Joule Thief

[gadgetmall]

now there got to be an easer way to get all those attachments .. Most boards have a little paperclip at the home page with the forum thread title to grab all the attachments otherwise if someone has the time (a couple weeks) they can grab all that stuff and zip it up  With all the information on here we could make a DVD .

[Pirate88179]

@ MK1:

I was just rereading about induction coils in one of my electronics books today and it spoke specifically about ferrite toroids. (although not wound bifilar like we are doing)  It said that as long as the magnetic field of one coil breaks into the magnetic field of another coil, or coils, there is no connection needed. (Induction)  They said there were no losses in using them in this manner.  The book had a picture (drawing) of the magnetic fields around the toroid and they extended quite far from the coil itself.  I will have to go back and see what you did but I was thinking that we could put a secondary on a separate coil, or coils, and position them coil close enough to the primary coil for induction to take place by overlapping the fields.  Do you think this would work?  Or, is this basically what you already did?  If this works as I described then we could have several secondary toroids with different numbers of windings on them.  This would make it easier for testing purposes I believe.

I wound a new JT using one of my new thick 1" toroids and it puts out great!  Instead of the 1k resistor I found a potentiometer and used that instead.  I can turn the pot and the light gets brighter and brighter and then...it dims a bit.  so, I just back off a little to obtain the brightest possible light I can get.  One thing I noticed is that when I go too far and the light begins to dim, something in the circuit emits a very high freq. sound just like the Fuji circuit does.  I don't know what this means.  When I back off and the light brightens, the sound is barley audible. I have also made a circuit with 3 supercaps on my breadboard that run the leds for some time.  I want to make a video showing that, all I have to do is touch my battery + to the breadboard power input for less than a second, and the leds light up for about a minute.  when I use 2 leds, they just go out when they run out of power.  When I use one led, it begins to flash on and off like Jeanna's was doing and will do this for sometime even though I only charged the caps for less than 1 second.  I am trying to think of a way to demonstrate this in a video and then I will make one.

@ ArticKnight:

I did not see any posts from you that were harsh in any way.  Don't worry about it and keep experimenting and posting.  You device sounds fascinating.  I can't wait to see it.

@ Jim:

Have you had a chance to play with your large toroid yet?  I'll bet that baby can hold some wire.  When I get some more money in, I would like to get one as well.  Might be a little while though.

Bill

[Artic_Knight]

@Artic_Knight

It is just a regular jt but the coil are limited to 7 turns (on some toroid 4 is enough)and the rest of the toroid is covered with 2 additional coil of 26 turns , They both give me 67 volts .

All of this has been covered in the tread. check some pages before the p 125.

Edit :Now ,you can see! welcome to the tread mate.

Mark

so let me understand this you have the primary joule thief running with an additional 2 coils? and your tapping the additional 2 coils which happen to be higher turns to light these lights? thats how it was done?

[Mk1]

@pirate

There are many factors  battery voltage and the resistor will change the freq , Each different core as a saturation freq , at that point the toroid drops in effectiveness , But turning the pot you go form bad to good and good to bad. Get the voltage as high as you can. The bigger the toroid the slower the saturation freq. At high freq you get more pulse per second giving more output.Smaller toroid in theory should give more output
Since it can handle faster switching without full saturation.

You can put as many pickup coil as you want , they do not need to be close to the jt coils.The core keep most of the magnetic in.

Mark

[Mk1]

so let me understand this you have the primary joule thief running with an additional 2 coils? and your tapping the additional 2 coils which happen to be higher turns to light these lights? thats how it was done?

Yes Sir , that simple! No wonder most don't get it , its to simple.

Edit : btw , my last one gives me over 200 v .

Also any jt has the power to light over 100 leds easy.