[ucc] Re: Books have Arrived!

[David Emrich]

> I was under the impression that anti-theft devices worked by causing a drop
> in the strength of the magnetic field between the sensing devices, which is
> then detected by the devices. Is this right

Yes, for passive tags

> or wrong,

yes, for active tags

> or just a different way?

and yes. :-)

Some tags use "drops" in magnetic field as the actual data modulation technique from the passive tag back to the active reader.

[dav]