Thanks very much for your help, everyone.

Looks like I have a little project on my hands here, but that's a big part of the fun of this hobby.

First thing I'll do will be to check the analog board with a known good one by swapping in a logic board.

I have the other 128k as I mentioned, and a few working Mac Pluses in reserve, so I could use one of these logic boards to test.

Hopefully I can incriminate or rule out the analog board and then I'll go from there.

Also searching for "Dead Mac Scrolls" as we speak! Definitely seems too useful to not have a copy.

Thanks again and I will keep you posted on my progress.