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. 12, 1979
Filed:
Feb. 02, 1978
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An automatic local oscillation frequency control apparatus for a television receiver is disclosed, wherein a video intermediate frequency (VIF) signal is applied to an FM discriminator for generating an AFC voltage through a phase shifter comprised of a serial-parallel resonance circuit, and one of the serial resonance frequency and the parallel resonance frequency of the serial-parallel resonance circuit is selected to be a frequency near a picture carrier frequency while the other is selected to be a frequency which is made by subtracting one half of a differential frequency between the picture carrier frequency and a sound carrier frequency from the picture carrier frequency. The present apparatus can attain an automatic frequency control having a wide pull-in range and a wide hold range.