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 simple 10-position roulette circuit with the 4017 found a 1987 documentation. The circuit can...
This small auxiliary amplifier was found in a Radio Electronics from May 1958. Power is supplied with...
According to the article in Radio Electronics from April 1986, it would be possible to detect...