Patents by Inventor John J. Jurschak

John J. Jurschak 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).

  • Circuit for detecting loss of telephone line voltage
    Patent number: 3959605
    Abstract: The present invention deals with a new and useful circuit for monitoring the condition of a telephone line used for ordinary telephony. The circuit detects malfunctions such as severance and shorting which result in the termination of line potential. The invention does not require a floating (ungrounded) DC power supply and the output is referenced to earth-ground.
    Type: Grant
    Filed: September 11, 1974
    Date of Patent: May 25, 1976
    Inventor: John J. Jurschak