8-inch drive substitutes
tshoppa at wmata.com
Fri Oct 20 14:23:38 CDT 2006
From: "David Griffith"
Subject: 8-inch drive substitutes
> I recently sold a Qumetrak 842 8-inch floppy drive to a fellow who's
> restoring a CMI vintage synthesizer. He says that this particular
> is what the synth uses. Can anyone think of a reason why he couldn't
> some other model of drive as long as it's capable of reading DSDD
Stepping rate and head-load timings will vary between drives.
Sometimes dramatically (e.g. Persci's!)
Jumpering of drives for things such as drive ready, disk
change, etc. can get hairy unless you have documentation
for both the "original" and "target" drives. Jumpering
details can vary between different board revisions. Often
transliterating the jumpering needed is easy; other times
you think you did it right but there are gotchas you don't
see until you look at schematics or pull out your scope.
In industrial uses sometimes you see door-lock and
disk-eject solenoids - available on many models but
not commonly found in many circumstances. (These
are also options on some 5.25" and 3.5" drives...)
Some drives are capable of remotely spinning up and down.
As Nico mentions, some use 50Hz AC for the drive motor,
some use 60Hz AC for the drive motor, and others run the
drive motor from the +24VDC.
And as Nico alludes to, some need just +5/+24V and others
need some negative power supply for the electronics
and others need line AC for the motor.
Often the drive itself is behind some panel/bezel and the
holes in the panel must match the holes in the drive :-).
Some drives are distinctly non-standard in terms of
dimensions, even if they come from "standard" manufacturers
(there were some weird-ass Shugarts out there.)
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