com> Hi Gang, Just picked up a PTS-160 that seems to be working fine except for the front panel meter. Appears to have either an open coil or a open connection at a pivot point. No DC continuity through the meter. Anybody have a dead synthesizer that might entertain a deal on the meter? Thanks, Had, K7MLR From holrum at hotmail.com Thu Aug 28 13:18:21 2008 From: holrum at hotmail.com (Mark Sims) Date: Thu, 28 Aug 2008 17:18:21 +0000 Subject: [time-nuts] time-nuts Digest, Vol 49, Issue 83 In-Reply-To: References: Message-ID: I am only really familiar with the 5650A/5680A with the AD9830A DDS chip that responds to the ASCII "S/E/F" commands. This manual talks about a 5680A with a different set of commands: http://tonga.globat.com/~ko4bb.com/Manuals/5)_GPS_Timing/FE5680A_Opt2_TechManRevised.doc Hopefully it will let you talk to your unit... ---------------------------------------- Mark, which pot is it ? Rex and myself bought units that were not programmable. Both of us have tweaked the pots and have not seen any change in drift. I turned pots 1 turn per day and did phase observations, over the course of a week. They guy that sold these units on ebay claimed they were programmable but could not produce the information. Its been noted he has changed his ebay user name about every 6 months (that might give you an idea about his operation - he also complained about whiny time-nuts postings about his operation). _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008 From holrum at hotmail.com Thu Aug 28 14:27:28 2008 From: holrum at hotmail.com (Mark Sims) Date: Thu, 28 Aug 2008 18:27:28 +0000 Subject: [time-nuts] E-5680A C-field trimer ?? In-Reply-To: References: Message-ID: Reposted with a proper title: I am only really familiar with the 5650A/5680A with the AD9830A DDS chip that responds to the ASCII "S/E/F" commands. This manual talks about a 5680A with a different set of commands: http://tonga.globat.com/~ko4bb.com/Manuals/5)_GPS_Timing/FE5680A_Opt2_TechManRevised.doc Hopefully it will let you talk to your unit... ---------------------------------------- Mark, which pot is it ? Rex and myself bought units that were not programmable. Both of us have tweaked the pots and have not seen any change in drift. I turned pots 1 turn per day and did phase observations, over the course of a week. They guy that sold these units on ebay claimed they were programmable but could not produce the information. Its been noted he has changed his ebay user name about every 6 months (that might give you an idea about his operation - he also complained about whiny time-nuts postings about his operation). _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From GandalfG8 at aol.com Thu Aug 28 14:41:06 2008 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Thu, 28 Aug 2008 14:41:06 EDT Subject: [time-nuts] PTS Meter Message-ID: In a message dated 28/08/2008 18:12:45 GMT Daylight Time, had at to-way.com writes: Just picked up a PTS-160 that seems to be working fine except for the front panel meter. Appears to have either an open coil or a open connection at a pivot point. No DC continuity through the meter. Anybody have a dead synthesizer that might entertain a deal on the meter? ------------------ Hi Had Sorry I can't help with the meter, even if I had one a dead PTS160 would still be much too nice to break up:-) I did look in the manual, hoping to find a meter spec for you in case something else would fit, but it seems to be one of those odd parts that isn't listed with the PCB components but not with the panel components either. I'm sure a little experimentation could find something suitable but even when working the meter isn't very precise so you could probably do just as well by marking around the level control. That's what's done on most, if not all, versions of the Wavetek 5120A which is their equivalent of the PTS160. Did you get a manual with your PTS160? regards Nigel GM8PZR From stijena at tapko.de Thu Aug 28 19:04:41 2008 From: stijena at tapko.de (Predrag Dukic) Date: Fri, 29 Aug 2008 01:04:41 +0200 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: References: Message-ID: <7.0.1.0.0.20080829010253.01dce778@tapko.de> I also had the same feeling until I changed the position of the antenna from eastern side of the building to the southern. At least two usable svs more on the average... P. Dukic At 19:05 28.8.2008, you wrote: >The Thunderbolt does not seem to be the most sensitive receiver >around, but it does not seem particularly bad. Sensitivity in a >time receiver can be a bad thing... more sensitivity tends to make >it more susceptible to multipath, etc. These things were meant to >be mounted on cell towers, etc where they have a pretty clear view >of the sky. Once you have that, you don't need high >sensitivity. Also their proximity to high power RF transmitters >makes overly sensitive front ends a problem. > >On the subject of GPS amplifiers... adding external amplification >to a GPS may not improve its performance and can actually degrade >it. All amplifiers amplify signal and noise, plus distort >everything in the process. (fundamental laws of the universe: 1) You >can't get something for nothing, 2) You can't break even, 3) >You'll die trying) Ideally, you want the amplifier at the >antenna and you want the amplification to match the cable loss and >no more. Generally GPS receivers with poor sensitivity have poorly >designed front ends or signal processing. Yelling in their ears >won't make them work any better. >---------------------------------------- > >_________________________________________________________________ >Get ideas on sharing photos from people like you. Find new ways to share. >http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 >_______________________________________________ >time-nuts mailing list -- 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 smace at intt.net Thu Aug 28 19:11:23 2008 From: smace at intt.net (Scott Mace) Date: Thu, 28 Aug 2008 18:11:23 -0500 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: References: Message-ID: <48B7309B.5000209@intt.net> Both of the thunderbolts I have usually see 7-8 satellites, SNRs from 35-50, antenna is on the roof with about 150ft of LMR-400 and going through 2 4-port distribution splitter/amps. I use the belden equiv of LMR-195 for all connections between the receivers and the amps. Both thunderbolts seem to compare well to the M12+ based Fury, and do usually better than the 6-channel VP z3801a. Scott Mark Sims wrote: > The Thunderbolt does not seem to be the most sensitive receiver around, but it does not seem particularly bad. Sensitivity in a time receiver can be a bad thing... more sensitivity tends to make it more susceptible to multipath, etc. These things were meant to be mounted on cell towers, etc where they have a pretty clear view of the sky. Once you have that, you don't need high sensitivity. Also their proximity to high power RF transmitters makes overly sensitive front ends a problem. > > On the subject of GPS amplifiers... adding external amplification to a GPS may not improve its performance and can actually degrade it. All amplifiers amplify signal and noise, plus distort everything in the process. (fundamental laws of the universe: 1) You can't get something for nothing, 2) You can't break even, 3) You'll die trying) Ideally, you want the amplifier at the antenna and you want the amplification to match the cable loss and no more. Generally GPS receivers with poor sensitivity have poorly designed front ends or signal processing. Yelling in their ears won't make them work any better. > ---------------------------------------- > > _________________________________________________________________ > Get ideas on sharing photos from people like you. Find new ways to share. > http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 > _______________________________________________ > time-nuts mailing list -- 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 masondg44 at comcast.net Thu Aug 28 19:55:57 2008 From: masondg44 at comcast.net (Dave M) Date: Thu, 28 Aug 2008 19:55:57 -0400 Subject: [time-nuts] Re Phil's Fluke Monotronics equipment Message-ID: <021EAADBA867423193786E7F12C5812E@DELL2350> Phil, I'm a new subscriber to this forum. I saw that you have a manual for the Montronics 103A comparator. I have one of these and could use a manual for it. It's a bit flaky with a standard freq of 3 MHz in that the phase meter wanders a *LOT* more than it should when compared with a 1 MHz reference. Have you scanned the manual yet? I also have a Montronics 102 comparator that I don't need. Don't know if it works or not.. I acquired it a couple years ago with a lot of other stuff... just haven't bothered to check it out. Does anyone have a manual for the model 102? I'd be interested in getting a copy. I'd like to check it out, fix it if necessary and sell to somebody who needs it. -- Dave M MasonDG44 at comcast dot net (Just substitute the appropriate characters in the address) Life is like a roll of toilet paper; the closer it gets to the end, the faster it goes. >Bill, >Just looked and it's Fluke/Montronics model 103A >It's a big manual if I recall, about the same size as the 207. I could scan >it later but need some block of time on that one. >If you "need" it, I could perhaps drop it off at a copy shop and let them >duplicate it. Most of those manuals had large pull-out schematics. > >Phil From wb6bnq at cox.net Thu Aug 28 20:41:02 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Thu, 28 Aug 2008 17:41:02 -0700 Subject: [time-nuts] Re Phil's Fluke Monotronics equipment References: <021EAADBA867423193786E7F12C5812E@DELL2350> Message-ID: <48B7459E.320B6AF0@cox.net> Dave and Phil, I have one of those comparators as well. Mine is marked "FLUKE Montronics" model 100 ser # 196. It has vertical, horizontal quadrature outputs and a delta F output. The range of measurement is from 10^-6 to 10^-9. This one works as far as I can tell but, unfortunately, I have not found a manual