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What type of security tag is this? Answered

Could anyone tell me what type of security tag this is?
I have Googled and Wickipediad en.wikipedia.org/wiki/Security_tag 
around the subject looking for,  'induction coil security tag',  but I mainly find information about the flat strip type.

I'm new to electrickery so I am guessing it is an induction type of device?
Also, is the green component a capacitor?

Thank you.


Its not an ACTIVE tag, its a PASSIVE tag. Its designed to cause a detector to get upset when the tag is near it.

The detector is a tuned circuit, oscillating at a fairly high frequency. When the tag nears the detector, it increases the losses in the detector and triggers an alarm.

Really simple.


Hi, an old question now but just in case you are still wondering....

This certainly appears to be a tag - but an incredibly heavy duty one and also one which appears to have been made to operate at a very low frequency (hence many turns of wire over what looks like a ferrite rod).

Usually re-usable tags consist of about 7 turns of copper wire roughly 40mm in diameter and with a 100pf capacitor going from one end of the coil to the other.

Make that up and walk through most shops gates and they will go beep at you :)

The ones above are normally running at a few Mhz - IIRC - but your device looks FAR more likely that it has been designed to operate in the KHZ range.

I would guess it makes it much more capable of operating over a longer range (outdoor sales area at a fair??). Certainly it is an expensive component (compared the the usual couple of foot of wire and a 1p capacitor.

The green thing is indeed a capacitor - and not only that the value is 1n2

(101 = 100pf 102 = 1n 103 = 10n 121 = 120pf 122 = 1n2 123 - 12n)

Kind Regards


Are you sure it's a security tag? Did you remove it from a plastic housing or something that was attached to store merchandise? Possibly a description of what you found it in would be helpful in identifying it. As is, to me it looks more like part of an electric motor or a guitar pickup than a security tag.

Thank you both from RavingMadStudios for replying.

I seem to recall opening up a light grey security tag ,( that had been left on something from a shop), and all that was inside was this ... my recollection is not always the best but it seems like a clear memory... it is possible  that I'm wrong, in which case I apologize for wasting your time.  

Best Wishes

.  My guess is that it's an inductor or part of a solenoid. Also guessing that the green thing is a capacitor to absorb spikes when you turn the coil off.
.  I'm with RavingMadStudios - need more info and it sure doesn't look like a security tag.