Tait TM8000 Series Service Manual page 243

Task 5 —
Faulty Speaker Audio
at Auxiliary Connector
TM8100 Mobile Radio Service Manual
May 2004 © Tait Electronics Limited
If the receiver operates normally but there is no speaker audio at the
auxiliary connector, proceed as follows:
Enter the CCTM command 400 x, where x is a valid channel
1.
number. (A suitable channel will depend on the programming of
the radio.)
Enter the CCTM command 21 to force unmuting of the received
2.
audio signal.
Enter the CCTM command 110 128 to set the audio level at its
3.
midpoint.
4. At the test set apply 60%, 1 kHz modulation to the RF signal.
Reduce the volume to a minimum.
Enter the CCTM command 324 r5. Check that the received
5.
signal is present with an offset of 2.4 V DC at pin 13 (
of the auxiliary connector (alternatively, as
2B6/2G3] at the junction of R207 and R208 — see
If it is, go to Step 6. If it is not, return to
replace the complete main-board assembly.
6. Remove the
CDC BOT
2E6/2H4] of IC201 is 1.2 V, and that the voltage at pin 7 [at
2D6/2G3] is 2.4 V (see
Subsection 8.1
they are not, go to Step 7.
7. Check the circuits involving IC201 (pins 1 to 3 and 5 to 7).
Repair any fault. Confirm the removal of the fault and return to
Subsection 8.1. If the repair failed or the fault could not be found,
return to Subsection 8.1
assembly.
can. Check that the voltage at pin 1 [at
Figure 9.32). If they are, return to
and replace the complete main-board assembly. If
and replace the complete main-board
Diagnosis of Faults on Main Board
)
AUD TAP OUT
[at
CDC AUD TAP OUT
Figure 9.32).
Subsection 8.1 and
243