or even a reference to it anywhere on the WEB or at surplkus places offering books. Bill....WB6BNQ Dave M wrote: > Phil, > I'm a new subscriber to this forum. I saw that you have a manual for the Montronics 103A comparator. I have one of these and could use a manual for it. It's a bit flaky with a standard freq of 3 MHz in that the phase meter wanders a *LOT* more than it should when compared with a 1 MHz reference. Have you scanned the manual yet? > > I also have a Montronics 102 comparator that I don't need. Don't know if it works or not.. I acquired it a couple years ago with a lot of other stuff... just haven't bothered to check it out. Does anyone have a manual for the model 102? I'd be interested in getting a copy. I'd like to check it out, fix it if necessary and sell to somebody who needs it. > > -- > Dave M > MasonDG44 at comcast dot net (Just substitute the appropriate characters in the address) > > Life is like a roll of toilet paper; the closer it gets to the end, the faster it goes. > > >Bill, > >Just looked and it's Fluke/Montronics model 103A > >It's a big manual if I recall, about the same size as the 207. I could scan > >it later but need some block of time on that one. > >If you "need" it, I could perhaps drop it off at a copy shop and let them > >duplicate it. Most of those manuals had large pull-out schematics. > > > >Phil > > _______________________________________________ > time-nuts mailing list -- 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 kirbybq at bellsouth.net Thu Aug 28 21:37:12 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Thu, 28 Aug 2008 20:37:12 -0500 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: References: Message-ID: <48B752C8.3080206@bellsouth.net> My problem is I am using a Motorola antenna with 24 db of gain, looking at Trimble they expect 35 db gain. I am in an apartment and the management let me put up a GPS antenna on the edge of the roof. I came down with 20 feet of RG6 and then jumped into RG59 coax to run inside the apartment. I "guesstimate" there is 40 to 60 feet in the RG59 run. I added a cheap DSS amplifier at the GPS splitters and its improved. I am going to look into moving the amp to where the coax comes into the building , the RG6/RG59 junction - but I will need to figure out a bias tee scheme to feed 12 volts to the DSS amp, and then I need to take it out and bias the antenna at +5 volts. Brian - KD4FM Mark Sims wrote: > The Thunderbolt does not seem to be the most sensitive receiver around, but it does not seem particularly bad. Sensitivity in a time receiver can be a bad thing... more sensitivity tends to make it more susceptible to multipath, etc. These things were meant to be mounted on cell towers, etc where they have a pretty clear view of the sky. Once you have that, you don't need high sensitivity. Also their proximity to high power RF transmitters makes overly sensitive front ends a problem. > > On the subject of GPS amplifiers... adding external amplification to a GPS may not improve its performance and can actually degrade it. All amplifiers amplify signal and noise, plus distort everything in the process. (fundamental laws of the universe: 1) You can't get something for nothing, 2) You can't break even, 3) You'll die trying) Ideally, you want the amplifier at the antenna and you want the amplification to match the cable loss and no more. Generally GPS receivers with poor sensitivity have poorly designed front ends or signal processing. Yelling in their ears won't make them work any better. > ---------------------------------------- > > _________________________________________________________________ > Get ideas on sharing photos from people like you. Find new ways to share. > http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_Gallery_082008 > _______________________________________________ > time-nuts mailing list -- 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 Thu Aug 28 22:39:09 2008 From: jltran at worldnet.att.net (J. L. Trantham) Date: Thu, 28 Aug 2008 21:39:09 -0500 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: <7.0.1.0.0.20080829010253.01dce778@tapko.de> Message-ID: <2B8E0D75401B4233A1794207644D5004@S0028384766> When I compared the function of the Thunderbolt to my Z3816A, the number of tracked satellites was smaller on the Thunderbolt. However, the Signal Level Mask is set to 4.0 on the Thunderbolt. After I reset it to 1.0, they tracked the same (and number of) satellites. This I did with TBoltMon under 'Setup', 'GPS Receiver' which takes you to 'Receiver Configuration'. Change the Signal Level Mask (AMU) to the desired number then 'Set Receiver'. I also hit 'Save Segment' though I do not know if this is a required step. Joe -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Predrag Dukic Sent: Thursday, August 28, 2008 6:05 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Trimble Thunderbolt - Receive Sensistivity I also had the same feeling until I changed the position of the antenna from eastern side of the building to the southern. At least two usable svs more on the average... P. Dukic At 19:05 28.8.2008, you wrote: >The Thunderbolt does not seem to be the most sensitive receiver >around, but it does not seem particularly bad. Sensitivity in a >time receiver can be a bad thing... more sensitivity tends to make >it more susceptible to multipath, etc. These things were meant to >be mounted on cell towers, etc where they have a pretty clear view >of the sky. Once you have that, you don't need high >sensitivity. Also their proximity to high power RF transmitters >makes overly sensitive front ends a problem. > >On the subject of GPS amplifiers... adding external amplification >to a GPS may not improve its performance and can actually degrade >it. All amplifiers amplify signal and noise, plus distort >everything in the process. (fundamental laws of the universe: 1) You >can't get something for nothing, 2) You can't break even, 3) >You'll die trying) Ideally, you want the amplifier at the >antenna and you want the amplification to match the cable loss and >no more. Generally GPS receivers with poor sensitivity have poorly >designed front ends or signal processing. Yelling in their ears >won't make them work any better. >---------------------------------------- > >_________________________________________________________________ >Get ideas on sharing photos from people like you. Find new ways to share. >http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Pho to_Gallery_082008 >_______________________________________________ >time-nuts mailing list -- 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 Thu Aug 28 22:48:54 2008 From: jmiles at pop.net (John Miles) Date: Thu, 28 Aug 2008 19:48:54 -0700 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: <2B8E0D75401B4233A1794207644D5004@S0028384766> Message-ID: The elevation mask might also come into play. Ordinarily you don't want to consider input from satellites too near the horizon, as terrestrial features can distort the signal's timing. I think it can be stated with confidence that there's nothing wrong with a (normally functioning) Thunderbolt's sensitivity specs, and that putting random amplifiers, splitters, and such into the antenna lead might be counterproductive. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of J. L. Trantham > Sent: Thursday, August 28, 2008 7:39 PM > To: 'Discussion of precise time and frequency measurement' > Subject: Re: [time-nuts] Trimble Thunderbolt - Receive Sensistivity > > > When I compared the function of the Thunderbolt to my Z3816A, the > number of > tracked satellites was smaller on the Thunderbolt. However, the Signal > Level Mask is set to 4.0 on the Thunderbolt. After I reset it to > 1.0, they > tracked the same (and number of) satellites. > > This I did with TBoltMon under 'Setup', 'GPS Receiver' which takes you to > 'Receiver Configuration'. Change the Signal Level Mask (AMU) to > the desired > number then 'Set Receiver'. I also hit 'Save Segment' though I > do not know > if this is a required step. > > Joe From jltran at worldnet.att.net Thu Aug 28 23:39:22 2008 From: jltran at worldnet.att.net (J. L. Trantham) Date: Thu, 28 Aug 2008 22:39:22 -0500 Subject: [time-nuts] Trimble Thunderbolt - Receive Sensistivity In-Reply-To: Message-ID: <0643D6FD4D8642BFB7CEA03016F38F54@S0028384766> You are correct about the elevation mask and it, too, can be changed via TBoltMon. However, the Thunderbolt and the Z3816A both had the elevation mask set to 10 degrees. They were running off the same HP timing antenna with 25 feet of RG-58 to a 58536A Symmetricom GPS distribution amplifier and then a short RG-58 jumper to the respective receivers with N to BNC adapters everywhere and BNC connectors on the RG-58. Clearly not the most ideal cable system but it works for comparison. Joe -----Original Message----- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of John Miles Sent: Thursday, August 28, 2008 9:49 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Trimble Thunderbolt - Receive Sensistivity The elevation mask might also come into play. Ordinarily you don't want to consider input from satellites too near the horizon, as terrestrial features can distort the signal's timing. I think it can be stated with confidence that there's nothing wrong with a (normally functioning) Thunderbolt's sensitivity specs, and that putting random amplifiers, splitters, and such into the antenna lead might be counterproductive. