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. 14, 1986
Filed:
Jun. 15, 1984
Gordon L Richard, Minco, OK (US);
Baptist Medical Center of Oklahoma, Inc., Oklahoma City, OK (US);
Abstract
An apparatus and a method modulate a carrier signal so that the resultant modulated signal varies between a value substantially equal to the quiescent level of the carrier signal and peak values up to several hundred percent of the quiescent level of the carrier signal. The apparatus includes an electrical circuit for adjusting the modulating signal so that it is clamped at a reference value to prevent overmodulation. The clamped signal controls a variable resistance mechanism which forms a part of the gain determining portion of a modulator circuit including an amplifier. The amplifier modulates the carrier signal in accordance with the gain determined by the variable resistance. The variable resistance is controlled by the clamped signal so that it causes the gain of the amplifier circuit to vary between approximately one and a value greater than one. So that the apparatus can be used by a person having a hearing impediment wherein the dynamic range detectable by the user is less than the dynamic range detectable by a normal ear, the apparatus also includes a circuit which compresses a detected acoustical signal which is within a first dynamic range into an electrical modulating signal within a dynamic range which is smaller than the first dynamic range and which is within the dynamic range perceivable by the user of the apparatus.