Re: [time-nuts] [Bulk] Re: [Bulk] Re: [Bulk] Re: Ultra High Stability Time Base Options for 53132A
I have removed the HP Opt 010 board from my 53132A and installed the MV89 variant from Poland. So far, looks good. Having done that, C2, C3, C4, and C5 on the HP 53132-60011 board that I 'modified' to a 53132-60016 board, appear to be .01 uF SMT caps. The 'take home' message here is that the 53132-60011 board, on which C2, C3, C4 and C5 reside, appear to be 10 nF (aka 0.01 uF caps) as best I can measure with my 'Smart Tweezers'. These parts are not on the 53132-60016 board. Charles Steinmetz has annotated the schematic of the 53132-60011 board to clarify some issues as well. Please add these values to your schematics. I'll see if I can make a modification to the schematic and upload the details to Didier's site. Hope this helps. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of J. L. Trantham Sent: Sunday, April 19, 2015 3:39 PM To: 'Discussion of precise time and frequency measurement' Subject: [Bulk] Re: [time-nuts] [Bulk] Re: [Bulk] Re: Ultra High Stability Time Base Options for 53132A If anyone is interested in adding a clearer version of the 53132-60011 board on page 13 of the CLIP for the 53132A, I have redrawn the schematic. I have the values of all components except 4 capacitors that appear to all be the same. I can measure them, if needed, but I will have to remove the unit from my counter. I plan to do that in a few weeks when the MV89 version of the time base arrives. Please let me know if you would like a .PDF of the 'redrawn' schematic. About 2.2 MB file. I also have pictures of the board if anyone needs that as well. Joe ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] TimeLab + sr620
Hello, I've taken a first pass at using TimeLab over the weekend. I wasn't able to get it to work with my SRS sr 620 over RS232. I know that the com port / serial cable and counter are working. I can open terminal, talk to the counter, and make a measurement. When I setup a measurement in TimeLab If I hit the monitor button I don't see any activity. If I start the measurement, Time lab never gets past trying to establish communication with the counter. I'm sure its my fault. Any thoughs? thanks Lincoln ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Tymserve 2100 thinks it's 1995?
My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Sep 17 1995 to May 3 2015 is exactly 1024 weeks. http://www.leapsecond.com/notes/gpswnro.htm On Sun, May 3, 2015 at 7:31 PM, Bob Martin k6...@comcast.net wrote: My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tektronix Sample Heads
Yes, that's about right, Magnus. I believe it depends on how many sampling channels are in use, since there is a factor of two interleaving in some cases (to the best of my memory). That is really the holdoff rate between the acceptance of trigger edges. If the trigger signal rate is lower (such as 10 kHz), that will be the sampling rate. If the trigger signal is at a higher frequency (such as 400 MHz), only one out of every 1,000 trigger edges might be accepted. Each accepted trigger event causes a single sample of the input voltage (relative to the feedback voltage) to be taken. The sampled voltage is significantly attenuated due to sampler loss, so the sampler output is multiplied by the assumed correction factor to change the feedback voltage (which is then measured by a low speed high resolution A/D). If the gain is set correctly, the step response is pretty good, but due to nonlinearity there is a small digital feedback error resulting in slight ringing at the sampling rate. This ringing is often not noticed unless the scope time/div is set to a low value. Sampling oscilloscopes are only undersampled with respect to signals which are not harmonically related to the trigger signal. The sequential equivalent time sampling rate is often several THz/sec. Basic TDR/TDT doesn't need any additional software to get an estimate of the reflected impedance. But the iConnect software (which was developed by a small company which Tektronix purchased many years ago) allows much higher accuracy and removes most of the ambiguity of multiple reflections. It also allows S-parameters to be extracted and SPICE models to be verified. This software isn't free - we have many more software engineers than hardware engineers these days! -- Bill Byrom N5BB On Sun, May 3, 2015, at 04:28 PM, Magnus Danielson wrote: Bill, As I recall it, it has a 400 kS/s rate. Undersampling as it is, if properly used, it is a marvelous tool. The TDR capability had such a live component to it that I