In other part of HOW TO BUID YOUR OWN ATM, I have found recently a tutorial for audio (DIEBOLD)with all necessary for decrypting magstrip in audio and all what you need to buy ...
This is a recent post (not by me) and is not finish (I will post news)
Just read :
What you need to make it:
1. Mini video recorder
Mini Video Audio Spy Camera - Chewing Gum Wrapper Sized - 48$
Mini Spy Digital Video Camera with Encryption Feature - 44.63$
or some other mini camera
2. Single-track reading head attached to the microphone input of the mini video recorder
the information of the reading heads will be added later
3. Extended battery if you want to record more than 1-2 hour (limited to the default battery of the mini spy digital camera)
4. Software (under development)
5. Mold (of course)
How to do it (will be updated later):
I will explain it simple:
1.You need to unsolder default microphone of mini spy camera and connect reading head with tho wires to the board.
2.Move default camera away from the board near the end of the mold (see the pictures)
Software used to decode such data.
Magstripper - can be found here (http://sourceforge.net/projects/magstripper/) - you can import your wav file and get the track2 data.
... can be found here http://mreader.free.fr/ (source code included)
f2f waveform example:
The howto will be updated soon!