[time-nuts] time-nuts Digest, Vol 81, Issue 57

Sun Apr 17 23:50:48 UTC 2011

You ARE the MAN!

73
Dave K1WHS
----- Original Message ----- 
From: <time-nuts-request at febo.com>
To: <time-nuts at febo.com>
Sent: Sunday, April 17, 2011 4:22 AM
Subject: time-nuts Digest, Vol 81, Issue 57

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> Today's Topics:
>
>   1. BNC Question (Brucekareen at aol.com)
>   2. Re: BNC Question (Rick Karlquist)
>   3. Re: BNC Question (Chuck Harris)
>   4. Re: Datronn Wavetek 4910 (Oz-in-DFW)
>   5. Re: PIC processor CTMU module used for sub-ns TIC
>      applications? (cook michael)
>   6. Re: PIC processor CTMU module used for sub-ns TIC
>      applications? (Bruce Griffiths)
>   7. Re: PIC processor CTMU module used for sub-ns TIC
>      applications? (Poul-Henning Kamp)
>   8. Re: LightSquared gets at least some political attention
>      (Magnus Danielson)
>   9. Vectron Oscillator Model 217-5604 Info search (Arnold Tibus)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sat, 16 Apr 2011 21:02:20 EDT
> From: Brucekareen at aol.com
> To: time-nuts at febo.com
> Subject: [time-nuts] BNC Question
> Message-ID: <13449.219ed47.3adb961c at aol.com>
> Content-Type: text/plain; charset="US-ASCII"
>
> An Amphenol document discussing the mating compatibility of their 50-ohm
> and 75-ohm BNC connectors can be found here
> _http://www.amphenolrf.com/products/bnc.asp?N=0&sid=46B11E806D75617F_
> (http://www.amphenolrf.com/products/bnc.asp?N=0&sid=46B11E806D75617F)  .
>
> Bruce, KG6OJI
>
>
>
> ------------------------------
>
> Message: 2
> Date: Sat, 16 Apr 2011 18:55:34 -0700
> From: "Rick Karlquist" <richard at karlquist.com>
> To: "Discussion of precise time and frequency measurement"
> <time-nuts at febo.com>
> Subject: Re: [time-nuts] BNC Question
> Message-ID:
> <01ec8a7b0e22e9d28beeb4002ef88181.squirrel at webmail.sonic.net>
> Content-Type: text/plain;charset=iso-8859-1
>
> Oz-in-DFW wrote:
>>
>> BNCs can be as good as TNCs when properly applied, but the bayonet
>> mechanism allows too much mechanical alignment play for reasonable
>> reliability past a GHz or so.  If they are properly installed and the
>> cable is not allowed to put a radial or significant tensile load they
>> perform as well as a TNC and close to an N.  For all that, I won't use
>
> FWIW:
>
> The guts of a BNC/TNC is very similar if not identical to a type N,
> which is good for at least 12.4 GHz.  The Agilent 13 GHz scopes
> have "precision" (IE tight fitting) BNC connectors on the probes.
> All of which of course doesn't mean the Asian BNC's you bought
> at the hamfest are any good.
>
> Rick N6RK
>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Sun, 17 Apr 2011 00:04:48 -0400
> From: Chuck Harris <cfharris at erols.com>
> To: Discussion of precise time and frequency measurement
> <time-nuts at febo.com>
> Subject: Re: [time-nuts] BNC Question
> Message-ID: <4DAA66E0.6070506 at erols.com>
> Content-Type: text/plain; charset=UTF-8; format=flowed
>
> Rick Karlquist wrote:
>
>> FWIW:
>>
>> The guts of a BNC/TNC is very similar if not identical to a type N,
>> which is good for at least 12.4 GHz.  The Agilent 13 GHz scopes
>> have "precision" (IE tight fitting) BNC connectors on the probes.
>> All of which of course doesn't mean the Asian BNC's you bought
>> at the hamfest are any good.
>>
>> Rick N6RK
>
> There is a very significant difference between the N and the BNC
> construction with regards to what is the insulator in the transition
> section between the male and female connector:  With the BNC (and TNC)
> connector(s), the space is filled with an interdigitated plastic
> dielectric.  With the N, the space is filled with air.
>
> -Chuck Harris
>
>
>
> ------------------------------
>
> Message: 4
> Date: Sat, 16 Apr 2011 23:18:56 -0500
> From: Oz-in-DFW <lists at ozindfw.net>
> To: Discussion of precise voltage measurement <volt-nuts at febo.com>
> Cc: Discussion of precise time and frequency measurement
> <time-nuts at febo.com>
> Subject: Re: [time-nuts] Datronn Wavetek 4910
> Message-ID: <4DAA6A30.8010504 at ozindfw.net>
> Content-Type: text/plain; charset=ISO-8859-1
>
> I suspect this was an inadvertent mis-post to time-nuts intended for
> volt-nuts
>
>
> On 4/16/2011 4:01 PM, WB6BNQ wrote:
>> JF,
>>
>> Not meaning to be unfriendly, BUT this list * *  IS NOT  * * a "general" 
>> test equipment repair faculty.