miss in newer (but butter calibrated) systems. No wonder I have a system myself these days. The one thing I would love to have, is to be able to run the TDR/TDT post-processing software. I haven't seen any free alternative either. Cheers, Magnus On 04/26/2015 06:26 AM, Bill Byrom wrote: I still work for Tektronix, but not in Service or the sampling scope product line. I'm a Tektronix field RF Application Engineer. You can find the service manual for the SD-24 at: http://www.tek.com/oscilloscope/sd24-manual/sd-24-service-manual But it's not user repairable, so there are no schematics (just block diagrams). The SD-24 was introduced about 25 years ago for the 11801/11802 family of sampling scopes. The SD-24 is a dual TDR sampling head, so it can generate a fast risetime step from either or both outputs. The steps can be the same polarity (for common mode testing) or opposite polarity (for differential mode testing). The sampling bridges measure both the incident (forward) and reflected pulses. The SD-26 is basically the same product without the TDR pulse sources. The SD-22 is a lower noise (and lower bandwidth) version of the SD-26. As pointed out by others, these heads aren't useful without a 11800 or CSA800 family mainframe. The SD-series measure signals using sequential equivalent-time sampling. * Single events can't be measured. Only repeating signals with a low-jitter trigger source can be measured. The trigger must be an externally input signal (unless you use the SD-24 with the internal TDR step source or an external signal pickoff transformer). * Each trigger edge which is accepted by the mainframe is delayed by a precise amount and then used to create a sampling strobe which is sent by the mainframe to the sampling head. * The sampling head (SD-24/26/22) actually measures the error difference between an internal feedback loop and the sampled input voltage. Since the sampling bridge has a high loss, the error voltage is multiplied by the assumed bridge loss to create the new feedback loop voltage. A high resolution low-noise A/D converter measures the loop voltage for the microprocessor-created raster scan display on the CRT. * The sampling system takes around 10 microseconds to reset between triggers. So no more than about 100K triggers and samples can be made per second. It might be a little slower than this - I'm remembering this from my experience over 20 years ago. * The delay from the trigger input to the sampling strobe (sent to the SD-xx sampling head) is sequentially delayed by slightly increasing time delays to create a time domain display. The delay increment between samples can be less than 1 ps (down in the 100 fs range). * Since the signal is not actually sampled in real time, this is called equivalent-time sampling. In
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Additional information -- Power cycling (leaving it off for about 5 minutes) didn't do any good. Once at the correct time/date, it bounces back to 1995 at about 30 seconds after the hour (now to Sep 18, 1995). My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Hi Bob, I've just this minute joined this list, because I Tymserve 2100 unit we have at work has just started doing the same thing, at just gone 1am UT on May 3rd. I've also tried restarting and power cycling (this is somewhat convoluted as the unit is ~3000 miles away from me) but it's firmly stuck in 1995 Ours is currently running Rev 3.1 : 5 ? version Boot Code - Tymserve_2100 Rev 1.1 12/20/1996 13:07:21 Main Code - TymServe_2100 Rev 3.1 08/22/2002 12:15:37 After a power cycle, our unit comes up as follows: 3 ? time JAN 01 1995 00:01:53.687252 After the GPS has locked this changes to: 5 ? time SEP 17 1995 20:14:35.479915 Where 20:14 was the correct UT time. cheers Chris On 05/04/2015 12:31 AM, Bob Martin wrote: My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- - Chris Mottram | Liverpool Telescope Programmer.| Liverpool John Moores University, | email: c.mott...@ljmu.ac.uk Astrophysics Research Institute, | phone: (0151) 904 6591 IC2, Liverpool Science Park, | mobile: 07778650412 146 Brownlow Hill, Liverpool, L3 5RF | www: www.astro.ljmu.ac.uk -- attachment: C_Mottram.vcf___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] GPS data show how Nepal quake disturbed ionosphere
http://www.nasa.gov/jpl/gps-data-show-how-nepal-quake-disturbed-earth-s-upper-atmosphere starting from there I've found also this interesting link http://igs.org/network I was not aware of. Antonio I8IOV ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Lucent KS-24361/Thunderbolt antenna advice sought.
