| abstract |
A subscription television receiver for receiving a scrambled television signal includes a card or ticket reader into which a ticket having a unique coding pattern is placed. The card reader comprises a circuit for developing a card identification signal corresponding to the ticket code pattern. That signal is compared with a program identification signal that is periodically transmitted to the receiver along with the scrambled television signal. When a predetermined correlation between the card and program identification signals is detected, an enabling signal is produced to unscramble the received television signal and thereby permit the received program to be viewed in unscrambled form. In another aspect of the invention, the card contains additional coding which is sensed in the card reader to produce a channel select signal to enable the receiver to receive one of a plurality of programs. In yet another aspect of the invention, a card identification signal is transmitted along with other signals to enable the subscriber to retransmit data that can be used for polling or billing purposes. |