Motorola HT Series

Maintenance: Low Band Troubleshooting Charts 8-37
8.13.2 Troubleshooting Flow Chart for Receiver (Sheet 1 of 2)
Activity on
U303 sel pin?
Bad SINAD
Bad 20dB Quieting
No Recovered Audio
START
Audio at pin 27
of U303?
Check Controller
Ye s
No
Spray of inject 1st IF into
XTAL Filter
IF Freq: 109.65 MHz
Audio heard?
B
Ye s
No
Check 2nd LO Control
Voltage at C308
VCO locked?
B
Ye s
17.0 MHz
check at pin 22
U303?
Check FGU
No
No
A
A
Ye s
Check Q301 bias cir-
cuitry for faults.
Rotate Freq. Knob
Check controller.
Before replacing U303, check 2nd VCO
Q301. Check VCO O/P level, C315,
C316
Ye s
No