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:
Jul. 15, 1980
Filed:
Sep. 01, 1978
Jon K Clemens, Skillman, NJ (US);
RCA Corporation, New York, NY (US);
Abstract
In a video disc playback apparatus, an active tracking control system is provided using a single pilot signal. The pilot signal is recorded on an information track of a video disc record such that each convolution of the track contains a non-integral number of cycles of the pilot signal. The phase of the pilot signal in a given convolution bears a known relationship to the phase of the pilot signals in the convolutions preceding and succeeding the given convolution. The given convolution includes information representing a reference phase signal. The phase of the recovered reference signal is compared to the phase of the recovered pilot signal which may include phase information from adjacent convolutions to provide an error signal. Pickup positioning apparatus is made responsive to the error signal for maintaining the pickup on the desired path along the information track.