Tait TP9100, Service Manual, Page: 224 / 326

224 Transmitter Fault Finding
TP9100 Service Manual
© Tait Electronics Limited May 2005
10.2 Transmitter RF Power
Introduction
If there is no fault with the power supplies, check the transmitter RF power
and correct any fault. The procedure is covered in the following eight tasks:
■
Task 3: check RF output power
■
Task 4: power unchanged regardless of setting
■
Task 5: check for inhibiting of transmitter
■
Task 6: check temperature sensor
■
Task 7: power and current are skewed
■
Task 8: power and current are low
The measurement points for diagnosing faults concerning the transmitter
RF power are summarised in
Figure 10.4 .
Task 3 —
Check RF Output
Power
If the power supplies are correct, check the RF output power of the
transmitter.
1. Enter the CCTM command
326 4
to set the transmitter power level
to high power.
2. If not already done, program the radio with the highest frequency in
the radio’s frequency band: Enter the CCTM command
101 x x 0 ,
where
x
is the frequency in hertz. The required values for the
different frequency bands are given in Table 10.2 on page 218 .
3. Enter the CCTM command
33
to place the radio in transmit mode.
4. Note the RF output power measured by the test set, and note the
current reading on the DC power supply.
5. Enter the CCTM command 32 to place the radio in receive mode.
6. Program the radio with the center frequency in the radio’s frequency
band: Enter the CCTM command
101 x x 0 , where x is the frequency
in hertz. The required values for the different frequency bands are
given in
Table 10.2 on page 218 .
7. Repeat Step 3 to Step 5 .
8. Program the radio with the lowest frequency in the radio’s frequency
band: Enter the CCTM command
101 x x 0
, where
x
is the frequency
in hertz. The required values for the different frequency bands are
given in
Table 10.2 on page 218 .
RF output power: >5W (for B1 band); >4W (H5 and H6 bands)
current: <1.9A