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:
Nov. 04, 1980
Filed:
May. 12, 1978
Applicant:
Inventor:
Anthony J Ley, Bievres, FR;
Assignee:
ENERTEC, Montrouge, FR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R / ; H03K / ; H04Q / ;
U.S. Cl.
CPC ...
3401 / ; 324 / ; 328134 ; 3403 / ;
Abstract
A remotely-controllable relay which is controlled by 175 Hz ripple voltage superimposed on the mains supply voltage in an electric-power distribution network contains an oscillator generating a signal at 173 Hz. This is mixed with the network voltage so that, when ripple voltage is present, a beat note at a frequency of 2 to 3 Hz is generated. This beat note is separated from the unwanted signals, such as the mains supply voltage, by a third order active low-pass filter to control operation of the relay. A similar technique provides simplified detection of output signals from correlation-type filters.