Using a capacitor as a sensor, this circuit was found in the 1989 Radio Electronics Experimenter magazine. The circuit must be assembled in a shielded box.
This is the patent for the zener diode regulator circuit by David B. Dean of Austin published in...
This simple 10-position roulette circuit with the 4017 found a 1987 documentation. The circuit can...
This circuit was found in a 1986 documentation. The circuit has a common configuration with the...