My first Apple computer, a Mac IIcx

joshc

Well-known member
UM5 - looks like an Apple specific clock IC
UM5 is the Apple 'Real Time Clock' (RTC) chip. Looks like yours may still be OK - as long as the legs are not completely corroded away, they may just need some cleanup with vinegar and possibly sanded a bit to bring them back.

Y4 - presumably a crystal for the clock
Y4 a crystal, its on page 4 of the Bomarc schematics.

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F3 - a fuse?

F3 is a fuse, it's for the internal/external floppy I/O. F1 and F2 are on the Bomarc schematics as SMD200 2A.
 

rodders

Active member
Well, I can't believe its been a year but I've finally got round to tackling the IIcx. I managed to revive the basket case RiscPC I was working on (that was a journey) and then got distracted by an A3020 and an Amiga but the IIcx now has my full attention.
The logic board has suffered from cap leakage and battery damage quite severely but it looks like it was stored on its right side so the alkali from the battery hasn't gone through the RAM. The startup circuit is toast with several components falling off and I've discovered lots of eaten traces on the back of the board.
I've also taken the PSU apart and lo and behold, one of the Rifas has exploded. Collective wisdom seems to be that its not worth trying to restore the (Astec) PSU so I've ordered a Flex ATX and plan to drop that inside the Astec box.
The floppy drive is full of crud, not surprising as its the main air intake. Not sure if its saveable yet.
I'll post some pics if anyone is still interested.
 

Snial

Well-known member
Well, I can't believe its been a year but I've finally got round to tackling the IIcx.
Cool, I once had a IIcx in the very late 90s.
and then got distracted by an A3020
Who wouldn't? I decided to spend a week or 2 converting a PS/2 mouse to a Quadrature encoded mouse for my A3020!


The HD died a while back, so I need a suitable cheap replacement (a DOM disk I think!). Also, I want to connect my Parallel Port Zip drive to it!

and an Amiga
An A600 was always on my list, but instead my most recent acquisition was a CPC464!
 
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