On Wed, 16 Apr 2003, Vintage Computer Festival wrote:
> > 2.9"
There were a couple of 2.5" and a couple of 2.9" One was a spiral track,
and one (TEC?) was the same as a 720K 3.5" (80 track, etc.)
> > 3.9"
> Who used them; who made them? Do you have a handy chart, Fred?
IBM. They showed sample drives, made by Tabor?, and disks by Brown,
before they finally went with 3.5". They showed them a LOT, and released
some "engineering samples", but never seem to have put them into a
production machine.
> > 3.5" (early ones without shutter, manual shutter, one-way shutter,
> > floptical)
> "One-way shutter"?
The original 3.5" had no shutter. The ones that I have are labeled
"Shugart".
The next ones had a completely manual shutter. YOU opened it, YOU closed
it.
Then came the "one way", or "pinch" shutter. You opened it manually, and
to close it, you squeezed the corner of the disk. A few drives would open
the disk for you, but you still needed to pinch the corner to release the
shutter to close it. Some current disks still have the arrow that points
to where you pinch it.
Then came the current style that opens AND closes it for you.
The 3.25" is a much more interesting story (Dysan bet the company on it)
At one time, the journalists were arguing about 3 v 3.25 v 3.5, as "shirt
pocket disks". MOST of them got it wrong. George Morrow had the
solution, "Let's just payoff the clothing business to make 5.25" shirt
poskets."
(Anybody got a copy of "Quotations from Chairman Morrow"?)
--
Fred Cisin cisin_at_xenosoft.com
XenoSoft http://www.xenosoft.com
Received on Wed Apr 16 2003 - 20:59:00 BST