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:
Feb. 21, 1984
Filed:
May. 11, 1981
Applicant:
Inventor:
Henry J Lukes, Bellevue, WA (US);
Assignee:
Sundstrand Data Control, Inc., Rockford, IL (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F / ;
U.S. Cl.
CPC ...
330109 ; 330304 ;
Abstract
Gain peaking and attenuation of audio signals above the peak gain frequency are provided in an audio frequency equalization preamplifier that includes an operational amplifier having a feedback network including first and second resistors and a feedback capacitor connected between the output and the second feedback resistor. Two or three low pass RC filter sections are connected between the audio signal source and the noninverting input of the operational amplifier with a circuit connecting a capacitor of the second RC section from the noninverting input to a node between the second feedback resistor and the feedback capacitor.