JVC HR-V506EL Service Manual page 39

(2) No sound (Mono Model)
No sound
Check the Vcc of IC301 Pin 18.
Check the Tuner Audio signal
at IC301 Pin 13.
Check the Audio signal at IC301 Pin 11.
Check the signal flow from IC301
pin 11 to IC901 Pin 6.
YES
YES
YES
YES
NO
Check 5VT power.
NO
Chekc the signal flow from TU701
Pin21 to IC301 Pin 13.
NO
Replace IC301.
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