On 1 Apr 2015 23:24, "Bob Camp" <kb...@n1k.org> wrote: > > HI > > Best guess is that your antenna is not doing the job.
That's possible. It was supposed to be an Andrews antenna, but there's nothing on it to indicate that to me. But it is well sited. I expect antenna issues can explain the log entry 092:20150330.19:30:37: Holdover started, not tracking GPS > If the HP is in lock long enough to predict a good holdover (there are multiple limits) you can have > holdover with no alarm. Which is what I did have with the above log entry. Log 103:20150331.00:00:00: Power on Log 104:20150331.00:08:19: GPS reference valid at 20150331.15:02:08 Log 105:20150331.15:03:16: GPS lock started Log 106:20150331.17:01:37: Position hold mode started > If it goes into holdover and is not “ok” by the various limits, you will get an > alarm + holdover. But I have never seen that. > After being in holdover for a while (how long depends) you will get an alarm. Likely > values are in the 24 hour range if it’s been on for a while. But that never happened. I got an email from someone else, who also has an 58503A, and says his recently showed "Alarm", with nothing in the log. He postulated whether it could be to do with the upcoming leap second, although I would have thought that on such an old design, if such issues existed, they would have been discovered before now. I just checked the receiver a minute or two ago, and the Alarm LED was on, as it has been for a few days now. I then sent E-113> *CLS scpi > :SYSTEM:STATUS? over the RS-232 and the LED went out. I want not expecting this, so can't say whether the *CLS or the :SYSTEM:STATUS? caused it to go out. (I would guess the first, but I don't know). I note the display now shows the pending leapsecond, which it did *not* when I posted this on April the 1st. When would the clock be expected to know about the leapsecond? Somewhere between the 8:59:42 on 1st April 2015 and 16:32:49 on the 4th April 2015, the receiver seems to have learned about the leapsecond, which will be added at the end of June. See below, for what it shows now. The 9.2 us/initial 24 hrs is a lot worst than it was a few days ago (4.9 us/initial 24 hrs), but 4.9 was unusually low. I have never seen it that low before, but I don't keep watching this thing all the time. I bought it mainly for a lab reference. scpi > :SYSTEM:STATUS? ------------------------------- Receiver Status ------------------------------- SYNCHRONIZATION ............................................. [ Outputs Valid ] SmartClock Mode ___________________________ Reference Outputs _______________ >> Locked to GPS TFOM 3 FFOM 0 Recovery 1PPS TI -11.8 ns relative to GPS Holdover HOLD THR 1.000 us Power-up Holdover Uncertainty ____________ Predict 9.2 us/initial 24 hrs ACQUISITION ................................................ [ GPS 1PPS Valid ] Tracking: 6 ____ Not Tracking: 1 ________ Time _____ +1 leap second pending PRN El Az SS PRN El Az UTC 15:32:49 04 Apr 2015 12 70 233 88 22 14 276 GPS 1PPS Synchronized to UTC 14 29 310 39 ANT DLY 0 ns 15 20 171 39 Position ________________________ 17 23 43 49 MODE Hold 24 76 108 71 25 30 239 33 LAT N 51:39:04.143 LON E 0:46:36.402 ELEV MASK 10 deg HGT +47.15 m (MSL) HEALTH MONITOR ......................................................... [ OK ] Self Test: OK Int Pwr: OK Oven Pwr: OK OCXO: OK EFC: OK GPS Rcv: OK scpi > :DIAG:LOG:READ:ALL? Log status: 106 entries <same as posted before - there are no new entries> Dave _______________________________________________ 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.