21. One triode operated in a conventional oscillator circuit. 22. It replaced the use of power triodes in public-address amplifiers almost overnight. 23. Miller capacitance was identified in 1920 in triode vacuum tubes by John Milton Miller. 24. However the triode vacuum tube oscillator performed poorly above 300 MHz because of interelectrode capacitance. 25. Triodes and a few tetrodes were made.26. Triodes are used for amplifiers and oscillators.27. This eventually became known as the triode . 28. The triode vacuum tube made it possible to build amplifiers for broadcasting and for receivers. 29. The final output stage had a pair of water-cooled 4220-B triodes . 30. This was actually four triodes and their associated circuit tightly packaged in one glass envelope.
