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. 25, 1976
Filed:
Jan. 15, 1975
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., , JA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03B / ; H04B / ;
U.S. Cl.
CPC ...
325422 ; 178 / ; 331 / ; 334 16 ;
Abstract
A local oscillation circuit for a tuner having a reduced inter-channel deviation in AFC sensitivity. The local oscillation circuit comprises a resonance circuit capable of varying a tuning frequency by means of a variable capacitive element additionally provided with a variable capacitive diode which is applied with a control voltage in dependence upon variation in the frequency detected from the output signal of the tuner, thereby to effect an automatic frequency control. A single variable capacitive diode is coupled to the variable capacitive element of the resonance circuit in a parallel and a series connections.