Patents by Inventor Roger E. Holtz

Roger E. Holtz 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).

  • Battery feed circuit for a telephone system
    Patent number: 4813066
    Abstract: An arrangement is disclosed for delivering DC power (battery), voice, and ta signals from a telephone controller to a telephone station over first and second wire-pairs. Minimum interference between these signals is achieved when the first wire-pair is used as the voice signal path and the second wire-pair is used as the data signal path. DC power is fed out of the controller and into the center tap of an audio transformer interconnected with the first wire-pair. Ground current is returned to the controller through a balanced resistive circuit interconnected with the second wire-pair.
    Type: Grant
    Filed: July 13, 1987
    Date of Patent: March 14, 1989
    Assignee: American Telephone and Telegraph Company, AT&T Information Systems
    Inventors: Roger E. Holtz, Thomas A. Stahl
  • Telephone ringing extender
    Patent number: 4144408
    Abstract: A telephone ringing extender is shown which includes a ringing signal detector and a switch. In response to ringing signals, the ringing extender grounds the tip conductor to operate telephone ringers bridged on the loop. Protection against excessive voltages and excessive currents is also provided.
    Type: Grant
    Filed: January 30, 1978
    Date of Patent: March 13, 1979
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Roger E. Holtz, Bernard A. Tilson, Gordon D. Woods