A multi-video/audio system and a method of controlling the same. The system comprises a CPU for controlling the entire operation of the system, a card input/output unit for ascertaining a card identification number, a card private number and deposit balance of the user and issuing a service receipt for...http://www.google.de/patents/US5499048?utm_source=gb-gplus-sharePatent US5499048 - Multi-video/audio system and method of controlling the same
