Troubleshooting Flow Chart For Vco - Motorola Pro Series Elite Service Manual

VHF Troubleshooting Charts
No
Check R3811, L3811 for dry
joint or faulty

Troubleshooting Flow Chart for VCO

Change U3801
No
Yes
L3831, L3832,
L3833 O/C?
Yes
Yes
Pin 10 >1V?
Check U3701 Pin 2
A
Yes
Pin 19 =0V
Check for faulty parts or dry joints of
No
L3812 C3806, R3806, R3802 & L3801
AUX 3 Low?
No
Yes
Change U3801
Change L3831,
L3832
No
TRB = 3.2V?
No
Yes
AUX 3 High?
No
for 3.2V
V ctrl 0V or
13V?
Yes
No
Change U3701
START
No LO?
No
Tx Carrier?
Yes
VCO OK
Check R3829
Change L3821,
L3822, L382,
L243
Yes
L3821, L3822,
L3823 Open Cir-
No
cuit?
3-15
Yes
A
Change U3801