This is a modification of samyk's magspoof (https://github.com/samyk/magspoof) which cleans up the code a tad, and slightly changes the way that the data is sent.
Essentially, this version of magspoof will try different combinations of emulated forward/reverse swipes (with the different tracks) to try to increase compatibility for the maximum number of card readers.
Simply keep pressing the button to keep sending the track data in different combinations of forward/reverse swiping.