Patents by Inventor Norman Thorogood Thurlow

Norman Thorogood Thurlow 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).

  • Telecommunications transmission and signalling circuits
    Patent number: 4079208
    Abstract: A d.c. signal detector circuit for a telephone exchange which comprises a level detector which is so connected that it can sense current flowing in a telephone line. The level detector is arranged to switch states when a loop is established in a telephone circuit. Two level detectors can be employed to sense the establishment of a loop, a coin pulse, or an earth loop.
    Type: Grant
    Filed: November 23, 1976
    Date of Patent: March 14, 1978
    Assignee: The Post Office
    Inventors: Alastair Stanley Rogers, Norman Thorogood Thurlow