4BC8 Tubes

BC8 is a family of glass sandwich tubes developed by RCA. They were very popular in the 1950s and 1960s for use in electronic equipment. The BC8 tubes consist of two concentric glass tubes filled with a special mesh of electrodes inside. The tubes are then hermetically sealed and are both rugged and reliable. The inner tube contains two grids, one grid being the cathode and the other the anode. A control grid sits near the combination of these two grids and is used to control current flow through the tube. The outer tube has an electron-receiving plate and acts as a shield. This prevents any unwanted fields from interfering with the operation of the tube. The BC8 tubes are used in several types of circuits, such as oscillators, modulators, switches and amplifiers. The most common applications of the BC8 tubes are in television receivers, radio receivers and high-power amplifiers. The BC8 tubes are also well-suited for switching and control circuits as they have a wide current-handling range and good electrical characteristics. The BC8 family of tubes is still in use in many types of electronics today.