Re: [time-nuts] 58503A does not track
- Mail original - > De: "Mike Cook" > À: "Discussion of precise time and frequency measurement" > Envoyé: Jeudi 28 Janvier 2016 11:21:45 > Objet: Re: [time-nuts] 58503A does not track > > > > Le 28 janv. 2016 à 07:37, claude...@aliceadsl.fr a écrit : > > > > Thanks for your reply > > > > I don't think it's a computer problem because I can see the GPS is > > not locked when I compare the 10 MHz output with a Rubidium. > > By the way, I don't use software but the screen command under > > Linux. > > > > Maybe the motorola bord is dead, I will investigate this : I have > > to send commands directly to the board, as suggested by someone > > offlist. > > > > > > The board in the GPSDO is a Motorola 84D43579M03 . The same as this > > one : > > http://www.ebay.com/itm/HP-Z3801A-Z3805A-GPS-Module-Motorola-Oncore-P-N-84D43579M03-/161594138402?nma=true&si=jnWr5n2KQf1WL6JylF%252BMgtIr1%252FM%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557 > > > > > > Do you think it can be replaced by this one : > > http://www.ebay.com/itm/Z3801A-Z3805A-GPS-Receiver-VP-oncore-B4121Z1116-/281670591394?hash=item4194e023a2 > > > > > > I think you can replace your receiver with this. Some Z3801As ( which > are pretty much the Telco versions of the 58503A) came with the > 84D43579M03 part , but mine has a B412P1115 . I think you should be > safe with the replacement. I have a Motorola document which says > that the B parts with firmware 8.1 and later have "8 channel code > added" with some related commands, so I guess your part is a 6 > channel model. In a command reference manual from Synergy Systems, > Randy Warner states > > “house numbered” receivers with total jibberish for model numbers > have worked their way into the surplus market, but under the skin > they are probably pretty standard parts. “If it walks like a VP, > talks like a VP, and acts like a VP, it’s probably some variation of > a VP.” > > I can’t see any indication in the command guide that 8 channel > receivers will not accept the 6 channel command set however that > might be an issue at set up . > > My advice is suck it and see. The VP above is cheap enough . I am > going to order one if I can get a shipping price to France and there > are any left. > > Hello, A little follow-up : I've bougth the card in the link above and it works perfectly with my 58503A. Thanks to you both for the advices. Claude ___ 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] 58503A does not track
Thanks for your reply I don't think it's a computer problem because I can see the GPS is not locked when I compare the 10 MHz output with a Rubidium. By the way, I don't use software but the screen command under Linux. Maybe the motorola bord is dead, I will investigate this : I have to send commands directly to the board, as suggested by someone offlist. The board in the GPSDO is a Motorola 84D43579M03 . The same as this one : http://www.ebay.com/itm/HP-Z3801A-Z3805A-GPS-Module-Motorola-Oncore-P-N-84D43579M03-/161594138402?nma=true&si=jnWr5n2KQf1WL6JylF%252BMgtIr1%252FM%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557 Do you think it can be replaced by this one : http://www.ebay.com/itm/Z3801A-Z3805A-GPS-Receiver-VP-oncore-B4121Z1116-/281670591394?hash=item4194e023a2 Thanks Claude - Mail original - De: "Artek Manuals" À: "Discussion of precise time and frequency measurement" Envoyé: Jeudi 28 Janvier 2016 00:27:43 Objet: Re: [time-nuts] 58503A does not track Claude Are you using the same software on the same computer platform for the whole time? By example I have a Z3801 which works sometimes under Z38xx and sometimes not, while SATSTAT works all the time. I did find some flaky things going on with the software and was finding that I had to close Z38xx and reopen it after every command to change something? Dave On 1/26/2016 11:39 AM, claude...@aliceadsl.fr wrote: > Hello list ! > > I have a HP 58503A who worked fine for two years. > After a short power cut, it does not lock on GPS. I tried some commandsn > including :SYST:PRESET but nothing works > > Here's a :SYSTEM:STATUS ? after the PRESET and after waiting a few hours : > > > --- Receiver Status > --- > > SYNCHRONIZATION ... [ Outputs Invalid > ] > SmartClock Mode ___ Reference Outputs > ___ > Locked TFOM 9 FFOM > 3 > Recovery 1PPS TI -- > Holdover HOLD THR 1.000 us >>> Power-up: GPS acquisition Holdover Uncertainty >Predict -- > > ACQUISITION .. [ GPS 1PPS Invalid > ] > Tracking: 0 Not Tracking: 6 Time > > PRN El AzUTC 16:06:43 [?] 