[time-nuts] 58503A does not track

[claude.ff at aliceadsl.fr]

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  Az                UTC      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: OK    Int 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  Az                UTC      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      N    blah blah
                                              LON      E    blah blah
ELEV MASK 10 deg   *attempting to track       HGT              +194.57 m  (MSL)
HEALTH MONITOR ......................................................... [ OK ]
Self Test: OK    Int 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