Really dumb question about fuses, ratings. Still blowing fuses

Unless it is under that glob of mystery glue on that other daughter board (dont think so), no, there is no optocoupler. I can get a pic of that other daughter board but It does not look like the dimensions work to be an optocoupler. Only other chip on the boars is a 084C towards the output side.

Is there a resistor and capacitor connected in series directly to the secondary of the transformer?

Well, that gets a bit confusing because there is a total of 14 taps on the transformer. 7 on the primary, and 7 on the secondary. Of the ones on the secondary, 2 of them go to those large diodes to the side of the transformer, 1 goes to a pair of small diodes in series, then some SM resistors and such and eventually to the 2 regulators in TO-220 packages, 1 goes to R52, then to the threaded brass mount on the back (common or ground?), 1 goes to the the second largest cap and R63-R65 and make their to that lonely transistor closest to that other daughter board.

I am not sure what exactly you are looking for but I can trace one of the secondaries from the tap through a cap and to some small surface mount stuff and into that other daughter board. Let me know what specifically you are looking for and I will take a look. I still want to know what is under that glob of glue but I fear I will destroy that board trying to find out.

Just for reference, without those PS mosfets on the board, I am able to apply power without any current draw at all and I do here something "spooling up". Sounds a lot like a camera flash but MUCH quieter. Actually can barely hear it. I think it is the main cap charging up. Not if that is helpful at all.

There has to be a feedback circuit in there some where. Are you sure everything tested fine?(no shorts, open circuits, etc) I haven't encountered an smps transformer that was shorted out.

ben7 said:

There has to be a feedback circuit in there some where. Are you sure everything tested fine?(no shorts, open circuits, etc) I haven't encountered an smps transformer that was shorted out.

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It happens, but it's really VERY rare - on the odd occasions it does happen, you'll almost certainly see a fair few of exactly the same transformer fail in the same way, presumably it's not been made correctly.