| 摘要 |
PURPOSE:To substantially prevent an illegal viewing with the CATV system by providing a counter that comprises three counters to the terminal side to avoid the clearing of chargeable information if any illegality occurs. CONSTITUTION:The TV signal transmitted through the CATV line from the central station is inputted to a TV set 13 via a terminal equipment 12. The counter 14 of the equipment 12 is composed of three counters. The primary counter counts the times of selecting of the chargeable-viewing channels between the telephone protocol start request commands. The secondary counter counts the accumulating number, and the tertiary counts the times of reception. The terminal equipment 12 transmits through the telephone line the chargeable viewing information as well as the counter information to the central station by a request command. The central station transmits through the CATV line a confirmation signal and a feedback of the information from the primary and the secondary counters. The equipment 12 collates this feedback information with the information is the counter 14, and only when they coincide with each other, the equipment 12 clears the chargeable viewing information and the primary counter. |