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On > Behalf Of J. L. Trantham > Sent: Thursday, August 28, 2008 7:39 PM > To: 'Discussion of precise time and frequency measurement' > Subject: Re: [time-nuts] Trimble Thunderbolt - Receive Sensistivity > > > When I compared the function of the Thunderbolt to my Z3816A, the > number of > tracked satellites was smaller on the Thunderbolt. However, the Signal > Level Mask is set to 4.0 on the Thunderbolt. After I reset it to > 1.0, they > tracked the same (and number of) satellites. > > This I did with TBoltMon under 'Setup', 'GPS Receiver' which takes you to > 'Receiver Configuration'. Change the Signal Level Mask (AMU) to > the desired > number then 'Set Receiver'. I also hit 'Save Segment' though I > do not know > if this is a required step. > > Joe _______________________________________________ time-nuts mailing list -- 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 scmcgrath at gmail.com Fri Aug 29 10:25:09 2008 From: scmcgrath at gmail.com (Scott McGrath) Date: Fri, 29 Aug 2008 10:25:09 -0400 Subject: [time-nuts] Manual Request for 5065A prefix 1840A Message-ID: Hi, Need a manual for a 5065A Prefix 1840A Rb frequency standard - I have the preliminary manual but this does not cover the late version with digital clock. I am in the process of digitizing the preliminary manual and will make it available will probably upload to ko4bb's manual site as well so as to spread the information wider. Thanks - Scott From cfharris at erols.com Fri Aug 29 10:58:30 2008 From: cfharris at erols.com (Chuck Harris) Date: Fri, 29 Aug 2008 10:58:30 -0400 Subject: [time-nuts] Manual Request for 5065A prefix 1840A In-Reply-To: References: Message-ID: <48B80E96.7030802@erols.com> Hi Scott, I have the last manual made, it was prefix 1908A, and there are yellow sheets up to 2816A. My copy was bought directly from HP, in the late 1980's(IIRC). -Chuck Harris Scott McGrath wrote: > Hi, > > Need a manual for a 5065A Prefix 1840A Rb frequency standard - > > I have the preliminary manual but this does not cover the late version > with digital clock. I am in the process of digitizing the > preliminary manual and will make it available will probably upload to > ko4bb's manual site as well so as to spread the information wider. > > Thanks - Scott > > _______________________________________________ > time-nuts mailing list -- 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 Fri Aug 29 12:39:47 2008 From: cdelect at juno.com (corby d dawson) Date: Fri, 29 Aug 2008 09:39:47 -0700 Subject: [time-nuts] HP 5065A manual Message-ID: <20080829.093948.-762701.0.cdelect@juno.com> Chuck, Could I get a copy of the yellow sheets change pages? Thanks! Corby Dawson ____________________________________________________________ Click here for great computer networking solutions! http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3oHgMkL3IcgFXlOqPKqH7UVm3UfxWxo6O7LbIpL7WwA1ILo1/ From jmiles at pop.net Fri Aug 29 14:41:06 2008 From: jmiles at pop.net (John Miles) Date: Fri, 29 Aug 2008 11:41:06 -0700 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: <48B5E154.7020905@quackers.net> Message-ID: I'm not familiar with any GPIB bugs on the 5370A, but I moved your code over to C and ran it on my 5370B via a GPIB-LAN adapter. The test app failed after ~6 hours with a Winsock timeout error. I'm thinking that was caused by a power glitch, though, because I actually had to power-cycle the counter (rather than the Prologix dongle) to get the program running again. Was that your experience? Since then it's finished a 24-hour run without any sign of trouble. -- john, KE5FX > If the 5370A problem is actually the 5370A gpib controller bug, then I > don't think it can be reproduced with the 5370B; I'm pretty sure that > was fixed in the B model. > However, if you want to give it a try, here's what I do (you'll have to > interpret, but it should be pretty clear)... C version: GPIB_connect(atoi(argv[1]), GPIB_error, 0, 20000); // Set 20-second timeout GPIB_set_EOS_mode(10); GPIB_set_serial_read_dropout(20000); // 20-second dropout GPIB_write("SS2"); // Sample size = 100 GPIB_write("MD2"); // Lock out rate control, hold until MR GPIB_write("AR1"); // +T.I. arming only Sleep(2000); GPIB_write("MR"); // Manual read (discard first reading) Sleep(1000); for (S32 h=0; h < 24; h++) { for (S32 m=0; m < 60; m++) { for (S32 s=0; s < 60; s++) { GPIB_write("MR"); Sleep(1000); printf("%d:%d:%d %s", h,m,s, GPIB_read_ASC()); } } } From wje at quackers.net Fri Aug 29 15:30:34 2008 From: wje at quackers.net (wje) Date: Fri, 29 Aug 2008 15:30:34 -0400 Subject: [time-nuts] Prologix GPIB-NET, HP 5370A, HP5334A problem? In-Reply-To: References: Message-ID: <48B84E5A.90800@quackers.net> Yes, that was essentially what I was seeing over a few runs. The failure times I saw were on the order of 2-4 hours. I've moved my 5370 over to a UPS, along with the Prologix and the router, and I'll see what happens. I have to wait until my 3-day 5334 run finishes, though. I'm measuring long-term phase difference between my 5061A and my Z3801A. The 5334 has been running solidly for 1.5 days, so I can eliminate power problems at this point. This brings up another question. I'm seeing cyclic phase variations of about 10 ns with a pretty regular 1 hour cycle. The overall long-term average is OK, 1e-13 ADEV at 6000 seconds. I'm guessing this has something to do with satellite orbits, but I'd welcome any explanations. As for the 5370A bug, there was a thread a while back in time-nuts describing a bug in the GPIB controllers for the 5370A's that would occasionally and randomly cause a bus lockup. This problem was supposedly fixed in the B series. That's all I've seen on the issue, so it's possible that the bug doesn't actually exist. If I still get failures, I'll swap in a controller from my spare 5370 and see if there's any difference. BTW, I've been doing precision AC and DC measurements for a long time, but I have to say that high-resolution time/freq measurements are even more fun! Bill Ezell ---------- They said 'Windows or better' so I used Linux. John Miles wrote: I'm not familiar with any GPIB bugs on the 5370A, but I moved your code over to C and ran it on my 5370B via a GPIB-LAN adapter. The test app failed after ~6 hours with a Winsock timeout error. I'm thinking that was caused by a power glitch, though, because I actually had to power-cycle the counter (rather than the Prologix dongle) to get the program running again. Was that your experience? Since then it's finished a 24-hour run without any sign of trouble. -- john, KE5FX If the 5370A problem is actually the 5370A gpib controller bug, then I don't think it can be reproduced with the 5370B; I'm pretty sure that was fixed in the B model. However, if you want to give it a try, here's what I do (you'll have to interpret, but it should be pretty clear)... C version: GPIB_connect(atoi(argv[1]), GPIB_error, 0, 20000); // Set 20-second timeout GPIB_set_EOS_mode(10); GPIB_set_serial_read_dropout(20000); // 20-second dropout GPIB_write("SS2"); // Sample size = 100 GPIB_write("MD2"); // Lock out rate control, hold until MR GPIB_write("AR1"); // +T.I. arming only Sleep(2000); GPIB_write("MR"); // Manual read (discard first reading) Sleep(1000); for (S32 h=0; h < 24; h++) { for (S32 m=0; m < 60; m++) { for (S32 s=0; s < 60; s++) { GPIB_write("MR"); Sleep(1000); printf("%d:%d:%d %s", h,m,s, GPIB_read_ASC()); } } } _______________________________________________ time-nuts mailing list -- [1]time-nuts at febo.com To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts at febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From wb6bnq at cox.net Fri Aug 29 17:37:28 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Fri, 29 Aug 2008 14:37:28 -0700 Subject: [time-nuts] Chinese Time Station References: Message-ID: <48B86C18.E7EB3831@cox.net> Hello to All, I live in San Diego, California, USA and normally do not get to bed until around 3 to 3:30pm. I have an Amateur radio transceiver next to my bed and often listen to Amateur conversations while falling asleep. Besides my favorite listening spots, I, of course, have the WWV time channels programmed into memory. My experience with WWV is 15 and 10 MHz is good during the day while 5 and 2.5 MHz do well at night with 5 MHz usually being the best. Sometimes I hear 10 MHz but it is usually quite weak or nonexistent. Until today I have never heard another time station on 10 MHz. Early this morning, Friday, August 29, 2008, for the first time ever, I heard another country?s time station besides WWV on the standard frequencies. I happened to flip to the WWV 10 MHz memory and heard what sounded like local computer data spurts. Thinking it could be the time rack in the back room or it could be the cable modem or router, I decided to keep listening. A CW ID, repeated about twenty times, came next after which a voice announcement followed by a tone at the bottom of the hour. What continued was a one second pulse just like WWV. However, this one second pulse sounded more like a ?TICK? sound of a narrower pulse. The US pulse sounds more like a ?TOCK? sound. So I listened for a one minute announcement. Oops, no 1, 5, 10 or 15 minute announcements. Finally, thirty minutes later (4:00am) it again went through computer sequence, ID, voice and tone. From bill at iaxs.net Fri Aug 29 18:43:32 2008 From: bill at iaxs.net (Bill Hawkins) Date: Fri, 29 Aug 2008 17:43:32 -0500 Subject: [time-nuts] Chinese Time Station In-Reply-To: <48B86C18.E7EB3831@cox.net> References: <48B86C18.E7EB3831@cox.net> Message-ID: <000c01c90a28$aa819b40$021ba8c0@cyrus> I wonder why you didn't mention WWVH in Hawaii. Same frequencies as WWV, same schedule, but the voice is female. Heard it here in Minnesota several years ago on a Lavoie time receiver with vacuum tubes. The set had a 2" CRT drawing a circular trace at 10 MHz and intensity modulated with the carrier signal. Normally half the circle is bright. When WWV and WWVH alternated, the bright half shifted about 180 degrees. Bill Hawkins From wb6bnq at cox.net Fri Aug 29 19:45:23 2008 From: wb6bnq at cox.net (WB6BNQ) Date: Fri, 29 Aug 2008 16:45:23 -0700 Subject: [time-nuts] Chinese Time Station References: <48B86C18.E7EB3831@cox.net> <000c01c90a28$aa819b40$021ba8c0@cyrus> Message-ID: <48B88A13.9F416075@cox.net> Hi Bill, You're right there are two US stations on the HF band, WWV and WWVH. I was generically referring to them both. Although in my mind I did not really think of WWVH per se. In either case neither WWV or WWVH were not there in