Make Electronics-Exp 8c

THE OSCILLATING RELAY WITH CAPACITOR: Here we build on the previous experiment (8b) and add a 1mF capacitor in parallel with the coil of the relay. When closing the switch to the right of the relay's coil, the capacitor charges very quickly and discharges gradually therefore keeping the the relay in its non-relaxed state whereby the blue LED is on. Every time the capacitor recharges (it's quick) the relay will go back to its relaxed state and the red LED will flicker on very briefly. The cycle then repeats itself with the blued LED on for a while followed by a quick flicker of the red LED. Here I use a simulation speed of 20ms/s, feel free to play around with it. At a lower speed it is easier to see the red LED flicker but you have to wait longer for it. At higher speeds it will be too fast to see the red LED flicker but it will be easier to see the switch inside the relay go back and forth on the other hand. I changed the current of the red LED to 8mA (from the typical 20mA) to make it easier to see when it flickers briefly.

published 7 years ago