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:
Dec. 09, 1986

Filed:

Mar. 22, 1984
Applicant:
Inventors:

Takashi Okada, Yokohama, JP;

Takao Mogi, Tokyo, JP;

Assignee:

Sony Corporation, Tokyo, JP;

Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04N / ; G11B / ;
U.S. Cl.
CPC ...
358122 ; 358121 ; 358123 ; 358124 ; 360 27 ;
Abstract

A scrambled television program that is received and recorded in a scrambled fashion includes program code and corresponding key codes for use in descrambling the recorded scrambled signal. The program codes and key codes are retained in a memory so that upon reproduction the key code can be read out of the memory and fed to a descramble pattern generator for descrambling the reproduced scrambled signal. By placing the program code and key code at the end of the scrambled program the scrambled signal cannot be descrambled until the entire program has been first received. By dividing the memory into permanent and temporary memories and adding an identification code to the transmitted scrambled signal, which selects either the permanent or temporary memory, and counting the number of times that the temporary memory is read out there can be a limitation placed on the number of times that the scrambled program is reproduced and decoded for viewing. Once a selected number is reached the contents of the temporary memory are erased, thereby preventing descrambling of the reproduced signal.


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