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Information about Triode

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Structure of a vacuum tube triode
A triode is an electronic device having three active electrodes. The term most commonly applies to a vacuum tube (or valve in British English) with three elements: the filament or cathode, the grid, and the plate or anode. The triode vacuum tube was the first electrical amplification device.

Invention

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Lee De Forest "Triode" Audion tube from 1908
The original three-element device was patented in 1908 by Lee De Forest who developed it from his original two-element 1906 Audion. The Audion did incorporate, in a crude form, the key principle of allowing amplification. However it was not until around 1912 that other researchers, while attempting to improve the service life of the audion, stumbled on the principle of the true vacuum tube. The name triode appeared later, when it became necessary to distinguish it from other generic kinds of vacuum tubes with more elements (diodes, tetrodes, pentodes). The original Audion tubes were not vacuum tubes however, as they deliberately contained some gas at low pressure. The name triode is only applied to vacuum tubes.

Operation

The principle of its operation is that, as with a thermionic diode, the heated filament causes a flow of electrons that are attracted to the plate and create a current flow. Applying a negative charge to the control grid will tend to repel some of the (also negatively charged) electrons back towards the filament: the larger the charge on the grid, the smaller the current flow to the plate. If an AC signal is superimposed on the DC bias of the grid, an amplified version of the AC signal appears in the plate circuit.

Applications

Although triodes are now largely obsolete in consumer electronics, having been replaced by the transistor, triodes continue to be used in certain high-end and professional audio applications, as well as in microphone preamplifiers and electric guitar amplifiers.

Some guitarists routinely drive their amplifiers to the point of saturation, in order to produce a desired distortion tone. Many people prefer the sound of triodes in such an application, since the distortion of a tube amplifier, which has a "soft" saturation characteristic, can be more pleasing to the ear than that of a typical solid-state amplifier, which is linear up to the limits of its supply voltage and then clips abruptly.

See also

vacuum tube, electron tube (inside North America), thermionic valve, or just valve (elsewhere); is a device used to amplify, switch, otherwise modify, or create an electrical signal by controlling the movement of electrons in a low-pressure space, often not
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An electrical filament is a thread of metal, usually tungsten, which is used to convert electricity into light in incandescent light bulbs (as developed in 1878 by Joseph Wilson Swan, among others), and into heat in vacuum tube devices.
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A cathode is an electrode through which (positive) electric current flows out of a polarized electrical device. Mnemonic: CCD (Cathode Current Departs). To dispel a common misconception, often incorrectly inferred from the correct fact that in all electrochemical
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The control grid is an electrode used in thermionic valves (vacuum tubes) used to modulate the flow of electrons in the cathode to anode or plate circuit.

Operation


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Plate may refer to:
  • Plate (dishware)
  • Plate (structures), in mechanics
  • A flat piece of metal used in orthopedics to connect the two parts of a broken bone, such as a dynamic compression plate
  • Plate armor, body armor made of metal plates

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An anode is an electrode through which (positive) electric current flows into a polarized electrical device. Mnemonic: ACE (Anode Current Enters).
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amplifier is any device that will use a small amount of energy and convert it to a larger amount of energy. In popular use, the term today usually refers to an electronic amplifier, often as in audio applications.
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19th century - 20th century - 21st century
1870s  1880s  1890s  - 1900s -  1910s  1920s  1930s
1905 1906 1907 - 1908 - 1909 1910 1911

Year 1908 (MCMVIII
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Lee De Forest, (August 26, 1873 – June 30, 1961) was an American inventor with over 300 patents to his credit. De Forest invented the Audion, a vacuum tube that takes relatively weak electrical signals and amplifies them.
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The Audion is an electronic amplifier device invented by Lee De Forest in 1906. It was the forerunner of what is generally known as a triode today, in which the flow of current from the filament to the plate was controlled by a third element, the grid.
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Audion may be
  • the Audion tube, a wireless signal detector device invented by Lee De Forest in 1906.
  • Audion (software), a freeware media player for Apple Macintosh created by Panic.
  • Audion (band), an indie rock band from Columbus, Ohio.

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diode is a component that restricts the directional flow of charge carriers. Essentially, a diode allows an electric current to flow in one direction, but blocks it in the opposite direction. Thus, the diode can be thought of as an electronic version of a check valve.
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tetrode is an electronic device having four active electrodes. The term most commonly applies to a two-grid vacuum tube. It has four electrodes instead of three, as in the case of a triode.

Grids

The first grid of a tetrode, i.e.
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A pentode is an electronic device having five active electrodes. The term most commonly applies to a three-grid vacuum tube, which was invented by the Dutchman Bernhard D.H. Tellegen in 1926.
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diode is a component that restricts the directional flow of charge carriers. Essentially, a diode allows an electric current to flow in one direction, but blocks it in the opposite direction. Thus, the diode can be thought of as an electronic version of a check valve.
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Electron

Theoretical estimates of the electron density for the first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density
Composition: Elementary particle
Family: Fermion
Group: Lepton
Generation: First
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Consumer electronics include electronic equipment intended for everyday use. Consumer electronics are most often used in entertainment, communications and office productivity.
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A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. The transistor is the fundamental building block of the circuitry in computers, cellular phones, and all other modern electronic devices.
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High-end audio is a term used to describe equipment that is purported by the manufacturers to be the best, regardless of the price.

Definition of 'high-end'

High-end audio
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Professional audio, also 'pro audio', can be used a term to refer to both a type of audio equipment as well as a type of audio engineering application.

Professional audio equipment
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preamplifier (preamp) is an electronic amplifier which precedes another amplifier to prepare an electronic signal for further amplification or processing.

Description

In general, the function of a preamp is to amplify a low level signal to line-level.
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A guitar amplifier is an electronic amplifier designed for use with an electric or electronic musical instrument, such as an electric guitar.

History

The first electronic instrument amplifiers were designed for use with electric guitars.
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Saturation current is a term used to describe a limit to the amount of current that can flow in an electronic circuit or device. As the voltage applied to a circuit is increased, the current flow will increase proportionately until the saturation current is achieved, at which point
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The term solid state was introduced in the 1960s to describe electronic devices whose circuits contained neither vacuum tubes nor mechanical devices such as relays, as transistors replaced vacuum tubes in most consumer electronics.
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Clipping is a form of waveform distortion that occurs when an amplifier is overdriven, which happens through attempts to increase the voltage or current beyond its threshold of power.
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vacuum tube, electron tube (inside North America), thermionic valve, or just valve (elsewhere); is a device used to amplify, switch, otherwise modify, or create an electrical signal by controlling the movement of electrons in a low-pressure space, often not
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This is a list of vacuum tubes:

American designation (with European equivalents)

RETMA tube designation

0

  • 0Z4 Full-Wave Gas Rectifier

2 volt heater/filament tubes

  • 2B7 Twin-diode remote-cutoff pentode

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Since 2000 each year the "European Triode Festival" (ETF) has been held in various venues in Europe (the first three events were called "Aarhus Triode Festival" aka "ATF". The ETF focuses on do-it-yourself audio valve amplifiers using triode vacuum tubes, and brings together some 100 high
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