5-44 682XXB/683XXB MM
Error 129 Switched Filter or Level Detector Failed
Description: Error 129 indicates a failure of either the switched filter
or level detector circuitry.The 682XXB/683XXB may or may not pro-
duce an RF output in the 2 to 20 GHz frequency range. Thus, there are
two troubleshooting paths for this problem—unleveled with output
power and unleveled with no/low output power.
Unleveled with output power (The warning message UNLEVELED
appears on the front panel display):
Step 1. Set up the 682XXB/683XXB as follows:
a. 682XXB Setup:
CW/SWEEP SELECT:Step
F1: 0.010 GHz
F2: 20.000 GHz
Number of Steps: 400
L1: +1.00 dBm
683XXB Setup:
CW/SWEEP SELECT:Analog
F1: 0.010 GHz
F2: 20.000 GHz
Sweep Time: 0.100 Sec
L1: +1.00 dBm
b. LEVEL/ALC SELECT:ALC Mode
ALC Mode: Ext ALC Front
Leveling Menu: External Detector
Step 2. Connect a detector to the 682XXB/683XXB RF OUTPUT con-
nector and connect the detected DC output of the detector to
the front panel EXTERNALALC IN connector.
If the warning message UNLEVELED no longer appears
on the front panel display,replace the directional coupler.
If the warning message UNLEVELED is still displayed,
replace the A10 PCB.
Table5-20. Error Messages 128, 129, 130, 131, 132, 133, 134, and 135 (4 of 8)
TROUBLESHOOTING
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