Also called an electron tube vacuum tube or even light, is an active electronic component, generally used as an amplifier. The vacuum tube rectifier or amplifier has been replaced in many applications in different semiconductors, but to date remains irreplaceable in some areas such as high power amplifier or hyperfréquences.Les electron tubes means the components that use electrodes, placed in a vacuum or a gas, isolated from each other in this medium, and comprising at least one source Electron. Durable temperature isolates all from the outside. Although the envelope is usually glass, power tubes often use ceramic and metal. The electrodes are connected to terminals that pass through the passages sealed envelope. On most tubes, terminations are designed to be pin installed in a vacuum tube holder for easy replacement

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