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:
Oct. 13, 1981
Filed:
Feb. 19, 1980
Yasuaki Watanabe, Kasukabe, JP;
Teruaki Noda, Noda, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
A television signal discrimination system is used in a television receiver provided with an electronic tuner for producing as output an intermediate-frequency signal whose synchronizing frequency is varied in response to an applied voltage and with a circuit for detecting the output signal of the electronic tuner. This system comprises a first synchronizing signal separation circuit supplied with the output of the detection circuit and separating a vertical synchronizing signal, a first integration circuit connected to the output side of the first synchronizing signal separation circuit, a circuit supplied with an output voltage of the first integration circuit and a reference voltage and operating to compare the magnitudes thereof, a second synchronizing signal separation circuit supplied with the output of the detection circuit and separating a vertical synchronizing signal, a second integration circuit connected to the output side of the second synchronizing signal separation circuit, a circuit for discriminating the frequency of the output of the electronic tuner, and a circuit for discriminating a normal television signal on the basis of the output of the voltage comparing circuit, the output of the second integration circuit, and the output of the frequency discriminating circuit. The first synchronizing signal separation circuit and the first integration circuit producing, as output, different voltages, with the reference voltage as a borderline, depending on and distinguishing between the case where the output signal of the detection circuit is a normal television signal and the case where the output signal is a different spurious television signal.