Osborne 1 disk drives (was RE: 5.25" floppy model numbers)

From: Feldman, Robert <Robert_Feldman_at_jdedwards.com>
Date: Fri Mar 29 09:11:42 2002

Osborne also replaced the electronics on the drive with their own board. My
O1 had Siemens FDD 100-5 drives.

I have the cable pinout and disk controller schematics in my copy of the
Osborne 1 Technical manual, if anyone wants a copy.

Question: the tech manual says that with the double density option
installed, the O1 could read/write IBM 40 track 8 (512 byte) sectors, Xerox
820 40 track, 18 (128 byte) sectors, and DEC 1820 DD 40 track 9 (512 byte)
sectors. Can anybody verify this (Fred?)?

-----Original Message-----
From: Don Maslin [mailto:donm_at_cts.com]
Sent: Thursday, March 28, 2002 3:48 PM
To: classiccmp_at_classiccmp.org
Subject: RE: 5.25" floppy model numbers




On Thu, 28 Mar 2002, Erik S. Klein wrote:

> Before you scrap them?
>
> I'm looking for some old 5.25" drives to bring back a couple of Osborne 1s
> to dual drive status.

Be advised that the Osborne drives are not directly interchangeable with
`normal' 5.25" drives. The ribbon cable to the card edge carries drive
power as well as signals and is wired differently. You will need to
conjure an adapter to use normal ones.
                                                 - don

> Does anyone know of a good source for old floppy drives? Or better yet, a
> source for getting them repaired?
>
> Erik S. Klein
<snip>
Received on Fri Mar 29 2002 - 09:11:42 GMT