Update: I'm an idiot.
After months of going down many rabbit holes and component troubleshooting, it turned out this mac had a 220V conversion and was perfectly fine, and I was running it at 110V. Apparently when running the bulk rail at half voltage (~150V instead of ~300V) the machine still...
Great idea!
I used a rubber huse and the noise is definitely coming from the SMPS transformer (157-0130). I assume it's just physical vibration and not high voltage arcing, so safe to keep using as is?
I'll definitely try to fix it or find a replacement as I was planning to use this machine...
Hi all, first post here!
I have a Mac Classic that's making a loud sizzling/fryinng noise, but works fine otherwise. The noise disappears when I disconnect the logic board. The machine is 110v and the analog board is the 820-0525-A Hitachi version.
Repair background:
Fully cleaned and...