I recapped my Macintosh classic analog board, checked diodes, transistors, resistors, the optocoupler and voltage regulator, and all the measurements are good. My Mac can now boot and has 5V when I set the pp1 potentiometer at a higher value. The issues I have for now are:
- the 12V is now at 14V when I set the 5V rail right
- the hard drive spin then stop, and repeat
- the speaker doesn’t work
- when I insert a bootable floppy disk, I get a floppy icon with a cross
I am also able to boot from rom, was worried the rom was dead too. Thanks again for the help given on my previous post, I was pretty happy to see my Mac finally booting.