US Patent 7896248 Card reader device and method of use

A card reader device for reading a card having data stored on a magnetic stripe incorporated into the card is disclosed in which the card reader device comprises a read head for passing a magnetic stripe of a card by to read data stored on a magnetic stripe and for producing a signal indicative of data stored on a magnetic stripe, a signal setting device for setting an amplitude of the signal indicative of data stored on a magnetic stripe, and an output plug adapted to be inserted into a headset jack associated with a host device for providing the signal indicative of data stored on a magnetic stripe to a host device.