Output Of Buffer In Exciter Circuit; Output Of Exciter - Tait TM9100 Service Manual

If the synthesizer output is correct, check the output at C313 of the buffer
Task 26 —
Output of Buffer in
amplifier in the exciter circuit.
Exciter Circuit
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
If the output of the buffer amplifier is correct, check that of the exciter at
Task 27 —

Output of Exciter

C301.
1.
2.
3.
4.
5.
6.
358 Transmitter Fault Finding (25W Radios)
If not already done, remove the
Enter the CCTM command 326 x, where x defines the power level
selected in Task 25.
Enter the CCTM command 101 x x 0, where x is the frequency
selected in Task 25.
Enter the CCTM command 33 to place the radio in transmit mode.
Measure the RF voltage after C313 (see
RFP5401A RF probe or the equivalent.) The required voltage
should be as given in Table 12.8
Enter the CCTM command 32 to place the radio in receive mode.
If the voltage measured above is correct, go to
to Step 8.
Check the components around Q300 (see
Repair any fault revealed by the above checks. Replace Q300
(see Figure 12.15) if none of the other components is faulty.
Confirm the removal of the fault and go to
page 147. If the repair failed, replace the main-board assembly and go
to "Final Tasks" on page
With the radio still in transmit mode, measure the RF voltage after
C301 (see Figure 12.15). (Use an RFP5401A RF probe or the
equivalent.) The required voltage should be as given in
(B1 band) or Table 12.9
If the voltage is correct, go to
Enter the CCTM command 32 to place the radio in receive mode.
Check the components between C313 and Q303, and between
Q303 and R308 (see Figure
Repair any fault revealed by the above checks. Replace Q303
(see Figure 12.15) if none of the other components is faulty.
Confirm the removal of the fault and go to
page 147. If the repair failed, replace the main-board assembly and go
to "Final Tasks" on page
can.
PAD TOP
Figure 12.15). (Use an
(B1 band) or Table 12.9
Task
Figure
"Final Tasks" on
147.
(H5, H6).
Task 28. If it is not, go to
12.15).
"Final Tasks" on
147.
© Tait Electronics Limited August 2005
(H5, H6).
27. If it is not, go
12.15).
Table 12.8
Step 3.
TM9100 Service Manual