212
Frequency Synthesizer Fault Finding
TM9100 Service Manual
© Tait Electronics Limited
August 2005
Task 31 —
Check Transmit-
Receive Switch
If no frequency is detected in the check of the VCO, first check that the
transmit-receive switch is functioning correctly.
1.
Resolder R542 in position (see
Figure 9.12
).
2.
Remove the
VCO
BOT
can.
3.
Enter the CCTM command
335 0
to switch on the supply to the
RX
port.
4.
Measure the voltage at pin 2 of D5004 (see
Figure 9.13
). (Some RF
noise might be observed.) The voltage should be:
5.
Enter the CCTM command
335 1
to switch off the supply.
6.
Again measure the voltage at pin 2 of D5004.
7.
If the voltages measured in
Step 4
and
Step 6
are correct, go to
Step 8
. If they are not, the switching network is suspect; go to
Task 32
.
8.
Enter the CCTM command
335 1
to switch on the supply to the
TX
port.
9.
Measure the voltage at pin 1 of D5004 (see
Figure 9.13
). (Some RF
noise might be observed.) The voltage should be:
10.
Enter the CCTM command
335 0
to switch off the supply.
11.
Again measure the voltage at pin 1 of D5004.
12.
If the voltages measured in
Step 9
and
Step 11
are correct, go to
Task 33
. If they are not, the switching network is suspect; go to
Task 32
.
pin 2 of D5004: 5.0
±
0.3 V DC (after entry of CCTM 335 0)
pin 2 of D5004: 0 V DC (after entry of CCTM 335 1)
pin 1 of D5004: 5.0
±
0.3 V DC (after entry of CCTM 335 1)
pin 1 of D5004: 2.1
±
0.4 V DC (after entry of CCTM 335 0)
Summary of Contents for TM9100
Page 1: ...TM9100 mobiles Service Manual MMA 00017 01 Issue 1 August 2005 ...
Page 4: ...4 TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 10: ...10 TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 22: ...22 Introduction TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 62: ...62 Description TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 96: ...96 TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 138: ...138 Disassembly and Reassembly TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 152: ...152 Servicing Procedures TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 168: ...168 Interface Fault Finding TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 244: ...244 Receiver Fault Finding TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 396: ...396 CODEC and Audio Fault Finding TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 420: ...420 Fault Finding of Control Head TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 426: ...426 Spare Parts TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 430: ...430 TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 444: ...444 TMAA04 05 Ignition Sense Kit TM9100 Service Manual Tait Electronics Limited August 2005 ...
Page 448: ...448 TMAA10 01 Desktop Microphone TM9100 Service Manual Tait Electronics Limited August 2005 ...