$5 Riviera Deluxe

[electra225]

For the benefit of those of us who know zipkus about solid state circuits, Chris, would you share your thoughts on the suggestions you just posted? My guess is those caps are used for coupling caps. Am I even close?

[TC Chris]

I know minus zipkus, but I looked at the schematic and saw two caps, one probably paper/wax and the other electrolytic, series with the misbehaving balance control. Caps are a principal mode of failure, and the resistors in the circuit don't look to be heavily loaded, so I'm just guessing.

Chris Campbell

[stbasil]

Yeah, all electolytics replaced, the .1mf in the feedback circuits were not replaced, I didn't have but one handy, but the originals both checked good. While one channel was oscillating, the one with the single larger speaker, I tried substituting my one new .1mf, but no change in the oscillation, so I left the original. The oscillation follows that large speaker.

I've read that sometimes a particular speaker can destabilize a transistor amp due to its internal crossover circuit. If this little amp was designed for a particular set of speakers, I suppose that could be what's happening here.

I'm gonna shelve it for a while, since I just picked up a GE Wellington coffee table (see finds section). I'll start a new thread in the Other Consoles section for the GE.