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:
Mar. 02, 1982
Filed:
Aug. 27, 1979
Francis W Hopwood, Severna Park, MD (US);
John P Muhlbaier, Joppa, MD (US);
Jeffrey T Oakes, Morrisville, NC (US);
James T Haynes, Elicott City, MD (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A system for comparing the frequency of a voltage controlled oscillator to a stable reference oscillator to generate control signals which maintain the voltage controlled oscillator in phase lock with the reference oscillator. The circuit utilizes a digital frequency comparator to determine whether the output frequency of the voltage controlled oscillator is above or below the reference frequency. When the frequency of the oscillator is either above or below the desired value, pulses are generated which are integrated to produce a DC signal which changes the frequency of the oscillator to achieve the desired value. Additionally, a continuous electrical signal is generated when the output of the voltage controlled oscillator is in phase with the reference signal. When phase lock is achieved the output of the frequency determining circuit goes to zero and phase lock is maintained by the continuous electrical signal.