This circuit was obtained from the March 1994 Electronics Now magazine. The circuit uses a common transistor which can be a low noise type such as the BC549.
With the first project we present, a relay is activated in the presence of light. We can use it as...
The ZN414 is an uncommon integrated circuit currently used in the elaboration of very simple MW...
This circuit can be used to detect the signals from the previous circuit or from any radio...