Path: utzoo!dciem!nrcaer!cognos!bdeskin
From: bdeskin@cognos.uucp (Bob Deskin)
Newsgroups: comp.sys.atari.st
Subject: Re: SS disks
Message-ID: <2973@cognos.UUCP>
Date: 10 May 88 12:40:06 GMT
Article-I.D.: cognos.2973
Posted: Tue May 10 08:40:06 1988
References: <184chad@byuvax.bitnet>
Reply-To: bdeskin@cognos.UUCP (Bob Deskin)
Organization: Cognos Inc., Ottawa, Canada
Lines: 39

Newsgroups: comp.sys.atari.st
Subject: Re: SS disks
Summary: 
Expires: 
References: <184chad@byuvax.bitnet>
Sender: 
Reply-To: bdeskin@cognos.UUCP (Bob Deskin)
Followup-To: 
Distribution: 
Organization: Cognos Inc., Ottawa, Canada
Keywords: 

In article <184chad@byuvax.bitnet> chad@byuvax.bitnet writes:
>
>Question: Is it true that MACs use the top of the disk while Atari/IBM
>use the undersides?  If that is true, then all SSDD disks are *certified*
>DSDD disks as the manufacturers wouldn't know which computer is going
>to be used and therefore which side to certify...
>
>That is what I have heard.  If it is true, then it is the biggest scam
>around.

What you say may be true, however, as I understand it, there is no 
question about whether both sides of a SSDD disk are usable, its whether
both sides can be used with assurity at the same time. Again, as I 
understand it, a DSDD disk has a slightly thicker platter so as to 
separate the two sides more. This prevents interference when reading.
Remember that reading a disk means electronically reading the magnetic
encodings. If, when reading the top side, you pick up the bottom, well, 
you are going to get garbage. I have heard of many people using SSDD
disks as DSDD without difficulty, but they make sure they have backups.



-- 
Bob Deskin		decvax!utzoo!dciem!nrcaer!cognos!bdeskin
Cognos Incorporated	P.O. Box 9707
(613) 738-1440          3755 Riverside Dr. 
			Ottawa, Ontario, CANADA, K1G 3Z4