Motorola GP series Service Manual

Troubleshooting Flow Chart for Transmitter 3-3
3.0 Troubleshooting Flow Chart for Transmitter
Is
the fuse F501
OK?
Is
there a
short circuit
after C113
?
Is
overall radio
current between
0.8 and 1.3 A when
transmitting
?
Is
the voltage
at pin 4 of U102
between 2V and
5.6V
?
Is
the voltage
at pin 32 of U102
between 6V and
9V?
START
No Power out
or Low Power
Yes
Yes
Check L101, L102,
C101, CR101 for
open circuit
Find and remove
short circuit from
antenna switch or
harmonic filter
Low Power
Yes
Replace F501
Yes
Yes
Yes
Replace
U102
No
No
No
Is
the voltage
at R105 and C116
between 1.8V and
2.2V?
Is
the voltage
at pins 6, 5, 8, 9 of
U101 between 5.5V
and 7.5V
?
Yes
Troubleshoot
VCO
Replace
U101
Replace
Q101
No
No
No Power
No
No
Yes
No
Is
the voltage
at pin 24 of U102
between 2V and 5V
for High Power, 0V for
Low Power
?

Motorola GP series Specifications

General

Brand	Motorola
Model	GP series
Category	Radio
Language	English