Found in a 73 magazine for radio amateurs of the 90s, this circuit provides a 2 kV voltage with 7.5 mA of current for HeNe laser.
With this circuit it is possible to use a common hair dryer as a hand dryer. The circuit is timed...
This circuit was obtained from an English magazine from 1979, but can be easily assembled today...
This circuit was obtained in a 1975 magazine, but it can be easily assembled using BC548...