TM8100/TM8200 Service Manual
Transmitter Fault Finding (>25W)
331
© Tait Electronics Limited
November 2007
Task 32 —
Repair Circuitry
If the RF output power measured in
Task 31
is low, there is a fault in the
circuit between the common drain of the PAs and the test capacitor.
1.
If not already done, remove the
PAF
TOP
can.
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
Step 5
. If no
fault could be found, go to
Step 4
.
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
Figure 11.26
), and go to
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.
6.
Enter the CCTM command
101
x x
0
, where
x
is the lowest
frequency (in hertz) for maximum power, as given in
Table 11.8
(B1),
Table 11.9
(G2),
Table 11.10
(H5),
Table 11.11
(H7), or
Table 11.12
(K5).
7.
Enter the CCTM command
33
to place the radio in transmit mode.
8.
Measure the RF output power. This should be:
9.
Enter the CCTM command
32
to place the radio in receive mode.
10.
Enter the CCTM command
101
x x
0
, where
x
is the highest
frequency (in hertz) for maximum power, as given in
Table 11.8
(B1),
Table 11.9
(G2),
Table 11.10
(H5),
Table 11.11
(H7), or
Table 11.12
(K5).
11.
Repeat
Step 7
to
Step 9
.
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
Figure 11.26
).
13.
If the power in both the above cases is now correct, the fault has been
rectified; go to
“Final Tasks” on page 163
. If it is not, the repair
failed; replace the board and go to
“Final Tasks” on page 163
.
RF output power: more than 70W (VHF)
more than 60W (UHF)
more than 52W (700MHz)
more than 58W (800MHz)
Summary of Contents for TM8100 mobiles
Page 1: ...TM8100 mobiles TM8200 mobiles Service Manual MMA 00005 05 Issue 5 November 2007...
Page 10: ...10 TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 12: ...12 TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 20: ...20 Introduction TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 64: ...64 Description TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 106: ...106 TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 134: ...134 General Information TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 168: ...168 Servicing Procedures TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Page 464: ...464 Spare Parts TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
