“YALT, YALT, YALT…, or “Yet Another LED Tester”. There are already several different types of LED testers on Instructables. So why another? Well, it started after I accidentally bumped over one of my component drawers. The drawer was filled with four different color LEDs. And to make matters even worse, all the LEDs were high-bright transparent LEDs. With about 400 LEDS to resort, I decided to build a tester to assist me.”