Magnetic Swipe Cards are used everywhere, probably the most common one that we all have in our wallets is the one that is built into our bank and credit cards. Craig from the Flashing LEDs blog was had a reader that was sitting around with no purpose. He swiped his University ID through it and found that the only thing on track 2 was university ID number, this card system is used for lots of systems around the university. He built a system that was able to simulate the card being swiped. Turns out there might be more to the card than what is living on track 2 since it was not able to fool the card system but I am betting if all of the tracks were analyzed the security that the card provides might come crashing down.
Should be as small as practical so I feel more like an awesome spy. Lots of surface mount components, and a professionally made PCB (from batchPCB.com)
Needs a powerful, compact battery to run the coil. Also needs to be something I have hanging around. I went for a 9V, and designed the PCB to have the same outline as a 9V battery so it could sit on top of it.
Should be able to store card sequences in memory and let me select which sequence to generate
Should be able to interface to a card reader so I can record a new card just by swiping it instead of needing a computer
However if I do have a computer handy, I should be able to use it as an RS232 adapter for the card reader and display decoded info on a terminal.”