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.
We found this circuit in a documentation on active filters from 1977. The gain of this circuit is...
The touch sensor of this circuit consists of a single plate that must be touched to obtain an...
The integrated circuit used in this project is not common today, as it was obtained in the Linear...