Patents Examined by Daniel Seller
  • Tone generation
    Patent number: 9900705
    Abstract: A tone generation system includes a square wave signal generator configured to generate a first series of square wave signals to replicate a fundamental frequency of a desired mechanical tone, and a second series of square waves signals to replicate a second harmonic of the desired mechanical tone. An amplifier is configured to receive the first and second series of square waves, and a speaker is connected to receive an output signal from the amplifier.
    Type: Grant
    Filed: January 23, 2014
    Date of Patent: February 20, 2018
    Assignee: Federal Signal Corporation
    Inventors: Scott Cassidy, Lonnie Moravetz, David L. Corey, Robert Steiert