any recognizable strength. Bill....WB6BNQ Bill Hawkins wrote: > I wonder why you didn't mention WWVH in Hawaii. Same frequencies as WWV, > same schedule, but the voice is female. Heard it here in Minnesota > several > years ago on a Lavoie time receiver with vacuum tubes. The set had a 2" > CRT drawing a circular trace at 10 MHz and intensity modulated with the > carrier signal. Normally half the circle is bright. When WWV and WWVH > alternated, the bright half shifted about 180 degrees. > > Bill Hawkins > > _______________________________________________ > time-nuts mailing list -- 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 Fri Aug 29 20:09:44 2008 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Fri, 29 Aug 2008 20:09:44 EDT Subject: [time-nuts] PTS160 Manual Message-ID: Hi All I uploaded the manual for the Programmed Test Sources PTS160 Frequency Synthesiser to Didier's site earlier today, so it should be available for download soon. Regards Nigel GM8PZR From pieter.ibelings at gmail.com Fri Aug 29 22:21:43 2008 From: pieter.ibelings at gmail.com (Pieter Ibelings) Date: Fri, 29 Aug 2008 22:21:43 -0400 Subject: [time-nuts] Trimble Thunderbolt 1PPS TTL level? References: Message-ID: <739F0DE2F9294033AB51D2662F023180@xps> Hi All, I got a Trimble Thunderbold from Ebay and I am having trouble triggering the HP 53131A. The 1PPS output shows a 10us pulse of 1 Volt into a high impedance probe. This seems low to me. Should it be 5 volts? Maybe the output 74AC04 is toast? Pieter, N4IP From smace at intt.net Fri Aug 29 22:38:06 2008 From: smace at intt.net (Scott Mace) Date: Fri, 29 Aug 2008 21:38:06 -0500 Subject: [time-nuts] Trimble Thunderbolt 1PPS TTL level? In-Reply-To: <739F0DE2F9294033AB51D2662F023180@xps> References: <739F0DE2F9294033AB51D2662F023180@xps> Message-ID: <48B8B28E.40807@intt.net> Have you tried terminating it with 50ohms? That was the trick for mine. Scott Pieter Ibelings wrote: > Hi All, > > I got a Trimble Thunderbold from Ebay and I am having trouble triggering the > HP 53131A. The 1PPS output shows a 10us pulse of 1 Volt into a high > impedance probe. This seems low to me. Should it be 5 volts? Maybe the > output 74AC04 is toast? > > 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 d.seiter at comcast.net Sat Aug 30 02:17:46 2008 From: d.seiter at comcast.net (d.seiter at comcast.net) Date: Sat, 30 Aug 2008 06:17:46 +0000 Subject: [time-nuts] OT- R&K devices? Message-ID: <083020080617.11381.48B8E60A000BBF4F00002C7522069997359D0A9B070A9CD20B@comcast.net> I'm drawing a blank on a blank on a pile of R&K devices I just found in a few boxes I had forgotten about. They look like relays or filters (2x4 pin, non-hermetic metal case, 10x10x20mm), internally it looks like an active device with a balun on both sides under silicone. I remember R&K, but I can't find any info on the web. I have about 70 of them in different flavors. Any leads? -Dave From jpawlan at pawlan.com Sat Aug 30 02:20:10 2008 From: jpawlan at pawlan.com (Jeffrey Pawlan) Date: Fri, 29 Aug 2008 23:20:10 -0700 (PDT) Subject: [time-nuts] OT- R&K devices? In-Reply-To: <083020080617.11381.48B8E60A000BBF4F00002C7522069997359D0A9B070A9CD20B@comcast.net> Message-ID: They were a competitor to minicircuits and others. Tried to win by being very inexpensive. From d.seiter at comcast.net Sat Aug 30 03:41:21 2008 From: d.seiter at comcast.net (d.seiter at comcast.net) Date: Sat, 30 Aug 2008 07:41:21 +0000 Subject: [time-nuts] OT- R&K devices? Message-ID: <083020080741.6858.48B8F9A10009623800001ACA22007340769D0A9B070A9CD20B@comcast.net> The parts I have don't have date codes, but they must be circa 1990. Is there any data out there regarding R&K devices? My library has nothing and the web appears to be silent too. -------------- Original message ---------------------- From: Jeffrey Pawlan > They were a competitor to minicircuits and others. Tried to win by being very > inexpensive. > > > > > > _______________________________________________ > time-nuts mailing list -- 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 mpb45 at clanbaker.org Sat Aug 30 04:30:53 2008 From: mpb45 at clanbaker.org (Michael Baker) Date: Sat, 30 Aug 2008 04:30:53 -0400 Subject: [time-nuts] Thunderbolt self-survey results... Message-ID: <48B9053D.40607@clanbaker.org> Hello, All-- My Thunderbolt seems to be able to determine its Lat and Lon location coordinates with reasonable accuracy. However, after completing its self-survey it thinks its elevation is 11.2 meters when the actual elevation of its antenna (on my house roof) is 28.4 meters. I arrived at this value by looking at the USGS topo map of my property, noting the elevation ABMSL where my house is located and adding the distance from the ground to the GPS antenna on my roof and coming up with 28.4 meters. Should I store this value into POSITION/ALTITUDE? If I enter this value into ALTITUDE, then what? Should I then SAVE SEGMENT? SET ACCURATE POSITION? Thanks, Mike Baker WA4HFR Micanopy, FL From dave.g0dja at tiscali.co.uk Sat Aug 30 06:09:36 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sat, 30 Aug 2008 11:09:36 +0100 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: <48B9053D.40607@clanbaker.org> References: <48B9053D.40607@clanbaker.org> Message-ID: <48B91C60.3070705@tiscali.co.uk> Michael Baker wrote: > However, after completing its self-survey it thinks > its elevation is 11.2 meters when the actual elevation > of its antenna (on my house roof) is 28.4 meters. I've not found any GPS receiver, available to the general pubic anyway, that correctly reports its height above sea level. So, I tend to ignore that reading, personally. Dave (G0DJA) From jpradoes at telefonica.net Sat Aug 30 06:30:13 2008 From: jpradoes at telefonica.net (Jose Manuel) Date: Sat, 30 Aug 2008 12:30:13 +0200 Subject: [time-nuts] Thunderbolt self-survey results... References: <48B9053D.40607@clanbaker.org> Message-ID: <000901c90a8b$63d316c0$2201a8c0@PC2> Hello Mike and Group, The altitude shown by Th is the WGS84 ellipsoidal altitude, so if you wish to know your MSL, or ortometric altitude, it?s necessary to take into account the undulation or difference between the geoid and the WGS84 ellipsoid for your location. You can see a wordwide map for such differences: http://www.colorado.edu/geography/gcraft/notes/datum/gif/geoid2.gif Hope this helps......Jos?, EA1PX ----- Original Message ----- From: "Michael Baker" To: Sent: Saturday, August 30, 2008 10:30 AM Subject: [time-nuts] Thunderbolt self-survey results... > Hello, All-- > > My Thunderbolt seems to be able to determine its > Lat and Lon location coordinates with reasonable accuracy. > > However, after completing its self-survey it thinks > its elevation is 11.2 meters when the actual elevation > of its antenna (on my house roof) is 28.4 meters. > > I arrived at this value by looking at the USGS topo > map of my property, noting the elevation ABMSL where > my house is located and adding the distance from > the ground to the GPS antenna on my roof and coming up > with 28.4 meters. > > Should I store this value into POSITION/ALTITUDE? > > If I enter this value into ALTITUDE, then what? > Should I then SAVE SEGMENT? SET ACCURATE POSITION? > > Thanks, > > Mike Baker > WA4HFR > Micanopy, FL > > > > _______________________________________________ > time-nuts mailing list -- 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. > Version: 7.5.526 / Virus Database: 270.6.13/1641 - Release Date: > 29/08/2008 7:07 > > From dave.g0dja at tiscali.co.uk Sat Aug 30 06:48:16 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sat, 30 Aug 2008 11:48:16 +0100 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: <000901c90a8b$63d316c0$2201a8c0@PC2> References: <48B9053D.40607@clanbaker.org> <000901c90a8b$63d316c0$2201a8c0@PC2> Message-ID: <48B92570.2090806@tiscali.co.uk> There's a discussion of the different height measurements and the errors found when using 4 Garmin GPS receivers at http://users.erols.com/dlwilson/gpsvert.htm From bg at lysator.liu.se Sat Aug 30 09:42:35 2008 From: bg at lysator.liu.se (=?ISO-8859-1?Q?Bj=F6rn?= Gabrielsson) Date: Sat, 30 Aug 2008 15:42:35 +0200 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: <48B91C60.3070705@tiscali.co.uk> References: <48B9053D.40607@clanbaker.org> <48B91C60.3070705@tiscali.co.uk> Message-ID: <1220103755.5824.32.camel@bg-desktop> Hi Dave, On Sat, 2008-08-30 at 11:09 +0100, David Ackrill wrote: > Michael Baker wrote: > > > However, after completing its self-survey it thinks > > its elevation is 11.2 meters when the actual elevation > > of its antenna (on my house roof) is 28.4 meters. > > I've not found any GPS receiver, available to the general pubic anyway, > that correctly reports its height above sea level. So, I tend to ignore > that reading, personally. Due to geometric reasons the GPS altitude/height-accuracy is worse by a factor ca 1.8, than the horizontal (2d) accuracy. This gives the basic reason the vertical is worse. Other factors contributing - the earth is flat (!?) ie heights from maps of sea levels etc can be very accurate. - user confusion of ellipsoid height (that GPS works in) and geoid height (mean sea level height). You need to know/check which height is given by the GPS in each "message" you are looking. - inaccurate geoid model in the GPS to translate ellipsoid height to Geoid height. - modern high sensitivity receivers will happily track signals that have bounced a couple times between floor and ceiling, which of cause gives even worse height accuracy. > Dave (G0DJA) -- Bj?rn From Arnold.Tibus at gmx.de Sat Aug 30 10:12:23 2008 From: Arnold.Tibus at gmx.de (Arnold Tibus) Date: Sat, 30 Aug 2008 16:12:23 +0200 Subject: [time-nuts] Trimble Thunderbolt 1PPS TTL level? In-Reply-To: <739F0DE2F9294033AB51D2662F023180@xps> Message-ID: On Fri, 29 Aug 2008 22:21:43 -0400, Pieter Ibelings wrote: >Hi All, >I got a Trimble Thunderbold from Ebay and I am having trouble triggering the >HP 53131A. The 1PPS output shows a 10us pulse of 1 Volt into a high >impedance