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JVC A-X1 amp. Lost left channel on Phono.

My old A-x1 has just lost the left channel on phono only. Aux and Tuner work fine. The channel became very noisy with distorting music, now nothing! Spray contact cleaned the switch. No difference. I can only assume there may be a problem in the equaliser amp TXX-240-2. I do not know much about electronics, but did re-cap my monitor successfully!! Anyone have ideas please?



Re: JVC A-X1 amp. Lost left channel on Phono.

Bad capacitors and/or transistors in the phono pre-amp stage would be my first guess.

Re: JVC A-X1 amp. Lost left channel on Phono.

Thanks Johnnysan, I was thinking that too. The capacitors don't look blown though. Transistors... which one?

Re: JVC A-X1 amp. Lost left channel on Phono.

This unit uses an IC for phono pre-amp. It could go bad and cause your problem.
IC 301 -- HA1452W

Other possibilities if changing the IC doesn't fix it
C301, and C313 for one channel -- 4.7uf at 50v each
C302, and C314 for the other channel -- 4.7uf at 50v each

But also check the solder connections from where the phono jacks connect to the circuit board and make sure connections are good, and that you don't have any circuit board cracks (They usually occur near one the screw mounting holes, holding the board to the chassis.)

Re: JVC A-X1 amp. Lost left channel on Phono.

Thanks very much for the information tbrander. I will see what works. Thanks again!