Tascam 122 mk1 recording problem

[Shann]

Hello everyone!

I picked up a first generation 122 recently. Got the belts and pinch roller replaced and it plays my cassettes wonderfully now in both channels.

I say that because when recording, there's no sound in the left channel. With the monitor switch on source, I hear both channels. On tape, no left channel. Rewinding the tape and playing back normally also shows nothing being recorded in the left channel.

I unplugged the connector for the record head, depinned it and swapped the wires for the right and left channel and the problem moved to the right channel so I know my record head is good.

The problem persists with all bias, eq, noise reduction settings and with both inputs.

Has anyone ever encountered a problem like this? I'd appreciate any help that could send me in the right direction to fix this.

 

[Doorz]

As nobody has replied (and for future reference) here a belated answer , as I had the same issue on a TEAC C-3X which is in essence the same model.
Big probability that it's C323, a 1500pf polypropylene orange capacitor which belongs to those with the "orange cap disease" It's on the switch board with the Dolby encoder / HX circuit. Change the C423 also at the same time. I also changed the same value C146 and C246 which are next to the Op-amp on the record/playback main board. They are now replaced with red ones.


I had quite a lot of bad caps on the power supply board too, One 1000uf 25V had corroded leads because of the glue used to fix it on the board. C524 messed up the muting circuit, It stayed on and muted the playback even after engaging play, It should only stay on for a short instant to prevent hearing the capstan getting up to speed.