This circuit, found in a 1958 magazine, is for reference only, since the components are not easy to find today. The transistors are germanium types and power supply is made by common cells.
This circuit was obtained in a 1984 publication, but it can be assembled using BC548 for TR1 and...
This circuit was found in an American documentation from 1969. The circuit memorizes when a...
This counter was found in the November 19983 issue of Radio Electronics magazine. The power supply...