This circuit can be used to generate percussion sounds such as bell, triangle, etc. The circuit must be powered by symmetrical source and the triggering is by external pulse.
This voltage controlled oscillator uses a varicap to change the frequency. Usin a 100 turns coil...
This circuit was obtained in a documentation from the National Bureau of Standards of 1968. The...
This circuit turns on your car's backlight when a vehicle coming from behind gets too close to it...