This circuit is from documentation from 1965. However, it can be created with modern transistors. Power comes from two 9 V batteries.
This circuit was found in 1968 General Electric documentation. The circuit uses components from the era...
This circuit was obtained from an English magazine from 1979, but can be easily assembled...
We found this circuit in an American brochure from the 90s. In it we have the way to implement a 4-input...