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From: gwang@berlioz (George Wang)
Newsgroups: comp.sys.ibm.pc
Subject: Re: make your own HD 3 1/2 in floppies
Message-ID: <436@berlioz.nsc.com>
Date: 17 Jul 89 18:09:08 GMT
References: <26260@amdcad.AMD.COM> <26262@amdcad.AMD.COM> <14333@dartvax.Dartmouth.EDU> <563@amms4.UUCP>
Reply-To: gwang@berlioz.UUCP (George Wang)
Distribution: na
Organization: National Semiconductor, Santa Clara
Lines: 26

In article <563@amms4.UUCP> hjg@amms4.UUCP (Harry Gross) writes:
>
>I posted something on this a few minutes ago.  As far as I have been able to
>determine, the only difference between the two diskettes it the use of the
>flip side for data storage.  In all probability, the second side is perfectly
>fine to use.  HOWEVER, there are no guarantees that the coating is 'computer
>grade' on the flip side of a 720K diskette.  Most of the time, though, it works.

I think your understanding of the "flip" side concept arises from it's
use in computers such as the APPLE II and NOT in IBM PC's....

The IBM PC *AUTOMATICALLY* uses both sides of a diskette... So the 
double capacity difference between the 720K and 1.44 Meg diskette is
not the use of a "flip" side, nor the increase in the number of
tracks... The increase is achieved through the higher sector per track
density.... A 720K diskette has 9 sectors per track and a 1.44 meg
diskette has 18 sectors per track...

The talk of a "flip" side is out of date... These days everyone
produces diskettes that have both sides coated with magnetic
media.... Single sided 5.25 diskettes are not sold as such these
days altough 3.5 single sided disks are (though they are being phased
out too....)

George
Gwang@berlioz.nsc.com