This 1960s Japanese receiver uses 6 germanium transistors, being powered by a 6 V voltage obtained from large batteries. The circuit is for the medium wave range of the superheterodyne type.
Found in Radio Electronics this circuit uses a fotodiac to drive a triac. The circuit can use...
This circuit is from an old English documentation. It is intended for coupling a microphone to the...
Here is an interesting circuit to be used in physics demonstrations involving energy...