This circuit is used to turn on the headlights when it gets dark. The circuit is from an Electronics Now magazine from October 1998. The power transistor must be equipped with a heatsink.
The Buck-type DC-DC converter (voltage lowerer) shown in figure 11 is suggested by Analog Devices...
This circuit can be used to directly control direct current loads or higher alternating current loads...
This circuit can turn-on (only) a load (relay or lamp) when S1 is pressed. The circuit can be used as...