Some of these tubes contain small quantities of Cesium-137, Cobalt-60, Radium-226, Krypton-85. The radioactive elements have been added to increase the electronic response by improving the internal ionization processes.
A story of making a DIY Digital Geiger counter circuit, that can be used with several tubes. Add an enc28j60 Ethernet module and use the data to create graphs available online!
The device consists of a hot cathode (filaments), anodes (phosphor) and grids encased in a glass envelope under a high vacuum condition. The cathode is made up of fine tungsten wires, coated by alkaline earth metal oxides, which emit electrons when heated by an electric current.
A hydrogen thyratron is a device capable of switching big amounts of energy. The major advantage over other thyratrons is that the deionization time is reduced by using the hydrogen gas, generated in a small reservoir inside the tube, from a metallic Hydride.