We found this circuit in the May 1996 Electronics Now magazine. The relay must have a voltage according to the circuit power supply and a trigger current of no more than 50 mA.
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...