Patents by Inventor Richard G. V. Doble

Richard G. V. Doble 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).

  • High frequency signal measurement circuits utilizing temperature-sensitive devices
    Patent number: 5189362
    Abstract: A circuit for measuring the R.M.S. voltage of a high frequency signal (e.g. 100MHz) comprises two series-connected ntc thermistors (TH1, TH2) in a bridge circuit which is energized by a current source (1). The unknown signal is applied across one (TH1) of the thermistors and the resulting change in the resistance causes a D.C. output voltage to appear across the balanced terminals (T3, T4) of the bridge. This output voltage is proportional to the square of the R.M.S. voltage of the A.C. signal. In another embodiment, two ptc thermistors are connected in parallel in a bridge circuit which is energized by a voltage source, and are used to measure R.M.S. current. In each case, the thermistors are preferably operated in a negative slope resistance portion of their voltage-current characteristic.
    Type: Grant
    Filed: January 3, 1991
    Date of Patent: February 23, 1993
    Inventor: Richard G. V. Doble