682XXB/683XXB MM 5-41Output Power Level Related Problems(0.01 to 20 GHz)
Error 128 .01-2 GHz Unleveled
Description: Error 128 indicates a failure of of the down converter
leveling circuitry.The 682XXB/683XXB may or may not produce an RF
output in the 0.01 to 2 GHz frequency range. Thus, there are two trou-
bleshooting 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: 2.000 GHz
Number of Steps: 400
L1: +1.00 dBm
683XXB Setup:
CW/SWEEP SELECT:Analog
F1: 0.010 GHz
F2: 2.000 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 down converter.
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 (1 of 8)
TROUBLESHOOTING
TROUBLESHOOTING TABLES