TP9100 Service Manual Frequency Synthesizer Fault Finding 207
© Tait Electronics Limited May 2005
Task 34 —
Power Supply
If the FCL is suspect, first check that the 3V power supply is not the cause
of the fault.
1. If not already done, remove the
FCL TOP can and place the radio in
CCTM.
2. Measure the supply +3
V0 AN at the via shown in Figure 9.19.
3. If the voltage is correct, go to “VCXO and VCTCXO Outputs” on
page 208. If it is not, the 3V regulator IC604 is suspect; go to Tas k 4
of “Power Supply Fault Finding” on page 156.
via adjacent R536: 3.0 ± 0.06V DC
Figure 9.19 FCL circuitry under the FCL TOP can (top side)
3V0 AN
VCTCXO
output
VCXO output
Position of
R527 for test
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