Found in an American documentation from 1968, this circuit senses the temperature through an infrared sensor of the time. The indicator is analog.
We found this circuit in a 1980s publication. The circuit, however, makes use of common components...
This symmetrical source was obtained from Popular Electronics from February 1979. Transistor Q1...
This medium wave radio with 7 germanium transistors was manufactured in Japan in the 1960s. Its...