Solar intercom (CB20503E)

This circuit can be used in demonstrations or science fairs. The circuit uses headphones and can be powered by solar cells.

Flip Flop with transistors configured as SCRs (CB23688E)
This interesting circuit from Radio Elecronics from October 1965 shows a flip-flop or bistable with...
Constant light (CB12750E)
The basic idea of the circuit shown in the figure is to increase the brightness of an ordinary...
12V Regulator (CB21178E)
Found in an American documentation, this regulator supplies a current according to the integrated...