>>
>> The unit in question is a series of regulated voltage sources that are 
>> adjustable.  Being adjustable means it is not absolute.  Equally so, your 
>> 3458A is, likewise, adjustable and is totally dependent upon the 
>> references it was adjusted against.  Besides the type of wires and 
>> corresponding thermals in your connection arrangement, you have the 
>> ambient
>> temperature in the mix.
>>
>> As you state you just bought it used, how do you expect it to be perfect 
>> ?  It has most likely been kicked around for a while and with no known 
>> calibration history, those values do not surprise me at all.  Do you 
>> really think your 3458A is perfect ?  Is your "cal lab" really up to the 
>> job ?  If so, then send your new BOX to them and compare after you
>> get it back.
>>
>> Your question "What is the reference of the replacement batteries ?" is 
>> ambiguous.  If you meant the part number, then open it up and do the 
>> research.  As for the batteries, except for mounting issues, they are 
>> just a power source for all the different regulated supplies that feed 
>> those front panel connectors.
>>
>> Bill....WB6BNQ
>>
>>
>> JF PICARD wrote:
>>
>>> I am looking for the service manual of the Datron Wavetek 4910. I have 
>>> just got  this reference standard from Ebay : is it normal to see 3 
>>> cells at 2 or 3 ?v under 10V  and one at + 13?v (23?C with 3458A just 
>>> calibrated yesterday) or it is an obvious problem with the cell (the 
>>> third one) ? What is the reference of the replacement batteries ? 
>>> Thanks.
>>> _______________________________________________
>>> time-nuts mailing list -- 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 
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>> and follow the instructions there.
>
> -- 
> mailto:oz at ozindfw.net
> Oz
> POB 93167
> Southlake, TX 76092 (Near DFW Airport)
>
>
>
>
>
>
> ------------------------------
>
> Message: 5
> Date: Sun, 17 Apr 2011 07:34:29 +0200
> From: cook michael <michael.cook at sfr.fr>
> To: beale <beale at bealecorner.com>, Discussion of precise time and
> frequency measurement <time-nuts at febo.com>
> Subject: Re: [time-nuts] PIC processor CTMU module used for sub-ns TIC
> applications?
> Message-ID: <4DAA7BE5.5060107 at sfr.fr>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Le 17/04/2011 00:20, beale a ?crit :
>> The application note merely asserts the possibility, but neglects to 
>> present a specific design. Has anyone here attempted to use a PIC CTMU in 
>> that way?
> The app note doesn't give a complete design, but the principle of
> precision time measurement is explained with a corresponding block
> design under "Precision Time Measurement". It relies on A/D sample and
> hold capacitor charging between 2 edge detections. Worth looking into
> though. I expect the data sheets will show how to implement it and
> define its limitations.
>
>> _______________________________________________
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>> To unsubscribe, go to 
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>> and follow the instructions there.
>>
>>
>
>
>
>
>
> ------------------------------
>
> Message: 6
> Date: Sun, 17 Apr 2011 17:37:54 +1200
> From: Bruce Griffiths <bruce.griffiths at xtra.co.nz>
> To: beale <beale at bealecorner.com>, Discussion of precise time and
> frequency measurement <time-nuts at febo.com>
> Subject: Re: [time-nuts] PIC processor CTMU module used for sub-ns TIC
> applications?
> Message-ID: <4DAA7CB2.8060900 at xtra.co.nz>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> beale wrote:
>> I see Microchip application note AN1375 at 
>> http://ww1.microchip.com/downloads/en/AppNotes/01375a.pdf suggests that 
>> the CTMU module included in some recent PIC parts, for example 
>> PIC18F46J11 can be used as a TIC building block for interpolating time 
>> intervals with sub-ns resolution. I gather this module was originally 
>> designed for touch sensing applications; they also mention measurement of 
>> absolute and relative capacitance.
>>
>> The application note merely asserts the possibility, but neglects to 
>> present a specific design. Has anyone here attempted to use a PIC CTMU in 
>> that way?
>>
>> I've been studying Richard McCorkle's PICTIC-II design (1) with an eye to 
>> implementing the digital parts in a CPLD, and so far have a start/stop 
>> counter working (2). I haven't yet started on the analog part of the 
>> circuit, but now I'm wondering if Microchip has already done the work for 
>> me, in a $4 part ? (3)
>>
>> (1) http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:pictic
>> (2) http://bealecorner.org/best/measure/time/CPLD-TIC/
>> (3) 
>> http://parts.digikey.com/1/parts/1671850-ic-pic-mcu-flash-64kb-44-tqfp-pic18f46j11-i-pt.html
>>
>>
> Spotted that feature several months ago.
> It should work well to within the limits of the CTMU module design.
> IIRC the external capacitance needs to be kept low for sub ns resolution.
> Crosstalk from within the PIC chip as well as ground and Vcc bounce may
> be an issue.
>
> A statistical fill the buckets linearity test will allow evaluation the
> integral and differential nonlinearities in such a TDC.
