Abstract: The credit card information management system checks the creditability of a credit card intended to be used for purchase of goods or service by using the card information owned by member stores of credit companies. A host computer of the card management center outputs information regarding the validity or invalidity of a credit card of a customer member of a credit company as card information, a transmission facility wirelessly transmits digital data of the card information. A receiving facility of a member store receives radio signals of the card information and checks whether or not there is any missing of data. If any missing occurs, a transfer of the missed data is requested to the host computer.

Abstract: A system for managing sales of goods for vending machines includes a goods control center, a plurality of vending machines, and terminal computers equipped in the respective vending machines. The goods control center includes a host computer for preparing digital data signals as control instructions, and a frequency moderation sub-carrier broadcasting facility as a transmission facility for outputting the digital data signals. Each vending machine has a receiving facility for receiving the digital data signals from the goods control center, and a responding facility. Each terminal computer receives the digital data signals and selectively extracts the digital data as the control instructions necessary for the vending machine to thereby store the digital data necessary for the vending machine in a memory.