Information transmission device using acoustic signal transmission path

摘要

The transmission device is used for information coded as a notched profile along one side edge of a credit card (1), or key, which is scanned to provide a corresponding acoustic signal which can be transmitted via an acoustic signal transmission path, e.g. a telephone link. Pref. the information is coded via the spacings between the notches of the edge profile, the acoustically transmitted information decoded at the reception end of the acoustic signal path, e.g. for controlling the information displayed on a monitor screen (36).