Operating instructions

9-4 800/900 Band Troubleshooting Charts
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START
Check 2.8V at E001 & E002,
2.8V at E004, 1.875V at
E006, 5V at E003.
Are supplies
present?
Inspect supply from U3000.
16.8MHz signal from
Y001?
Inspect Y001, R001, R002,
C010, C011, C012 and C043
16.8MHz signal at
pin L5 of U001?
Is C028 at 1.0V -
9.5VDC?
Is C028 at >
11VDC?
Inspect D002, D003, R018,
C031, C032, C033, C034, C035
& C036.
Check if R007, R008, R009,
C021, C023, C024, C025,
C026, C027 & C028 are OK ?
Check 2.7VDC at pin C5 of U001 in RX
mode, check 2.5VDC at pin 3 of Q001 in
TX mode and 4.5VDC at pin J5 of U001.
Are supplies
present ?
Is RF level at pin G1
of U001 > -15dBm?
Check if L001,
R006, C013, C014
& C015 are OK ?
Check VCO
Replace part
Replace U001
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Troubleshooting Flow Chart for Synthesizer