electron tube Also known as a valve, an evacuated glass or metal tube which may contain gas at low pressure, through which electrons flow between two or more electrodes. A heated filament, the cathode, emits electrons which are attracted to the positively-charged anode. By varying the voltage on intermediate (grid) electrodes, the electron flow can be regulated and the tube made to work as an amplifier. Related categories ELECTRICITY AND MAGNETISM ELECTRONICS AND SEMICONDUCTORS Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |