TM8100/TM8200 Service Manual
Frequency Synthesizer Fault Finding
233
© Tait Electronics Limited
November 2007
Task 33 —
Check Buffer
Amplifier
If no VCO frequency is detected but the switching network is not faulty,
check the buffer amplifier. If the amplifier is not faulty, there might be a fault
in the VCO that was not detected earlier.
1.
Enter the CCTM command
335 0
to set the transmit-receive switch
off.
2.
Measure the voltage at pin 3 of
D5004
(see
Figure 9.15
). (Some RF
noise might be observed.)
3.
Measure the voltage at pin 1 of
Q5001
(see
Figure 9.15
).
4.
If the voltages measured in
Step 2
and
Step 3
are not correct, go to
Step 5
. If they are, check the VCO circuitry based on
Q5000
(see
Figure 9.15
). Conclude with
Step 6
.
5.
The buffer amplifier is suspect. Check the buffer circuitry (based on
Q5001
) (see
Figure 9.15
).
6.
If a fault is found, repair the circuit, and confirm that the voltages are
now correct. If they are, go to
“Final Tasks” on page 163
. If they are
not, or if no fault could be found, replace the board and go to
“Final
Tasks” on page 163
.
pin 3 of D5004: 4.2
±
0.2V DC
pin 1 of Q5001: 0.7
±
0.2V DC
Содержание TM8100 mobiles
Страница 1: ...TM8100 mobiles TM8200 mobiles Service Manual MMA 00005 05 Issue 5 November 2007...
Страница 10: ...10 TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 12: ...12 TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 20: ...20 Introduction TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 64: ...64 Description TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 106: ...106 TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 134: ...134 General Information TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 168: ...168 Servicing Procedures TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 184: ...184 Interface Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 246: ...246 Frequency Synthesizer Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 340: ...340 Transmitter Fault Finding 25W TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 398: ...398 Transmitter Fault Finding 25W TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 422: ...422 CODEC and Audio Fault Finding TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 464: ...464 Spare Parts TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 488: ...488 TMAA01 01 Line Interface Board TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 541: ...TM8100 TM8200 Service Manual Installing a Remote Kit 541 Tait Electronics Limited November 2007 Circuit Diagram...
Страница 544: ...544 Installing a Remote Kit TM8100 TM8200 Service Manual Tait Electronics Limited November 2007 Circuit Diagram...
Страница 578: ...578 TMAA04 04 Crossband Linking Cable TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 592: ...592 TMAA10 01 Desktop Microphone TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...
Страница 612: ...612 TMAA10 08 Desktop Microphone TM8100 TM8200 Service Manual Tait Electronics Limited November 2007...