IMSAI disks

From: Jack Peacock <peacock_at_simconv.com>
Date: Mon Aug 24 15:15:46 1998

>Two, not one, two Imsai's with Imsai disk units up for auction on ebay.

Imsai disk unit as in the original 8" Calcomp floppy? Hmm, from '76?
Be careful if it is, those drives had an extremely short lifespan (we
experienced a 300% failure rate, every drive ordered failed, and
replacements failed too). Cooling on the first Imsai floppy cabinet was
completely inadequate for 8" drives, IMSAI later redesigned it. They
sent us a cardboard baffle to try to get it to work but the only real
solution for us was to use a different brand of 8" drive. Did anyone
ever have a good experience with Calcomp floppy drives?

The controller was pretty sophisticated for it's day, used a channel
type design, you sent it basic info and it read the data into memory.
This was pre-CP/M days, we used the floppy as a sort of fast paper tape
replacement, keeping a manual directory of tracks which held code. I
patched in a crude driver to the ALS-8 assembler development ROM system
from Processor Tech to read/write memory blocks onto the floppy.
      Jack Peacock
Received on Mon Aug 24 1998 - 15:15:46 BST