Final Tasks - Tait TB8100 Service Manual

8.14

Final Tasks

Task 1 —
Final Tests
Task 2 —
Final
Administration
170 Power Amplifier Fault Finding
Once you have completed the testing and repair (if required) of the PA,
carry out the following tasks.
Test the PA to confirm that it is fully functional again. The recommended
tests are listed below:
1. Check that the RF output power is correct when the PA is set to its
rated power.
2. Verify that the Service Kit shows the same RF output power (±10%)
as the power meter.
3. Check that the temperature readings displayed in the Service Kit are
within normal operating limits and no alarms have been generated.
For example:
If the PA is at ambient room temperature and not transmitting, the
readings in the Service Kit should match the ambient temperature.
If the PA has been transmitting recently, the readings should not
exceed the set thresholds.
4. Check that the DC supply current is within the specified limits when
transmitting and not transmitting (refer to
5. Inspect the PA to make sure that nothing has been damaged during
any test or repair procedures. Make sure all screws securing the cover
to the heatsink are in place and tightened to the correct torque.
It is good practice to record the test results on a separate test sheet. You can
then supply a copy of the test sheet to the customer as confirmation of the
repair.
The final administration tasks are the standard workshop procedures for
updating the fault database and returning the repaired PA to the customer
with confirmation of the repair.
If the PA could not be repaired for one of the following reasons:
fault not located
repair of fault failed
Level-1 service centres should return the faulty PA to the nearest Accredited
Service Centre, and level-2 service centres should return the PA to the
International Service Centre. Supply details of the customer, the fault and,
if applicable, the attempted repair.
Table 8.6 on page
TB8100 Service Manual
© Tait Electronics Limited September 2006
171).