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:
Jun. 27, 1978
Filed:
Dec. 06, 1976
John Pang Yu, Indianapolis, IN (US);
RCA Corporation, New York, NY (US);
Abstract
Video record player has RF output terminal linked to antenna terminals of a television receiver, and an RF input terminal coupled to antenna lead-in. Player's processing circuits provide respective sound signal and composite video signal outputs during record playback. First oscillator, operating at intercarrier sound frequency (e.g., 4.5 MHz), is subject to frequency modulation by player's sound signal output (when present). Sum of oscillator output and player's composite video signal output (when present) forms modulating signal for an amplitude modulator, which receives carrier waves from second oscillator, operating at selected broadcast picture carrier frequency. A first diode is coupled between modulator output terminal and player's RF output terminal, while second diode is coupled between player's RF input terminal and reference potential point. Normally closed relay provides a conductive path between player's RF input and output terminals when closed. Forward biasing voltages for diodes, and energizing potential for relay's control winding (as well as operating potentials for oscillators) are provided by player's power supply when player is switched on, so that carrier waves from player are supplied to receiver while antenna lead-in is isolated. When player is switched off, antenna lead-in is automatically linked to receiver's antenna terminals.