Output Coupling From Grid Patents (Class 330/162)
  • Patent number: 7053710
    Abstract: A vacuum tube amplifier is formed of a vacuum tube having a cathode, a plate, a grid, and a heater to radiate electrons from the cathode. An input signal is supplied to the plate, an output signal is obtained at the grid, and a predetermined low voltage is supplied to the heater. The voltage supplied to the heater can be low, thereby significantly decreasing an overall consumption of electric power for the vacuum tube amplifier.
    Type: Grant
    Filed: April 2, 2004
    Date of Patent: May 30, 2006
    Assignee: Korg, Inc.
    Inventor: Fumio Mieda
  • Publication number: 20040257158
    Abstract: A vacuum tube amplifier is formed of a vacuum tube having a cathode, a plate, a grid, and a heater to radiate electrons from the cathode. An input signal is supplied to the plate, an output signal is obtained at the grid, and a predetermined low voltage is supplied to the heater. The voltage supplied to the heater can be low, thereby significantly decreasing an overall consumption of electric power for the vacuum tube amplifier.
    Type: Application
    Filed: April 2, 2004
    Publication date: December 23, 2004
    Inventor: Fumio Mieda
  • Patent number: 4276513
    Abstract: An operational amplifier (33) is continuously switched back-and-forth between an auto-zero mode of operation and an accurate amplification mode of operation. During the auto-zero mode of operation, the junction between an offset voltage compensation (e.g., auto-zero) capacitor (35) and the noninverting input of the operational amplifier (33) is referenced to the input signal voltage via a bootstrap amplifier (31), rather than being tied to ground. Further, during the auto-zero mode of operation, the other end of the auto-zero capacitor (35) is referenced to the output of the operational amplifier (33), which is also connected to the inverting input of the operational amplifier. As a result, the auto-zero capacitor (35) is charged to a voltage level equal to the input offset voltage of the operational amplifier, but in polarity opposition thereto.
    Type: Grant
    Filed: September 14, 1979
    Date of Patent: June 30, 1981
    Assignee: John Fluke Mfg. Co., Inc.
    Inventors: Craig E. Johnston, Ramesh C. Goyal