3-8
TROUBLESHOOTING CHARTS
4.0
Troubleshooting Flow Chart for VCO
Are Q200
Base at 2.9V
Collector at 6.6V
Emitter at 2.2V
Are U201 Pins
15 at 1.0V
10 at 3.9V
16 at 1.8V
Low or no RF Signal
at TP1
Visual check
of board
OK?
370mV DC at
U201 Pin 19
NO
YES
at base of Q200
NO
NO
NO
YES
YES
YES
Low or no RF Signal
at input to PA
4.5V DC at
U201 Pin 19
Is RF available
at C2060
YES
YES
YES
YES
NO
NO
NO
NO
NO
Audio =180mVRMS
at “-” S
ide of
4.5VDC
at D205
If R211 and R12 are OK,
then replace D205
Replace R211
Replace R212
NO
NO
YES
YES
If parts between
R109 & U201 Pin10
are OK, replace U201
TX VCO
RX VCO
Correct
Problem
Visual check
of board
OK?
Check runner
between U200 Pin 2
and U201 Pin 19
Is RF available
Replace U201
If all parts associated
with the pins are OK,
replace Q200
If all parts from collector
of Q200 to TP1 are
OK, replace Q200
Power OK but
no modulation
Check parts to pre-driver
If all parts
associated
with the pins
are OK,
replace U201
YES
YES
Make sure Synthesizer is
working correctly and runner
between U200 Pin 28 and
U201 Pin 14 & 18 is OK
4.5V DC
OK ?
OK?
OK?
D205
at U201 Pin 14 & 18
4.5V DC
OK ?
at U201 Pin 14 & 18
NO
Summary of Contents for cm200 Commercial Series
Page 1: ......
Page 2: ......
Page 3: ...M CM200 CM300 PM400 Radios Detailed Service Manual 6881098C00 A ...
Page 6: ...THIS PAGE INTENTIONALLY LEFT BLANK Notes ...
Page 7: ...CM200 CM300 PM400 Radios Service Maintainability Issue November 2007 M ...
Page 10: ...iv Notes ...
Page 12: ...vi Notes ...
Page 16: ...1 4 INTRODUCTION Notes ...
Page 24: ...2 8 MAINTENANCE Notes ...
Page 27: ...CM200 CM300 PM400 Radios Control Head Service Information Issue November 2007 M ...
Page 32: ...1 2 OVERVIEW Notes ...
Page 46: ...4 2 CONTROLHEAD PCB SCHEMATICS PARTS LISTS Notes ...
Page 53: ...CM200 CM300 PM400 Radios UHF2 438 470 MHz 1 25 W Service Information Issue November 2007 M ...
Page 58: ...vi Notes ...
Page 62: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS Notes ...
Page 96: ...4 2 UHF2 PCB SCHEMATICS PARTS LISTS Notes ...
Page 151: ...CM200 CM300 PM400 Radios UHF2 438 470 MHz 25 40 W Service Information Issue November 2007 M ...
Page 156: ...vi Notes ...
Page 160: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS Notes ...
Page 194: ...4 2 UHF2 PCB SCHEMATICS PARTS LISTS Notes ...
Page 222: ...4 30 UHF 25 40 W Band 2 PCB 8486577Z01 Schematics Notes ...
Page 250: ...4 58 UHF 25 40 W Band 2 PCB 8486577Z03 Schematics Notes ...
Page 251: ...CM200 CM300 PM400 Radios UHF3 465 495 MHz 25 40 W Service Information Issue November 2007 M ...
Page 256: ...vi Notes ...
Page 260: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS Notes ...
Page 294: ...4 2 UHF3 PCB SCHEMATICS PARTS LISTS Notes ...
Page 322: ...4 30 UHF 25 40 W Band 3 PCB 8486577Z01 Schematics Notes ...
Page 350: ...4 58 UHF 25 40 W Band 3 PCB 8486577Z03 Schematics Notes ...
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