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From: johns@happy.uk.sun.com (John Slater)
Newsgroups: comp.dcom.telecom
Subject: Re: Two Cellular Phones, Same Number
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Date: 14 Jun 90 16:56:28 GMT
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In article <8865@accuvax.nwu.edu>, rees@dabo.ifs.umich.edu (Jim Rees)
writes:

>Can anyone tell me how the British card works?  On the French card you
>can see the electrical contacts, but the British one doesn't seem to
>have any.  Is it done electromagnetically?  Or with mirrors?

I used to know this. I seem to remember it's got something to do with
application of heat to the card. The card itself is read magnetically,
but when a particular 10p unit has been used it is disabled either by
a laser or by local heating.

I may be totally wrong. I'm sure someone will correct me if I am.


John Slater
Sun Microsystems UK, Gatwick Office