How Does a Vacuum Tube Amplifier Work?
The Parts To know how a vacuum tube amplifier works, one first has to be familiar with the parts. Each vacuum tube has two diodes, a glass envelope (the tube itself), a plate (which acts as an anode), a filament (which acts like a cathode) and a grid. Electricity An electrical current is applied to the filament in the tube. The electricity can come from a simple battery or it can come from hard wiring on a main circuit. The electricity passes through the first diode and heats up the filament, and some of the electrons in the filament are released because of the extra energy from the heat (electricity). This results in the formation of a space charge, or a negatively charged cloud of electrons, in the vacuum. Attraction to the Plate The electrical current moves back and forth across the grid, which is attached to the plate. This makes the charge of the plate alternate between positive and negative. If the plate within the tube is positively charged, then the negatively charged electrons
