Hi,

It could be the flyback, because my Mac Plus had an unstable screen (jittering), that would come and go every so often (it was worse when it was cold). Anyway, I left the room for a bit, and when I came back, the place smelled of burnt electronics and the Plus's screen was blank. I sniffed around for the source of the smoke, and it was the poor Plus. I opened it up, and discovered that the flyback had blown, taking with it a transistor. I replaced both, and it works fine now, but it was kind of scary since I thought it was ruined.

Anyway, this story isn't meant to scare anyone; I was just trying to relay some anecdotal information which someone will hopefully find useful.

c