Lately I've been developing a fondness of blinking lights. Yes, I'm insane and relatively unstable. But I can stare at a blinking light for hours. So to support my habit I've been learning how to build them myself. I got my first blinking light in my optical mouse's box (The mouse ROCKS!) And it's been intermittent ecstasy since. Then in my electronics class I was given the schematics for the construction of a 2-LED alternating red/green circuit. So I hacked the circuit just a bit and made a nifty little blinking light that runs on a nine volt battery. The thing is wasteful by my standards, (5 mA peak current draw, which at that level SHOULD have a minimum battery life of 100 hours, the minimum current is MUCH lower so I should get quite a bit of time out of it...)

This is a picture of the device that started my obsession. Now in and of itself it seems like a stupid little LED on a small board with a surface mount timing controller. And in fact that's what it is. But for whatever reason I decided to take it with me to school and put it in my gym locker. Turns out someone thought it was a bomb... (What kind of a moron does it take to mistake a blinking light for an explosive device?)

This is my first home made blinkey. I got the schematic from my electronics instructor but it was for 2 bidirectional LEDs and it drew alot of power, (mostly because there was a direct channel for the current to flow through) So I modified it to only have one monodirectional LED, which proved to be incredibly effective at lowering the power drain.

Get the schematic for the home made blinker.

The project is based on the 555 TTL timer. By changing the values of the resistors and the capacitor the timing can be changed. The values I've selected are half based on my electronics teacher's inital schematic. After that I played with it and got the values there. The blink rate is roughly 1 blink every .75 seconds. My setup has an on/off ratio of 1/7. So it's a pretty quick blink. But i like it more then the On.... Off.... On.... Off...