13 Nov
1998
13 Nov
'98
7:45 a.m.
At 03:39 PM 11/13/98 -0500, you wrote:
2. Magnetic fields that are strong enough to overcome the coercivity
of the media. I find that refrigerator magnets, in direct contact
with low-density media (i.e. 5.25" 360Kbyte disks) will usually
result in some bad sectors. With higher-density media, which has
a higher coercivity, refrigerator magnets aren't strong enough in
my experience. And unless you put the floppy in direct physical
contact with the magnets in a PM motor or speaker, you aren't
going to cause any damage. (I've worked with floppies and hard
drives in close proximity to multi-Tesla cryogenic superconducting
magnets without any problems, so speakers and motors don't scare
me!)
Yes, that's what I was talking about. When someone warns you not
to put your floppies near magnets, particularly refrigerator magnets,
I defy them to do any damage with one. As I recall, aren't these
plasticized magnets magnetized in thin strips, and don't have
distinct "ends" like a bar magnet?
- John