[Ed in Tx]

Originally Posted by jfrog1983

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There is 3 I would like to fix but don't know exactly whats wrong with them...

1. Hitachi made RCA with Hi-Fi but only 2 heads, has the brush type motor that drives the capstan and reels. It seems to be really confused, sometimes the buttons don't work at all and sometimes they are all mixed up i.e. you push play and it goes into rewind. I remember when I could get it to play it would have color interference on the screen that got worse and worse as it warmed up, and also the front clock display goes out at that point too, I believe its the power supply, but I don't know where to find another....

Probably filter caps failed in DC-DC converter circuit on display board causing interference and clock failing some had discrete parts in that circuit later models had a DC-DC converter module. Also as I recall some the Tape End and/or Take Up sensor phototransistor could fail and cause oddball operation like going into Rewind when you press Play etc.

2. Akai that looks more like a tape deck, the loading motor doesn't respond to any commands however the motor is good....

Some old ones had a sensor incandescent bulb that when failed nothing functions. Several variations of old Akai so not sure.

3. NEC made Yamaha that I think needs new caps in the power supply or new power supply itself. When cold, interference patterns all over the screen, noisy Hi-Fi and only one channel works, after its warmed up it works fine!...

Electrolytic capacitors in PS, tuner circuit, video circuit etc... fun! You need a good ESR meter to check caps with because replacing them all would be quite a chore.