Audio - Tait TB8100 Service Manual

3.10

Audio

Task 1 —
Check Audio Output
Using Internal Test
Tone
TB8100 Service Manual
© Tait Electronics Limited September 2006
These checks will verify whether the input and output line levels are correct.
Figure 3.6 on page 90
Figure 3.7 on page 91
and Figure 3.8 on page 94
interface board.
1. Set up the test equipment as shown in
2. Run the Service Kit and connect to the reciter. Put the reciter in
Standby mode. Select Diagnose > Reciter > Audio I/O.
3. In the Output area, select Balanced line out or Unbalanced line
out.
Note
Terminate the balanced line output into 600Ω. Ensure there is
only a single load when running the test. Don't use the CTU's
internal load and an external termination.
4. Click Start Test.
5. View the Audio Output gauge and check that the measured output
level is the same as the level displayed on the gauge.
Note
The Level box displays the line sensitivity of the currently selected
channel. The audio output will be set to this level when the test
is started.
6. Click Stop Test. If the levels are correct, go to
incorrect, go to
7. Check the test set-up and repeat the test. If the levels are correct, go
to Task 2. If they are incorrect, recalibrate the line levels using the
Calibration Kit and repeat the test. If the line levels are now correct,
go to Task 2.
If the line levels are still incorrect, either the digital board or system
interface board is faulty. If the measured output voltage is greater than
the voltage displayed on the gauge, go to
put voltage is less than the voltage displayed on the gauge, go to
Step 9.
shows the recommended test equipment set-up.
shows the location of test points on the digital board,
shows the location of test points on the system
Step 7.
Figure 3.6.
Task 2. If they are
Step 8. If the measured out-
Reciter Fault Finding 89