×

Secured scramble decoder filter

  • US 4,097,894 A
  • Filed: 11/01/1976
  • Issued: 06/27/1978
  • Est. Priority Date: 11/01/1976
  • Status: Expired due to Term
First Claim
Patent Images

1. A circuit device for removing an interfering signal purposely injected between the video carrier and audio carrier of a television transmission signal, said interfering signal having a frequency substantially in the range of one-fourth to three-fourths of the frequency interval between the video carrier and the audio carrier comprising:

  • a housing;

    a narrow band notch filter mounted in said housing;

    means for tuning said filter to the optimum frequency for eliminating the interfering signal, the latter having a frequency substantially in the range of one-fourth to three-fourths of the frequency interval between the video carrier and the audio carrier; and

    means for mounting said housing, said mounting means including means for securing said filter against unauthorized removal from said mounting.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×