This circuit takes advantage of the noise generated at the reverse biased junction of a germanium diode. Other types of diodes can be used. The signal is weak.
Found in American 90’s documentation, this circuit generates 300 Hz depending on the capacitors...
According to what is said, the bugs are the female insects (mosquitoes, muriçocas and others)....
Found in a 90s nHands On Electronics, this circuit triggers a relay that shuts off the load when...