One of my PP-7Bs seems to have died about a week ago as well. Isolation transformer is still fine, but the PS unit itself won't power PCBs. Just spontaneously crapped out (after being on continuously for about a day).
Of course, this came a week after I accidentally caused a short in a PCB I was poking at (after which I smelled that "burny electronics" scent from the PS) so I blame myself. It sill worked fine for a few days, but I guess the damage had been done...
From what I hear, you can do a cap kit on the PP-7Bs, but new capacitors might not fix it because they might not be the problem. Might be a transistor or who knows what else.
Consensus from what I've seen seems to be that parts are hard to find, and overall they're more trouble than they're worth. Everyone just says to replace it with a switcher and use the Arcade Shop PS adapter.
Honestly though, probably just cheaper to buy one of the originals from somebody on KLOV, plus, with the switcher/Arcade Shop solution the coin meter doesn't work (no +24v), and if you're like me, you like to have the coin meter working.
