Patents by Inventor Everett A. Gilbert

Everett A. Gilbert has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Frequency shift demodulator
    Patent number: 5015961
    Abstract: The invention improves the ability of the FS demodulator-circuit of an FS digital transmission system so as to withstand noise with low error count. The invention uses two different types of all pass networks and a phase measuring circuit to average random noise and enhance the desired FS frequencies.
    Type: Grant
    Filed: August 3, 1990
    Date of Patent: May 14, 1991
    Assignee: Da-Tel Research Company, Incorporated
    Inventors: Robert E. Springer, George F. Hafer, Everett A. Gilbert
  • Audio frequency interface for differential relays
    Patent number: 4878241
    Abstract: The invention interfaces a two-wire 60 Hz circuit to two circuits, each unidirectional, sending and receiving, and carrying frequency modulated audio tones containing the amplitude and phase of the 60 Hz voltage impressed on the 60 Hz circuit. The invention is used to interface differential relays used by electric utilities to detect power transmission line faults to a four-wire voice band communication line.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: October 31, 1989
    Assignee: Da-Tel Research Company, Incorporated
    Inventor: Everett A. Gilbert