Introduction: Rainbow Light

This set-by-set guide will show you how to construct the Rainbow Light kit available at

Step 1: First the Brain....

First, place the microcontroller on the printed circuit board. The microcontroller will go on the rectangle outline in the middle of the board. As you can see in the first picture, one end on the rectangle has a notch. Also, notice in the second picture that the microcontroller has a dot on one end. Make sure the dot on the microcontroller and notch on printer circuit board are on the same side, just like the pictures shown.

Now you can solder the microcontroller in.

Step 2: Lights!

It wouldn't be much fun without the LED so let's add that next!

You can see the outline for the LED on the PCB board. It is a circle with a flat side. That flat side is important. The LED also has a flat side, so be sure to match the flat side of the LED to the flat side on the LED outline on the board.

Spread the leads out as shown in the second and third pictures. The long lead goes on the hole with the square outline. Double check that the flat side of the LED matches the flat side on the LED outline on the board.

Now you can solder the LED in place and trim the excess leads.

Step 3: Power Up!

We have the brain, the light and now we need some power!

Solder the red wire of the 2xAA battery holder in the hole on the board labeled "v+". Next, solder the black wire of the battery holder in the hole beside it labeled "g".

If you put batteries in the holder, the kit should light up and start rotating through the rainbow!

Step 4: Everything Changes...

Last, you can add the included pin header in the last two holes to use as switch. If you bridge the pins with a paperclip, the lights will cycle from rainbow -> red -> green -> blue -> sleep -> rainbow.

You can add you own external switch too! Just add a momentary push button switch between the "sw" and "g" pins.

If you use another power source, keep it a 3.3v or below. A CR2032 works great (hint, hint).

That is all! Thanks for reading!

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