TM8100 Mobile Radio
Service Manual
Diagnosis of Faults on Main Board
183
May 2004 © Tait Electronics Limited
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
respectively. If the digital board is suspect, return
to
and replace the complete main-board assembly.
8.
The fault lies in the filtering, basic processing, or connector for the
line under test. Re-solder components or replace faulty com-
ponents as necessary. Confirm the removal of the fault and return
to
. If the fault could not be found, return to
and replace the complete main-board assembly.
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 Task 1.
2.
Configure the suspect line as an input, and then carry out the
procedure given in Task 2.
9.3
Frequency Synthesizer
Introduction
This subsection covers the diagnosis of faults in the frequency
synthesizer. The synthesizer is a closed-loop control system. A fault in
one area can cause symptoms to appear elsewhere. Locating the fault can
therefore be difficult. The fault-diagnosis procedure is divided into four
tasks. First discussed, however, is the lock status of the radio, which will
indicate whether or not the synthesizer is suspect.
Lock Status
The lock status of the radio might already have been determined as part
of the preliminary fault diagnosis. The following is a summary:
1.
Enter the CCTM command
33
to place the radio in transmit
mode. Enter the command
72
to determine the lock status in this
mode. Note the response. The normal status is
110
.
2.
Enter the CCTM command
32
to place the radio in receive mode.
Enter the command
72
to determine the lock status in this mode.
Note the response. The normal status is
111
.
3.
If the lock status in either or both receive and transmit mode is
a
0
a
, where
a
is
0
or
1
, the FCL is suspect; go to
.
4.
If the lock status is
011
or
010
in receive mode or
010
in transmit
mode, the synthesizer is suspect; proceed to Task 1. (If the status
is
010
in receive mode, investigate the receiver later also.)
Содержание TM8000 Series
Страница 32: ...32 Introduction TM8100 Mobile Radio Service Manual May 2004 Tait Electronics Limited ...
Страница 78: ...78 Circuit Descriptions TM8100 Mobile Radio Service Manual May 2004 Tait Electronics Limited ...
Страница 106: ...106 General Information TM8100 Mobile Radio Service Manual May 2004 Tait Electronics Limited ...
Страница 124: ...124 Servicing Procedure TM8100 Mobile Radio Service Manual May 2004 Tait Electronics Limited ...
Страница 164: ...164 Servicing of Control Head TM8100 Mobile Radio Service Manual May 2004 Tait Electronics Limited ...
