Found in a 1965 CQ magazine, this circuit uses period components. The unijunction transistor can be a 2N2646 and the relay has voltage according to the supply.
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...