Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cwjcc!neoucom!wtm
From: wtm@neoucom.UUCP (Bill Mayhew)
Newsgroups: comp.sys.ibm.pc
Subject: Re: make your own HD 3 1/2 in floppies
Summary: nothing mysterious
Message-ID: <1686@neoucom.UUCP>
Date: 19 Jul 89 15:50:55 GMT
References: <26260@amdcad.AMD.COM> <26262@amdcad.AMD.COM> <563@amms4.UUCP>
Organization: Northeastern Ohio Universities College of Medicine
Lines: 34


I've seen that advert in the back of Byte too, where they take a
whole page to descirbe a mysteious tool to convert single density
3-1/2 inch diskettes into high density.  I'd imagine that the
so-called tool is nothing more than a glorified hole punch to put
in the keying notch for density sensing.

Both 720K and HD diskettes have 80 tracks, double sided.  The
difference is that the HD diskettes have 18 sectors per track,
while the 720K diskettes are 9 sector.

I could see possibly using the notching tool to convert over
diskettes for storing things like the operating copy of one's word
processor, but I feel that it would be folly to trust the disks
for storage of original data or 1st generation back-ups.  Trusting
a questionable disk to a back-up is escpecially silly.  I know what
it feels like to blow away an article that I am working on, then
say "no sweat, I've got a back-up copy" only to find that the
back-up is bad.  For back-ups, I use good media and verify writes
carefully before I put my back-ups away.

I knew a guy that used to do the soldering iron trick to make HD
disks, he had problems that the buggered disks wold work for a
while then start to get soft and eventually hard errors.

I get the 'luxury' on my PS/2-80 of having it mistakenly format
everything as HD, ignoring the density.  To properly format 720K
disks, I have to remember to specify "FORMAT /N:9 A:", where N: is
an option switch to specify 9 sectors.  I'd be curious on hearing
from people that have clone machines, if you can force a format to
HD by typing "FORMAT /N:18". :-)  By the way, I'm using genuine IBM
DOS 3.3 on that machine.

Bill