Check Lpf Components - Tait TM9100 Service Manual

If there are no faults in the final RF signal path up to and including the PIN
Task 33 —
Check Components
switch, then the fault should lie in the LPF. Check the LPF as follows:
of LPF
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
TM9100 Service Manual
© Tait Electronics Limited August 2005
Remove the can.
LPF TOP
Connect the RF connector to the test set.
Check the capacitors and inductors of the LPF between the PIN
switch and the RF connector. See
open circuits, and faulty components. Repair any fault.
Enter the CCTM command 326 5 to set the transmitter power level
to the maximum.
Enter the CCTM command 101 x x 0, where x is the lowest
frequency (in hertz) for maximum power, as given in
(B1 band) or Table 12.9
Enter the CCTM command 33 to place the radio in transmit mode.
Measure the RF output power. This should exceed 35W.
RF output power: more than 35W
Enter the CCTM command 32 to place the radio in receive mode.
Enter the CCTM command 101 x x 0, where x is the highest
frequency (in hertz) for maximum power, as given in
(B1 band) or Table 12.9
Repeat Steps Step 6 to Step
If the power in both the above cases exceeds 35 W, the fault has been
rectified; go to "Final Tasks" on page
failed; replace the main-board assembly and go to
page 147.
Transmitter Fault Finding (25W Radios)
Figure 12.20. Check for shorts,
(H5, H6).
(H5, H6).
8.
147. If it does not, the repair
"Final Tasks" on
Table 12.8
Table 12.8
369