Triode
The fluidic triode is an amplification device that uses a fluid to convey the signal.
Although much studied in the laboratory they have few practical applications. Many expect them to be key elements of nanotechnology.
Fluidic triodes were used as the final stage in the main Public Address system at the 1964 New York World's Fair.
The Fluidic Triode was invented in 1962 by Murray O. Meetze, Jr., a high school student in Heath Springs, S.C. He also built a fluid diode, a fluid oscillator and a variety of hydraulic "circuits," including one that has no electronic counterpart. As a result he was invited to the National Science Fair, held this year at the Seattle Century 21 Exposition. There his project won an award.
- (Scientific American, Aug. 1962)
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