Forces from such drops cannot modify the magnetic particles. This inaccurate
and unverified rumor is echoed by Cade Metz in a hard drive article on page
133 of the February 7, 2005 issue of PC Magazine, where he also incorrectly
states that "1" and "0" bits are represented by specific magnetic
orientations (channel bits, not data bits, are recorded, and "ones" are
represented by transitions, not the polarization direction). Beware of
"experts".
Drops can damage the cassette, or can induce dropouts on the tape itself if
the pancake shifts and interlayer trapped particles abrade the coating.
Other effects may also occur, but changing the magnetization of high
coercivity magnetic particles requires intense magnetic fields.
Jerry
Media Sciences, Inc.
-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:ARSCLIST@xxxxxxx] On Behalf Of Konrad Strauss
Sent: Wednesday, January 11, 2006 10:14 PM
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: Re: [ARSCLIST] Risk assessment tool Q3--DAT
on 1/10/06 7:02 PM, Tom Fine at tflists@xxxxxxxxxxxxxxxxxxx wrote:
> 1. drop a tape and watch out for data dropouts. Just like a U-Matic and
to a
> lesser extent a VHS video cassette. Dropping a DAT can and usually does
> scramble the magnetic particles in one or more parts of the tape.
Digital
> dropouts are about as graceful as video dropouts.
This is news to me. I used DAT regularly for at least 12 years and must
have
dropped and otherwise abused a hundreds of them. I cannot ever recall a
dropout which I attributed to a dropped DAT. What is your source for this
information?
> 2. magnetic media, with actually quite dense storage-per-square-inch,
subject
> to all the erasure and deterioration problems of other magnetic media.
I'm not
> sure what happens to DATs as the signal fades -- has anyone had any
experience
> with this?
Do you have any more information on this? I have never heard of a signal
fading on magnetic tape.
--
Konrad Strauss
Director of Recording Arts
Associate Professor of Music
Jacobs School of Music
Indiana University
http://php.indiana.edu/~kstrauss
http://www.music.indiana.edu/department/audio/