Tait TP9100, Service Manual, Page: 288 / 326

288 CODEC and Audio Fault Finding
TP9100 Service Manual
© Tait Electronics Limited May 2005
Task 16 —
Check
AUD TAP IN
Audio and
Modulation
This task assumes that Task 15 has already been performed and passed,
which confirms the connection between
AUD TAP IN
and IC205.
1. Apply a 1kHz AC-coupled signal of 0.7 V
pp
at pin 8 (
AUD TAP IN
) of
the connector PL1 (see Figure 12.1 ).
2. Enter CCTM command
33
to place radio in transmit mode.
3. Enter CCTM command 323 t5 to select
AUD TAP IN
as modulation
source.
4. Check the modulation of the radio. If there is no modulation, go to
“Frequency Synthesizer Fault Finding” on page 159 . If there is
modulation, the hardware is not faulty. Check the setup of the audio
tap points in the programming application.
5. Enter CCTM command 32 to place the radio in receive mode.