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- From: warren@wam.umd.edu (the stupid one)
- Subject: Re: How to Erase a Floppy without Computer (was: Pizza Hut erases diskettes)
- Message-ID: <1993Jan12.175715.29402@wam.umd.edu>
- Sender: usenet@wam.umd.edu (USENET News system)
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- Organization: University of Maryland, College Park
- References: <1993Jan1.234107.1@vms.ucc.okstate.edu> <1993Jan2.142927.14517@cbfsb.cb.att.com> <bern.726852282@kleopatra>
- Date: Tue, 12 Jan 1993 17:57:15 GMT
- Lines: 26
-
- thus spake bern@Uni-Trier.DE (Jochen Bern):
- >Alternating magnetic Fields: This gets more dangerous. Alternating Fields
- > are able to penetrate through Materials which might filter out static
- > Fields. See below.
- >
- >Mailing Floppies: Since there are other Dangers to a Floppy when it gets
- > sent by Mail, it is probably wrapped into several Layers of whatever
- > Material. This is good enough to ward off static Fields, I think; Those
- > famous two Subwoofers maybe excepted. Designated Floppy Mail Enclosures
- > often include an Aluminium Plate in Order to require Arnold the Postman
- > to bend or fold them. :-) If I'm not very much mistaken, this Plate
- > might protect the Disk even if it's on the OTHER Side of the Disk
- > since Aluminium "pushs back" magnetic Fields (can somebody please
- > check this?). As mentioned by others, 3.5" are generally harder to magne-
- > tize than 5.25".
-
-
- this is backwards
- any conductor will provide some protection from alternating fields
- it would take a suuperconductor to provide shielding from static fields
- unless the container is ferromagnetic like iron
- but then you run into problems with possible fields from the shielding
- and ferromagnetic materials tend to be heavy
- --
- We now return you to our regularly scheduled programming,
- already in progress...
-