101-Led Wreath

Step 7 Crossed Wires

We're going to get our wires crossed, on purpose.

Remember how the wreath looked woven? That effect comes from crossing two strands of the four-led sections you made earlier.

And remember how the voltage started high at the top and went to zero at the bottom? And at at the middle, the voltage was, well, in the middle?

We're going to make the X's by hooking the middle spots of each strand of four LEDs together, and since the middle at the same voltage, it's not going to cause any sparks. And here's the twist you were promised earlier! In each X, hook one set of LEDs up backwards.

How can we do this? Didn't I say we have to get the anode and cathodes all the same way to make LEDs work?

Yes, but hold on: If you start at 8.4V and go down to zero, the voltage in the middle is 4.2V, and if you start at 0 and go up to 8.4V, the in the middle, the voltage is still 4.2V. So we're still going to hook plus to the plus side and minus to the minus side, but we're doing it in a fancy way.

Read on...