TM8100/TM8200 Service Manual
Transmitter Fault Finding (25W)
355
© Tait Electronics Limited
June 2006
Task 21 —
Check Power
Control
Check the power-control circuitry if the clamp current for the PA driver is
correct or if the voltage at the
SET
PWR
test point is incorrect.
Important
Ensure that the current limit on the DC supply is 2A.
And, when entering the CCTM command
304
z
, do not
specify a value
z
higher than that recorded in
ure to do so might result in the destruction of the PA driver.
1.
Enter the CCTM command
304
z
(where
z
was recorded in
).
2.
Note the current reading on the DC power supply.
3.
Enter the CCTM command
114 0
to switch off the power.
4.
Note the current reading on the DC power supply.
5.
Compare the above current readings. The current should decrease by
an amount approximately equal to the offset given in
. If it does
not, go to
.
6.
Check that the voltage from the DAC is changing. Measure the
voltage at the
PWR
test point
(
CDC
TX
PWR
CTL
) (see
7.
Enter the CCTM command
114 1023
. The voltage should increase
to:
8.
Enter the CCTM command
32
to place the radio in receive mode.
9.
If the voltage at the
PWR
test point
increases as required, go to
. If it does not, go to
“CODEC and Audio Fault Finding” on
PWR test point: 2.4
±
0.1V
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...