a decoder for a pay television system incorporates a receiver for receiving scrambled programming and control data transmitted from a remote location , with the control data including data corresponding to the program fee and the program status , and a manual switch for selectively descrambling the program data when the program status is a pay - per - view program . the decoder has a storage unit for storing a credit value , transmitted from the remote location , and the decoder has timer apparatus for measuring the time during which a pay - per - view program is being received and for subtracting a program fee periodically from the value stored in the storage unit , during the time of reception of the selected program , provided the switch is operated to descramble the program .