Troubleshooting Flow Chart for 45W Transmitter (Sheet 1 of 2)
3-7
3.1
Troubleshooting Flow Chart for Transmitter (Sheet 2 of 2)
Pin 2
Voltage 0.62
* Voltage at
Pin 1?
NO
YES
Check PA Stages
No or too low Power when keyed
NO
YES
Replace U3401
Pin 3
Voltage 0.51
* Voltage at
Pin 1?
2-4V
Supply
0V
Bias 1 DC
Voltage at
TP3406?
NO
YES PCIC U3501
Pin 24 2-4V
DC?
Check Bias Tuning
before replacing
PCIC U3501
Check Voltage at Pin 2 & 3 of U3401
Replace U3401
Replace Q3421
NO
0V
1-4V
Bias 2 DC
Voltage at
TP3407?
YES
RF Voltage
at TP3401
>100mV?
YES
RF Voltage
U3401 Pin 6
>3V?
Replace
Q3421
Supply
Replace Q3431
Check FGU (U3301)
NO
Check Components
between TP3401 &
C3417
NO
YES
ASFIC
U0221 Pin 6
1-4V DC?
Check Bias Tuning
before replacing
ASFIC U0221
Check Components
between ASFIC and
Q3431 before
replacing Q3431
YES
RF Voltage
Q3421 Gate
>1V?
NO
Check Components
between C3417 &
Q3421
YES
RF Voltage
Q3431 Gate
>4V?
NO
Check Components
between Q3421 &
Q3431
YES
RF Voltage
Q3441 Base
>5V?
Check Components
between Q3431 &
Q3441
NO
Check Components
between Q3441 &
Antenna Connector
Voltage
Voltage
Summary of Contents for 6864115B62-C
Page 1: ...Professional Radio GM Series Detailed Service Manual 6864115B62 C ...
Page 2: ...ii ...
Page 4: ...iv ...
Page 5: ...Professional Radio GM Series Service Maintainability Issue July 2007 ...
Page 8: ...ii ...
Page 22: ...2 10 MAINTENANCE ...
Page 25: ...Professional Radio GM Series Controlhead Service Information Issue July 2007 ...
Page 77: ...Professional Radio GM Series Controller Service Information Issue May 2007 ...
Page 100: ...2 2 TROUBLESHOOTING CHARTS ...
Page 104: ...3 4 Controller schematics parts list ...
Page 154: ...3 52 Controller T12 Schematic Diagrams ...
Page 155: ...Professional Radio GM Series VHF 136 174MHz Service Information Issue May 2007 ...
Page 164: ...1 6 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 176: ...2 12 THEORY OF OPERATION ...
Page 186: ...3 10 TROUBLESHOOTING CHARTS ...
Page 190: ...4 4 VHF PCB SCHEMATICS PARTS LISTS ...
Page 252: ...4 66 VHF 1 25W PCB 8471235L02 Schematics VHF 136 174 MHz IF ...
Page 256: ...4 70 VHF 1 25W PCB 8471235L02 Schematics ...
Page 257: ...Professional Radio GM Series UHF 403 470MHz Service Information Issue May 2007 ...
Page 266: ...1 6 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 366: ...2 12 THEORY OF OPERATION ...
Page 372: ...3 6 Low Band TROUBLESHOOTING CHARTS ...