probe. This seems low to me. Should it be 5 volts? Maybe the >output 74AC04 is toast? >Pieter, N4IP Hi Pieter, there is nothing to be worried about, I have the same problem with my 53132A, it does not trigger on it with 50 ohms or high impedance load. So I tried it with the 5334A - no problem at all ! It does trigger as expected, without any signal loss. Seem to be a problem of the 53131A/ 53132A series counter. regards, Arnold From pieter.ibelings at gmail.com Sat Aug 30 10:29:15 2008 From: pieter.ibelings at gmail.com (Pieter Ibelings) Date: Sat, 30 Aug 2008 10:29:15 -0400 Subject: [time-nuts] Trimble Thunderbolt 1PPS TTL level? References: Message-ID: Arnold, Thanks. I had a dirty BNC connector so I am now getting 5 volts and 10us wide. I cannot get the counter to lock. There has to be a way of getting it to work. Regards, Pieter ----- Original Message ----- From: "Arnold Tibus" To: "Discussion of precise time and frequency measurement" Sent: Saturday, August 30, 2008 10:12 AM Subject: Re: [time-nuts] Trimble Thunderbolt 1PPS TTL level? > On Fri, 29 Aug 2008 22:21:43 -0400, Pieter Ibelings wrote: > >>Hi All, > >>I got a Trimble Thunderbold from Ebay and I am having trouble triggering >>the >>HP 53131A. The 1PPS output shows a 10us pulse of 1 Volt into a high >>impedance probe. This seems low to me. Should it be 5 volts? Maybe the >>output 74AC04 is toast? > >>Pieter, N4IP > > Hi Pieter, > there is nothing to be worried about, I have the same problem with my > 53132A, it does not trigger on it with 50 ohms or high impedance load. > So I tried it with the 5334A - no problem at all ! It does trigger as > expected, > without any signal loss. > Seem to be a problem of the 53131A/ 53132A series counter. > > regards, > Arnold > > > > _______________________________________________ > time-nuts mailing list -- 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 Sat Aug 30 10:32:50 2008 From: bg at lysator.liu.se (=?ISO-8859-1?Q?Bj=F6rn?= Gabrielsson) Date: Sat, 30 Aug 2008 16:32:50 +0200 Subject: [time-nuts] Trimble Thunderbolt 1PPS TTL level? In-Reply-To: References: Message-ID: <1220106770.5824.48.camel@bg-desktop> On Sat, 2008-08-30 at 16:12 +0200, Arnold Tibus wrote: > On Fri, 29 Aug 2008 22:21:43 -0400, Pieter Ibelings wrote: > > >Hi All, > > >I got a Trimble Thunderbold from Ebay and I am having trouble triggering the > >HP 53131A. The 1PPS output shows a 10us pulse of 1 Volt into a high > >impedance probe. This seems low to me. Should it be 5 volts? Maybe the > >output 74AC04 is toast? > > >Pieter, N4IP > > Hi Pieter, > there is nothing to be worried about, I have the same problem with my > 53132A, it does not trigger on it with 50 ohms or high impedance load. > So I tried it with the 5334A - no problem at all ! It does trigger as expected, > without any signal loss. > Seem to be a problem of the 53131A/ 53132A series counter. > > regards, > Arnold Hi all, My PM6681 (aka CNT81) on automatic trigger level, fails to identify a reasonable trigger voltage. When set manually, there is no trigger problems at all. -- Bj?rn From holrum at hotmail.com Sat Aug 30 16:15:52 2008 From: holrum at hotmail.com (Mark Sims) Date: Sat, 30 Aug 2008 20:15:52 +0000 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: References: Message-ID: Besides the wonky geoid, ionospheric delays (which tend to be poorly modeled and compensated for in single frequency receivers) tend to affect the altitude reading the most. You also need to set the cable delay time for best accuracy. Also, for a cheap thrill, run the self survey several times (preferably at the same and at different times of the day) and see how much it varies. I set my location to the centroid of about a dozen surveys done over three days. ---------------------------------------- _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From tvb at LeapSecond.com Sat Aug 30 16:26:58 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Sat, 30 Aug 2008 13:26:58 -0700 Subject: [time-nuts] Thunderbolt self-survey results... References: Message-ID: <000301c90ade$c460b760$0700a8c0@pc52> > I set my location to the centroid of about a dozen surveys done over three days. What was the standard deviation of the dozen surveys? /tvb From not.again at btinternet.com Sat Aug 30 16:36:34 2008 From: not.again at btinternet.com (Angus) Date: Sat, 30 Aug 2008 21:36:34 +0100 Subject: [time-nuts] 10811A versus 10811-60111 In-Reply-To: <227B3D52CE674F3780D0005BB79E9D1A@athlon> References: <20080826.102233.-355005.2.cdelect@juno.com> <227B3D52CE674F3780D0005BB79E9D1A@athlon> Message-ID: Old oscillators can be a bit of a pain - as the years (or decades) pass, aging and deterioration in various parts can have rather undesirable effects on the performance. Even if it does not cause actual failure, it can make them much less useful for precision applications. On Wed, 27 Aug 2008 14:43:00 +0200, you wrote: >Corby, > >the FTS specs for their FTS1000A, FTS1200, FTS1002A and FTS1003A name >short term stabilities for all four oscillators to be 1E-12 @ 1,10,100 >s. I have always believed that these specs are kind of "conservative" >ones so that your FTS1200 #2 fits them VERY well while FTS1200 #1 barely >meets the specs. > >Is there any idea on why these two oscillators behave that different? > >Best regards >Ulrich Bangert > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces at febo.com >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von corby d dawson >> Gesendet: Dienstag, 26. August 2008 19:23 >> An: time-nuts at febo.com >> Betreff: Re: [time-nuts] 10811A versus 10811-60111 >> >> >> Hi, >> >> I have had the occasion recently to measure the aging and >> short term stability of a bunch of oscillators. >> >> Measurements were against an EFOS-2 Hydrogen Maser. >> >> I thought that the results between 10811A (-60109 variant) >> and the 10811-60111 might be of interest to some. >> >> All oscillators had aging below 5X10-10/day. >> >> As you can see the short term stability of the -60111 >> compares favorably with the 10811A. >> >> I'll be making some measurements on the -60158 variants and >> some motorola units soon. >> >> Cheers! >> Corby Dawson >> >> >> QUARTZ 1 SEC. 10 SEC. 100 SEC. 1K SEC. (ALL HAD AGING BELOW >> 5X10-5/DAY) >> ------------------------------------------------ >> 10811-60109 6.11-12 2.52-12 8.78-12 >> 10811-60109 1.65-12 1.91-12 9.79-12 >> 10811-60109 1.65-12 1.99-12 1.11-12 >> 10811-60109 5.47-12 1.16-12 2.38-12 >> 105 STYLE #T 7.60-13 2.01-12 3.94-12 >> 10811-60111 1.27-12 2.65-12 1.93-12 >> 105 STYLE #2 1.14-12 1.57-12 2.26-12 >> 105 STYLE #3 1.31-12 1.58-12 2.68-12 >> 10811-60111 3.04-12 5.54-12 1.47-12 >> 105 STYLE #4 1.38-12 3.49-12 4.84-12 >> 10811-60109 2.05-12 2.89-12 3.24-12 >> 10811-60111 1.36-12 1.17-12 1.75-12 >> 105 STYLE #5 1.14-12 2.09-12 2.51-12 >> FTS 1200 #1 7.14-13 1.48-12 1.92-12 >> 10543A 2.86-11 1.05-11 1.63-11 >> FTS 1200 #2 2.99-13 4.30-13 7.69-13 8.65-13 >> 10544A 4.08-12 2.95-12 7.79-12 >> 10811-60111 1.24-12 2.10-12 2.09-12 >> 10811-60111 1.48-12 1.59-12 1.54-12 >> 10544A 1.89-12 2.99-12 5.01-12 >> 105 style #6 2.88-12 2.88-12 7.37-12 >> 105 style #7 9.69-13 2.30-12 3.49-12 >> 10544-60511 8.20-13 2.11-12 2.51-12 >> Piezo clone 2.57-12 2.23-12 2.17-12 >> 5060A osconly 4.04-12 5.94-12 8.42-12 1.30-11 >> 10811-60111 2.59-12 3.87-12 5.77-12 >> >> -60109spec 2.50-12 5.00-12 1.00-11 >> -60111spec <1.00-12 * * >> 10811Aspec 5.00-12 5.00-12 1.00-11 >> *not specified >> ____________________________________________________________ >> Click to find information on your credit score and your >> credit report. >> http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m2PczsRdNFK >t2GBl1YDtgaQ4QFPJm37HTYhIBtnzDllyvQl/ > >_______________________________________________ >time-nuts mailing list -- 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 cdelect at juno.com Sat Aug 30 17:50:43 2008 From: cdelect at juno.com (corby d dawson) Date: Sat, 30 Aug 2008 14:50:43 -0700 Subject: [time-nuts] Austron 1250B Message-ID: <20080830.145044.-516891.7.cdelect@juno.com> Hi, I am playing with an Austron 1250B and I'd like to add a fine frequency adjust. The data sheet I have on the 1150 oscillator inside indicates that the EFC input is an option. Anyone have a schematic for the 1250B that shows how the 1150 is wired in. If no EFC on this unit I'll be getting rid of it. Thanks, Corby Dawson ____________________________________________________________ Click to make millions by owning your own franchise. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m6iSRbslUuv6eYSqQX4VKjWuK9N7IRHgjWc9Dfez5DWUmBr/ From tvb at LeapSecond.com Sat Aug 30 18:22:45 2008 From: tvb at LeapSecond.com (Tom Van Baak) Date: Sat, 30 Aug 2008 15:22:45 -0700 Subject: [time-nuts] 10811A versus 10811-60111 References: <227B3D52CE674F3780D0005BB79E9D1A@athlon> Message-ID: <000f01c90aee$f067abb0$0700a8c0@pc52> > the FTS specs for their FTS1000A, FTS1200, FTS1002A and FTS1003A name > short term stabilities for all four oscillators to be 1E-12 @ 1,10,100 > s. I have always believed that these specs are kind of "conservative" > ones so that your FTS1200 #2 fits them VERY well while FTS1200 #1 barely > meets the specs. > > Is there any idea on why these two oscillators behave that different? > > Best regards > Ulrich Bangert Ulrich, I've seen this same thing for other high-end oscillators. It might boil down to the random quality of the individual quartz resonator. See for example, these dozen "identical" 10811 oscillators: http://www.leapsecond.com/pages/z3801a-osc/ This is one reason why some of us keep buying old oscillators; once in a while you run across a real gem, better than all the others before it. Some old Sulzers and some 10811 are really amazing; the same is true for many FTS 1000/1200 series. Hunting surplus stores and eBay for 1e-13 quartz is like this: http://www.old-picture.com/american-adventure/pictures/panning-Miner.jpg /tvb From GandalfG8 at aol.com Sat Aug 30 18:27:00 2008 From: GandalfG8 at aol.com (GandalfG8 at aol.com) Date: Sat, 30 Aug 2008 18:27:00 EDT Subject: [time-nuts] Austron 1250B Message-ID: In a message dated 30/08/2008 22:53:17 GMT Daylight Time, cdelect at juno.com writes: I am playing with an Austron 1250B and I'd like to add a fine frequency adjust. The data sheet I have on the 1150 oscillator inside indicates that the EFC input is an option. Anyone have a schematic for the 1250B that shows how the 1150 is wired in. If no EFC on this unit I'll be getting rid of it. ------------------------ Hi Corby I haven't got any specific information on the 1250B but did upload the manual for the 1250 to Didier's site some time ago and it's in his GPS manuals section. As far as I know both the 1250 and 1250A came with front panel fine tuning, which uses the EFC input on the oscillator, as standard. It's shown fitted in the 1250 manual and fitted to both my 1250As. I have seen photos of the 1250B without the fine frequency pot but would suspect the 1150 would be the same in all models. The 1250 manual shows little information for the 1150 itself but the overall wiring diagram shows the fine control pot being wired to pin 8 on the 1150, as well as some other connections between the 1150 and the PSU. regards Nigel GM8PZR From alan.melia at btinternet.com Sat Aug 30 18:40:48 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Sat, 30 Aug 2008 23:40:48 +0100 Subject: [time-nuts] Austron 1250B References: <20080830.145044.