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:
May. 31, 1988
Filed:
Dec. 11, 1984
Michael E Long, Western Springs, IL (US);
Zenith Electronics Corporation, Glenview, IL (US);
Abstract
A cable converter for a television signal transmission having a stereo audio signal includes a coaxial output jack supplied with a 4.5 MHz aural intercarrier and a DC voltage for volume control and mute purposes. An interface circuit includes a pair of transistors connected in series for controlling the DC voltage level on the output jack as a function of desired volume level. One of the two transistors functions as a switch that may be operated from the cable head-end to provide a mute voltage level at the output jack for disabling the audio for nonauthorized channels. Optionally, a head-end control signal may operate another transistor for preventing coupling of the 4.5 Mhz aural intercarrier to the output jack.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile