Review on Lysignal Channel Interface Optocoupler Protection by Frank Harwood

Like many others, I surf the internet before building anything, mostly because many of the modules I need can be bought off the shelf for significantly less than I could assemble them myself, and without great effort! This is one of them: an 8-channel relay board that connects to the Arduino and even has optocoupler protection! And it's less than 8 dollars! (Ok, it's not much less than $8, but you get the idea). Saves me time and money which is good! And yet it works perfectly. Highly recommended.