Tait TM9100 Service Manual page 328

If all the power and current values measured in
Task 6 —
Power Unchanged
that the power remains unchanged regardless of the power setting.
Regardless of
Setting
1.
2.
If the transmitter is drawing no current or the wrong current, check
Task 7 —
Check for Inhibiting
whether it is being inhibited. This check is also required if a CO3 error
of Transmitter
occurs in
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
328 Transmitter Fault Finding (25W Radios)
Enter the following CCTM commands in turn and measure the RF
output power in each case:
326 4
326 3
326 2
326 1
The above measurements should confirm that the power remains
unchanged at all settings. Carry out
Task 1.
If not already done, enter the CCTM command 33 to place the radio
in transmit mode.
Check the logic signal at the
The signal should be:
TX INH test point: about 0V (inactive)
If the signal is inactive as required, go to
1.1V — the transmitter is being inhibited; go to
Enter the CCTM command 32 to place the radio in receive mode,
and go to Task 12 in "Biasing of PA Driver and PAs" on page
Check the logic signal at the
The signal should be:
D TX INH test point: about 0V (inactive)
If the signal is inactive as required, go to
3.2V — the temperature sensor is suspect; go to
Enter the CCTM command 32 to place the radio in receive mode,
and go to Task 8.
The lock status is possibly no longer normal. Enter the CCTM
command 72 and check the lock status.
Enter the CCTM command 32 to place the radio in receive mode.
The normal lock status is 110. If it is not, proceed to the relevant
section. If it is, go to Step
Check for short circuits on the
point.
Task 5 are correct, it is likely
Task 12 and then
test point (see
TX INH
Step 4. If it is active — about
Step
test point (see
D TX INH
Step 8. If it is active — about
Step
11.
line from the
DIG TX INH
TM9100 Service Manual
© Tait Electronics Limited August 2005
Task 19.
Figure 12.4).
5.
335.
Figure 12.4).
7.
test
D TX INH