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:
May. 19, 1998
Filed:
Oct. 11, 1995
Joseph F Bader, Crete, IL (US);
Robert W Wardzala, Downers Grove, IL (US);
Federal Signal Corporation, University Park, IL (US);
Abstract
A tone generating circuit for delivering power to a speaker modulated fourth harmonic audio square wave signal by its fundamental to produce a modulated audio signal within a selected frequency range. The tone generating circuit may be incorporated in a power delivering circuit that supplies a pulse width modulated audio signal to a speaker in one mode of operation, a fourth harmonic modulated audio signal in a second mode of operation, and a square wave audio signal in a third mode of operation.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile