360
Transmitter Fault Finding (25W)
TM8100/TM8200 Service Manual
© Tait Electronics Limited
June 2006
Task 24 —
Power Control
and Shaping Filter
In this task any faults in the power-control and shaping-filter circuitry will
be located:
1.
Measure the voltage at pin 8 of
IC303
(see
power-control circuit. The voltage should be:
2.
If the voltage is correct, go to
. If it is not, enter the CCTM
command
32
3.
Measure the voltage at pin 10 of
IC303
(see
) in the
power-control circuit. The voltage should be:
4.
If the voltage is correct, go to
.
5.
Enter the CCTM command
32
to place the radio in receive mode.
6.
Check
C322
,
C324
,
R342
,
R347
(see
) in the power-
control circuit.
7.
Repair any fault revealed by the checks in
. Replace
IC303
(see
) if none of the other components is faulty. Confirm
the removal of the fault and go to
. If the
repair failed, replace the board and go to
8.
Measure the voltage at pin 1 of
IC301
(see
shaping-filter circuit. The voltage should be:
9.
Enter the CCTM command
32
to place the radio in receive mode.
10.
If the voltage measured in
. If it is not,
11.
Check the components
R334
(see
C319
(see
) and go to
.
12.
Check the components between the
PWR
test point
and pin 1 of
IC301
(see
) and go to
.
13.
Repair any fault revealed by the checks in
.
Replace
IC301
(see
) if none of the other components
is faulty. Confirm the removal of the fault and go to
. If the repair failed, replace the board and go to
.
pin 8 of IC303: 7.4
±
0.5V
pin 10 of IC303: 4.8
±
0.5V
pin 1 of IC301: 4.8
±
0.5V
Summary of Contents for TM8235
Page 1: ...TM8100 mobiles TM8200 mobiles Service Manual MMA 00005 04 Issue 4 June 2006...
Page 10: ...10 TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 62: ...62 Description TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 148: ...148 Disassembly and Reassembly TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 162: ...162 Servicing Procedures TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 178: ...178 Interface Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 258: ...258 Receiver Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...
Page 446: ...446 Spare Parts TM8100 TM8200 Service Manual Tait Electronics Limited June 2006...