
280
CODEC and Audio Fault Finding
TP9100 Service Manual
© Tait Electronics Limited
May 2005
Task 8 —
Check LPF and
Buffer Amplifier
If there is no test signal at the connector PL1, then either CODEC 1 is
faulty or there is a fault in the LPF or buffer amplifier.
1.
Remove the
CDC
BOT
can.
2.
At the test set apply 60%, 1 kHz modulation to the RF signal.
Reduce the volume to a minimum.
3.
Check the signal at
R224
(see
). This should be:
4.
If the above signal is correct, go to
. If it is not, CODEC 1
(
IC204
) is faulty; replace the main board and go to
5.
Check the voltage at pin 1 of
IC201
(see
6.
If the voltage is correct, go to
. If it is not, check the LPF
circuit based on
IC201
(pins 1 to 3) (see
). Repair any
fault and conclude with
7.
Check the voltage at pin 7 of
IC201
(see
).
8.
If the voltage is correct, go to
. If it is not, check the buffer
amplifier based on
IC201
(pins 5 to 7) (see
). Repair any
fault and conclude with
9.
Check
R207
and
R208
(see
). Repair any fault and
conclude with
10.
Confirm the removal of the fault and go to
. If the repair failed
or the fault could not be found, replace the main board and go to
11.
If there is also a fault with the transmit modulation, notwithstanding
modulation at the accessory connector, go to
Using Accessory Audio Tap In” on page 287
. If there is no other
fault, go to
R224: 0.7 V
pp
with 1.2V DC offset
pin 1 of IC201: 0.7V
pp
with 1.2V DC offset
pin 7 of IC201: 0.7V
pp
with 1.2V DC offset
Содержание TP9100
Страница 1: ...TP9100 portables Service Manual MPA 00005 01 Issue 1 00 May 2005 ...
Страница 4: ...4 TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 10: ...10 TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 11: ...TP9100 Service Manual 11 Tait Electronics Limited May 2005 TP9100 portables Chapter 1 Description of the Radio ...
Страница 74: ...74 Circuit Descriptions TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 75: ...TP9100 Service Manual 75 Tait Electronics Limited May 2005 TP9100 portables Chapter 2 Servicing the Radio ...
Страница 78: ...78 TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 100: ...100 General Information TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 126: ...126 Disassembly and Reassembly TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 148: ...148 Interface Fault Finding TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 158: ...158 Power Supply Fault Finding TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 250: ...250 Transmitter Fault Finding TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 268: ...268 Receiver Fault Finding TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 292: ...292 Spare Parts TP9100 Service Manual Tait Electronics Limited May 2005 Figure 13 1 Serviceable parts 3 3 3 4 4 3 4 ...
Страница 294: ...294 Spare Parts TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 295: ...TP9100 Service Manual 295 Tait Electronics Limited May 2005 TP9100 portables Chapter 3 Accessories ...
Страница 298: ...298 Antenna Identification Chart TP9100 Service Manual Tait Electronics Limited May 2005 ...
Страница 306: ...306 TPA CH 001 Single Battery Charger TP9100 Service Manual Tait Electronics Limited May 2005 15 6 5 Circuit Diagram ...