Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!cs.utexas.edu!hellgate.utah.edu!cs.utah.edu!t-jacobs
From: t-jacobs@cs.utah.edu (Tony Jacobs)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Drilling holes in DS/DD -> DS/HD
Message-ID: <1989Dec15.131138.1284@hellgate.utah.edu>
Date: 15 Dec 89 20:11:37 GMT
References: <16918215MES@MSU> <89347.194237CXT105@PSUVM.BITNET> <2427@loral.UUCP>
Distribution: usa
Organization: University of Utah ME Dept
Lines: 24

In article <2427@loral.UUCP> art@loral.UUCP (Earthman Arthur Donavan) writes:
>For what it is worth;
>
>I have read a magazine article concerning holes in disks to make them HD
>disks.  The standard media has a magnetic coating of about 600 oersteds,
>and the HD media has a 700 oersted coating.
>
>Maybe there is some magnetic engineer out there in netland that can shed
>some light on the difference, and if the difference is great enough to
>worry about lost data. (Bits changing states, etc.)
>

My BS in ME & MS in EE roomate says if gauss is analogous to current then
oersteds is analogous to voltage. He doesn't think that the oersted count
should have any effect on how long it holds onto the field. It might mean
it takes a little more to magnitize it and that it has a little stronger field
once magnified.

One question I'd like to know is if the High Density drives have more tracks,
more bits per track or both.



Tony Jacobs * Center for Engineering Design * U of U * t-jacobs@cs.utah.edu