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:
Mar. 20, 1984
Filed:
Feb. 19, 1982
Yasushi Katsumata, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
In an active equalizer for selectively boosting or attenuating predetermined frequencies of audio or other electrical signals, and which comprises an inverting amplifier having an inverting input which receives the input signal through an input resistance and an output connected with the inverting input through a feedback resistance and at which the equalized output is derived, and an active filter for determining the frequencies to be boosted or attenuated; there is further provided a change-over switch having a boosting position in which the input signal is applied to the active filter, an attenuating position in which the output of the inverting filter is applied to the active filter and a neutral position, and a potentiometer connected between the output of the active filter and the inverting input of the inverting amplifier and being operable in concert with the change-over switch for determining the extent to which the frequencies determined by the active filter are boosted or attenuated.