Found in an old Popular Electronics this circuit can also be adapted to be used as a shield. In this version the control can trigger loads from the light that falls on an LDR.
With this circuit it is possible to divide the frequency of a rectangular signal by values between 2...
This circuit, which we find in a documentation from the 70s, filters out the Ru [occurring in...
This circuit simulates the call tone of a telephone. The transducer is a high impedance capsule, and...