The Vacuum Tube

A vacuum tube is an electronic device that controls the flow of electrical signals using a sealed glass container with removed air. Inside, it contains electrodes like a filament (heater), a control grid, and a plate (anode). When the filament heats up, it releases electrons, creating a flow toward the plate. The control grid modulates this current, allowing the tube to amplify signals or switch electrical paths. Vacuum tubes were essential in early radios, computers, and electronics before being replaced by transistors. They act as amplifiers or switches in electronic circuits, relying on vacuum conditions to function effectively.