AVLAESARE FOER IDENTIFIERINGSBRICKA

摘要

A token reader has a first array of flat spiral transmitter coils (8) mounted on a printed circuit board (6) and a second array of corresponding flat spiral receiver coils (11) mounted on a printed circuit board (7). Selective inhibition of the electromagnetic coupling between the transmitter and receiver coils is effected by conductive inserts (13) carried on an insulating card token (4) which is inserted between the two coil arrays, to provide a coded output from the receiver coils (11), for amplification and comparison in an electronic security checking system (18-21).