Tait TM8100 mobiles Service Manual page 191

Figure 9.2 Synthesizer circuitry under the SYN TOP can and the 6V regulator IC606 (top side) (cont.)
K5 band
Q512
Q508
Task 3 —
14V Power Supply
(B1 50W and K5:
15.5V)
TM8100/TM8200 Service Manual
© Tait Electronics Limited November 2007
Q506
First check the output
with a 9V DC supply from a 9V regulator in the PSU module.
1. Remove the board from the chassis.
2. Place the radio in CCTM.
3. Measure the SMPS output
R530 (see Figure
C531: 14.2V ± 0.3 DC
B1 50W from board revision -04 and K5: 15.5V ± 0.3 DC
Note
On A4 band radios, C531 and R530 are on the bottom side of the
PCB. Measure the
4. If the SMPS output is correct, go to
5. Check the 9V supply at Q500 and R533 (see
Q500 and R533: 9.0V ± 0.3 DC
6. If the voltage is correct, go to
IC601 is suspect; go to
page 174.
7. Remove the
FCL TOP
Q502 and L502 (see
Q507
TP503
from the SMPS, which is itself provided
VCL SUPPLY
VCL SUPPLY
9.2).
voltage on the via beside C5050.
VCL SUPPLY
Task
Step 7. If it is not, the 9V regulator
Task 3 of "Power Supply Fault Finding" on
can and check the SMPS circuit based on Q500,
Figure 9.3).
Frequency Synthesizer Fault Finding
Junction of
C541 and R547
at the via between C531 and
4. If it is not, go to
Figure 9.3).
Step 5.
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