Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!husc6!spdcc!ima!johnl
From: johnl@ima.ima.isc.com (John R. Levine)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Are 720K floppies really 1.44M in disguise?
Message-ID: <3284@ima.ima.isc.com>
Date: 5 Feb 89 19:08:24 GMT
References: <1140@ccncsu.ColoState.EDU>
Reply-To: johnl@ima.UUCP (John R. Levine)
Distribution: usa
Organization: Segue Software, Inc.
Lines: 18

In article <1140@ccncsu.ColoState.EDU> miker@csupwb.colostate.edu (Mike Riley) writes:
>[People claim that 720K and 1.44M floppies are really the same.]

The oxide on 720K disks and 1.44M disks really is different.  That said, I
find that more often than not I can format 720K disks as 1.44M and they work
perfectly well.  I don't keep anything I really care about on those disks,
since the chance of losing the data is somewhat higher than otherwise.

The gizmo advertised in Byte and other magazines is really just a hole punch.
There is a hole in the corner of real 1.44M disks so that the drive can tell
what kind of disk it is.  On most 1.44M drives (other than IBM's) it won't
let you treat a disk without the hole as 1.44M.  I'm sure that the hole punch
works, but I'm not putting my important backups on disks run so far out of
spec.
-- 
John R. Levine, Segue Software, POB 349, Cambridge MA 02238, +1 617 492 3869
{ bbn | spdcc | decvax | harvard | yale }!ima!johnl, Levine@YALE.something
You're never too old to have a happy childhood.