Since then, solid-state devices have all but completely taken over.

However, vacuum tubes played a leading role in the field of microwave and high power transmission as well as television receivers until the middle of the 1980s. The next big technological step took several decades to appear, when the first working point-contact transistor was invented by John Bardeen and Walter Houser Brattain at Bell Labs in 1947.

The early growth of electronics was rapid, and by the 1920s, commercial radio broadcasting and communications were becoming widespread and electronic amplifiers were being used in such diverse applications as long-distance telephony and the music recording industry. Vacuum tubes (Thermionic valves) were the first active electronic components which controlled current flow by influencing the flow of individual electrons, They were responsible for the electronics revolution of the first half of the twentieth century, They enabled the construction of equipment that used current amplification and rectification to give us radio, television, radar, long-distance telephony and much more. Practical applications started with the invention of the diode by Ambrose Fleming and the triode by Lee De Forest in the early 1900s, which made the detection of small electrical voltages such as radio signals from a radio antenna possible with a non-mechanical device. The identification of the electron in 1897, along with the subsequent invention of the vacuum tube which could amplify and rectify small electrical signals, inaugurated the field of electronics and the electron age. One of the earliest Audion radio receivers, constructed by De Forest in 1914.Įlectronics has hugely influenced the development of modern society.

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