GPSDO - Some Measurements

I've done some long term measurements on my GPSDO. The GPSDO has a RS232 based simple command interface.

Commandline interface

It has a bunch of commands available. I assume, that the following commands provide information on the GPSDO internal control loops for temperature and GPS.

Status command "diagnostics:loop?"

This command provides the following output:

UCCM-P > diagnostic:loop?
-------------------------------------------------------------------------------
9/1/2016 10:43:51
-------------------------------------------------------------------------------
LOS      MEAS       NCO STATUS WEIGHT PBUC FBUC DBUC LBUC IBUC G  M TC
-------------------------------------------------------------------------------
0:  1  0.000e+00  0.000e+00 0x07AC   0   700  700    0    0    0  2  4 29
1:  1  0.000e+00  0.000e+00 0x068C   0   700  700    0    0    0  2 14 226
GPS: 0  5.988e-08  6.357e-08 0x0000   1  ---- 1000 1000 ---- ----  3  6 31
-------------------------------------------------------------------------------
freq cor  = 6.356560e-08
phase cor = -2.000000e-11
gps phase = 1.366667e-08
temp cor  = -3.911350e-11

Using this command, I extract these values for "freq cor", "phase cor", "gps phase" and "temp cor" and feed it into my sensor network. Each diagram shows the data for the last 15days.

If someone has more information on the meaning of these value, please give me a hint!

Frequency correction

g1 At the beginning and at about day #5, you see a restart of the GPSDO due to power failure. This line is contantly rising - no idea why this happens. If someone has a clue, feel free to contact me!

Temperature correction

g2 This value is reverse proportional to the room temperature of the GPSDO. The warmer the room, the less the main osciallator has to be heated.

GPSPhase

g3 At the beginning and at about day 10 you see a restart of the GPSDO due to power failure. This value is more or less stable - means a horizontal line.

Phase correction

g4 This value is more or less stable - means a horizontal line.

 

GPS:SATellite:TRACking:COUNt?

UCCM-P > GPS:SATellite:TRACking:COUNt?
+4

 From this command, I extract the number of tracked satellites. g5 The diagram also shows the data for the last 15 days.

system:status?

UCCM-P > system:status?
-------------------------------------------------------------------------------
090-03861-03   serial number W561002488   firmware ver 1.0.0.2-01     LINK mode
-------------------------------------------------------------------------------
Reference Status __________________________   Reference Outputs _______________
   Ref 8KHz 0: [LOS]
                                              TFOM     2             FFOM     0
                                              UCCM-P Status[ACTIVE]
>> GPS: [phase:  5.00e-09]
ACQUISITION ................................................ [ GPS 1PPS Valid ]
Tracking: 4 ____   Not Tracking: 5 ________   Time ____________________________
PRN  El  Az  C/N   PRN  El  Az                GPS      10:46:26     01 SEP 2016
 18  38 131   40    10  17 165                GPS      Synchronized to UTC
 21  64  66   35    16  63 290                ANT DLY  +0.000E+00
 26  69 204   43    20  32  62                Position ________________________
 29  13  91   35    27  37 286                MODE     Hold
                    31   5 204
                                              LAT      N  48:xx:xx.xxx
                                              LON      E   9:xx:xx.xxx
                                              HGT              +xxx.30 m  (MSL)
ELEV MASK  5 deg
-------------------------------------------------------------------------------

 tbd