Hi. Yes, this is my first post. I mostly joined because searches for various things I want to know tend to bring me back to here.
I've started a project to bring as many of my old machines back and make them healthy as possible. Oddly, most of my ailing ones are Apple.
I've been trying to tackle the Seasonic PSU that came with a categorically messed up II+ clone I picked up over 20 years ago. Long story short. The Motherboard works again. The keyboard won't work until I remove the chips and give it a new brain. The floppy controller needs a repair, along with one of the floppy drives. Not sure about the rest.
The PSU may have been what wrought the havoc in the first place. I vaguely remember it being super unstable before it died.
Skip to present. I've pulled and checked all the caps. Some of the resistors and diodes. Repaired a couple of scratched traces. It works. Or at least the +5 and +12v rails do. It can happily power my dummy load of two WD Caviar drives. The -5 and -12 are sad. -12 is around -4.x volts, and -5 is +2.x volts. My gut is telling me something about a ground reference but apparently I'm not smart enough to understand it.
In the attached photos, there is a solder bridge between one of the power transistor bolts and a track. There was a gouge there. It was the deepest part and there was some minor damage to a nearby track. After asking elsewhere online it was mentioned it could have just been a sloppy factory mod. So I removed the bridge again before testing it. Also I have no idea what the deal is with the resistor on the underside of the board.
I flipped the PCB side and aligned the top and bottom photos as best as I could for position and perspective.
Please, ask away if more info is needed. There's really no reason for me to use this PSU instead of replacing it with an ATX beyond me wanting to. Same as the rest of the clone really. I just want it to work again.
edit: I have absolutely no idea what I'm doing with the photos. Sorry!