Would the tags work only if the second piece were inserted into the first?
I have seen tags for which a piece of antenna could be removed so the tag would not function anymore, but I have never seen a tag for which you would add a piece of antenna to enable the tag to work. Theoretically, you could build a tag with a tiny antenna that would enable it to be read only at a distance of few inches. By adding an extension to the antenna, you would enable it to read the tag at a much longer range; the exact amount would depend on the design of the piece added. You would need to work with a tag manufacturer to develop and test this system, but I think it might be feasible. If any of our readers know of any tags like the one you desire, they are invited to post information below.
—Mark Roberti, Founder and Editor, RFID Journal
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