5-26 682XXB/683XXB MM–43VT Supply Problems
This supply provides –43 volts to drive the YIG-tuned oscillator main
tuning coil during bandswitching, fast analog sweeps, and digital
sweeps.
Step 9. Perform the following procedure to isolate malfunctions to
the –43VT supply and its outlying load circuit.
a. Place the LINE switch to STANDBY.
b. Replace the A15 PCB assembly.
c. Place the LINE switch to OPERATE.
d. Set up the 682XXB/683XXB to performa2to20GHz
step sweep.
e. Measure the –43VT voltage per Table 5-7.
If the voltage is correct, the problem is cleared.
If the voltage is incorrect, go to step f.
f. Place the LINE switch to STANDBY.
g. Remove the A13 PCB and the YIG-tuned oscillator
assembly.
h. Placethe LINE switch to OPERATE and measure the
–43VT voltage.
If the voltage is correct, go to step i.
If the voltage is still incorrect, contact your local
ANRITSU service center for assistance.
i. Place the LINE switch to STANDBY.
j. Installthe A13 PCB.
k. Placethe LINE switch to OPERATE and measure the
–43VT voltage.
If the voltage is correct, replace the YIG-tuned
oscillator assembly.
If the voltage is incorrect, replace the A13 PCB.
Table5-6. Error Messages 105 and 106 (8 of 10)
TROUBLESHOOTING
TROUBLESHOOTING TABLES