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Re Drives again: I forgot to mention that the machine came with a funky little adaptor board attached to J4. No idea what it does. See attached images:

It's a home-made 8" floppy interface board. You may want to keep it just for fun, in case you ever come across an 8" drive.

Dave

Just a quick update on the C24P.
I was messing around with the serial connection on this machine, and I discovered that the serial out line was not working.
I traced the dead signal back from the DB25 serial connector to the 2N5226 transistor where the the pulsing signal returned. After some head scratching and probing around this area I was fairly confident that the problem was indeed the transistor itself. With my trusty Hakko 808 I quickly removed the transistor and dropped in a new one...to my surprise the serial out still did not work.
After sharing a few off forum emails with Dave on the subject he hit upon a possible solution. He mentioned that there is a jumper that can either select GND or -9V for in the TX circuit. On closer inspection of the board I found the cut trace and the jumper wire connection to the -9V line. I reversed this back to the GND line as I don't have a -9V power source anymore as I am using a modern switcher power unit, and presto, the serial output now works. Well that was a quick summery of what actually took me 4 evenings to figure out.
Thanks again Dave.