29 Feb > 2016 > * 1 -- ---GPS 1PPS Invalid: not tracking > * 6 -- ---ANT DLY 0 ns > * 9 -- ---Position > > *14 -- ---MODE Survey: 0% > complete > *22 -- --- Suspended: track <4 > sats > *24 -- ---INIT LAT N 596:30:43.423 >INIT LON E 596:31:10.845 > ELEV MASK 10 deg *attempting to track +21474708.00 m > (MSL) > HEALTH MONITOR . [ OK > ] > Self Test: OKInt Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK > > I tried to set the date with :GPS:INIT:DATE 2016,01,26 but this command has > no effect. > > Setting the LAT and LON with :GPS:POS «myposition» works. > > --- Receiver Status > --- > > SYNCHRONIZATION ... [ Outputs Invalid > ] > SmartClock Mode ___ Reference Outputs > ___ > Locked TFOM 9 FFOM > 3 > Recovery 1PPS TI -- > Holdover HOLD THR 1.000 us >>> Power-up: GPS acquisition Holdover Uncertainty >Predict -- > > ACQUISITION .. [ GPS 1PPS Invalid > ] > Tracking: 0 Not Tracking: 6 Time > > PRN El AzUTC 02:58:13 [?] 24 Mar > 2016 > * 3 -- ---GPS 1PPS Invalid: not tracking > * 4 -- ---ANT DLY 0 ns > * 8 -- ---Position > > * 9 -- ---MODE Hold > *23 -- --- > *29 -- ---LAT Nblah blah >LON Eblah blah > ELEV MASK 10 deg *attempting to track HGT +194.57 m
[time-nuts] 58503A does not track
Hello list ! I have a HP 58503A who worked fine for two years. After a short power cut, it does not lock on GPS. I tried some commandsn including :SYST:PRESET but nothing works Here's a :SYSTEM:STATUS ? after the PRESET and after waiting a few hours : --- Receiver Status --- SYNCHRONIZATION ... [ Outputs Invalid ] SmartClock Mode ___ Reference Outputs ___ Locked TFOM 9 FFOM 3 Recovery 1PPS TI -- Holdover HOLD THR 1.000 us >> Power-up: GPS acquisition Holdover Uncertainty Predict -- ACQUISITION .. [ GPS 1PPS Invalid ] Tracking: 0 Not Tracking: 6 Time PRN El AzUTC 16:06:43 [?] 29 Feb 2016 * 1 -- ---GPS 1PPS Invalid: not tracking * 6 -- ---ANT DLY 0 ns * 9 -- ---Position *14 -- ---MODE Survey: 0% complete *22 -- --- Suspended: track <4 sats *24 -- ---INIT LAT N 596:30:43.423 INIT LON E 596:31:10.845 ELEV MASK 10 deg *attempting to track +21474708.00 m (MSL) HEALTH MONITOR . [ OK ] Self Test: OKInt Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK I tried to set the date with :GPS:INIT:DATE 2016,01,26 but this command has no effect. Setting the LAT and LON with :GPS:POS «myposition» works. --- Receiver Status --- SYNCHRONIZATION ... [ Outputs Invalid ] SmartClock Mode ___ Reference Outputs ___ Locked TFOM 9 FFOM 3 Recovery 1PPS TI -- Holdover HOLD THR 1.000 us >> Power-up: GPS acquisition Holdover Uncertainty Predict -- ACQUISITION .. [ GPS 1PPS Invalid ] Tracking: 0 Not Tracking: 6 Time PRN El AzUTC 02:58:13 [?] 24 Mar 2016 * 3 -- ---GPS 1PPS Invalid: not tracking * 4 -- ---ANT DLY 0 ns * 8 -- ---Position * 9 -- ---MODE Hold *23 -- --- *29 -- ---LAT Nblah blah LON Eblah blah ELEV MASK 10 deg *attempting to track HGT +194.57 m (MSL) HEALTH MONITOR . [ OK ] Self Test: OKInt Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK But the unit is still not tracking, it sees the birds because the PRN are changing but does not calculate the "El" and "Az" ... Here is the output of :DIAGnostic:LOG:READ:ALL? Log 001:20160122.00:00:00: Log cleared Log 002:20160122.00:00:00: System preset Log 003:20160122.00:00:35: Self-test failed Log 004:20160122.00:12:38: Position hold mode started As you can see, the date is 2016-01-22, it's the date when the power cut happened . And when I run :GPSYSTEM:POSITION:SURVEY ONCE, I get the same first status with crazy lattidude and longitude. Finally a self test *TST? gives +0 and the ALARM LED and the LOCK LED are off. I've tried with a second antenna and have the same problem :-( Can someone give me an advice for this problem ? The receiver looks dead, no ? Thanks in advance, Claude ___ 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" À: "Discussion of precise time and frequency measurement" 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.
[time-nuts] ADEV with very short Tau
Hello 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 ? Thanks for your advices. Claude ___ 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.