-516891.7.cdelect@juno.com> Message-ID: <00d001c90af1$759895e0$0900a8c0@AM> Hi Corby, my 1250a has an EFC connection on the rear panel (a bnc connector) I have some circuitry but not sure at present what "suffix" letter it refers to My 1250as have a 5MHz OCXO. Alan G3NYK ----- Original Message ----- From: "corby d dawson" To: Sent: Saturday, August 30, 2008 10:50 PM Subject: Re: [time-nuts] Austron 1250B > > Hi, > > I am playing with an Austron 1250B and I'd like to add a fine frequency > adjust. > > The data sheet I have on the 1150 oscillator inside indicates that the > EFC input is an option. > > Anyone have a schematic for the 1250B that shows how the 1150 is wired > in. > > If no EFC on this unit I'll be getting rid of it. > > Thanks, > > Corby Dawson > ____________________________________________________________ > Click to make millions by owning your own franchise. > http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m6iSRbslUuv6eYSqQX4VKjWuK 9N7IRHgjWc9Dfez5DWUmBr/ > > _______________________________________________ > time-nuts mailing list -- 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 alan.melia at btinternet.com Sat Aug 30 19:23:32 2008 From: alan.melia at btinternet.com (Alan Melia) Date: Sun, 31 Aug 2008 00:23:32 +0100 Subject: [time-nuts] Austron 1250B References: <20080830.145044.-516891.7.cdelect@juno.com> Message-ID: <00e101c90af7$70bb6920$0900a8c0@AM> Hi Corby and Nigel. I think I have a data sheet for the 1150 oscillator somewhere as well. I have an "orphan" 1MHz unit. The "a" definitely has the EFC on the rear and I recollect seeing a spec for the swing per volt. I seen to think it is quite fine and would be useful for GPS steering. Alan G3NYK ----- Original Message ----- From: "corby d dawson" To: Sent: Saturday, August 30, 2008 10:50 PM Subject: Re: [time-nuts] Austron 1250B > > Hi, > > I am playing with an Austron 1250B and I'd like to add a fine frequency > adjust. > > The data sheet I have on the 1150 oscillator inside indicates that the > EFC input is an option. > > Anyone have a schematic for the 1250B that shows how the 1150 is wired > in. > > If no EFC on this unit I'll be getting rid of it. > > Thanks, > > Corby Dawson > ____________________________________________________________ > Click to make millions by owning your own franchise. > http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m6iSRbslUuv6eYSqQX4VKjWuK 9N7IRHgjWc9Dfez5DWUmBr/ > > _______________________________________________ > time-nuts mailing list -- 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 Sat Aug 30 19:35:19 2008 From: holrum at hotmail.com (Mark Sims) Date: Sat, 30 Aug 2008 23:35:19 +0000 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: References: Message-ID: Well, I didn't start out to do a formal test of the survey repeatability. I was actually testing my ThunderBolt control program. The survey command causes lots of states in the unit to change and I was actually watching that. I did write down the results that I got each time (I think I may still have that napkin). Depending upon the time of day, a survey could complete (1200 fixes) in from under and hour to over 6 hours. Before I got my antenna in a better (but still really crappy) location, the first survey that I did took almost three days! Lat and lons were spread over around 35 feet, with most clustered within 12 feet. Altitudes were spread over 100 feet, with most clustered within 25 feet. I plotted the results, threw out the outliers (usually from those long surveys when the track satellite constellation changed every couple of seconds), and stuck a pin in the middle of what was left. Plugging the result into Google Maps was rather astonishing... the point on their photo appeared to be within inches of where the antenna is. ---------------------------------------- What was the standard deviation of the dozen surveys? _________________________________________________________________ Be the filmmaker you always wanted to be?learn how to burn a DVD with Windows?. http://clk.atdmt.com/MRT/go/108588797/direct/01/ From namichie at gmail.com Sat Aug 30 19:51:50 2008 From: namichie at gmail.com (Neville Michie) Date: Sun, 31 Aug 2008 09:51:50 +1000 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: References: Message-ID: As a microclimatologist I am very aware of the nocturnal inversions that occur in the atmosphere. From ground level to say 1000 feet the air cools at night forming a dense layer. The dielectric properties of this condition must create apparent thickness beneath the satellites. Whereas there is a balanced triangulation of northing and easting in determining lat and long that will null any atmospheric length effects, there is no way of determining the actual altitude from the apparent altitude caused by extra dielectric layering of the atmosphere and ionosphere. So there is little surprise in variable height data. What would be interesting is a correlation between apparent height error and night minimum temperature at ground level (air temperature 2 metres from the ground). cheers, Neville Michie On 31/08/2008, at 6:15 AM, Mark Sims wrote: > > Besides the wonky geoid, ionospheric delays (which tend to be > poorly modeled and compensated for in single frequency receivers) > tend to affect the altitude reading the most. > > You also need to set the cable delay time for best accuracy. > > Also, for a cheap thrill, run the self survey several times > (preferably at the same and at different times of the day) and see > how much it varies. I set my location to the centroid of about a > dozen surveys done over three days. > ---------------------------------------- > > _________________________________________________________________ > Be the filmmaker you always wanted to be?learn how to burn a DVD > with Windows?. > http://clk.atdmt.com/MRT/go/108588797/direct/01/ > _______________________________________________ > time-nuts mailing list -- 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 billj at ieee.org Sat Aug 30 19:59:49 2008 From: billj at ieee.org (Bill Janssen) Date: Sat, 30 Aug 2008 16:59:49 -0700 Subject: [time-nuts] Austron 1250B In-Reply-To: <20080830.145044.-516891.7.cdelect@juno.com> References: <20080830.145044.-516891.7.cdelect@juno.com> Message-ID: <48B9DEF5.3030400@ieee.org> corby d dawson wrote: > Hi, > > I am playing with an Austron 1250B and I'd like to add a fine frequency > adjust. > > The data sheet I have on the 1150 oscillator inside indicates that the > EFC input is an option. > > Anyone have a schematic for the 1250B that shows how the 1150 is wired > in. > > If no EFC on this unit I'll be getting rid of it. > > Thanks, > > Corby Dawson My 1250A manual shows the EFC being brought out to the rear panel, The front panel EFC is "over powered" by the voltage put on the rear panel connection. My manual has two interconnection diagrams for the wiring. They both show the BNC connector on the rear. The external EFC is spec.d at + or - 5 Volts Good luck on the B model Bill K7NOM From clintjeffrey at optusnet.com.au Sun Aug 31 01:52:24 2008 From: clintjeffrey at optusnet.com.au (Clint Jeffrey - VK3CSJ) Date: Sun, 31 Aug 2008 15:52:24 +1000 Subject: [time-nuts] New to the list...Hello from Melbourne Message-ID: <0748263F246941B9B14EACDF6EF90164@ACER5630> Hi everyone, Not sure how many folks there are associated with the "time-nuts" list but hi and hello from Melbourne Australia, I've just signed up a couple of days ago and have already been seeing a degree of activity....all very good. I don't know 'how qualified' I am to consider myself a "time nut" but I will say this, over the years with my involvement with Amateur Radio I often tune into the WWV and WWVH and can have the receiver running for hours with the volume just turned down enough to hear the time signals and the odd phase distortion while pottering around in the shack, to me it can be quite pleasing to have that running in the background almost therapeutic! I started out listening around on our gramophone in the family room, I would've been perhaps 8 or 9 years old, this gramophone didn't tune much further than 1840KHz but it allowed me to tune into a group of Amateurs that have been holding a daily AM net at 11:00am for as long as I can remember, called the "Coffee Break Net", this was my first introduction to Ham Radio, 6 years later I would be licensed with my first Call Sign VK3NCO which I held for almost 10 years before upgrading. However long before obtaining my radio license I had a small portable transistor radio that would in between AM stations detected a transmission of blips spaced a second apart, as a youngster