Macintosh Plus Platium version upgraded to 4MB

This Macintosh started my ‘hoard’ of old Apple products (Well Adrian Black started my curiosity because i like to fix old junk stuff…and he showed how easy it was).

The board from this Plus got replaced by me by a clean working version. But the original motherboard i got working in the end…

I’ve only socketted every single IC on the board. Comming to find out that the 6522 chip was broken… (One of the last ones i suspected).

Well by that i learned howto remove every IC without lifting a trace… Combination of a desoldergun/station with hotair is recommended.

I’ve used the hotair to heat the solder/melt the solder. And the desoldergun just to go pin by pin in a few seconds.

As you can see here i’ve replaced the 6522 chip with a chip from a Commodore ! And the chip next to it was ‘hotter’ than the others, so i gave it a bunch of cheap heatsinks to give it some more life. (Also i misplaced the original rom chips, so behold 27c512 chips!)

Also people say you cannot run these boards with 2 chip ramsticks… This one boots up without issues, runs benchmarks without issues and can write every memory address as far as i can test. So is it true?