OPERATOR
ERROR AND WARNING/
MAINTENANCE
STATUS MESSAGES
Error Message
Description/Remarks
Error 126
2 – 8.4 GHz Unlocked and
Unleveled
Indicates a failure of the 2 to 8.4 GHz YIG-tuned oscillator. Do Not Attempt to
Operate! Refer the instrument to a qualified service techician.
Error 127
Detector Input Circuit
Failed
Indicates a failure of the level detector input circuitry on the A10 PCB. Use caution
and always determine the output power level when operating the 681XXB in this
condition.
Error 128
.01 – 2 GHz Unleveled
Indicates a failure of the Down Converter leveling circuitry. The 681XXB operates
normally but will have unleveled RF output in the 0.01 - 2 GHz frequency range.
Error 129
Switched Filter or Level
Detector Failed
Indicates a failure of either the switched filter or level detector circuitry. The
681XXB may or may not produce an RF output. Use caution and always determine
the output power level when operating the 681XXB in this condition.
Error 130
2 – 3.3 GH Switched Filter
Indicates a failure in the 2 - 3.3 GHz switched filter path within the switched filter
assembly. The 681XXB may or may not produce an RF output in this frequency
range. Use caution and always determine the output power level when operating
the 681XXB in this condition.
Error 131
3.3 – 5.5 GH Switched Filter
Indicates a failure in the 3.3 - 5.5 GHz switched filter path within the switched filter
assembly. The 681XXB may or may not produce an RF output in this frequency
range. Use caution and always determine the output power level when operating
the 681XXB in this condition.
Error 132
5.5 – 8.4 GH Switched Filter
Indicates a failure in the 5.5 - 8.4 GHz switched filter path within the switched filter
assembly. The 681XXB may or may not produce an RF output in this frequency
range. Use caution and always determine the output power level when operating
the 681XXB in this condition.
Error 133
8.4 – 13.25 GH Switched Filter
Indicates a failure in the 8.4 - 13.25 GHz switched filter path within the switched
filter assembly. The 681XXB may or may not produce an RF output in this
frequency range. Use caution and always determine the output power level when
operating the 681XXB in this condition.
Error 134
13.25 – 20 GH Switched Filter
Indicates a failure in the 13.25 - 20 GHz switched filter path within the switched
filter assembly. The 681XXB may or may not produce an RF output in this
frequency range. Use caution and always determine the output power level when
operating the 681XXB in this condition.
Error 135
Modulator or Driver Failed
Indicates a failure of the modulator in the switched filter assembly or the modulator
driver circuitry on the A9 PCB. The 681XXB may or may not produce an RF output.
Use caution and always determine the output power level when operating the
681XXB in this condition.
Error 138
SDM Unit or Driver Failed
Indicates a failure of the switched doubler module (SDM) or SDM bias regulator
circuitry on the A14 PCB. The 681XXB is still operable but it will not produce an RF
output in the 20 - 40 GHz frequency range.
Table 6-1.
Self-Test Error Messages (3 of 4)
6-6
681XXB OM
Changed: November 1995