
UHF Troubleshooting Charts
3-11
Troubleshooting Flow Chart for Transmitter
START
No Power
Is There
B+ Bias for
Ant switch
CR101
Check Q111
Is Current
OK?
Is Control Voltage
High or Low at
C119
Check PCIC
1. Check Pin Diodes
2. Check Harmonic Filter
Inspect/Repair Tx.
Output Network
Is Power
OK?
Done
Check Drive to
Module
Is Drive
OK?
Troubleshoot
VCO
Inspect PA Network/
Check Power Out of
U101 at Cap C160
Is Power
OK?
Replace U101
Is Power
OK?
Replace Q110
Done
Done
No
Yes
Yes
No
No
Yes
Low
High
No
Yes
Yes
No
Yes
No