1 Tutorial: How to design a transistor circuit that controls low-power devices
A tutorial on using a transistor to switch a load that an Arduino pin cannot drive directly, commonly suggested for relays, motors and LED strips.
Topic
relays
9 videos. Ranked by independent recommendations, not by views.
2 Raspberry Pi Automated lights with 8 channel relay, PIR motion sensor
A short tutorial on driving a relay from a Raspberry Pi to switch lights, adaptable to timers or sensors.
3 Raspberry Pi: 4-channel Relay step-by-step with example scripts for home automation
Shows a Raspberry Pi switching relays from its GPIO pins through a web page, with PHP calling Python scripts, often linked for home automation.
4 Harry Porter's Relay Computer
A demonstration of a computer built entirely from relays, linked both as a serious example of relay logic and as a tongue in cheek extreme.
5 Use Arduino to Switch Power On and Off!
A beginner relay tutorial showing an Arduino switching power to a load, though one commenter questions driving the relay straight from a pin.
6 Raspberry Pi - (Relay) Controlling mains electric
A Raspberry Pi demonstration of switching a mains lamp through a relay board, recommended as a clear explanation for anyone wanting to drive bigger loads from GPIO.
7 Back EMF High Voltage Spikes on the Oscilloscope - Part 1
A scope demonstration of the voltage spike an inductor or relay coil produces when switched off, used to explain why flyback diodes matter.
8 Solid State Relay || DIY or Buy
GreatScott! explains solid state relays and why triac based AC units cannot switch DC, cited for its notes on control voltage and failure modes.
9 AT&T Archives: The Step-By-Step Switch
Archive film explaining electromechanical step-by-step telephone switches, recommended for understanding how exchanges routed calls before digital electronics.