Hi, all I've only recently joined time-nuts, having recently become interested in having a stable, accurate frequency reference available - mainly for amateur radio applications in the 1-24GHz region. Anyway, I have a Trimble Thunderbolt GPSDO, and a Lucent KS-24361 (REF 0 REF 1 units), and would like to have them both connected to the same antenna. I know that the KS-24361 puts out a dc feed on the TNC to power an active antenna, but am not sure whether the Thunderbolt does the same... So, can anyone who knows a little more about these two units recommend an antenna that will be suitable for both? Sorry if this is too basic a question for this list - I have had a look though a lot of the archive, but I can't seem to find the answer, and there doesn't appear to be a decent search facility :( Many thanks, in advance for any advice/ recommendations John Sent tomorrow, from my time machine. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Le 4 mai 2015 à 12:43, Chris Mottram c.mott...@ljmu.ac.uk a écrit : Hi Bob, I've just this minute joined this list, because I Tymserve 2100 unit we have at work has just started doing the same thing, at just gone 1am UT on May 3rd. I've also tried restarting and power cycling (this is somewhat convoluted as the unit is ~3000 miles away from me) but it's firmly stuck in 1995 Ours is currently running Rev 3.1 : 5 ? version Boot Code - Tymserve_2100 Rev 1.1 12/20/1996 13:07:21 Main Code - TymServe_2100 Rev 3.1 08/22/2002 12:15:37 After a power cycle, our unit comes up as follows: 3 ? time JAN 01 1995 00:01:53.687252 After the GPS has locked this changes to: 5 ? time SEP 17 1995 20:14:35.479915 Where 20:14 was the correct UT time.` The date is 7,169 Days -- or -- 1,024 Weeks and 1 Days » back, So that indicates it is due to GPS week rollover. There may be fixes from the manufacturer. Or you could correct in software before use. cheers Chris On 05/04/2015 12:31 AM, Bob Martin wrote: My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- - Chris Mottram | Liverpool Telescope Programmer.| Liverpool John Moores University, | email: c.mott...@ljmu.ac.uk Astrophysics Research Institute, | phone: (0151) 904 6591 IC2, Liverpool Science Park, | mobile: 07778650412 146 Brownlow Hill, Liverpool, L3 5RF | www: www.astro.ljmu.ac.uk -- C_Mottram.vcf___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. Ceux qui sont prêts à abandonner une liberté essentielle pour obtenir une petite et provisoire sécurité, ne méritent ni liberté ni sécurité. Benjimin Franklin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] ADEV with very short Tau
Thanks to you three for the answers. I don't have the skills to make a frequency mixer yet, but if I think a good tutorial, I can try ! My goal is to estimate the stability of a rubidium at 0.1s,1s and 10s. I have a GPSDO, some picDiv and one Pulse Generator. I believe the OCXO in the GPSDO (a HP 58530A) is better in stability than the Rubidium for shorts taus even if it has not a clear view of the sky (it doesn't see 6 satellites all the time) so I locked the 53131A counter to the GPSDO. I made some tests with TI measurements, see attached picture. In order to going to 0.1s, I generate 10 Hz on the pulse generator locked on the GPSDO (channel 1 of the counter) and feed the channel 2 with rubidium's 10 MHz. I get ADEV(0.1s) = 1.1 E-8 ADEV(1s) = 1.1 E-9 ADEV(10s) = 1.1 E-10 It's not wonderful, but I will be happy if I can measure 1E-9 at 0.1s. In fact, I think I measure the noise floor of the Pulse Generator. So I need to improve the setup. I manage to measure TI every 0.1s but when I want to measure frequency with Gate Time at 0.1s (with poor resolution I agree, but I will have access to a Frequency Difference Multiplier soon) it seems there is gaps in the records : for example,TI record gives with 10 Hz on channel 1: 1430740210.00.0007515140 1430740210.10.0007515140 1430740210.50.0007515140 1430740210.60.0007515125 1430740210.70.0007515150 1430740210.80.0007515140 1430740210.90.0007515135 Frequency record with Gate Time 1 s gives: 1430741572.77 1000.000 1430741573.96 1000.001 1430741575.15 1000.001 1430741576.34 1000.000 1430741577.53 1000.001 1430741578.72 1000.001 1430741579.92 1000.001 1430741581.11 1000.000 Frequency record with Gate Time 0.1 s gives : 1430741673.61000.00 1430741673.89 1000.00 1430741674.18 1000.00 1430741674.47 1000.00 1430741674.77 1000.00 1430741675.06 1000.00 1430741675.35 1000.00 First colomn is timestamp of the computer, I disabled auto trigger on the counter. What are the gaps in the frequency records, are they Dead Time ? They look to be constant, about 0,2s even when the Gate Time is 10s. Are they a problem for ADEV calculation? Thanks Claude - Mail original - De: Charles Steinmetz csteinm...