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Credit card & magnet

  1. Jul 5, 2006 #1
    will i damage my credit card if i put it on top of a strong magnet?

    i have a few smart cards together with my credit cards in my wallet. when i use my smart card (like a security access card to open doors, gates with electronic access) i tap my wallet on the reading pad which i believe is rather strong magnet.

    will this (in long run) damage my other cards?
  2. jcsd
  3. Jul 5, 2006 #2


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    If the pad won't hold up a paper clip or some other small metal/iron object, then its not magnetic or at least not magnetic enough to matter.

    Chances are its RFID or some other rf technology.

    Also, If it hasn't wiped your credit cards by now chances are it won't.
  4. Jul 6, 2006 #3


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    Smart card readers are not magnetic. They use RF to induce a current in a loop of wire embedded in your card. The card, using this power, then broadcasts an electronic message via radio. The reader receives this message, verifies its authenticity, and then opens the door.

    - Warren
  5. Jul 6, 2006 #4


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    The situation you described may not do it, but a magnetic field can mess up a credit card or Hotel key type device.

    At a recent meeting, the group toured a generator facility. Everyone that entered the room had to have Hotel desk re-do their keys when they got back. No one could get into their room.
  6. Jul 6, 2006 #5


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    Be careful also of the counter-top units that disable security tags at a store checkout. They usually have a lable warning against getting your cards too close.
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