TM8100/TM8200 Service Manual
Interface Fault Finding
177
© Tait Electronics Limited
June 2006
Task 2 —
Check Input Lines
For an input line suspected or reported to be faulty, proceed as follows:
1.
For a suspect
CH ON OFF
. For all other input lines go
to
2.
For the suspect line, apply a 3.3V DC test signal to a connector mated
to the radio connector in question.
3.
Check the internal signal for the line under test. If 3.3V DC is
present, go to
. If it is not, go to
.
4.
For the
CH
ON
OFF
line, apply a short to ground on pin 5 of a connector
mated to the control-head connector. Check that there is 3.9V DC
present on the
ITF ON OFF
line, and that
PSU
ON
OFF
is approximately
equal to the radio’s primary supply voltage, nominally 13.8V DC.
5.
Remove the short on the connector. Check that, with
CH ON OFF
open-circuit, both
ITF
ON
OFF
and
ITF
PSU
ON
OFF
are close to 0.0V.
6.
are observed, go to
7.
The fault lies with the radio’s internal circuitry. If the power-supply
circuitry or the CODEC and audio circuitry is suspect, continue with
the fault diagnosis as in
“Power Supply Fault Finding” on page 163
and
“CODEC and Audio Fault Finding” on page 381
, respectively.
If the digital board is suspect, replace the board and go to
.
8.
The fault lies in the filtering, basic processing, or connector for the
line under test. Re-solder components or replace faulty components
as necessary. Confirm the removal of the fault and go to
. If the fault could not be found, replace the board and
go to
.
Task 3 —
Bi-directional Lines
For a bi-directional line suspected or reported to be faulty, proceed as
described below. In the procedure the direction of the line will need to be
configured. For information on this topic consult the on-line help facility
on the programming application’s
“Programmable I/O”
page.
1.
Configure the suspect line as an output, and then carry out the
procedure given in
2.
Configure the suspect line as an input, and then carry out the
procedure given in
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...
