Fun with degaussers - test-drb@ccmp.vtda.org

2 May 1999

...
 > >This sounds like voodoo to me.  There must be
some point when you are
> >lifting the demagnetizer away that the effects from the device are
> >beneficial.
> 
> The "lift it slowly away and then turn off" is an important point.
> This makes sure that the media really is demagnetized.  If you turn
> it off while near the media, you can leave the media in a highly
> magnetized state. 
...
 So then is that all that's really required? 
The "rotate around at many different orientations" is also
important for a thorough degaussing.  Unlike electric charge, which
doesn't have a direction, magnetization *does* have a direction.

The really professional degaussers will automatically rotate and diminish
the magnetic field in a pre-programmed sequence.  These are very large,
however, and cost lots more dollars than the ones you buy at Radio Shack.

With many modern high-coercivity media, you can't do a really thorough
job of degaussing with a small degausser in any event.  They just don't
make a large enough field.

-- 
 Tim Shoppa                        Email: shoppa(a)trailing-edge.com
 Trailing Edge Technology          WWW:   http://www.trailing-edge.com/
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