This simple circuit was found in a Japanese magazine in 1967. The circuit is listening on a headset and the coil is 50 + 50 turns of wire 28 or thinner on a ferrite rod.
A touch or the simple approach of the sensor (metal plate) causes this circuit to emit a sound...
The circuit shown in the figure produces pulses of high intensity light at a frequency that...
This circuit was found in an English publication from 1976. It generates sequential signals in the...