Toshiba FT-8509 Service Manual page 22

6. TROUBLE WITH SPEAKERPHONE MODE
6-1. The voice of the caller cannot be heard (INCOMING CALL).
Check whether there is an
audio waveform on Pin 7 of
IC1.
OK
Check whether there is an
audio waveform on Pin 1 of
IC6.
OK
Check whether there is an
audio waveform on Pin 15 of
IC7.
OK
Check WF701 and SP701.
6-2. Voice cannot be transmitted to the calling party (OUTGOING CALL).
Check whether there is an
audio waveform on Pin 4 of
IC7.
OK
Check whether there is an
audio waveform on Pin 1 of
IC1.
OK
Check whether there is an
audio waveform on collector
of Q3.
OK
Check Q4, T1, RL1 and Q6.
NG
Check IC1.
NG
Check IC6, RL1 and Q6.
NG
Check IC7.
NG
Check MC251 and IC7.
NG
Check IC1.
NG
Check Q3.
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