Motorola GM328 Service Manual page 257

Troubleshooting Flow Chart for 25W Transmitter
Troubleshooting Flow Chart for 25W Transmitter (Sheet 3 of 3
2.2
Check Components
between ASFIC and
Q5441 before
replacing Q5441
ASFIC
YES
U0221 Pin 6
1-4V DC?
NO
Check Bias Tuning
before replacing ASFIC
U0221
Check Final PA Stage
Supply
Voltage
Bias 2 DC
0V
Voltage at
TP5406?
1-4V
NO
RF Voltage
at TP5401
>100mV?
YES
NO
RF Voltage
U5401 Pin 6
>3V?
YES
NO
RF Voltage
Q5421 Gate
>1V?
YES
RF Voltage NO
Q5441 Gate
>4V?
YES
Check Components
between Q5441 &
Antenna Connector
)
Replace Q5441
Check FGU (U5301)
Check Components
between
TP5401 &C5417
Check Components
between
C5417 & Q5421
Check Components
between
Q5421 & Q5441
3-5