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.