Ultraviolet Light Pen

Step 3 Penifiy it!

Now we have to transform our beautiful Joule Thief into a pen. This step is relitivly straight forward, in some way, shape or form mount the Joule Thief on a pen with the LED at the tip. A tip; use the longest plastic pen tube that you can find put the actual Joule Thief on the outside of the pen and wire the LED to the tip. Do not connect the battery holder or the switch yet, those come later. be very caeful not to let the LED short it's leads inside the pen tube, if you want, you can insulate them with some heat-shrink tube.

Comments

[wizzywoo]

wat r the dimensions of a ferrite coul please? thx

[junits15]

the demensions aren't too important important, (i don't even know them! :)) what is important is how many times you wind it, the more times you wind it the more juice it can suck from a battery. :)

[wizzywoo]

coil sorry