Make Electronics-Exp 8d

THE OSCILLATING RELAY WITH CAPACITOR with 1 LED removed: Compared to experiment 8c we removed the blue LED and kept the red LED. It means that one of the switches inside the relay is not connected to anything (used to be connected to the blue LED). The only way now for the current to go through the circuit is through the switch inside the relay that is connected to the red LED. Before closing the switch to the right of the relay (and capacitor) the current can only go through 1 path and the red LED stays on all the time as the coil of the relay is not energized and the relay stays in a relaxed state allowing the current to flow through. Once we close the switch, the capacitor charges immediately and slowly releases current thereby energizing the coil inside the relay. While the coil inside the relay stays energized, current cannot pass through. The LED light slowly fades as the voltage in the capacitor diminishes. When there is not enough current left in the capacitor to keep the coil inside the relay energized, the relay goes back to a relaxed state allowing the current to flow through it once again. As it happens the LED becomes bright red again for an instant and then we repeat the cycle and it starts to slowly fade away once more.

published 7 years ago