Check Rf Output Power - Tait TM9100 Service Manual

If the power supplies are correct, check the RF output power of the
Task 5 —
Check RF Output
transmitter.
Power
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Table 11.4 Tasks to be performed according to the results of the power and current measurements
of Task 5
Power
Correct
Correct
Skewed
Low (> 0.1W)
None at RF connector (< 0.1W)
None at RF connector (< 0.1W)
260 Transmitter Fault Finding (50W/40W Radios)
Enter the CCTM command 326 5 to set the transmitter power level
to the maximum value.
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
Enter the CCTM command 33 to place the radio in transmit mode.
Note the RF output power measured by the test set, and note the
current reading on the DC power supply.
RF output power: > 60W (VHF), > 52W (UHF)
current: < 15A (VHF), < 12A (UHF)
Enter the CCTM command 32 to place the radio in receive mode.
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 11.2.
Repeat Step 3 to Step 5.
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 11.2.
Repeat Step 3 to Step 5.
Depending on the results of the above measurements, proceed to the
task indicated in Table 11.4. Note that the power and current are
considered to be skewed if they are low at one part of the frequency
band and high elsewhere.
Current Task
Correct Task 6
Wrong Task 31
Skewed Task 9
Low (> 0.5A) Task 11
Low (> 0.5A) Task 31
None (< 0.5A) Task 7
Table 11.2.
— Power unchanged regardless of setting
— Check power at directional coupler
— Power and current are skewed
— Power and current are low
— Check power at directional coupler
— Check for inhibiting of transmitter
TM9100 Service Manual
© Tait Electronics Limited August 2005