Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!bionet!apple!voder!parns!berlioz!gwang
From: gwang@berlioz (George Wang)
Newsgroups: comp.sys.ibm.pc
Subject: Re: make your own HD 3 1/2 in floppies
Message-ID: <435@berlioz.nsc.com>
Date: 17 Jul 89 17:53:52 GMT
References: <26260@amdcad.AMD.COM> <8020020@hp-lsd.HP.COM> <8649@attctc.DALLAS.TX.US>
Reply-To: gwang@berlioz.UUCP (George Wang)
Distribution: na
Organization: National Semiconductor, Santa Clara
Lines: 23

In article <8649@attctc.DALLAS.TX.US> wnp@attctc.Dallas.TX.US (Wolf Paul) writes:
>I would be very much interested in a discussion of the magnetic properties
>of 360K, 1.2M, 720K and 1.44M diskettes, respectively. Apparently, the
>surface difference between double and high density 3.5" diskettes is NOT
>THE SAME as the difference between double and high density 5.25" disks.
>
>

Correction! There *IS* a difference in the magnetic media of
3.5 High Density and Low Density diskettes... If you examine the
medias of NAME BRAND diskettes you will notice a visible difference
in the media of low and high density 3.5 diskettes... Furthermore,
high density drives write in a lower signal level than low
densities...

Perhaps bulk-quality disk companies who claim that there diskettes
are high density certified are using the same "hole punch" trick...
But Name brand diskette companies such as 3M produce diskettes
that do *NOT* have the same media surfaces... The same difference
exists in 5.25 diskettes...

George
Gwang@berlioz.nsc.com