Transponder wrist watch providing service tariff pre-payment function

摘要

The wrist watch (11) has a read/write memory (24) in which a pre-payment amount can be entered, with the memory updated by deleting the tariff for a utilised service each time the service is used, via an inductive coupling with an external transceiver. Each wrist watch has a transceiver (23) for switched operation between data input and data output modes via data exchange (27) with a different transponder wrist watch (11) allowing transfer of a stored tariff pre-payment.