> In this case a relatively unstable source is required to enable such
> testing.
> One of the resistance tuned silicon oscillators available from LTC and
> elsewhere should work well.
>
> Bruce
>
>
>
> ------------------------------
>
> Message: 7
> Date: Sun, 17 Apr 2011 05:42:29 +0000
> From: "Poul-Henning Kamp" <phk at phk.freebsd.dk>
> To: Discussion of precise time and frequency measurement
> <time-nuts at febo.com>
> Cc: beale <beale at bealecorner.com>
> Subject: Re: [time-nuts] PIC processor CTMU module used for sub-ns TIC
> applications?
> Message-ID: <21853.1303018949 at critter.freebsd.dk>
> Content-Type: text/plain; charset=ISO-8859-1
>
> In message <4DAA7BE5.5060107 at sfr.fr>, cook michael writes:
>>Le 17/04/2011 00:20, beale a =E9crit :
>
>>> The application note merely asserts the possibility, but neglects to
>>present a specific design. Has anyone here attempted to use a PIC CTMU
>>in that way?
>
> I tried it when I had a pic18f25j50 in my breadboard anyway, but
> failed to get reliable results.  If you want to play with it, I
> suggest you make an actual PCB and clean/coat it very carefully
> to avoid leaking current or electrostatic fields.
>
> -- 
> 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.
>
>
>
> ------------------------------
>
> Message: 8
> Date: Sun, 17 Apr 2011 09:29:12 +0200
> From: Magnus Danielson <magnus at rubidium.dyndns.org>
> To: time-nuts at febo.com
> Subject: Re: [time-nuts] LightSquared gets at least some political
> attention
> Message-ID: <4DAA96C8.7020003 at rubidium.dyndns.org>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> On 04/17/2011 12:45 AM, Charles P. Steinmetz wrote:
>> John wrote:
>>
>>> IMO, your crack about NTSC is unjustified.
>>>
>>> IMO, NTSC color was a very elegant engineering solution to backwards
>>> compatability. Without that, we could well be still watching B&W.
>>
>> The other contemporary backward-compatible solutions -- PAL and SECAM --
>> did not suffer from the color drift that plagued color NTSC. So, there
>> were superior methods of backward-compatible color insertion available
>> and the FCC still chose the NTSC method. Bad decision, which saddled the
>> US with inferior broadcast video for 60 years -- just as choosing 8VSB
>> has done for digital video in the US.
>
> This is why "Never Twice Same Colour" became an alternative expansion of
> NTSC. If you look at PAL you will see that it was made more resistive to
> multipath phase errors by alternating the polarity of one of the colour
> difference signals on every other field, which by interlacing will cause
> the opposite turn in the colour spectrum on the next line so on average
> they will cancel.
>
> As I recall it, the original choice of colours for the NTSC caused greif
> over time and was in practice changed later. A quick check on the NTSC
> wikipedia article verifies this.
>
> So NTSC didn't get it all quite right.
>
> Also, stepping from 60 fields per second to 60/1,001 fields per second
> still haunts us when PAL stayed at 50 fields per second. For SD-SDI they
> where able to match them up to a common 270 MBd, but for HD-SDI we have
> 1,485 MBd and 1,485/1,001 MBd. This had to be solved with dual
> oscillators in the first products, then with a re-synthesis chip and now
> there is oscillators with dual frequencies which is good enough. This
> 1,001 factor also comes into play with some audio production... so this
> factor remains with changed underlying TV system.
>
> So some of their particular technology choices isn't a good long term
> solution.
>
> NTSC did manage to get a colour solution out of the door, but it wasn't
> the best technological solution for its day.
>
> Cheers,
> Magnus
>
>
>
> ------------------------------
>
> Message: 9
> Date: Sun, 17 Apr 2011 10:22:09 +0200
> From: Arnold Tibus <arnold.tibus at gmx.de>
> To: Time-Nuts <time-nuts at febo.com>
> Subject: [time-nuts] Vectron Oscillator Model 217-5604 Info search
> Message-ID: <4DAAA331.3010809 at gmx.de>
> Content-Type: text/plain; charset=ISO-8859-15
>
> Hi,
> is there anybody in the group who could give me informations of the
> Vectron Crystal Oscillator Model 217-5604?
>
> I got two of this type with 9.995985 MHz and 9.99597 MHz and I think
> these would be good for mixing 10 MHz units down to 4 kHz Audio for
> measurement purpose.
>
> Can dim. is 2" x 2" x 3" with 4 1/4" studs. Electrical connection is
> provided by 7 solder studs and the output connector is an F-SMA.
> It looks like that only 2 contacts were used, so maybe these are not
> OCXOs and not voltage contollable.
> Unfortunately I cannot find anything about this Model in the WWW.
>
> It would be great if anybody could give me some data.
> Many thanks in advance,
> regards
>
> Arnold
>
>
>
> ------------------------------
>
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> End of time-nuts Digest, Vol 81, Issue 57
> ***************************************** 