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To distinguish his device from the Audion he named it the "Pliotron", from the Greek plio (more or extra, in this sense meaning gain, more signal coming out than went in). Essentially, he referred to all his vacuum tube designs as Kenotrons, the Pliotron basically being a specialized type of Kenotron.
Developed from Lee De Forest's 1906 Audion, a partial vacuum tube that added a grid electrode to the thermionic diode (Fleming valve), the triode was the first practical electronic amplifier and the ancestor of other types of vacuum tubes such as the tetrode and pentode.
An audion receiver makes use of a single vacuum tube or transistor to detect and amplify signals. It is so called because it originally used the audion tube as the active element. Unlike a crystal detector or Fleming valve detector, the audion provided amplification of the signal as well as detection.
Lee de Forest was born in 1873 in Council Bluffs, Iowa, the son of Anna Margaret (née Robbins) and Henry Swift DeForest. [1] [2] He was a direct descendant of Jessé de Forest, the leader of a group of Walloon Huguenots who fled Europe in the 17th century due to religious persecution.
The Audion Detector, Audion Amplifier, and the "Oscillion" transmitter had furthered the radio art and the transmission of written or audible speech. In World War I , the De Forest system was a factor in the efficiency of the United States Signal Service, and was also installed by the United States Government in Alaska.
In modern sets, a semiconductor diode is used for the detector, which is much more reliable than a crystal detector and requires no adjustments. [48] [81] [98] Germanium diodes (or sometimes Schottky diodes) are used instead of silicon diodes, because their lower forward voltage drop (roughly 0.3 V compared to 0.6 V [99]) makes them more sensitive.
Eight years later, the ownership of the channel was privatized and its name was changed to The Learning Channel. It showcased documentaries on a variety of topics, like "Paleoworld" and "Amazing ...
The space charge grid tube was the first type of tetrode to appear. In the course of his research into the action of the audion triode tube invented by Edwin Howard Armstrong and Lee de Forest, Irving Langmuir found that the action of the heated thermionic cathode was to create a space charge, or cloud of electrons, around the cathode. <confused: de Forest invented the triode, Armstrong gave a ...