Troubleshooting Flow Chart For Vco - Motorola HT Series Detailed Service Manual

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3.6

Troubleshooting Flow Chart for VCO

L253 O/C?
No
Pin 10
Check R245 for dry
joint or faulty
December 26, 2003
UHF Troubleshooting Charts: Troubleshooting Flow Chart for VCO
Change
U241
No
Yes
Change
L253
Yes
Yes
TRB = 5V?
>1V?
AUX 3
High?
Check U201
Pin 2 for 3.2V
A
Yes
Pin 19
=0V
Check for faulty parts or dry
No
joints of L271, L273, C370,
C386, R339 & L320
AUX 4
High?
No
Yes
Change
Q261
No
Tx Carrier?
No
VCO OK
Check
R260
No
Change
V ctrl 0V
Yes
or 13V?
L243 Open
Circuit?
No
Change
U201
START
Yes
No LO?
A
No
Yes
L243
Yes
No
Change
U241
FMR-2045A-2