Joule Thief Shorted.10 times more light.
This joule thief works much better when the ferrite core is shorted with a wire – a magnet or a capacitor. I adjust the trim capacitor for the best resonance. The magnet must be adjusted in strength. Here are 9 pieces best. Try it on other jouel thief and they oscillate much better. 10 times more light on LEDs.