The UVTRON tube is an ultraviolet radiation sensor. In this circuit from Radio Electronics from April 1990 we have a flame detector.
This circuit was discovered in an English publication in 1979. The circuit can still be assembled with...
With this circuit it is possible to obtain a voltage of -5 V from a 5 V source. The circuit is...
This simple experimental circuit using only transistor produces a tone given by C1 and C2. Tone is...