Tait TM8100 mobiles Service Manual page 236

Task 34 —
Power Supply
Figure 9.17 TCXO circuitry under the CDC TOP can
IF TOP CAN
236 Frequency Synthesizer Fault Finding
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 board from the chassis and place the
radio in CCTM.
Measure the supply +3
2.
is adjacent to the
via adjacent to CDC TOP can: 3.0 ± 0.3V DC
3. If the voltage is correct, go to
page 237. If it is not, the 3V regulator IC603 is suspect; go to
of "Power Supply Fault Finding" on page
0
at the via shown in
V AN
can.
CDC TOP
"VCXO and TCXO Outputs" on
VIA FOR MEASURING 3 V DC SUPPLY
© Tait Electronics Limited November 2007
Figure 9.17. The via
Task 3
174.
TM8100/TM8200 Service Manual