Sample output shows a "dying" GPS receiver. For the two days before it failed completely, the receiver data did not indicate msec clock offsets (shown by the fact that there are no "-" or "+" indicators in the Clk plot line) as there should have been for a receiver of this type. The qc mode of teqc was used to detect clock offsets using the jumps in the pseudorange indicated with a "C" symbol in the plot, so that the file could then be processed. The "*" symbol used for most of the data indicates that AS was off and the observables L1, L2, P1, and P2 were being collected by the receiver for most epochs.

 SV+------------------------------------------------------------------------+ SV
  4|*C--__                                                  __M*************|  4
  5|*C***C*-__         ___-------__                                  _-M****|  5
 24|*C***C**--__                                                __M*********| 24
 20|*C***C***--__       __-M***C****--__                                  _-| 20
 16|*C***C****C-__                                                    __M***| 16
  6|-I***C****C****C*-__              _____                                 |  6
 26|_--**C****C****C*--_                                  ___----____       | 26
 17| ___--****C****C**C***C*--_                                             | 17
 23|    _---**C****C**C***C****C*-__                                        | 23
  9|__      ___--**C**C***C--_                                  __-M********|  9
 21|         __---*C**C***C****C*****--_                                    | 21
  1|            __-C**C***C****C*******---__                                |  1
 28|            __-m**C**----__       ___-M*******C***--_                   | 28
 25|                   _--C****C************--__                            | 25
 15|                       __-*C******---___      ___-M**********--_        | 15
 22|        _____              __-****************C__                       | 22
 14|                             _-M*************--__         __--M**---__  | 14
 29|                               ___-I**********C*****-__                 | 29
 18|__                                  __--I*****C********-__            __| 18
 31|                 __________           _-m*****C********--_              | 31
 19|                                       __--***C**********------_        | 19
 27|                                            __--****************--_     | 27
  2|                                             __---********************-_|  2
  7|-_                                                _-m*******************|  7
 12|            _________                                 __--*******IIM****| 12
-dn|  1   1  1 11         121111      111    1    1 11 1    1 22121   1     |-dn
+dn|122 111212122121 21 11333311121111222211121  12112121  12232234112231 11|+dn
+10|677678887766668888767799987777777776666778777777788987777788889888888888|+10
Pos|oo   o         o                                                        |Pos
Clk|                                                                        |Clk
   +------|--------|---------|--------|--------|---------|--------|---------+
01:01:30.000                                                        23:59:30.000
1995 Oct 16                                                          1995 Oct 16
 
******************
QC of obs file(s) : namc2890.95o
QC of nav file(s) : namc2890.95n
******************
 
Time of start of window : 1995 Oct 16  01:01:30.000
Time of  end  of window : 1995 Oct 16  23:59:30.000
Time line window length : 22.97 hour(s), ticked every 3.0 hour(s)
  antenna WGS 84 (xyz)  : 323649.4814 5639808.2597 2958762.2040 (m)
  antenna WGS 84 (geo)  : N  27 deg 48' 07.60"  E  86 deg 42' 56.13"
          WGS 84 height : 3510.6484 m
Observation interval    : 30.0000 seconds
Total satellites w/ obs : 25
NAVSTAR GPS SVs w/o OBS :  3  8 10 11 13 30 32
NAVSTAR GPS SVs w/o NAV :
Rx tracking capability  : 12 SVs
Poss. # of obs epochs   :   2757
Epochs w/ observations  :   2757
Possible obs > -0.00 deg:  24725
Possible obs > 10.00 deg:  19306
Complete obs > 10.00 deg:  16727
 Deleted obs > 10.00 deg:      4
Moving average MP1      : 0.172582 m
Moving average MP2      : 0.156661 m
Points in MP moving avg : 50
No. of Rx clock offsets : 0
Total Rx clock drift    :  0.000000 ms
Rate of Rx clock drift  :  0.000 ms/hr
Report gap > than       : 10.00 minute(s)
epochs w/ msec clk slip : 8
other msec mp events    : 3 (: 134)   {expect <= 1:50}
IOD signifying a slip   : >400.0 cm/minute
IOD slips < 10.00 deg   :      0
IOD slips > 10.00 deg   :      5
IOD | MP slips < 10.00  :      0
IOD | MP slips > 10.00  :     67
      first epoch    last epoch    hrs   dt  #expt  #have   %   mp1   mp2 o/slps
SUM 95 10 16 01:01 95 10 16 23:59 22.97  30  19306  16727  87  0.17  0.16    250
 
QC Symbol codes for ASCII plot:
 
Symbol codes for "SV":
(hierarchy is left-to-right, top-to_bottom)
C  receiver clock slip                m  n-msec multipath jump
I  ionospheric phase slip             M  multipath MP1 and MP2 slips
1  multipath MP1 slip only            2  multipath MP2 slip only
-  data gap of > 10.0 minutes         -  SV above elev mask, but no data
+  SV data, but below elev mask       ^  partial SV data and below elev mask
.  A/S off; L1 C/A                    :  A/S off; L1 P1
~  A/S off; L1 C/A L2 P2              *  A/S off; L1 P1 L2 P2
,  A/S on; L1 C/A                     ;  A/S on; L1 P1
o  A/S on; L1 C/A L2 P2               y  A/S on; L1 P1 L2 P2
L  Bit 0 of LLI set (rx lost lock)    _  no SV data and below elev mask
 
Symbol codes for "Pos" (position):
(hierarchy is left-to-right, top-to_bottom)
^  large position change              X  code position inverse failed
C  position did not converge          H  large horizontal uncertainty
V  large vertical uncertainty         T  large total uncertainty
>  kinematic survey is OK             o  static survey is OK
O  insufficient observables           E  insufficient ephemerides
S  insufficient SV set
 
Symbol codes for "Clk" (receiver clock):
(hierarchy is left-to-right, top-to_bottom)
-  reset by - msec                    +  reset by + msec

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