You probably own a pocket calculator. Have you ever looked closely at its screen? Most calculator screens use a seven-segment display, so named because there are 7 "bars" that can be switched on and ...

[Ziggurat29] had been playing around with infrared protocols, and realized he had a spare point-of-sale printer kicking around in his junk box. So he decided to whip up his own calculator infrared ...

[Ziggurat29] had been playing around with infrared protocols, and realized he had a spare point-of-sale printer kicking around in his junk box. So he decided to whip up his own calculator infrared ...