Hello again,
I read this topic → Quirks of the T5577 & cloning tags to the xEM.
Could be a problem in antenna design ?
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In short, it was not the cloner’s code or what it was doing that was the problem … the problem was that the antenna coil inside the cloner was designed to work with cards and keyfobs, not small cylindrical tags like the xEM. The cloner was not magnetically coupling well with the xEM, and because passive RFID systems use this magnetic field to send both power and data over the coupling, there was a significant chance that the T5577 chips inside these xEMs were being corrupted.
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