Definition
A glow tube is a type of electronic vacuum tube that contains gas, typically neon, which emits light when ionized by an electric current ๐ก. It's similar in function to a glow lamp, but often larger and used for more significant displays. They were common in early digital displays before LEDs became widespread. Think of it like a vintage digital number display. Each tube often represents a digit or character. They have a distinctive warm, orange glow. Now mostly replaced by more efficient technologies, they still have a retro appeal.