These wave-detecting devices may be divided into two classes: (i) potential operated detectors, and (ii) current operated detectors.
A fourth class of electric wave detector comprises the thermal detectors which operate in virtue of the fact that electric oscillations create heat in a fine wire through which they pass.
The thermal G G detectors are especially useful for the purpose of quantitative measurements, because they indicate the true effective or square root of mean square value of the current or train of oscillations passing through the hot wire.
Plumbago, and molybdenite and copper possess similar powers, and can be used as detectors in radio-telegraphy.
How would you define detectors? Add your definition here.