Well, it's not the ADB filter. I swapped it out with one from a IIgs, and same issue. Auto-power on an no ADB ports. The same symptoms listed above.
That does look like a nice fix! As an aside, I had also replaced the small diodes and transistor on my soft power circuit, not sure it was necessary (and not saying it might be a factor for you) but it's crazy how much that cap goo spreads and what it eats. With regards to the continuous turn-on problem) I'm sure you removed the jumper wire from the PSU plug? (I have to ask as sometimes it's the most obvious thing).@superjer2000 OK, some interesting developments. I replaced all three 3 ICs and ran a bodge wire from a missing pad (it had completely corroded away.)
Great news is that the computer now turns on. Yay! Bad news is that it always turns on no matter what. It's like I have the power switch on the rear pressed in. However, after it boots, neither of the ADB ports work. Some Lycosing indicates that non-working ADB ports is a bad ADB filter.
So back when I thought the filter could be bad, all the shorts disappeared when I removed it. So now I'm leaning back towards a bad ADB filter. It didn't occur to me that the filter is bunch of capacitors, and mine is completely shorted open. Fortunately my IIci has both DIP holes and IC pads for a filter. So I think I can steal a filter from another computer with ADB ports, it doesn't have to be the DIP version. I'll try swapping out the filter tomorrow and see how it goes.
I'm hoping I can just buy a generic filter, but I don't know what part to look for. I couldn't "find an alternative" on Digikey or Mouser.
In the meantime, I'm pretty happy with my rework. Especially my bodge wire. I got a nifty metallic blue teflon wire from the recycler. My handy work is all hidden under the power supply, though.
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