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Troubleshooting
●
No Sound
Check TV audio signal circuit.
TV SIF signal is output from IC201 and sent to IC3400(TV sound
processor IC). NICAM signal is decoded in IC3400. TV_L/R signals
are output from IC3400 and sent to IC3001(Selector IC) .
--> Check IC201, IC3400 and peripheral circuit.
Is TV audio signal
observed at pins 62 and
64 of IC3001?
Check audio amp.and control circuit.
--> Check 33V_AUD power supply line.
-->
Check IC041(audio-amp IC), IC001(audio control IC) and periph-
eral circuit.
MUTE signal (Mute:L) is applied on pin 11 of IC041 from pin 10 of
IC001. If a headphone is connected at the phone terminal, MUTE sig-
nal is also applied on IC041.
--> Check MUTE signal.
Is the audio signal
observed at pins 12 and
7 of IC041?
Check audio output circuit.
-->
Check speaker, connection of the terminal “K01R/K01L”.
Yes
No
Yes
No
Check following steps.
Check audio selecting circuit.
All of the audio input signals are selected in IC3001.
-->
Check IC3001 and peripheral circuit.
Is the audio signal
observed at pins 1 and
32 of IC001?
Yes
No
No sound with TV input
source
No sound with all of
input sources
Yes
Yes
Check headphone audio amp. circuit.
--> Check 5V_PH power supply line.
Audio signals from IC001 are amplified in IC051(phone amp. IC).
-->
Check IC051 and peripheral circuit.
MUTE signal (Mute:L) is applied on pin 2 of IC051 from pin 10 of
IC001. --> Check MUTE signal.
Yes
Check woofer audio amp. circuit.
--> Check 9VA power supply line.
Audio signal from IC001 is amplified in IC031(woofer amp. IC).
-->
Check IC031 and peripheral circuit.
No signal mute signal (Mute:H) is applied to IC2091 from pin 12 of
IC6301.
--> Check MUTE signal.
No sound with woofer
Yes
No sound with head-
phone
No
No
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