Patents by Inventor Charles G. Leedham

Charles G. Leedham 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).

  • Receiver for A.C. electrical supply signalling arrangement
    Patent number: 4392121
    Abstract: A receiver for an a.c. electrical supply signalling arrangement of the kind in which information is transmitted by impressing on the supply voltage waveform voltage reductions which bridge the zero crossings in the waveform wherein detection by the receiver of an impressed voltage reduction is achieved by comparing the integral of the supply voltage over a period immediately preceding a voltage zero crossing when a voltage reduction is present with a corresponding integral obtained when no voltage reduction is present.
    Type: Grant
    Filed: December 2, 1980
    Date of Patent: July 5, 1983
    Assignee: The General Electric Company Limited
    Inventors: Frederick M. Gray, Charles G. Leedham