Diode
In electronics, a vacuum tube or thermionic valve, is a device generally used to amplify, switch or otherwise modify, a signal by controlling the movement of electrons in an evacuated space.
For most purposes, the vacuum tube has been replaced by the much smaller, less power-hungry, and less expensive transistor, either as a discrete device or in an integrated circuit. However, tubes are still used in specialized applications, such as in high-end audio systems and high power RF transmitters. Cathode ray tubes are still used as a display device in television sets and computer monitors (although they face serious competition from LCD and plasma displays), and magnetrons are the source of microwaves in microwave ovens.
Diode
In electronics, a vacuum tube or thermionic valve, is a device generally used to amplify, switch or otherwise modify, a signal by controlling the movement of electrons in an evacuated space.
For most purposes, the vacuum tube has been replaced by the much smaller, less power-hungry, and less expensive transistor, either as a discrete device or in an integrated circuit. However, tubes are still used in specialized applications, such as in high-end audio systems and high power RF transmitters. Cathode ray tubes are still used as a display device in television sets and computer monitors (although they face serious competition from LCD and plasma displays), and magnetrons are the source of microwaves in microwave ovens.