This 4-tube circuit was found on a Radio Craft from December 1945. The circuit has excellent sensitivity. Power comes from a power supply with a transformer.
Found in a Popular Electronics from the 90s, this circuit provides 100 W of power. The power...
I found this simple basic circuit of rhythmic light in a 1980 documentation. We warn you to be...
This circuit was found in Popular Electronics from 1992. The circuit has steps determined by...