curious, I'm think "what is this, why would I be hearing one second tone bursts?....well of course I had the receiver tuned to this for awhile and it didn't take long for thee official announcement to be made, something along the lines of..."This is VNG Lyndhurst, Victoria, Australia , on 4.5, 7.5 or 12MHz, VNG is a Time Signal Transmission of the Post Masters General Office" it went something like that, I'm now 48 years old I can still remember those transmissions, Lyndhurst was only 10 Kilometers away from where I lived, in fact I'm still only about 15 Kilometers from the old site now. But as a young kid I was so fascinated in wanting to know where these transmissions were coming from and because the announcement said Lyndhurst my mother and I took off one afternoon on our push bikes for a ride south to find this place. Wow!...I couldn't believe my eyes, despite being able to see the looming Antenna systems from a far distance down the road, this Antenna Farm was something to be had! Long wires running between wooden poles going a good 75 to 80 feet into the air, to a young lad they actually seemed hundreds of feet high!, of course these antennas were Rombic's type Antennas, Lyndhurst didn't only just transmit a Time Service but it was also a major Broadcast Station for Radio Australia too. Anyway...after seeing all this my mind just simply wanted to know more and tuning into VNG became a regular thing to do, to a point where I believe I have developed a good sense of timing, at least at one second intervals!! Well...to say the least, every clock including my watch is usually adjusted "spot-on" time, Lyndhurst was always used to do this, although more often now I would use the telephone time service!...but, but, I would still use VNG Lyndhurst...if it was still around. The area where VNG/Radio Australia was is now a housing estate, all those beautiful Antenna systems including a Log Periodic have all gone, I had a chance once to tour the site, and one time because I worked for NEC I had a chance to do some work in a repair shop on site! Information on VNG can be found here http://tufi.alphalink.com.au/time/nsc_vng_leaflet.pdf just in case you already didn't know, its closure happened some time back, pardon the pun....And this is the thing now, Australia no longer supports a HF Radio Time Signal Service, long gone, WWV on 10MHz is about the only good signal heard here in Melbourne, I hear the 2.5MHz transmissions but never strong enough to be able to hear the voice announcements, same for the 20MHz transmissions rarely heard here, 5 and 10MHz are usually the best, it's a pity we don't have something running down around 10KHz, we use to have an Omega Transmitter in Yarram Gippsland, on 10.3KHz which is still there but not operating as a Omega Station, what's the problem in making it a Time Signal Service?....oh well As for me now, there are a couple of interests, I'm wanting to put together a receiver operating at 8.4GHz where the PLO is referenced (10MHz) from a OCXO which in turn is getting it's reference from a GPS Rx with a 10KHz output, all for the sake of increased stability, plus I have an interest in Amateur Radio Astronomy together with a small group from the Astronomical Society of Victoria (ASV) we are establishing a site here in mid Victoria, one of three, there will be some projects that will require a GPS timing for accuracy. My apologies for a long intro... Cheers Clint Jeffrey - VK3CSJ Melbourne. Aust. http://www.vk3csj.com http://www.qsl.net/vk3csj From stanw1le at verizon.net Sun Aug 31 08:58:46 2008 From: stanw1le at verizon.net (Stan, W1LE) Date: Sun, 31 Aug 2008 08:58:46 -0400 Subject: [time-nuts] New to the list...Hello from Melbourne In-Reply-To: <0748263F246941B9B14EACDF6EF90164@ACER5630> References: <0748263F246941B9B14EACDF6EF90164@ACER5630> Message-ID: <48BA9586.20707@verizon.net> Hello Clint, Welcome to the group. For the accurate (stabilized) LO for the 8 GHZ receiver, consider the new product offering from www.downeastmicrowave.com They are offering a synthesized LO that uses a 10 MHz external reference. Also consider the www.n5ac.com product offering for a USB/PC programmable microwave LO. May be more appropriate for 8 GHz. Can be programmed to use a 2-26 MHz reference. Pricing is cost effective for a ham. Phase noise performance, though not spectacular, may be quite workable. Stan, W1LE FN41sr Cape Cod Clint Jeffrey - VK3CSJ wrote: > Hi everyone, > Not sure how many folks there are associated with the "time-nuts" list but hi and hello from Melbourne Australia, I've just signed up a couple of days ago and have already been seeing a degree of activity....all very good. From dave.g0dja at tiscali.co.uk Sun Aug 31 09:21:07 2008 From: dave.g0dja at tiscali.co.uk (David Ackrill) Date: Sun, 31 Aug 2008 14:21:07 +0100 Subject: [time-nuts] New to the list...Hello from Melbourne In-Reply-To: <0748263F246941B9B14EACDF6EF90164@ACER5630> References: <0748263F246941B9B14EACDF6EF90164@ACER5630> Message-ID: <48BA9AC3.7040204@tiscali.co.uk> Clint Jeffrey - VK3CSJ wrote: > As for me now, there are a couple of interests, I'm wanting to put together a receiver operating at 8.4GHz where the PLO is referenced (10MHz) from a OCXO which in turn is getting it's reference from a GPS Rx with a 10KHz output, all for the sake of increased stability, plus I have an interest in Amateur Radio Astronomy together with a small group from the Astronomical Society of Victoria (ASV) we are establishing a site here in mid Victoria, one of three, there will be some projects that will require a GPS timing for accuracy. > You might want to take a look at Kuhne Electronics, who do downconverters for VHF/UHF Radio Astronomy, as well as Amateur Band microwave transverters at http://www.kuhne-electronic.de/en/shop/145_Down_Converters An old mate of mine now lives in Aus and is building antennas for 23cm and getting involved with UHF activity. Dave (G0DJA) From james.p.lux at jpl.nasa.gov Sun Aug 31 11:20:47 2008 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 31 Aug 2008 08:20:47 -0700 Subject: [time-nuts] New to the list...Hello from Melbourne In-Reply-To: <0748263F246941B9B14EACDF6EF90164@ACER5630> References: <0748263F246941B9B14EACDF6EF90164@ACER5630> Message-ID: ________________________________________ From: time-nuts-bounces at febo.com [time-nuts-bounces at febo.com] On Behalf Of Clint Jeffrey - VK3CSJ [clintjeffrey at optusnet.com.au] Sent: Saturday, August 30, 2008 10:52 PM To: time-nuts at febo.com Subject: [time-nuts] New to the list...Hello from Melbourne As for me now, there are a couple of interests, I'm wanting to put together a receiver operating at 8.4GHz where the PLO is referenced (10MHz) from a OCXO which in turn is getting it's reference from a GPS Rx with a 10KHz output, all for the sake of increased stability, plus I have an interest in Amateur Radio Astronomy together with a small group from the Astronomical Society of Victoria (ASV) we are establishing a site here in mid Victoria, one of three, there will be some projects that will require a GPS timing for accuracy. --------------- 8.4 GHz as in the deep space Space to Earth band, or just below? What kind of signals are you looking to receive? Depending on what you're looking for, performance wise, the traditional approach is a DRO locked to the reference with a conventional PLL using a sampling phase detector. However, Hittite now sells some nice GaAs VCOs and VCO/PLLs in that band that you might want to take a look at, especially if you need wide tuning range (it's a real bear to get a quiet DRO to tune over a 50 MHz range). In some tests at JPL, the MMIC outperforms the DRO quite nicely. You can either do a direct "divide down from 8GHz" into a PFD for the loop, driving the reference from a DDS, which is driven from your XO.. OR.. you can mix the 8.4 GHz down with a harmonic mixer driven by a XO. You mix down to some practical IF in the tens of MHz, then, run that into the PLL where you compare to the DDS. The approach depends on your particular phase noise and tunability requirement. Jim Lux From james.p.lux at jpl.nasa.gov Sun Aug 31 11:26:52 2008 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 31 Aug 2008 08:26:52 -0700 Subject: [time-nuts] New to the list...Hello from Melbourne In-Reply-To: <0748263F246941B9B14EACDF6EF90164@ACER5630> References: <0748263F246941B9B14EACDF6EF90164@ACER5630> Message-ID: More on building low noise 8.4 GHz synthesizers: http://ipnpr.jpl.nasa.gov/progress_report/42-166/166A.pdf You can probably put one together using eval boards from the mfrs for <$500 (1 board for the VCO/PLL, 1 for the loop filter, 1 for the DDS) From w1ksz at earthlink.net Sun Aug 31 13:12:38 2008 From: w1ksz at earthlink.net (Richard W. Solomon) Date: Sun, 31 Aug 2008 10:12:38 -0700 (GMT-07:00) Subject: [time-nuts] New to the list...Hello from Melbourne Message-ID: <4967370.1220202758695.JavaMail.root@mswamui-andean.atl.sa.earthlink.net> Must I hunt and peck through the entire site to find this ? A little more direction would be helpful. Tnx, Dick, W1KSZ -----Original Message----- >From: "Stan, W1LE" >Sent: Aug 31, 2008 5:58 AM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] New to the list...Hello from Melbourne > >Hello Clint, > >Welcome to the group. > >For the accurate (stabilized) LO for the 8 GHZ receiver, > >consider the new product offering from www.downeastmicrowave.com > >They are offering a synthesized LO that uses a 10 MHz external reference. > >Also consider the www.n5ac.com product offering for a USB/PC >programmable microwave LO. >May be more appropriate for 8 GHz. Can be programmed to use a 2-26 MHz >reference. > >Pricing is cost effective for a ham. >Phase noise performance, though not spectacular, may be quite workable. > >Stan, W1LE FN41sr Cape Cod > > > > > >Clint Jeffrey - VK3CSJ wrote: >> Hi everyone, >> Not sure how many folks there are associated with the "time-nuts" list but hi and hello from Melbourne Australia, I've just signed up a couple of days ago and have