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Classic I seeks floppy on boot


Well-known member
I have a Macintosh Classic I which has been recapped, logic board and the analog board.

After recapping the logic board I tested it. The thing booted up as it did prior. I moved on to the analog board as the CRT was just a bit wobbly. While testing after that recap it will seek the floppy drive with no disk in it. After booting to finder it reports an unformatted disk in the drive and you can't really move past that. If I remove the floppy cable from the board it all worked fine.

My -12v rail is spot on. +12v is more like 11.5 and 5v is 4.7v. While working on the analog board I replaced the optoisolator and DP5 and DP5 near the optoisolator.

Any thoughts on where to go next?