Laser (1):

Over the last few years, a variety of low-power Helium-Neon (HeNe) laser tubes has founds its way in into the electronics surplus trade circuit. Unfortunately, these laser tubes are nearly always sold without a suitable power supply, which, being a high-voltage unit, is not so simple to construct. In this two-instalment article we describe a power supply for the popular 2-mW class of laser tubes, a beam steering system based on mirror galvanometers and last but not least a state-of-the-art modulator that enables laser patterns to be created with the aid of a music signal. The circuits described are designed and marketed as kits by ELV.