This capacitive sensor that operates with a high frequency oscillator was found in Radio Electronics from the 90's. The circuit operates around 300 kHz.
This 0.5 Hz filter was found in the December 1990 issue of Radio Electronics magazine. The power...
This circuit was obtained in the SGS manual of linear integrated circuits of 1982. The maximum...
This circuit allows linear brightness control of an LED from an input voltage. The power supply must...