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my laundry room in college used the same technology. sucks if you damage the card (by sitting on your wallet, for example).



Of maybe like electronic lunch chits. Once they go through the reader, it might 'burn the circuit' being equivalent to stamping a hole into the card.


Back in the days when public phone booths were still a thing, the local telecom introduced pre-paid chip cards that you used for paying for your call. They were widely advertised as “fraud proof” because the chip physically burned polyfuses on the silicon as credits were used up. You can never restore a card that ran out of credits that way, they said.

It was simple to make a card insert and a circuit that just lied to the phone that a fuse was burned. They switched to a different system soon after.




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