Patents by Inventor Robert Fredres

Robert Fredres 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).

  • CRT Degaussing system
    Patent number: 4445072
    Abstract: A degaussing system in a CRT device detects a trigger pulse and provides a timed control pulse which controls a power circuit "on" time. The power supplied to the degaussing coil is gradually reduced by the increasing resistance of a PTC thermistor in series with the degaussing coil, then turned off by the end of the control pulse. Degaussing can be initiated manually or automatically as often as desired, and may be triggered automatically in response to a predetermined period of device inactivity.
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: April 24, 1984
    Assignee: Motorola, Inc.
    Inventor: Robert Fredres