I had to spin the shaft really fast to get the LED to light up, and now that I converted the generator (was a CD-ROM drive motor) by adding the Joule Thief to the back, all I have to do is spin the shaft gently and the LED lights up brightly. It’s a big difference; it’s much easier.
The coil uses a T231212T toroid core from Surplus Sales. I ‘trifilar’ wound it with 6 inches of three conductors: two were 28 AWG in parallel for the primary and a single 30 AWG for the feedback. The transistor is a BC337-40 and the resistor is a 2000 ohm, 1%, 1/4W I salvaged from a PC board. I could have made all of it fit on the back of the motor if I had cut the leads shorter.
I was trying to come up with a way to mount the tiny generator onto something hand held, and put a crank on it to allow charging up a super capacitor. I bought one of those hand crank flashlights and they don’t work; the LED goes out as soon as the cranking is stopped. I think there must be a better way to charge up a multiple farad capacitor so that the LED will light brightly for several minutes.
Back to experimenting…
Try your joule thief on the setup shown here:
http://peswiki.com/index.php/Directory:Raul_Melendres%27_Free_Energy_Cell_Phone_Charger