@yandex.com À: Discussion of precise time and frequency measurement time-nuts@febo.com Envoyé: Mercredi 29 Avril 2015 22:04:14 Objet: Re: [time-nuts] ADEV with very short Tau Claude wrote: I know how to measure ADEV with frequency method (using a 53131A counter) or time difference method (using 1 PPS of a GPSDO for example) but I would like to measure ADEV in the sub-second domain (from 0.1s to 1s for example). Do I need a Time Interval Analyzer, if so, an HP 5371A is ok for that ? Or there are simpliest method ? You may do better with a Phase Noise measurement, depending on what instruments you have available. Generally, we think of oscillator stability over times = 1 second in the time domain, as xDEV, and stability over times = 1 second (or so) (offsets = 1 Hz) in the frequency domain, as Phase Noise. Partly, this is because of the different kinds of phenomena we are concerned about on the two different scales, and partly because different measurement techniques are better suited to each of the two time scales. These limits are not absolute, particularly if you digitize signals at a high sample rate with high resolution and do the analysis in the digital domain. Fancy xDEV/PN analyzers, such as the Microsemi 5125A, can measure xDEV down to tau = 1 mS and PN below a 1mHz offset. (But sit down before you ask the price.) I usually measure xDEV down to 0.1 second, and PN at offsets = 1 Hz. Of course, to measure xDEV at 0.1 second, you need to take at least ten TI or frequency measurements per second with no dead time between measurements, and with good accuracy -- so you need an instrument with very high resolution at short gate times and fairly fast data throughput. For that, I use a Wavecrest DTS2075. Best regards, Charles ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
This is a known problem for old GPS receivers, refer to this URL: http://www.leapsecond.com/notes/gpswnro.htm to learn more or search the Internet with the words GPS week number rollover. On Mon, May 4, 2015 at 12:43 PM, Chris Mottram c.mott...@ljmu.ac.uk wrote: Hi Bob, I've just this minute joined this list, because I Tymserve 2100 unit we have at work has just started doing the same thing, at just gone 1am UT on May 3rd. I've also tried restarting and power cycling (this is somewhat convoluted as the unit is ~3000 miles away from me) but it's firmly stuck in 1995 Ours is currently running Rev 3.1 : 5 ? version Boot Code - Tymserve_2100 Rev 1.1 12/20/1996 13:07:21 Main Code - TymServe_2100 Rev 3.1 08/22/2002 12:15:37 After a power cycle, our unit comes up as follows: 3 ? time JAN 01 1995 00:01:53.687252 After the GPS has locked this changes to: 5 ? time SEP 17 1995 20:14:35.479915 Where 20:14 was the correct UT time. cheers Chris On 05/04/2015 12:31 AM, Bob Martin wrote: My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- - Chris Mottram | Liverpool Telescope Programmer.| Liverpool John Moores University, | email: c.mott...@ljmu.ac.uk Astrophysics Research Institute, | phone: (0151) 904 6591 IC2, Liverpool Science Park, | mobile: 07778650412 146 Brownlow Hill, Liverpool, L3 5RF | www: www.astro.ljmu.ac.uk -- ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
You probably need the firmware update: Boot Code - Tymserve_2100 Rev 1.1 12/20/1996 13:07:21 Main Code - TymServe_2100 Rev 4.1 12/01/2005 14:45:23 http://www.ko4bb.com/getsimple/index.php?id=downloadfile=01_ROM_Images_and_Drivers/DatumET-6000TS-2100.zip -Bob On 05/04/2015 05:43 AM, Chris Mottram wrote: Hi Bob, I've just this minute joined this list, because I Tymserve 2100 unit we have at work has just started doing the same thing, at just gone 1am UT on May 3rd. I've also tried restarting and power cycling (this is somewhat convoluted as the unit is ~3000 miles away from me) but it's firmly stuck in 1995 Ours is currently running Rev 3.1 : 5 ? version Boot Code - Tymserve_2100 Rev 1.1 12/20/1996 13:07:21 Main Code - TymServe_2100 Rev 3.1 08/22/2002 12:15:37 After a power cycle, our unit comes up as follows: 3 ? time JAN 01 1995 00:01:53.687252 After the GPS has locked this changes to: 5 ? time SEP 17 1995 20:14:35.479915 Where 20:14 was the correct UT time. cheers Chris On 05/04/2015 12:31 AM, Bob Martin wrote: My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
