Joule thief 6 LED Flashlight Torch

After reading Evil Mad Scientist Laboratories on how to make a joule thief , I decided to resurrect my 1 AAA cell flashlight torch using the joule thief design .

Step 1: Joule thief 6 LED Flashlight Torch

Picture of Joule thief 6 LED Flashlight Torch
First I made a test rig using a 338 transistor,
6 x 3mm LED's and 11 windings on the toroid.
jamesbond2719711 months ago

hi, can u tell me that in your circut design u have used one led and in your build u have used 7 leds..,can your circut design be used to power 7 leds or if not then what are the modifications.,and can u also tell me that insted of using bc549 transistor which else transistor can be used.??

aalejo11 months ago

i makeone but it make a 71 to 72 turns of windings and omg!!! to much amp that can kill the transtor if i set a voltage to 3.5 to 4.5 vdc well its good joule thiefe but i remod the system i put some diode zener diod damn the system flow good and to powerfull and i make some minor adjustment i make a crank up dynamo that can generate a lot of voltage to the inverter to the battery and last!!! hook up!!!in the six to seven led that make it super work!!!! that so hell great more

PhilKE3FL1 year ago

Hmmm, am I the only one seeing seven LEDs in that flashlight?

bigb09861 year ago
Hi buju357,
please tell me what do you mean 11 windings on the toroid?
there are two windings,A1-A2 and B1-B2. Now tell me which is the 11 windings one of these or both?
buju357 (author)  bigb09861 year ago
I used 11 winding's for both A and B
thanks :-)
If you would like to make it easier for readers to follow up on your Instructable, please include a few more details such as the final schematic, wire gage for your toroid along with your comments about how well you thought that your project worked...
very very nice. I made one a while back only using one 10mm white led and its the brightest little thing. http://www.youtube.com/watch?v=fcTwhqfUkxk
whats the run time on yours?