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:
Jan. 20, 1981
Filed:
Sep. 07, 1979
Takashi Sugimoto, Yokohama, JP;
Hiroshi Takahashi, Ayase, JP;
Abstract
Abnormal separation detecting circuit of chromatic signals transmitted by a SECAM system comprises a detection circuit which receives a chromatic signal made up of R-Y signals and B-Y signals respectively added with identification signals I.sub.1 and I.sub.2 at their front ends for detecting the identification signals I.sub.1 and I.sub.2 to produce currents corresponding to their frequencies, a differential amplifier comprising a pair of transistors ON OFF controlled by pulse signal of opposite signals which vary their phases in synchronism with the initiation of the periods of the R-Y signals and the B-Y signals of the chromatic signal and respectively applied to the base electrodes of the transistors, a current mirror circuit controlled its operation by the differential amplifier circuit, and a capacitor connected across the juncture of the current output terminal of the current mirror circuit and the current input terminal of the differential amplifier, and a reference potential point to be charged and discharged in accordance with the operation of the differential amplifier.