Motorola HT Series

Maintenance: Low Band Troubleshooting Charts 8-41
8.13.6 Troubleshooting Flow Chart for VCO
Level >
+2 dBm
Check signal at
collector of Q201
No
Ye s
Check L204, L211, L212,
L215, C221, C228, C229,
C230,C231, C235,C297,
R204, R234, R238
Check signal at
collector of Q201
No RX LO or No sig-
nal at U205 Pin 32 in
RX
No TX LO or No sig-
nal at U205 Pin 32 in
TX
Level >
+10 dBm?
Check signal at
drain of Q203
Level >
-3 dBm?
Check signal at
drain of Q202 and
Q204
Level >
+7 dBm?
No
Ye s
Replace Q201
Ye s
Ye s
Done
Check DC voltage
across R203
Problem
fixed?
Replace Q203
Check C215, C216,
L207, L208, L209,
U203
Level >
500 mV?
Check C200, C202, C203,
C222, C223, L201, L203,
TR201, CR202
Replace Q202
and Q204
Ye s
Ye s
No
No
NoNo