Re: [time-nuts] Symmetricom 5071A
From: "Dave Carlson" <[EMAIL PROTECTED]> Subject: Re: [time-nuts] Symmetricom 5071A Date: Sun, 26 Jun 2005 19:56:36 -0700 Message-ID: <[EMAIL PROTECTED]> > Hello Magnus, Hi Dave, > Your question: > > "Or, to put it in another form, do you know where the HP/Agilent tubes are > actually made (I.he. not the total clock assembly)?" > > Since the early 1970s made in Santa Clara CA, corner of Stevens Creek Blvd > and Lawrence Expressway, at the site once owned by HP and later by Agilent. > Before that they were made by HP in Palo Alto, Ca. > > Never has Symmetricom or any other CBT manufacturer made CBTs for HP or > Agilent. HP/Agilent always made > their own. > > Other CBT manufacturers have made a CBT that could be retrofitted into a > 5061A/B Cesium Beam Frequency Standard, but not the 5071a. OK. Great. Thanks for the effort. I will talk to my friend today and ask what he has to say about it. He was probably missinformed, but he sounded quite certain. He probably missed out on that detail. Cheers, Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Z3801A good GPS-receiver
Magnus Danielson wrote: Yes, I've noticed all the links, software and all that. Being a *nix guy I naturally care to have the source and control. You're welcome to my Perl stuff -- not sure if I have it on my website under http://www.febo.com/time-freq/gps (look for the Z3801A link) but if you don't see it, drop me a line and I'll get it for you. One of the things I have failed to find is the type of GPS receiver operation in action. I assume that it is a C/A signal (it only says L1), but does it use HPs brilliant solution to track both carrier and code variations to make compensations similar to the L1/L2 P(Y) code-less tracking? I think I have the article around here somewhere. It is not a carrier-phase type of receiver as I have gathered it. Right? The receiver is the old 6 channel Motorola Oncore, using standard L1 C/A signal. John ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Z3801A good GPS-receiver
From: John Ackermann N8UR <[EMAIL PROTECTED]> Subject: Re: [time-nuts] Z3801A good GPS-receiver Date: Mon, 27 Jun 2005 08:42:27 -0400 Message-ID: <[EMAIL PROTECTED]> > Magnus Danielson wrote: > > > Yes, I've noticed all the links, software and all that. Being a *nix guy I > > naturally care to have the source and control. > > You're welcome to my Perl stuff -- not sure if I have it on my website > under http://www.febo.com/time-freq/gps (look for the Z3801A link) but > if you don't see it, drop me a line and I'll get it for you. I think I actually looked at the code the other night. ;O) > > One of the things I have failed to find is the type of GPS receiver > > operation > > in action. I assume that it is a C/A signal (it only says L1), but does it > > use > > HPs brilliant solution to track both carrier and code variations to make > > compensations similar to the L1/L2 P(Y) code-less tracking? I think I have > > the article around here somewhere. It is not a carrier-phase type of > > receiver > > as I have gathered it. Right? > > The receiver is the old 6 channel Motorola Oncore, using standard L1 C/A > signal. The thing is, in the article "Recovering UTC(USNO,MC) with increased accuracy using a fixed L1-CA code, GPS receiver" by R.P. Giffard, Agilent Lab PTTI-32 (page 97 in the compendium), they apply it on a Motorola Oncore. But then I did not recall the date, and the PTTI-32 was in 2000 which is too late for the Z3801A I guess. Interesting article, but it was some time I read it myself. Cheers, Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
RE: [time-nuts] Symmetricom 5071A
> Never has Symmetricom or any other CBT manufacturer made CBTs for HP or > Agilent. HP/Agilent always made > their own. > I thought the CBT's were originally made by Varian for HP. That's why the CBT burn in fixtures (still in use today AFAIK) are marked "Varian Associates". In any event, the 5071 CBTs have never been outsourced. Rick Karlquist ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Symmetricom 5071A
From: "Richard \(Rick\) Karlquist \(N6RK\)" <[EMAIL PROTECTED]> Subject: RE: [time-nuts] Symmetricom 5071A Date: Mon, 27 Jun 2005 14:42:40 -0700 Message-ID: <[EMAIL PROTECTED]> Rick, > > Never has Symmetricom or any other CBT manufacturer made CBTs for HP or > > Agilent. HP/Agilent always made > > their own. > > > > I thought the CBT's were originally made by Varian for HP. Until HP aquired the whole line, and continued much of the research and development. It becomes evident both by public sources about history (such as those on the UFFC site) and when doing patent archeology. > That's why the CBT burn in fixtures (still in use today AFAIK) > are marked "Varian Associates". Interesting. Same shape of the tubes or have they been adapted over time? > In any event, the 5071 CBTs have never been outsourced. I might add that my source said the same thing, when asked. Cheers, Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] Code for phase noise and allan variance
