Abstract: A portable card reader designed to be carried in a wallet or purse has an electromagnetic head that reads information from a magnetic strip of a card or information is read from the card by an array of Hall sensors. In a further embodiment, the card reader uses a magnetic sensor based on magnetoresistive sensing of magnetic transitions of a magnetic stripe, suitable for use with small, portable electronic devices. In each embodiment, the information read from the card may be converted to a sequence of electronic bursts of predetermined frequency, preferably in the audible or ultrasound range. The sound signals are output by a speaker to the microphone of a telephone. The signal is then transmitted over the telephone lines to a remote receiver. The receiver then converts the sound bursts into signal pulses, which can be read using the computer software of a conventional card reader.

Abstract: A portable card reader is designed to be carried in a wallet or purse. In a first embodiment, the card reader has an electromagnetic head that reads information from a magnetic strip of a card. In a second embodiment, information is read from the card by an array of Hall sensors. In a further embodiment, the card reader uses a magnetic sensor based on magnetoresistive sensing of magnetic transitions of a magnetic stripe, suitable for use with small, portable electronic devices. In each embodiment, the information read from the card may be converted to a sequence of electronic bursts of predetermined frequency, preferably in the audible or ultrasound range. The sound signals are output by a speaker to the microphone of a telephone. The signal is then transmitted over the telephone lines to a remote receiver. The receiver then converts the sound bursts into signal pulses which can be read using the computer software of a conventional card reader.

Abstract: An authorization card, such as a credit card, has a security feature. The authorization card generally has two operational states, a disabled state and an enable state. In the disabled state, which is the default mode of operation, access to confidential information stored on the card is denied. The card remains in the disabled state until a PIN code is entered on a keypad provided on the card. Once the card is enabled, access to the confidential information is permitted for a predetermined period of time, after which the card reverts back to the default disabled state. The security feature is implemented on a magnetic card, an electronic smart card, and passive electronic card.