User talk:Congruence

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[edit] Welcome to Wikipedia!!!

Hello Congruence! Welcome to Wikipedia! Thank you for your contributions. If you decide that you need help, check out Wikipedia:Where to ask a question, ask me on my talk page, or place {{helpme}} on your talk page and someone will show up shortly to answer your questions. Please remember to sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. Below are some recommended guidelines to facilitate your involvement. Happy Editing! -- Piotr Konieczny aka Prokonsul Piotrus Talk 21:08, 27 May 2006 (UTC) Getting Started Wikipedia Tutorial How to edit a page The five pillars of Wikipedia Manual of Style Be bold in editing How to write a great article WikiProjects Getting your info out there Cite your sources Neutral Point of View Point of View Verifiability Uploading images Image use policy Getting more Wikipedia rules Policy Library Getting Help New contributors' help page Where to ask a question Help Desk Frequently Asked Questions Getting along Wikiquette Civility Sign your posts Wikipedians Conflict resolution Getting technical Pages needing attention Peer review Utilities Village pump

[edit] Puncturing EAS tags???

Hello. You once supplemented the sentence that since then reads "Deactivation is achieved by (...) submitting the tag to a strong electromagnetic field at the resonant frequency which will induce voltages exceeding the capacitor's breakdown voltage, which is artificially reduced by puncturing the tags". What does that addition mean? In shops, I never saw any commercial deactivator that requires anything more than swiping the tag over it. --saimhe (talk) 21:39, 31 January 2008 (UTC)

Puncturing is done at the factory for disposable RF tags, not in the shop! --Congruence (talk) 21:58, 31 January 2008 (UTC)

Still, I can't imagine what exactly is done and why it works. --saimhe (talk) 00:25, 1 February 2008 (UTC)

I imagine it locally reduces the distance between the two plates of the capacitor, lowering the dielectric breakdown voltage at those points, without significantly raising the overall capacity; when subjected to a resonating RF field of sufficient amplitude, breakdown at the puncture sites occurs, creating shorts and detuning the tag. Without this treatment, you would need to have an overall lower breakdown voltage, which would require a thinner film, but that would raise the capacitance and lower the resonant frequency unless you change the dimensions; but then you have constraints on the inductor and the Q value of the overall circuit; in other words the solution space for viable tags is small and puncturing probably allows to enlarge it. --Congruence (talk) 10:13, 1 February 2008 (UTC)

Thanks, it has sense now. Did you find that information (about tags being punctured) somewhere? Strange that I didn't hear anything similar despite my electronics background. Besides, that part of the article is too confusing without sources, or at least given the current wording. --saimhe (talk) 02:02, 2 February 2008 (UTC)