Does anyone have code which will take an amplitude vs. time input stream and output phase noise and/or allan variance? Thanks, Matt P.S. I was forwarded a message from the list about the USRP. The USRP does have an input for an external clock source, so feel free to feed it from your Hydrogen Maser or whatever else you have laying around :) The reference needs to be at 64 MHz or lower. You ADC sample rate can be 1/4*fref, 1/2*fref, fref, or 2*fref, as long as the final rate is <= 64 MHz. The DAC sample rate will always be 2*fref. Matt ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Code for phase noise and allan variance
In message <[EMAIL PROTECTED]>, Matt Ettus writes: >Does anyone have code which will take an amplitude vs. time input >stream and output phase noise and/or allan variance? http://phk.freebsd.dk/misc/Allan.tgz will do allan, modified allan and FFT. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | 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@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Code for phase noise and allan variance
From: Matt Ettus <[EMAIL PROTECTED]> Subject: [time-nuts] Code for phase noise and allan variance Date: Mon, 27 Jun 2005 15:22:25 -0700 Message-ID: <[EMAIL PROTECTED]> Matt, > Does anyone have code which will take an amplitude vs. time input > stream and output phase noise and/or allan variance? I guess you could do it that way, but really, it would be alot of data at a high sampling rate to make any usefullness. The single-shot resolution is just one of the limiting parameters and a sampled system has a bandwidth limitation (good old Nyquist) which also puts a limitation on single-shot resolution. I would say that slope estimation would make a poor indicator. Allen variance is calculated from accurate time samples rather than amplitude samples. Time interval counting is really the best way to reduce data, and it must be back-to-back (which is possible with sampled data, but much of the data is just waste of time and storage). Much of the pre-processing would be to convert the sampled stream into time interval counts anyway. Basically doing the trigger point detection and time estimates in software. Lets just say that I'm sceptical. Time Interval Counters isn't rocket science and nor is ADCs, but they are very different animals for very different needs. However, performing very accurate timed ADC is in itself a very interesting thing. Cheers, Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Code for phase noise and allan variance
On 6/27/05, Poul-Henning Kamp <[EMAIL PROTECTED]> wrote: > In message <[EMAIL PROTECTED]>, Matt Ettus writes: > > >Does anyone have code which will take an amplitude vs. time input > >stream and output phase noise and/or allan variance? > > http://phk.freebsd.dk/misc/Allan.tgz > > will do allan, modified allan and FFT. Thanks! I tried to compile on Linux, got this: [EMAIL PROTECTED] Allan]$ make Makefile:9: *** missing separator. Stop. I removed the last line in the Make file and got this: [EMAIL PROTECTED] Allan]$ make cc -g -Wall -staticallan.c -o allan allan.c:19:27: floatingpoint.h: No such file or directory allan.c: In function `main': allan.c:722: warning: implicit declaration of function `fpsetmask' allan.c:722: error: `FP_X_UFL' undeclared (first use in this function) allan.c:722: error: (Each undeclared identifier is reported only once allan.c:722: error: for each function it appears in.) make: *** [allan] Error 1 Looks like I'm missing floatingpoint.h. A BSD thing? Matt ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Code for phase noise and allan variance
In message <[EMAIL PROTECTED]>, Magnus Danielson write s: >> Does anyone have code which will take an amplitude vs. time input >> stream and output phase noise and/or allan variance? > >I guess you could do it that way, but really, it would be alot of data at a >high sampling rate to make any usefullness. You're wrong Magnus :-) You overlook that the A/D converter gives you much more information about the timing of a zero-crossing than just the sample number: You can interpolate the zero-crossing to subsample accuracy and that way get far *better* resolution than the HP5370 which otherwise holds the single-shot crown. I have played a lot with this with a 12bit 20MHz ADC card I have, and the USRP does 64MHz sampling which is a lot better. If your signal is relatively noise-free and of good amplitude I would not at all be surprised to see single-shot timings well into the pico-second regime, (compared to the 15nsec a digital use of 64MHz would give). And as I suggested in an email a couple of days ago: It would be almost perfect for phase-noise measurements as well, thanks to the dual inputs. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | 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@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Code for phase noise and allan variance
