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:
Sep. 08, 1987
Filed:
Dec. 23, 1985
Richard Erski, Fort Wayne, IN (US);
NAP Consumer Electronics Corp., New York, NY (US);
Abstract
Trigger signals both at horizontal and vertical line frequency required for an oscilloscope are derived from the horizontal synchronization output stage of a television receiver without any direct electrical connection to the receiver. A pick-up coil or tuned pick-up circuit is positioned in the vicinity of the receiver. The signals induced in the coil or circuit are applied to a comparator. The output of the comparator is at the required TTL level to provide the horizontal trigger to the oscilloscope. If a vertical trigger is also required, the comparator output is applied to a frequency doubler circuit. The output of the frequency doubler circuit is divided by 525, the so-divided output constituting vertical trigger circuits for the oscilloscope. A monitoring circuit for horizontal sync signals is connected to the comparator output and indicates the presence of horizontal sync signals by activation of a light emitting diode.