Demagnetizing
Buford Terrell
terrell at sam.neosoft.com
Sun Aug 27 13:41:18 PDT 1995
>Reply-To: dr261 at cleveland.Freenet.Edu (Tobin T Fricke)
>
>Where exactly is the r/c circuit? Is it very small and in
>a label? Book publishers don't put them in, do they?
>Also, if the thing gets "burned out" by the magnet in the
>pad, what do libraries and such do where materials are
>reused? Just slap on another label thing?
>
It's much more low-tech than that. Libraries and book stores just
put a strip of magnetized material (it's much like audio tape,
about 1/8 inch wide and comes on rolls) inside the book and then
put detectors at the doorway. It the detector feels a magnetic field,
it buzzes; if the tape has been deguassed, nothing happens.
For libraries, it's usually mounted on sticky tape and put down
inside the book spine. Bookstores usually just snip off a 4 - 5"
segment and slip it inside the book. Music stores frequently tape
a small section on the outside of CD jewel boxes.
Sorry, there's no real mystery or exciting tech here.
Buford C. Terrell 1303 San Jacinto Street
Professor of Law Houston, TX 77002
South Texas College of Law voice (713)646-1857
terrell at sam.neosoft.com fax (713)646-1766
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