KD-S747
(No.49822)1-25
3.2.5 Signal processing section
No sound from either
channel.
Is 9V present at IC101 pin
(8)?
Compare the L-ch and
R-ch to locate the
defective point.
Is the sound output from
both channels (L, R)?
Check the vicinity of the
Q981 audio power
supply.
NO
NO
NO
NO
YES
YES
YES
YES
YES
Check IC521 and its
peripheral circuits.
Is the audio signal
(including sampling output
components) output to
IC521 pins ^and | during
Is the audio signal output
at IC101 pins 1
and7during playback?
NO
Check IC101 and its
peripheral circuits
Check the muting circuit.
Normal