It's not you, it's the TS2100. I have the same issue. Looks like this may be the end of life for this unit unless Datum/Symmetricom creates a patch. I saw the issue start around May 2 21:05 EDT. The time shows 619315200 seconds behind: 619315200/60/60/24/7 = 1024 weeks. It did seem like the leap second issue was no longer a problem tho, the seconds were no longer mismatched. :-/ On Sun, May 03, 2015 at 04:31:01PM -0700, Bob Martin wrote: My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] TS2100 thinks it's 1995...
Middle of the night I had a worry this was a rollover bug... And that seems to be confirmed, 1024 weeks. As I mentioned in an electronic conversation with another TS2100 user, I have the feeling our TS2100s have turned into turnips. Well, I can use the 1U space in that rack... Don't recall what processor they use in the thing, but life is too short to go digging through decades old assembly code. I will miss the IRIG time display mounted above my main LCDs though. While the time is accurate (well, it's off a second due the TS2100 leap pending bug), the day of the year is off by a bit. --bob k6rtm ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361/Thunderbolt antenna advice sought.
I am using hp58516a distribution amplifier. Trimble active antenna, Trimble TB and BC637PCI constantly connected to that unit. And time to time I connecting some DUT and GPS modules to it. It works for me. Regards, V.P. On 2015-05-04 08:18, Oghma wrote: Hi, all I've only recently joined time-nuts, having recently become interested in having a stable, accurate frequency reference available - mainly for amateur radio applications in the 1-24GHz region. Anyway, I have a Trimble Thunderbolt GPSDO, and a Lucent KS-24361 (REF 0 REF 1 units), and would like to have them both connected to the same antenna. I know that the KS-24361 puts out a dc feed on the TNC to power an active antenna, but am not sure whether the Thunderbolt does the same... So, can anyone who knows a little more about these two units recommend an antenna that will be suitable for both? Sorry if this is too basic a question for this list - I have had a look though a lot of the archive, but I can't seem to find the answer, and there doesn't appear to be a decent search facility :( Many thanks, in advance for any advice/ recommendations John Sent tomorrow, from my time machine. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- WBW, V.P. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Hi, by any chance do your Tymserve 2100's havea 1pps input that they can use to receive a timing source in lieuof their own GPS once the date and time are set manually? I run my Datum badged Tymserve 2000 this way and other thanhaving to manually deal with leap seconds it has been working well sofar. (Prior posts have indicated that at least one of the users havingtroubles with their Tymserve 2100 has access to another GPS, and also indicatedthat the units would keep the correct date in free mode, so perhaps they couldbe clocked from an external GPS.) Essentially I use my Tymserve 2000 as a NTP serverthat is clocked by an external 1pps source from a GPSDO. I have no ideahow long it will keep running properly, but for a home lab it meets my needs. I wouldn't want to use this approach at work or for a critical applicationbut thought I would offer this a suggestion as a possible way to breathe a bitmore life into an older piece of equipment. Regards Mark Spencer ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Ultra High Stability Time Base Options for 53132A
