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.

Date of Patent:
Feb. 05, 1991

Filed:

Sep. 30, 1988
Applicant:
Inventor:

Pierre Blais, Montreal, CA;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
380-7 ; 358 86 ; 455-1 ;
Abstract

In order to selectively jam M selected channels to selected subscribers in a CATV system, each of M different oscillating signals, each of which oscillating signals has a duration longer than the duration of the horizontal synchronization signal of the television channel it is to jam and a frequency higher than the carrier wave of the channel it is to jam, are in turn added to the television signal circuits of those subscribers who are not authorized to receive the particular channel being jammed by the jamming signal being added. The television set of the non-authorized subscriber picks up the higher frequency jamming signal as the valid horizontal synchronization signal and therefore ignores the valid horizontal synchronization signal, with the result that the channel in question is unviewable on the television set of the non-authorized subscriber.


Find Patent Forward Citations

Blais, Pierre. (1991). Method and apparatus for jamming selected television programs (U.S. Patent No. 4991206). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4991206

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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