http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2131012_-1
Learn the mysteries of Infrared Light and build a useful kit while you're at it. If you've ever walked into a convenience store and heard the door bell as you walked thru, you likely passed through an infrared beam that when broken, sounded a chime. You can use this on your pet door, refrigerator or somewhere where you'd want to know when someone or something passed by.
looks nice! I made such a thing myself once, but the range was like 2cm xD (I was 16)
vanquisher25 2 weeks ago
now on jameco!
matthewtchernev123 3 months ago