Joule Thief

[innovation_station]

here are a few pictures of the finished solar light 24 leds useing the bobbin unit ... 

im shipping this unit tommorow

nice n bright

ist

[WilbyInebriated]

If you have any construction info I would greatly appreciate it!  I want to understand this tech to adapt to other things we are all working on.

here is some info on winding tesla primaries, pancake style. i know this isn't bifilar like you want to wind but it might give you some ideas.
http://www.tb3.com/tesla/hugecoil/primary/primary.html
http://www.capturedlightning.org/hot-streamer/exxos/room/mycoil.html

[WilbyInebriated]

thanks jeanna, glad the link helped.

@resonanceman
very small bobbin cores can be used with good success. i have a jt using a bobbin core that is a bit smaller in diameter than a AAA battery and 1/4 the length. i have access to a good camera now so if you want a close up of it, give me a shout.

[jeanna]

I have succeded in finding another way to build a JT of low results...Oh well back to winding the next idea

Ah yes, stprue

Your boneyard must look a lot like mine by now.

I am finding a use for them as plain inductors on the ac side of things. Maybe you will find a good use for yours too!

jeanna

[resonanceman]

IST

Your bobbin in  the bottom picture may be  the  idea I have been looking for .

I need  a way to make  my  " system " smaller .
I have a few inductors around wound on a bobbin like  in your picture . 

I  think  I will  try winding   a bifilar  primary around the outside of them


gary

Not  bad  for a first  try

With  the  bobbin I used  it took  11 winds  ( bifiler )  before   the  JT LED  lit up .
I  added 2 more wraps  just to make sure .
I used   a twisted  pair from a cat5 cable

I then  wrapped  150  turns of  green Radio Shack wire   around it .

that  gave me 51V   
I had a  flyback /feedback  network set up for a LM ..... I connected it  and  got  57 V  across  the  LED array ......about half  of what   I was getting  with the  LM ......but the  frequency must be higher  or something  because the light is brighter .

I guess I am  going to have to find some more of  these   bobbins



I did  try wrapping  a  primary  around the coil ...... not  enough wraps to make  any real voltage .......but to many wraps  to be useful as  part of the  prinary .
I took  off the  original  wire and   just used the core


gary