Technical data

8-8 Chapter 8
Receiver Troubleshooting
Check the 4 MHz REF Signal
Check the 4 MHz REF Signal
1. Connect a cable from the RF OUT port to input R.
2. Press .
3. Use an oscilloscope to observe the 4 MHz reference signal at A10P2-6.
• If the signal does not resemble Figure 8-3, troubleshoot the signal source (A12P2-36)
and path.
• If the signal is good, the probability is greater than 90% that the A10 assembly is
faulty. For confirmation, perform “Check A10 by Substitution or Signal
Examination,” next.
Figure 8-3 4 MHz REF Waveform
Preset