Charles, Thanks for the help. I need to learn how to add text to .PDF documents. To change the focus a bit, I'm just getting to know the Morion variant but it seems very impressive so far. As a 'SEVERE' novice in the 'time-nuts' arena, if anyone is interested in helping me characterize the two time bases in the 53132A, I would love to try to make some useful/helpful measurements to try to characterize the 53132A's ability to do time/frequency measurements with the HP 010 option versus the Morion variant. I probably have the needed equipment to do the measurements but would love to get some 'tutoring' on how to make useful/helpful measurements. Thanks again. Joe -Original Message- From: Charles Steinmetz [mailto:csteinm...@yandex.com] Sent: Monday, May 04, 2015 11:00 AM To: Discussion of precise time and frequency measurement Cc: J. L. Trantham Subject: Re: [time-nuts] Ultra High Stability Time Base Options for 53132A Joe wrote: C2, C3, C4, and C5 on the HP 53132-60011 board * * * appear to be .01 uF SMT caps. These parts are not on the 53132-60016 board. * * * Charles Steinmetz has annotated the schematic of the 53132-60011 board to clarify some issues as well. Please add these values to your schematics. I'll see if I can make a modification to the schematic and upload the details to Didier's site. I am attaching a file with the capacitor values added. I have also uploaded it to Didier's site (filename is HP_53132-60011_Timebase_Support_Board_redrawn.pdf). Thanks, Joe, for your diligence! Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Yes, but it can be a bit difficult to find on some units. Our 2100's do not have a BNC 1PPS in, but you can put the signal on pins 6 and 8 of the GPS HD15 connector, 6 is signal, 8 is ground. Andrew -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mark Spencer Sent: Monday, May 04, 2015 2:33 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Tymserve 2100 thinks it's 1995? Hi, by any chance do your Tymserve 2100's havea 1pps input that they can use to receive a timing source in lieuof their own GPS once the date and time are set manually? I run my Datum badged Tymserve 2000 this way and other thanhaving to manually deal with leap seconds it has been working well sofar. (Prior posts have indicated that at least one of the users havingtroubles with their Tymserve 2100 has access to another GPS, and also indicatedthat the units would keep the correct date in free mode, so perhaps they couldbe clocked from an external GPS.) Essentially I use my Tymserve 2000 as a NTP serverthat is clocked by an external 1pps source from a GPSDO. I have no ideahow long it will keep running properly, but for a home lab it meets my needs. I wouldn't want to use this approach at work or for a critical applicationbut thought I would offer this a suggestion as a possible way to breathe a bitmore life into an older piece of equipment. Regards Mark Spencer ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] TymServe 2100 1995 Issue - A Kludgy Fix
We also ran into the TS2100 1995 bug this weekend. For us the consequences are a bit more severe... The telescopes will not point to the right location in the sky without accurate time! For now we have configured a temporary fix... We set up two units, previously our primary and hot spare. The first unit is set to use GPS, which of course has the correct time but the wrong date. The first unit is sending a 1PPS signal to a second unit which is set to 1PPS input mode with a manually set date and time. We now have all of the IRIG and NTP capability we need and the correct date. Yes, there is also an order in with purchasing for an S350 SyncServer unit. Andrew Andrew Cooper Electrical Engineer W. M. Keck Observatory 808-881-3862 mailto:acoo...@keck.hawaii.edu ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] OT: PDF editing (was: Re: Ultra High Stability Time Base Options for 53132A)
On 5/4/2015 5:25 PM, J. L. Trantham wrote: Charles, Thanks for the help. I need to learn how to add text to .PDF documents. Go to: www.tracker-software.com and download (for free): PDF-Xchange viewer. Rick Karlquist N6RK ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Hi Before we all wail and moan about Tymeserve not rolling out a fix consider: This is not exactly a brand new box. They already patched this issue once (a decade ago). There are some very big names in the business that cut non-security patch support at the 5 year point. The market for this stuff never was big and it’s getting smaller. Supporting never ending patches on a zero income product is tough. One of the main assets these companies have is their code base. The market may not be expanding. There’s always a chance to bundle the IP and sell it. The value of that IP goes to zero if you give it away. Development costs these days are 80% firmware / software. Most of the price you pay for a low volume gizmo like this is for IP. The (dirt cheap) silicon bits on the pc board don’t count much. The days of “hardware rules” are long gone. You can claim that software costs nothing once you write the first copy. In the next breath we all expect to get ongoing customer support for that software and (e ) patches for this and that. When a vendor charges us by the year for that support we are unhappy. Would I love to see all these 10 to 20 year old boxes running perfectly 20 years from now - sure. It’s a noble goal. I have a *lot* of boxes. With all the GPS issues in the past, and likely in the future - not likely to happen. Bob On May 4, 2015, at 2:23 PM, Mark Strovink mark.a.strov...