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Re: anti-theft strips



At 00:19 3/12/99 -0800, you wrote:

Anyone out there know just how those anti-theft strips that are often
inserted in books, or attached to CDs. etc, work? I've taken a few
apart, both inside and outside the store, and found they are all what
appears to be a very small capacitor with one obviously metal plate,
and the other plate, well, at least it is metal like. Electret? In
anycase, if they are tightly squeezed together (the plates, that is)
they don't work.

Particularly, how is it that they are so easily desensitized?
...
Leon

Apparently one version has a non-linear diode-like component that
responds to a search beam with a faint second harmonic.
That's all I have.

Brian

brian whatcott <inet@intellisys.net>
Altus OK