This 1970s RCA circuit can be triggered by light or dark, depending on how the LDR is connected. The controlled load depends on the triac.
This circuit was obtained from an old documentation, but as it uses still current components it can be...
This audio circuit has an output power of 1 W. We found it in the Radio Electronics magazine of...
This circuit that uses only discrete components (transistors) mimics the sound of an American...