Self-maintained gaseous discharge in Pohl's discharge tube

Principle

A gas discharge tube is connected to a vacuum pump. Applying a high voltage causes a variety of light phenomena in the tube, which are dependent on the pressure at that moment. The 0...10-kV high-voltage power supply used here (13670-93) is particularly appropriate for operating gas discharge tubes, since it not only supplies the initial current needed to safely trigger the effects, but also possesses built-in current limiting, which prevents it from presenting a hazard as defined by radiation protection legislation.