This 80's circuit turns off a TV or other appliance after a set time. The base is a 555 IC and the relay is according the supply.
This second-order filter was found in a documentation from the 90's. It can be implemented with...
To implement this function, we need a relay with double contacts, as shown in the figure. With a...
In this circuit the relay triggers on when light falls onto the sensor, a common LDR. Power supply...