SparkFun Electronics
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Electronik

Controllable Power Outlet by Nate | December 2, 2008 | 22 comments Controlling Big, Mean, Devices Microcontrollers are a ton of fun. Once I got hooked, there was no turning back. Initially playing with sensors and LCDs, I quickly discovered the limits to what a microcontroller could control. A microcontroller's GPIO (general purpose input/output) pins cannot handle higher power requirements. An LED was easy enough, but large power items such as light bulbs, toaster ovens, and blenders required more sneaky circuitry. Something sneaky called a relay: http://www.sparkfun.com/tutorial/Outlet/Outlet-1.jpg In this tutorial we will discuss a small relay board to control the power to a normal AC outlet using 5VDC control.

The folks who brought bakelite cell phone!

How to install a "garage door open" indicator Ever left your garage door open overnight? In addition to being a terrible energy waster, all the tools, bikes, and other stuff are available to thieves - who might even enter your home via the door from your garage to your living quarters. Install a simple indicator which will alert you if you've left the garage door open. Total cost is less than $30-$40, and you can determine exactly where the indicator will be located.