What Is Thermionic Valve?

A vacuum tube, electron tube, valve, or tube, is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied.

How does a thermionic valve work?

The basic working principle of a vacuum tube is a phenomenon called thermionic emission. It works like this: you heat up a metal, and the thermal energy knocks some electrons loose. ... When the cathode is heated, and a positive voltage is applied to the anode, electrons can flow from the cathode to the anode.

What is the meaning of thermionic?

: relating to, using, or being the emission of charged particles (such as electrons) by an incandescent material.