System for transmitting a commercial program in a CATV system

Claim 1

In a system for transmitting television signals in a CATV system wherein a television signal of a priority channel is selectively scrambled with an encoding at a broadcasting station to produce in the priority channel 1) a scrambled television signal for terminal devices of subscribers and 2) non-scrambled television signal for non-subscribers used for transmitting a commercial program, the scrambled and non-scrambled television signals are alternately transmitted from the broadcasting station to a local center in the priority channel, and the scrambled television signal is descrambled at the local center, the descrambled television signal is re-scrambled by an encoder with another encoding at the local center, the re-scrambled television signal and the non-scrambled television signal are alternately transmitted to terminal devices wherein the system comprises: detector means, provided in the local center, for detecting said scrambled television signal and said non-scrambled television signal in the priority channel and said detector means for producing a scrambled signal and a non-scrambled signal in accordance with said detected signals; switching means, responsive to said scrambled signal, for feeding said descrambled television signal to said encoder for re-scrambling said television signal, and responsive to said non-scrambled signal for passing said non-scrambled television signal without passing through said encoder; and transmitting means for alternately transmitting said re-scrambled television signal and said non-scrambled television signal to subscriber and non-subscriber terminal devices.

Claim 7

A system for a local center to which 1) scrambled television signals through a plurality of priority channels of respective scrambling systems and 2) non-scrambled television signals through said plurality of priority channels are applied from broadcasting stations, wherein said scrambled television signal and the non-scrambled television signal of each priority channel are alternately transmitted, and the scrambled television signals are re-scrambled with a re-scrambling system at the local center, the system comprising: detector means for detecting each of the scrambled television signals and for producing a scramble signal when detected; descrambling means for descrambling the scrambled television signal; re-scrambling means for re-scrambling the descrambled television signals with a re-scrambling system; and transmitting means for transmitting the re-scrambled television signal to a plurality of terminal devices.

Claim 8

A system for a local center to which 1) scrambled television signals through a plurality of priority channels of respective scrambling systems and 2) non-scrambled television signals through said plurality of priority channels are applied from broadcasting stations, wherein said scrambled television signal and the non-scrambled television signal of each priority channel are alternately transmitted, and the scrambled television signals are re-scrambled with a re-scrambling system at the local center, the system comprising: detector means for detecting each of the scrambled television signals and for producing a scramble signal when detected; descrambling means for descrambling the scrambled television signal; re-scrambling means for re-scrambling the descrambled television signals with a re-scrambling system; and transmitting means for transmitting the re-scrambled television signal to a plurality of terminal devices.