The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 12, 1982
Filed:
Jun. 11, 1980
Etablissement Public de Diffusion Dit: Telediffusion de France, Montrouge, FR;
Other;
Abstract
A television system with access control comprises a transmitter and receis. The transmitter comprises a video signal and sound signal formation circuit, means for transmitting these signals and a jamming circuit using a service key. Each receiver comprises means for receiving the transmitted signals, means for the display of the picture and for restoring the sound and an unjamming circuit connected to the reception means and working with the service key. It also comprises a subscription management center and in the transmitter a digital signal generator, a circuit for the formation of digital messages and a data broadcasting system and in the receiver a subscription card, an extraction circuit for the data, and a circuit for restoring the service key. There is also at least one subscription card loading station connected to the subscription management center.