@mdnt.com wrote: Bob Martin k6rtm@... writes: Additional information -- Power cycling (leaving it off for about 5 minutes) didn't do any good. Once at the correct time/date, it bounces back to 1995 at about 30 seconds after the hour (now to Sep 18, 1995). My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm What a great way to start a Monday: phone call that the entire domain was back in 1995. The good news: Tymserve units will keep the correct date in Free mode. GPS handling, not the GPS signail, is the problem. The GPS unit is rolling the date over to its initial date once the date is past May 2 or 3, 2015. The bad news: Tech support said the company will not be providing a fix for a product 5 years past end of support. ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Mine was fine until I power cycled it :( I can confirm that even with the v4.1 firmware, power cycling it causes the date to revert back to 1995. A software restart as listed below seems to restore the correct date for awhile but it eventually reverts back to the wrong year. Maybe some smart guy can reverse engineer the binary and patch it. It must have already been patched once by the vendor since it seems unlikely the GPS firmware would have been updated. Luckily I have an ET-6000 so I can always feed IRIG-B from it into the TS-2100 until it too exhibits the rollover bug. After that runs out, I can use the 1 PPS input. -Bob On 05/04/2015 01:23 PM, Mark Strovink wrote: Bob Martink6rtm@... writes: Additional information -- Power cycling (leaving it off for about 5 minutes) didn't do any good. Once at the correct time/date, it bounces back to 1995 at about 30 seconds after the hour (now to Sep 18, 1995). My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm What a great way to start a Monday: phone call that the entire domain was back in 1995. The good news: Tymserve units will keep the correct date in Free mode. GPS handling, not the GPS signail, is the problem. The GPS unit is rolling the date over to its initial date once the date is past May 2 or 3, 2015. The bad news: Tech support said the company will not be providing a fix for a product 5 years past end of support. ___ time-nuts mailing list --time-nuts@febo.com To unsubscribe, go tohttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361/Thunderbolt antenna advice sought.
On Mon, May 4, 2015 at 5:18 AM, Oghma og...@live.co.uk wrote: Hi, all I've only recently joined time-nuts, having recently become interested in having a stable, accurate frequency reference available - mainly for amateur radio applications in the 1-24GHz region. Anyway, I have a Trimble Thunderbolt GPSDO, and a Lucent KS-24361 (REF 0 REF 1 units), and would like to have them both connected to the same antenna. I know that the KS-24361 puts out a dc feed on the TNC to power an active antenna, but am not sure whether the Thunderbolt does the same... So, can anyone who knows a little more about these two units recommend an antenna that will be suitable for both? Almost all GPS receivers output DC power for the antenna. On some there is a way to disable this, many times by removing a jumper. What you need is an antenna splitter that blocks DC on one side and passes it on the other. Many splitters do this. A little surprisingly, an antenna splitter made for cable TV works. Many peoples a more expensive solution where the GPS antenna drives a distribution amplifier and then that drives the GPS receivers. Or they use specialized GPS bad antenna spitter's. I'd like the know if the more expensive methods really do perform measurably better. What I'd do is start with a cheap cable TV splitter that blocks DC on one side and then upgrade later if required. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lucent KS-24361/Thunderbolt antenna advice sought.
