Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!aplcen!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!mips!bridge2!ngg
From: ngg@bridge2.ESD.3Com.COM (Norman Goodger)
Newsgroups: comp.sys.mac
Subject: Re: Beware formating HD floppies in DSDD drives
Message-ID: <1408@bridge2.ESD.3Com.COM>
Date: 12 Mar 90 21:22:40 GMT
References: <1567@diamond2.UUCP>
Distribution: comp
Organization: 3Com Corp., Mt. View, CA
Lines: 37

In article <1567@diamond2.UUCP> derosa@cell.mot.COM (John DeRosa) writes:
>I have found in my Macintosh travels that it
>is possible to format HD floppies as 400K or 800K 
>in a DSDD drive (mac plus, se, II, etc).  Why, you
>might ask??  Well I ran out of DSDD and really 
>needed a 800K copy.
>BEWARE: If you now put this HD/800K hybrid floppy
>in a HD Drive (se-30, IIX, IIcx, etc), the floppy
>will be rejected with a "unrecognized disk, do you
>want to format?" dialog box.  Upon review of
>the FDHD manual (a reference of last resort) it
>says just that.
>Apple (are you listening?) this is silly engineering
>in my book, not bad, just silly.

You are assuming that this is the way that "Apple" engineered it, and that
is not the case. You are dealing with two entirely different types of
floppies from HD to 800K. HD diskettes are formulated to be more sensative
to the lower voltages that the FDHD drives use in the HD mode. When you
format and use an HD diskette as an 800 or 400K disk, the FDHD cannot
effectively overwrite the stonger signals that the previous formatting
created. I have not read of a way around this yet either. This is not
something Apple cooked up to tick off FDHD users, its just the way that
HD technology is and works. Perhaps you can blame Sony...its their drive
If I remember correctly...





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-- 
Norm Goodger				SysOp - MacInfo BBS @415-795-8862
3Com Corp.				Co-SysOp FreeSoft RT - GEnie.
Enterprise Systems Division             (I disclaim anything and everything)
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