Tait TM8100 mobiles Service Manual page 331

Task 32 —
Repair Circuitry
TM8100/TM8200 Service Manual
© Tait Electronics Limited November 2007
If the RF output power measured in
circuit between the common drain of the PAs and the test capacitor.
1. If not already done, remove the
2. Check for faulty, shorted or misplaced components in the circuit
between the test capacitor and the common drain of Q309 and Q310
(see Figure 11.6).
3. Repair any fault revealed by the above checks and go to
fault could be found, go to
4. Remove the test lead and test capacitor, resolder the coupling
capacitors C348, C349 and C350 for the VHF and UHF bands or
C350 for the K5 band in position (see
Task 26.
5. With the test lead still connected to the test set, 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
6.
frequency (in hertz) for maximum power, as given in
(B1), Table 11.9
Table 11.12 (K5).
Enter the CCTM command 33 to place the radio in transmit mode.
7.
8. Measure the RF output power. This should be:
RF output power: more than 70W (VHF)
Enter the CCTM command 32 to place the radio in receive mode.
9.
Enter the CCTM command 101 x x 0, where x is the highest
10.
frequency (in hertz) for maximum power, as given in
(B1), Table 11.9
Table 11.12 (K5).
11. Repeat Step 7 to
12. Remove the test lead and test capacitor, and resolder the coupling
capacitors C348, C349 and C350 for the VHF and UHF bands or
C350 for the K5 band in position (see
13. If the power in both the above cases is now correct, the fault has been
rectified; go to
failed; replace the board and go to
Task 31
PAF TOP
Step 4.
(G2), Table 11.10
more than 60W (UHF)
more than 52W (700MHz)
more than 58W (800MHz)
(G2), Table 11.10
Step 9.
"Final Tasks" on page
"Final Tasks" on page
Transmitter Fault Finding (>25W)
is low, there is a fault in the
can.
Step
Figure 11.26), and go to
Table 11.8
(H5), Table 11.11 (H7), or
Table 11.8
(H5), Table 11.11 (H7), or
Figure 11.26).
163. If it is not, the repair
163.
5. If no
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