Power supply not delivering correct voltages.
4 repair logs
Bang & Olufsen (B&O) — Beovision 1
This Bang & Olufsen Beovision 1 CRT TV had the audacity to emit smoke and then carry on displaying a perfect picture. A lengthy investigation eventually uncovered an X2 safety cap that had met a truly spectacular end. Came away with a cleaner TV and a great story.
Sharp — X68000 Pro II
Proper saga on this Sharp X68000 Pro II. Magic smoke from a reversed capacitor, an accidental probe short, and enough replaced components to fill a parts drawer before a single faulty transistor finally gave the game away. Got it booting and running R-Type, which was a hard-earned win. Video output later stopped working, so the story isn't entirely over.
3DO Company — Panasonic FZ-1
PSU repairs on this Panasonic FZ-1 3DO required bridging badly damaged traces, and a missed ceramic cap connection sent the console into a reboot loop. Sourcing a replacement laser meant buying a whole other console, but it runs now, and has since gained an ODE with SD card access through the AV expansion bay.
Sony — PlayStation
Don't mix PSUs with incorrect mains voltages, kids. I accidentally did that on a Sony PlayStation NTSC-J while repairing and testing the controller ports on a friend's PS1.