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From: saa33413@uxa.cso.uiuc.edu
Newsgroups: comp.sys.apple
Subject: Re: 5.25 floppy disk formats
Message-ID: <113300202@uxa.cso.uiuc.edu>
Date: 1 Dec 89 22:35:00 GMT
References: <8911301932.AA18989@apple.com>
Lines: 46
Nf-ID: #R:<8911301932.AA18989@apple.com>:-30:uxa.cso.uiuc.edu:113300202:000:2520
Nf-From: uxa.cso.uiuc.edu!saa33413    Dec  1 16:35:00 1989


/* Written  1:31 pm  Nov 30, 1989 by ATKINSON@RUBY.VCU.EDU in uxa.cso.uiuc.edu:comp.sys.apple */
/* ---------- "5.25 floppy disk formats" ---------- */

Query: Has the following ever been discussed?

I like 3.5 diskettes, but even with 3rd party, its awlfully expensive
to start up. My idea was for a controller to read/write the
DDDS 5.25 360/720k diskettes.  I tend to like a disk per subject, and
the 720k is about the length of my subjects ( and attention span).

Is such a beast available? If not, why? And if this discussion has
already happened, what dates so I can try to get them out of the archives?

Luther
Atkinson@vcuvax for bitnet
Atkinson@ruby.vcu.edu for internet.
/* End of text from uxa.cso.uiuc.edu:comp.sys.apple */

A while back (early 1986 or so), there was a product called EquiDisk Plus.  It
was made by a company called (I think) HM Enterpises.  I'll check my back
issues of Nibble and get back with you ASAP on that.

Anyway, the EquiDisk Plus was a dual-5.25" drive unit.  I imagine it used
DSDD drives with a special controller to deliver 737K on an ordinary 5.25"
disk.  Chances are the 3.5" drives put out by Apple (and, later, by other
companies) drove the EquiDisk off the market.  I don't have one, but they
had an excellent idea.  The cheapest I've seen 3.5" disks is $0.99 each.  I
can get 5.25" disks for $.21 each.  5.25" is much more economical.

Now that the EquiDisk is no longer with us, what you're talking about is
probably an even better idea.  Existing Apple drives (Disk 5.25, DuoDisk,
maybe even the venerable Disk II) probably could handle double density,
at least.  You could only go up to 560K this way (280K per side), but 
anything's an improvement, right?  Of course, this controller would also have
to be compatible with the existing 5.25" 140K format.

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