5.5
Signal processing section
Is the sound output from
both channels (L, R)?
YES
Normal
1-26 (No.MA028)
NO
No sound from either
channel.
YES
Is 9V present at IC301 pin
31?
YES
Is the audio signal
(including sampling output
components) output to
IC151 pins 1 and 7 during
playback?
YES
Is the audio signal output
at IC301 pins 3 and 30
during playback?
YES
Check the muting circuit.
NO
Compare the L-ch and
R-ch to locate the
defctive point.
NO
Check the viciniyt of the
Q321 audio power
supply.
NO
Check IC151 and its
peripheral circuits.
NO
Check IC301 and its
peripheral circuits.