I got given a piece of electronics to take apart that has a magnetic swipe card reader built into it.
Upon taking it apart the card reader itself (which appears very much like a tape deck head) seems to have 5 pins, only three of which have wires attached in the current circuit (I'll call these 1 through 3 and will ignore the disconnected pins).
Pin 2 is obviously the ground, as it's connected to the outer case (this was also obvious from the circuit board it was attached to).
Resistance from pin 1 to pin 3 is about 65 ohms. 1-2 and 2-3 are OL.
I tried putting +5V (limited by a 1k ohm resistor) across 1 with 3 hooked up to my oscilloscope, but the voltage was a steady +5V with no change when I swiped a card.
Same results for +5V through 3 with 1 hooked up to the scope.
Oscilloscope does not show any voltage through ground (pin 2) when voltage is applied to 1 or 3.
So I'm sort of stuck.
I tried googling around, but so far I haven't really found much information on how the mag stripe readers actually work that gives me a better idea of how I might provoke a reaction from this thing.
Do any of you guys have any thoughts or suggestions?