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. 30, 1977
Filed:
Apr. 12, 1976
David H Meehan, Chicago, IL (US);
George J Tzakis, Chicago, IL (US);
Zenith Radio Corporation, Glenview, IL (US);
Abstract
A television receiver includes a conventional tri-color cathode ray tube display system having horizontal and vertical scansion systems. Conventional signal receiving and processing circuitry recovers picture, sound and scansion synchronizing information. A high voltage shutdown circuit is responsive to excesses of either high voltage or CRT beam current. The former being detected by a resistance divider coupled between high voltage and ground while the latter is sensed by a resistor placed in series with the secondary winding of the horizontal deflection transformer. A PNP, NPN transistor pair configured to form a switch analogous to a silicon controlled rectifier responds to detected excesses of beam current or high voltage and loads down the operating supply to the horizontal scansion oscillator to terminate high voltage generation. The transistor pair accommodates a degenerating network to reject false triggering.