The metal detector circuit shown here must represent the limits of simplicity for a metal detector, yet the design works surprisingly well. It uses just one 40106 hex Schmitt inverter IC, a capacitor ...

Compared to the simple diode needed to demodulate AM radio signals, the detector circuits used for FM are slightly more complicated. Wrapping your head around phase detectors, ratio detectors, ...

A single-photon detector (SPD) is sensitive to incidence of individual quanta of light and has many applications in photonics, such as fluorescence measurements, laser ranging, optical time-domain ...