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| Number | Title | Issue Date |
| 7053710 | Vacuum tube amplifier having grid as output and plate as input 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 ... | 05/30/2006 |
| 5880632 | Tube amplifier having special configuration with two or more tubes There is provided a tube amplifier comprising a first vacuum tube K3 having a plate applied with a positive voltage and a cathode applied with a negative voltage by a first resistor, a second vacuum tube K4 having a grid connected to the cathode of the fi... | 03/09/1999 |
| 5680074 | Tube amplifier having specific configuration with four tubes There is provided a tube amplifier comprising a first vacuum tube K3 having a plate applied with a positive voltage and a cathode applied with a negative voltage by a first resistor, a second vacuum tube K4 having a grid connected to the cathode of the fi... | 10/21/1997 |
| 5030921 | Cascaded cold cathode field emission devices Field emission devices are cascaded in multiple stages, such that certain structures function as electrodes for field emission devices of differing stages.... | 07/09/1991 |
| 4163198 | Audio amplifier An audio amplifier including a non-inverting amplifier stage that provides linear amplification without loop feedback for low distortion audio systems. The amplifier stage includes a triode vacuum tube or a triode connected pentode vacuum tube and a P cha... | 07/31/1979 |
| 3999139 | Monolithic alternately stacked IF amplifier The IF amplifier combines the high frequency and low noise figure characteristics of a cascode stage with the large signal handling capability and accurate gain control of a direct emitter coupled amplifier controlled by a constant current source. The amp... | 12/21/1976 |
