Vacuum Tubes: Episode 1 - The Basics and the Diode
Vacuum Tube Diode (1981)
Vacuum tube diode ( principle of operation and internal construction )
Vacuum Diode(Easy Explain)
In electronics, a vacuum tube, an electron tube, or just a tube, or valve is a device that controls electric current between electrodes in an evacuated container.
Vacuum tubes mostly rely on thermionic emission of electrons from a hot filament or a heated cathode. This type is called a thermionic tube or thermionic valve. A phototube, however, achieves electron emission through the photoelectric effect. Not all electronic circuit valves/electron tubes are vacuum tubes (evacuated); gas-filled tubes are similar devices containing a gas, typically at low pressure, which exploit phenomena related to electric discharge in gases, usually without a heater.