already been seeing a degree of activity....all very good. > >_______________________________________________ >time-nuts mailing list -- 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 Sun Aug 31 14:36:23 2008 From: james.p.lux at jpl.nasa.gov (Lux, James P) Date: Sun, 31 Aug 2008 11:36:23 -0700 Subject: [time-nuts] low noise 8.4 GHz LOs RE: New to the list...Hello from Melbourne Message-ID: ________________________________________ From: time-nuts-bounces at febo.com [time-nuts-bounces at febo.com] On Behalf Of Stan, W1LE [stanw1le at verizon.net] Sent: Sunday, August 31, 2008 5:58 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] New to the list...Hello from Melbourne Hello Clint, Welcome to the group. For the accurate (stabilized) LO for the 8 GHZ receiver, consider the new product offering from www.downeastmicrowave.com They are offering a synthesized LO that uses a 10 MHz external reference. Also consider the www.n5ac.com product offering for a USB/PC programmable microwave LO. May be more appropriate for 8 GHz. Can be programmed to use a 2-26 MHz reference. ----------- I think these are basically the same thing (at least the DEMI site talks about their A32 as being designed by N5AC, and the picture looks identical) This is also basically a 1.x GHz synthesizer, to get up to 8.x, you'd need to multiply it up (which DEMI sells stuff for). The question might be about which scheme is overall best: a PLL locked source with a VCO at 1-2 GHz multiplied up a VCO source 8GHz locked to the reference, either directly, or after being mixed down For either, whether you divide the RF down before running it into a PFD, or if you use a SPD at the RF frequency And, I suppose, direct multiplication through a bunch of steps (or in one fell swoop with a comb generator and a filter) Probably depends on your specific needs, in terms of tunability, noise close and far, and power consumption. It's not something which is cookbook, or for which you can just go look up the equations for all the topologies and trade it off. (or maybe it is.. there might be some recent text that sort of covers them all) Jim Lux Pricing is cost effective for a ham. Phase noise performance, though not spectacular, may be quite workable. Stan, W1LE FN41sr Cape Cod Clint Jeffrey - VK3CSJ wrote: > Hi everyone, > Not sure how many folks there are associated with the "time-nuts" list but hi and hello from Melbourne Australia, I've just signed up a couple of days ago and have already been seeing a degree of activity....all very good. _______________________________________________ time-nuts mailing list -- 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 bpowell at intrex.net Sun Aug 31 14:37:40 2008 From: bpowell at intrex.net (Bill Powell) Date: Sun, 31 Aug 2008 14:37:40 -0400 Subject: [time-nuts] New to the list...Hello from Melbourne In-Reply-To: <4967370.1220202758695.JavaMail.root@mswamui-andean.atl.sa.earthlink.net> References: <4967370.1220202758695.JavaMail.root@mswamui-andean.atl.sa.earthlink.net> Message-ID: <48BAE4F4.2010307@intrex.net> Found this on the main website page: [1]http://www.downeastmicrowave.com/A32.htm Regards, Bill Powell af4jg -------- Original Message -------- Subject: Re: [time-nuts] New to the list...Hello from Melbourne Date: Sun, 31 Aug 2008 10:12:38 -0700 (GMT-07:00) From: Richard W. Solomon [2] Reply-To: Richard W. Solomon [3], Discussion of precise time and frequency measurement [4] To: Discussion of precise time and frequency measurement [5] Must I hunt and peck through the entire site to find this ? A little more direction would be helpful. Tnx, Dick, W1KSZ -----Original Message----- >From: "Stan, W1LE" [6] >Sent: Aug 31, 2008 5:58 AM >To: Discussion of precise time and frequency measurement [7] >Subject: Re: [time-nuts] New to the list...Hello from Melbourne > >Hello Clint, > >Welcome to the group. > >For the accurate (stabilized) LO for the 8 GHZ receiver, > >consider the new product offering from [8]www.downeastmicrowave.com > >They are offering a synthesized LO that uses a 10 MHz external reference. > >Also consider the [9]www.n5ac.com product offering for a USB/PC >programmable microwave LO. >May be more appropriate for 8 GHz. Can be programmed to use a 2-26 MHz >reference. > >Pricing is cost effective for a ham. >Phase noise performance, though not spectacular, may be quite workable. > >Stan, W1LE FN41sr Cape Cod > > > > > >Clint Jeffrey - VK3CSJ wrote: >> Hi everyone, >> Not sure how many folks there are associated with the "time- nuts" list but hi and hello from Melbourne Australia, I've just signed up a coup le of days ago and have already been seeing a degree of activity....all very goo d. > >_______________________________________________ >time-nuts mailing list -- [10]time-nuts at febo.com >To unsubscribe, go to [11]https://www.febo.com/cgi-bin/mailman/listinfo/time-nu ts >and follow the instructions there. _______________________________________________ time-nuts mailing list -- [12]time-nuts at febo.com To unsubscribe, go to [13]https://www.febo.com/cgi-bin/mailman/listinfo/time-nut s and follow the instructions there. References 1. http://www.downeastmicrowave.com/A32.htm 2. mailto:w1ksz at earthlink.net 3. mailto:w1ksz at earthlink.net 4. mailto:time-nuts at febo.com 5. mailto:time-nuts at febo.com 6. mailto:stanw1le at verizon.net 7. mailto:time-nuts at febo.com 8. http://www.downeastmicrowave.com/ 9. http://www.n5ac.com/ 10. mailto:time-nuts at febo.com 11. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts 12. mailto:time-nuts at febo.com 13. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts From namichie at gmail.com Sun Aug 31 18:43:45 2008 From: namichie at gmail.com (Neville Michie) Date: Mon, 1 Sep 2008 08:43:45 +1000 Subject: [time-nuts] TBOLT communications Message-ID: <2FA1FAF9-98CC-4968-A6CE-2E68F2020B14@gmail.com> Hello all, I received my TBOLT from TAPR and proceeded to stoke it up. However I have not been able to get response from TBOLTMON. I use a laptop with a USB port driving a USB-serial converter marked N287. The laptop, unfortunately, runs VISTA. However I can drive an HP Z3815A with a null modem cable and a GCRU/D with a straight cable, and I can also drive HOBO data loggers with these USB-serial converters. With VISTA there is always a lot of experimenting to find the allocated COM port number and right baud rate etc. Whatever I do I cannot get a response from the TBOLT. Preliminary poking with a CRO probe shows some signals on both pin 3 and pin 2 of the RS232 lead. Is it possible to accidentally put the TBOLT in a state where it does not listen? Does it have RS232 requirements that the serial converted does not fit? I would be thankful of any good suggestions, cheers, Neville Michie From bruceraymond at ameritech.net Sun Aug 31 19:16:00 2008 From: bruceraymond at ameritech.net (Bruce Raymond) Date: Sun, 31 Aug 2008 19:16:00 -0400 Subject: [time-nuts] TBOLT communications In-Reply-To: <2FA1FAF9-98CC-4968-A6CE-2E68F2020B14@gmail.com> References: <2FA1FAF9-98CC-4968-A6CE-2E68F2020B14@gmail.com> Message-ID: <48BB2630.6040200@ameritech.net> Hi Neville, I just put power to my Tbolt yesterday, so this is fresh in my mind. I'm running Vista w/SP1 and also running through a USB-RS232 converter. I wasn't getting a response out of the monitor program until I noticed that it was set for odd parity. It should be no parity (9600-N-8-1). I had also hooked the 10 MHz output to a scope to verify that something was happening. It showed a sine wave. Regards, Bruce Raymond/ND8I bruce at raymondtech.net Neville Michie wrote: > Hello all, > I received my TBOLT from TAPR and proceeded to stoke it up. > However I have not been able to get response from TBOLTMON. > I use a laptop with a USB port driving a USB-serial converter marked > N287. > The laptop, unfortunately, runs VISTA. However I can drive an HP Z3815A > with a null modem cable and a GCRU/D with a straight cable, and I can > also drive > HOBO data loggers with these USB-serial converters. With VISTA there > is always a > lot of experimenting to find the allocated COM port number and right > baud rate etc. > Whatever I do I cannot get a response from the TBOLT. > Preliminary poking with a CRO probe shows some signals on both pin 3 > and pin 2 > of the RS232 lead. > Is it possible to accidentally put the TBOLT in a state where it does > not listen? > Does it have RS232 requirements that the serial converted does not fit? > I would be thankful of any good suggestions, > 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. > > From kirbybq at bellsouth.net Sun Aug 31 23:13:31 2008 From: kirbybq at bellsouth.net (Brian Kirby) Date: Sun, 31 Aug 2008 22:13:31 -0500 Subject: [time-nuts] Thunderbolt self-survey results... In-Reply-To: <48B9053D.40607@clanbaker.org> References: <48B9053D.40607@clanbaker.org> Message-ID: <48BB5DDB.2010601@bellsouth.net> google "egm96" and "wgs84" to find about the geodetics used in GPS. there is also an old paper I believe its titled "geodesy for the layman" that will get you are started Your topo map was probably NAVD 1929, a different vertical datum. Brian Kd4FM Michael Baker wrote: > Hello, All-- > > My Thunderbolt seems to be able to determine its > Lat and Lon location coordinates with reasonable accuracy. > > However, after completing its self-survey it thinks > its elevation is 11.2 meters when the actual elevation > of its antenna (on my house roof) is 28.4 meters. > > I arrived at this value by looking at the USGS topo > map of my property, noting the elevation ABMSL where > my house is located and adding the distance from > the ground to the GPS antenna on my roof and coming up > with 28.4 meters. > > Should I store this value into POSITION/ALTITUDE? > > If I enter this value into ALTITUDE, then what? > Should I then SAVE SEGMENT? SET ACCURATE POSITION? > > Thanks, > > Mike Baker > WA4HFR > Micanopy, FL > > > > _______________________________________________ > time-nuts mailing list -- time-nuts at febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >