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:
Aug. 23, 1988
Filed:
Jun. 02, 1987
Timothy J Donovan, Wheeling, IL (US);
Daniel L Reneau, Elmhurst, IL (US);
Zenith Electronics Corporation, Glenview, IL (US);
Abstract
An automatic color tuning system includes a counter controlled oscillator that is started in the middle of its controllable frequency range. If the counter counts around and no color burst signal is detected, the oscillator is stopped. Whenever the oscillator is sweeping, an automatic phase control circuit is operated at low gain for assuring that the oscillator will be close to the frequency of the color burst signal when lock-up occurs. Whenever the oscillator is stopped, the automatic phase control circuit gain is made high. Once the automatic phase control circuit locks up the oscillator to a color burst signal, a subsequent loss of the color signal does not re-initiate the counter.