Description

A cone-shaped glass tube that gradually tapers out to a round flat end on one side. The sides of the glass are tinted grey on the inside, and the screen is tinted white on the inside. The base of the tube is covered with a brass-colored metal base with metal pins sticking out of it.

Cathode ray tubes (CRT) are the screen component for most early televisions and oscilloscopes. In them, an electron can in the center of the tube produces a stream of electrons, which are accelerated towards the screen. As they travel, they pass through an electric field that moves them to a particular point in the screen at the other end of the tube. The inside of the screen is painted with a fluorescent material that emits light when struck by electrons, which are visible on the other side of the screen. This tube was likely a replacement for an oscilloscope screen. Unlike CRTs for televisions (where the electron stream rapidly sweeps across the screen in horizontal rows to create a moving picture), those used in oscilloscopes correlate the electrical signal from the system being analyzed into a visualization on the screen.