On Sep 24, 14:24, Joe wrote:
> I'm still trying to find out where the 2.4Mb 5 1/4" floppy drives came
from.
> The sled has IBM PN 25F8398 on it. I've searched Google and IBM's site
for the number but didn't find anything. I found these drives in the same
pile with some IBM RS/6000 cards. Does anyone know if the RS/6000 uses
anything like this?
I'd never heard of a 5.25" 2.4MB floppy before this, but I know that some
models of the RS/6000 range and I believe also some PS/2 range had
so-called "2.88MB" 3.5" floppies. I have one here (the drive,that is, not
the RS/6000). They look just like ordinary 3.5" HD floppies except for the
extra media sensor. They can use normal DD or HD disks, or special ED
disks which have the media sensor hole in a different place to HD disks --
it's slightly further from the bottom edge, so if you put an ED disk in an
HD drive, it would be seen as DD. However, the coating is a special barium
ferrite rather than the normal cobalt ferrite, and for ED, the drive uses a
vertical recording technique developed by Toshiba instead of normal
longitudinal recording. If the disk in the drive you've found looks just
like a normal HD floppy, that's what it is -- not an Extra Density one.
Apart from IBMs they were also used in 3Com Netbuilder routers.
--
Pete Peter Turnbull
Network Manager
University of York
Received on Tue Sep 24 2002 - 18:43:00 BST