Subject: Re: 3-1/2" Floppy Market Cornered

From: chris <[email-masked]>
Date: Tue May 20 22:13:00 2003

>I thought you could use 3.5" HD/DD disks in a DS/DD drive just fine.  At
>worst a piece of tape over the "wrong" hole if necessary. 

At least with the Mac, this isn't a good idea for long term use. It will 
sometimes format the disk as DD if you tape over the HD sense hole, but 
even if it does, you can pretty much count on the disk failing in a very 
short period of time. I've never had a disk last more than a few 
read/write sessions. After that, errors start occuring and you can't read 
or write to it any more. 

In many of the cases, the disk is usually hosed after this and won't take 
a format back to HD anymore.

I can't say that I've really tried it outside of a Mac, so it might just 
be a Mac thing that keeps it from working.

And despite the fact that some company made a hole puncher to make DD 
disks into HD disks (I have one), that doesn't seem to work any better on 
the Mac. In fact, in my findings, it works even worse as it rarely ever 
even took the HD format in the first place, and when it did, it 
immediatly starting having R/W errors and was unusable anyway.

-chris
<http://www.mythtech.net>

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From: Joe <[email-masked]>
Date: Wed May 21 07:47:00 2003

>a format back to HD anymore.

   This has been my experience with PCs as well. I might be wrong it seems
like the older disks and PCs worked better but the newer ones seldom work.

   Joe

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From: "Fred Cisin (XenoSoft)" <[email-masked]>
Date: Wed May 21 12:53:00 2003

"360K" diskettes are 300 Oersted.  That is a measurement of magnetic
coercivity.  If you have no idea what that means, think of it as being
like film speed in photography.

"1.2M" diskettes are 600 Oersted.  That is way too different from 300
Oersted for interchange to work in either direction with
"360K" diskettes.

"720K" 3.5" diskettes are 600 Oersted.

"1.4M" 3.5" diskettes are about 750 Oersted.  

600 and 750 are close enough that you can almost get away with it.  You
can turn a good diskette of one into a crummy diskette of the other.

What part of that is hard to understand?
I especially liked the old ads for the punches, particularly the ad where
the guy could "PROVE" that the diskettes were the same, because he had
measured them with a micrometer.

> a format back to HD anymore.
Fortunately, there is no damage that formatting can do that can't be
undone by bulk erasing.

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From: David Holland <[email-masked]>
Date: Wed May 21 13:40:00 2003

That clarifies it..

Gee, more junk my wife will love me for wanting to buy. :-)

Thanks, 

David