Joule Thief

Hi, today I'm posting about Joule Thief.
Joule thief is a small voltage booster.
Here is a video that explain how it works:

If you'd like to build one here is the parts list:
-transistor 2n3904(or equivalent like 2n2222)
-ferrite ring (toroid)
-LED
-1k ohm resistor
-some wires

Here is a simple diagram:

 

Here are other photos of the project:

 I hope you like this post, if you have any question comment or send me an email to damianoandre@gmail.com

Bye, Dami