Help - Norcold SCQT-6406 icebox conversion circuit board problem

[rolandcavanagh]

Hi, the 12V oscillator circuit quit, and I suspect it is the final power transistors, but can't find adequate documentation or a cross for them. The transformer and other voltages check out ok. Unit runs fine on 110V. I've found several different circuit diagrams for this model, none of which is right (and have read that Norcold used some 20 or 30 variations over the years). Original equipment on my 1986 Grand Banks trawler, currently in Vero Beach.

Anybody have an old semiconductor book to look these up?

On the circuit board in positions T01 and T02 they are each a TO-220AB package marked K532 6D on the face.

Thanks!

[mbianka]

Could be a 2SK532 Mosfets. Looks like Toshiba is one company that makes them. Here is some datasheet info:
2SK532* datasheet and application note, data sheet, circuit, pdf, cross reference, pinout | Datasheet Archive
You might also take a real good look at some of the capacitors in the circuitry. One or more may have dried out or failed and could be cause of you problems too.

[rolandcavanagh]

I suspected they are mosfets, and the package matches. Now to find some... and thanks for the advice on the caps. They look ok, but I'll try to check them when I start unsoldering stuff.