Vacuum tubes ruled electronics for several decades and while you might think of them as simple devices analogous to a transistor or FET, there were many special types. We’re all familiar with nixie ...

If you’ve ever used an old tube radio, you might be familiar with that mysterious little green display that helps you to tune exactly to a station. That display is called a tuning indicator, or magic ...

A plastic 6-pin base with domed envelope. Donor’s card reads: “Electron-ray tube, glass type, made by the Radio Corporation of America in the early 1930s. An early model of the “magic eye” tuning ...

A plastic 6-pin base with domed envelope. Base stamped: "RCA Cunningham / Made in U.S.A. / Radiotron / [RCA logo]"; on envelope: "6E5". Donor’s card reads: “Electron-ray tube, glass type, made by the ...