Anritsu 682XXB - Manual (Page 206)

5-40 682XXB/683XXB MM
G If the RF signal is correct in both frequency and ampli-
tude throughout the full sweep, go to step 8.
G If there is no RF signal for all or part of the sweep or if
the amplitude of the RF signal is low, go to step 5.
Step 5. Connect the X input of an oscilloscope to the 682XXB/
683XXB rear panel
HORIZ OUT connector.
Step 6. Using the oscilloscope, check for a –0.2 to –3.5 volt YIG
tuning ramp at A13TP10.
G If the ramp signal is correct, go to step 7.
G If the ramp signal is incorrect or not present, replace the
A13 PCB.
Step 7. Using the oscilloscope, check for the YIG bias voltages at the
test points shown in Table 5-19.
G If the YIG bias voltages are correct, replace the YIG-
tuned oscillator assembly.
G If the YIG bias voltages are incorrect, replace the A13
PCB.
Step 8. Run self-test again.
G If no error message is displayed, the problem is cleared.
G If any of the error messages, listed above, are displayed,
contact your local
ANRITSU service center for assistance.
Table 5-18. Error Messages 124, 125, and 126 (2 of 2)
TROUBLESHOOTING
TROUBLESHOOTING TABLES
Test Point
YIG-tuned Oscillator Bias Voltages
2 to 8.4 GHz 8.4 to 20 GHz
A13TP3 +6V +6V
A13TP5 0V +8V
A13TP6 –5V –5V
A13TP7 +8V 0V
Table 5-19. YIG-tuned Oscillator Bias Voltages