Hi Both units put out DC to the antenna. With them “dc coupled” to each other and the antenna, you may see “antenna open” (low current) warnings. There are multiple solutions ranging from using DC loaded couplers (HP/Symmetricom) or simply tacking a resistive load on a multi-port splitter (Mini-Circuits). If cost is an issue and you can find a 3 or 4 port 2 GHz satellite dish splitter, those also work. Bob On May 4, 2015, at 8:18 AM, Oghma og...@live.co.uk wrote: Hi, all I've only recently joined time-nuts, having recently become interested in having a stable, accurate frequency reference available - mainly for amateur radio applications in the 1-24GHz region. Anyway, I have a Trimble Thunderbolt GPSDO, and a Lucent KS-24361 (REF 0 REF 1 units), and would like to have them both connected to the same antenna. I know that the KS-24361 puts out a dc feed on the TNC to power an active antenna, but am not sure whether the Thunderbolt does the same... So, can anyone who knows a little more about these two units recommend an antenna that will be suitable for both? Sorry if this is too basic a question for this list - I have had a look though a lot of the archive, but I can't seem to find the answer, and there doesn't appear to be a decent search facility :( Many thanks, in advance for any advice/ recommendations John Sent tomorrow, from my time machine. ___ time-nuts mailing list -- time-nuts@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] time-nuts scraping
Hello Time-Nuts, If you have some technical expertise with the evolving web, please read this; otherwise ignore this off-topic post. Normally people enter time-nuts through the main Time-Nuts web page: http://leapsecond.com/time-nuts.htm And John Ackermann, N8UR, hosts this list at: https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts For 11 years now, the list is archived at: https://www.febo.com/pipermail/time-nuts/ This is why when you want to google for time-nuts topics it's useful to add site:febo.com to the list of search words. It turns out there are other copies of time-nuts postings on the web. Some of the members of time-nuts are not people at all but bots that scrape all content and then are re-hosted elsewhere. Among them are mail-archive.com, narkive.com, and gmane.org or perhaps others. If you have experience with any of these three scapers please let me know. It is not necessarily a bad thing. But I would be interested in your experience or your insights into this practice of taking mailing lists and re-publishing or marketing them. Secondly, over the past year we've seen an increase in the number of postings made by members through gmane.org. This goes beyond scaping and actually fakes the registration process and allows people to attempt to post to time-nuts without going through leapsecond.com or febo.com. Again this may not necessarily be a bad thing. But I would be interested in your insights into this trend. Or if you are one of these gmane users, how well does it work for you, and why did you choose this method in the first place? If you have any information, insights, or advice, please contact me off-list. I'm t...@leapsecond.com and would appreciate any comments. Thanks, /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Tymserve 2100 thinks it's 1995?
Bob Martin k6rtm@... writes: Additional information -- Power cycling (leaving it off for about 5 minutes) didn't do any good. Once at the correct time/date, it bounces back to 1995 at about 30 seconds after the hour (now to Sep 18, 1995). My Tymserve 2100 gps unit (Rev 4.1) thinks it's 1995 -- September 17, 1995. But a restart (connect via telnet and give the commands util restart) brings it back to the correct time and date -- for a while? I haven't caught it dropping back, so i don't know if it's doing this on the hour, after an hour, or what, but I noticed it last night, and I've restarted it a few times today. Any clues? I know about the off-by-a-second issue with the pending leap second. This one is more interesting! So far I've just been issuing software restarts. The next time I'll power cycle the sucker and see if that does any good. GPS signal isn't the issue; the 2100 shares an external GPS antenna with my Thunderbolts through a Symmetricom 58536A GPS splitter, and the Thunderbolts are as happy as a Thunderbolt can be. cheers bob k6rtm What a great way to start a Monday: phone call that the entire domain was back in 1995. The good news: Tymserve units will keep the correct date in Free mode. GPS handling, not the GPS signail, is the problem. The GPS unit is rolling the date over to its initial date once the date is past May 2 or 3, 2015. The bad news: Tech support said the company will not be providing a fix for a product 5 years past end of support. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS splitter (was antenna advice sought)
I have a 58535A splitter that was purchased on ebay in 2013 that was working fine when I stopped using in 2014. I'd like to give it to someone who has need of a reasonable two-way splitter. I.e. not simply for resale if you don't mind. It goes to the first requester -- off-list ONLY. You have to pay postage which is currently $12.65 for a Priority Mail(tm) Medium Flat Rate Box. Not only that but you have to send me a Priority Mail label and postage (or preferably an equivalent PDF if you're used to shipping via USPS) -- that is I don't want money. I'll provide the box. Naturally USA only. The Symmetricon/HP 58535A is an active GPS splitter with three male N connectors. Typical use is DC in on one of two ports, GPS in on one port GPS out on two ports. -- Paul ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
