Need Vox Cambridge 15 schematic and/or power amp IC info

[bluesky6]

After successfully repairing a Vox Cambridge 30 non-Twin, I managed to get a non-working Cambridge 15.

When I stripped the amp, I found many reasons why it wasn't working: power amp IC broken legs (don't ask me how), past repairs with solder joints that look like a liberal use of plumber's solder, torn traces (fool tech used desoldering pump instead of desoldering wick) with bad repairs etc etc.

I'm going to start with getting a new power amp IC.

Since the markings on the one that's in the amp is no longer visible, can someone advise me on the right amp?

It's probably one of the TDA20x0. The question is which one? I have several 30s and one 50s (left over from the Cambridge 30 repair), but it may be a 40 since we're talking 15W here...

A schematic would also be nice

[Jazz P Bass]

I do not believe that there is a schematic to be found for the Cambridge 15.

If it is a TDA20xx Pentawatt 5 legged ic, I would throw in a TDA2050.

[bluesky6]

Finally managed to work on the amp yesterday. The old power IC was a TDA2030A. So I swapped in another one.

I also reworked on some of bad solder work and re-did the audio-out wiring. The wires to the headphone/line-out/speaker-out daughterboard were falling apart.

The amp worked with the following problems:
1. Very low volume (gain at 12 o'clock and volume maxed out was softer than a Pathfinder 10)
2. Tremolo wasn't working

The opto-isolator had been replaced. So I'm wondering if that is part of the problem. The Cambridge 30s have a couple of trimmers to allow volume adjustment after an opto-isolator replacement but not the Cambridge 15.

A project for a rainy day except that it hardly ever rains in this part of California any more...

[J M Fahey]

*If* it were an amp which simply ceased working, repair would be more reasonable, and probably not much more than replacing the TDA or some "mechanical" problem (bad jack, pot or switch).
But if some muso worked there before ... who knows?
Big problem is that an experienced Tech who might "see through" the mistakes and repair it without schematic, will charge a lot.
And we Forum members who might help, donŽt even have a schematic.

Download the TDA datasheet and use it as a guide, worst case rebuild what you have exactly like the datasheet example and have it work .
After that , youŽll be able to try to repair the preamp stage by stage, using the power amp as a "built in signal tracer".

Looks like an indirect path but lacking everything else, it will turn out being the only realistic one.