How Electromechanical Relays Work - DC to Daylight

In this theory-based episode, we take a look at the evolution of the relay, how it changed telegraphy, and how to actuate a relay safely from a low-current source like a microcontroller. The method Derek typically uses to select the proper base resistor for a given BJT transistor is presented, as well as why you always see a freewheel protection diode across the relay coil; the resulting waveform, with and without protection diode, are viewed on the oscilloscope. https://bit.ly/37dbe0p Engage with the element14 presents team on the element14 Community - suggest builds, find project files and behind the scenes video: https://bit.ly/3tmdewv Visit the element14 Community for more great activities and free hardware: https://bit.ly/3q6YMpu Tech Spotlights: https://bit.ly/3qPrDhM RoadTest and Reviews: https://bit.ly/3pV5Bux Project14: https://bit.ly/31wbnJY #0:00 Welcome to DC to Daylight #1:06 Relays #2:53 Telegraph Relay #5:36 Drive a Relay from a Microcontroller #9:16 Circuit #10:33 Scope #12:17 Give Your Feedback #relays #electromechanical #electromagnet #transistor