This circuit allows the activation of a remote telephone bell made with a common piezoelectric capsule. The circuit does not need power, as it is powered by the line call signal itself.
For triggering high-powered loads connected to the power grid, nothing better than using TRIACs. For...
This simple circuit tests electrolytic capacitors from 1 uF with a working voltage above 12 V. The...
This circuit detects changes in magnetic flux in a coil as an external magnetic field moves. The...