Exaggerating about the number of posts. But from here on, I'll number them so that anyone intersted can follow along in order. It's not impossible that some other unqualified person might have a similar piece of equipment and might pick up a little something from my aimless attempts to find the problem.
If you're a new reader of my saga, I'm attempting to repair a wine cooler with thermo-electric coolers (2) with a power supply for each, and a common break-out board. Every capacitor, every transistor, every resistor, every IC, has been replaced with new. The only things not replaced would be the three transformers. I've not been able to find matches for them. And replacing the boards entirely does not seem to be an option at any price. And even though it might not seem so to you guys with know-how, I am actually attempting to be systematic about the whole thing.
In their current state, neither power supply will produce the 12.5v they are rated for. One will put out 11 volts, the other one ten. And in each case-- the voltages stated are without any load. Each load (cooler, fan, etc.) diminishes the output voltage so that it ultimately goes down to almost nothing. I know there's a clue there, but not for me.
Today's question is in the form of measured voltages at discrete locations hoping that one of you might be tipped off as to what's going on. My measurements are taken from the two rectifier outputs and the collectors from each of the two transistors. I have attached pics as well as the schematic. Thanks for any help.
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