Building a RFID reader
RFID cards are commonly used for access control and bus/train tickets. They are convenient because no direct contact is required to transfer information to and from the card. The card itself is powered by the RFID reader, so there is no battery to change.The most common design for RFID reader is to use a series resonate circuit. This consists of a single inductor and a capacitor excited by a low impedance voltage source.
   Building a RFID reader
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