Tait TM8100 mobiles Service Manual page 408

Task 7 —
Check
ITF RX BEEP IN
Input Signal
408 CODEC and Audio Fault Finding
If the output of the voice-band CODEC is not correct, check the
signal.
ITF RX BEEP IN
1. If not already done, remove the
2. Check the signal at the junction of R218 and IC204
(see Figure 13.4). The signal should be:
junction of R218 and IC204: sine wave about 1V
3. If the signal is correct, go to
(IC204) or the digital board is faulty; replace the board and go to
"Final Tasks" on page
4. Check for continuity between the
R214, R215 (see
Repair any fault; if necessary, replace R214, R215 or R218.
5. Confirm the removal of the fault and go to
page 163. If the repair failed or the fault could not be found, replace
the board and go to
CDC BOT
Step 4. If it is not, either CODEC 1
163.
200 test point and IC204 via
TP
Figure 13.2) and R218 (see
"Final Tasks" on page
© Tait Electronics Limited November 2007
can.
with 1.2V DC offset
pp
Figure 13.4).
"Final Tasks" on
163.
TM8100/TM8200 Service Manual