This circuit can keep a set of lamps on for up to 1 minute, time given by C2 and R2 that can be changed. The load depends on the relay. The circuit is old, from 1988 documentation, but totally viable today.
Found in a 1967 Delco documentation, this circuit can deliver power from 40 to 50 W at 8-ohm load....
This circuit allows you to use the parallel PC interface to control LEDs. The circuit was found in...
This traditional multivibrator configuration uses an LDR as a sensor. The circuit emits sound when...