In message <[EMAIL PROTECTED]>, Matt Ettus writes: >> >> http://phk.freebsd.dk/misc/Allan.tgz >> >> will do allan, modified allan and FFT. > >Thanks! > >I tried to compile on Linux, got this: > >[EMAIL PROTECTED] Allan]$ make >Makefile:9: *** missing separator. Stop. Yes, sorry, the thing is written on FreeBSD for my private use so portability was not a major issue. >[EMAIL PROTECTED] Allan]$ make >cc -g -Wall -staticallan.c -o allan >allan.c:19:27: floatingpoint.h: No such file or directory >allan.c: In function `main': >allan.c:722: warning: implicit declaration of function `fpsetmask' >allan.c:722: error: `FP_X_UFL' undeclared (first use in this function) >allan.c:722: error: (Each undeclared identifier is reported only once >allan.c:722: error: for each function it appears in.) >make: *** [allan] Error 1 > > >Looks like I'm missing floatingpoint.h. A BSD thing? Try substituing instead. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | 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@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Code for phase noise and allan variance
Hi Matt -- I have a perl script, based on some code from Tom Van Baak, that does basic AVAR stuff. Poul-Henning Kemp has posted some C code to do the same thing -- you might take a look at the list archive to find that (https://www.febo.com/pipermail/time-nuts). John Matt Ettus wrote: >Does anyone have code which will take an amplitude vs. time input >stream and output phase noise and/or allan variance? > >Thanks, >Matt > >P.S. I was forwarded a message from the list about the USRP. The >USRP does have an input for an external clock source, so feel free to >feed it from your Hydrogen Maser or whatever else you have laying >around :) > >The reference needs to be at 64 MHz or lower. You ADC sample rate can >be 1/4*fref, 1/2*fref, fref, or 2*fref, as long as the final rate is ><= 64 MHz. > >The DAC sample rate will always be 2*fref. > >Matt > >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] HP5334A Opt 010
Hello Javier, >From the HP5334A Manual Parts List: 05334-60001 (Standard) and 05334-6006 (Option 10) A1 Main Board Assemblies are identical except for C8, C100 and Y1. The Field Installation Procedure for Option 010 includes the following: Remove A1C8 and install A1C100 using the soldering iron. Nothing is mentioned about A1Y1 in this section, so it may be OK to leave this in place. Looking through the parts list, I notice that C8 and C100 (.01 uF +- 20% 50VDC CER) have the same part number, 0160-4554, so all that should be necessary is to move C8 to the C100 position on the main board. If you don't have the Option 010 Oven Oscillator Support Board, you could also "borrow" the needed supply voltages from the 6-pin connector on the main board, feed them through the rear panel, then make your own interface board, and mount this board and the HP10811 oscillator in a separate enclosure. You could then feed the 10 MHz signal from the HP10811 back through the Time Base In/Out connector on the rear panel. In this case you would not need to make any modifications to the main board. You could also make your own power supply for the external oscillator to have a complete, stand-alone 10 MHZ source, which you could use for other applications. Sorry to bother the list, but this is NOT off-topic, and may be of interest to other members on the list. Regards, -- Flemming Larsen, KB6ADS, OZ6OI ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] HP5334A Opt 010
Thanks, Flemming! Best regards, Javier, EA1CRB Flemming Larsen wrote: Hello Javier, From the HP5334A Manual Parts List: 05334-60001 (Standard) and 05334-6006 (Option 10) A1 Main Board Assemblies are identical except for C8, C100 and Y1. The Field Installation Procedure for Option 010 includes the following: Remove A1C8 and install A1C100 using the soldering iron. Nothing is mentioned about A1Y1 in this section, so it may be OK to leave this in place. Looking through the parts list, I notice that C8 and C100 (.01 uF +- 20% 50VDC CER) have the same part number, 0160-4554, so all that should be necessary is to move C8 to the C100 position on the main board. If you don't have the Option 010 Oven Oscillator Support Board, you could also "borrow" the needed supply voltages from the 6-pin connector on the main board, feed them through the rear panel, then make your own interface board, and mount this board and the HP10811 oscillator in a separate enclosure. You could then feed the 10 MHz signal from the HP10811 back through the Time Base In/Out connector on the rear panel. In this case you would not need to make any modifications to the main board. You could also make your own power supply for the external oscillator to have a complete, stand-alone 10 MHZ source, which you could use for other applications. Sorry to bother the list, but this is NOT off-topic, and may be of interest to other members on the list. Regards, -- Flemming Larsen, KB6ADS, OZ6OI ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts