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.
We found this circuit in a Radio Electronics magazine from December 1969. The circuit uses a...
We found this circuit in a 1991 publication. It is intended for low-impedance microphones,...
This circuit can be used in the car to convert the 12 V from the battery in 6 or 9 V up to 2 A....