This circuit generates a strong audio tone that scares away mosquitoes. Care must be taken that, due to its potency, it can also cause discomfort to very close people and domestic animals.
This voltage calibrator circuit using a zener diode was found in Radio Electronics magazine from...
The relay of this circuit closes when the position set in P2 is reached by the sensor...
The purpose of this circuit, which we find in an old American documentation, is to allow the...