Patents Represented by Attorney Hugh Linton Logan

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  • Circuits having substantially parabolic output versus linear input characteristics
    Patent number: 4190896
    Abstract: Circuits are disclosed which have substantially parabolic output vs. linear input voltage relationships where the parabolic relationship starts anew each time a change in the input voltage reverses direction. Such circuits connected in the output paths of potentiometers make the overall combinations appear as potentiometers having extremely high resolutions.
    Type: Grant
    Filed: September 5, 1978
    Date of Patent: February 26, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Kenneth C. Knowlton
  • Phase shifting circuit
    Patent number: 4087737
    Abstract: A phase shifting circuit of the type comprising an operational amplifier with a capacitor in its negative feedback path and a resistor in series with its inverting input port is modified to provide adjustable phase shift. Adjustability is achieved by connecting a second capacitor in shunt with the resistor and, furthermore, a series-connected third capacitor and signal-inverting, controllable-gain amplifier also in shunt with the resistor.
    Type: Grant
    Filed: April 18, 1977
    Date of Patent: May 2, 1978
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Cosmo Henry De Gennaro