Library Store Scanners: Info & How They Work

[Moose352]

If anyone has been to a library or a store, they have scanners at the entrances that set off an alarm when someone goes by with a stolen product. Anyone have some more information about how these work or what they are called?
Thanks

 

[Integral]

A strip of magnetic material is impeded in the books or tags on merchandise. The detectors sense the presence of this strip.

 

[KingNothing]

Its the same with DVDs and CD's at my workplace (target). We have to run them over this black magnetic strip thing when we check people out, so the detectors don't go off. Not to imply that we have some sort of security that would do anything about it. *chuckle*

 

[chroot]

The stores use little devices called EAS (Electronic Article Surveillance) tags. You can learn a lot about them by searching on google. Here's a good site to get you started:

http://www.aimglobal.org/technologies/eas/easoverview.htm

The tags you'll encounter most frequently are the acousto-magnetic types.

- Warren

 

[Moose352]

Thanks for the replies. I know most implementations use some type of magnetic sensors. But at my school library, I am quite sure that they do not run the magnetic strip (on the book) through anything, which perplexes me. I'll have to do some more investigation...

 

[chroot]

Often the de-arming device is built into the checkout counter. All the attendant has to do is lay the book on the counter to deactivate the tag.

- Warren

 

[john54]

The stores use little devices called EAS (Electronic Article Surveillance) tags. You can learn a lot about them by searching on google. Here's a good site to get you started:

http://www.aimglobal.org/technologies/eas/easoverview.htm

The tags you'll encounter most frequently are the acousto-magnetic types.

- Warren

thank you!

 

[Loren Booda]

Recently I've noted what appear to be flat, inductive coils (as opposed to magnetic strips) on a patch attached to the item. How does the store disarm one of those? (I couldn't get through to the above suggested site.)

 

[john54]

(I couldn't get through to the above suggested site.)

Me too.

I've searched google and find it difficult to get answers to the following questions. Would anyone kindly answer them here?

1. What kind of waves (?) is received by the receiver?
2. How can the receiver identify the theft regardless of the orientation of the tape?

thank you very much

 

[Loren Booda]

An E-M signal at the door can make the inductive coil resonate, like one of the best bugs once created by the USSR.