This flip-flop controlled by an LDR-type photocell was found in Radio Electroinics magazine from June 1959. Note that it can be powered from the mains and directly controls a sensitive relay.
Unlike the previous one, this circuit uses only one resistor in the base polarization. The...
This conventional LED effects circuit uses integrated CMOS. Today we can achieve the same effects...
This circuit was found in an old American publication. It makes use of an integrated circuit...