Okay, thanks. I'll wait for gadget to confirm the circuit and see if the "1 watt" LED is optional. I'm not here to chop apart his circuit or judge it, or make any assumptions, but just draw it the correct way, and then build it.

Paul

Hi paul . Its not an option if your replicating My circuit It causes an effect of reducing the current input as  Jeanna and mk1 and ist and well every one else will tell you  . If you use the EXACT parts you will get THE EXACT results !! If you dont then you probably won't .
Thanks for the interest .

GADGET

Ive been getting reasonable results off of two identical axial lead inductors placed parallel (and reversed ) to one another.

..8.5 volts on one and 35 volts on another setup... unfortunately this doesn't produce the spectacle that other joule thief circuits do, but it's worth noting that the configuration is similar to my 2 coil Helmholtz setup.  I"ve tried placing a tertiary, but i'm limited by proximity, size factors make the circuit cumbersome to put on a breadboard..

....

Hi jadaro,

I think there are 2 things missing from making separate inductors like this.

1- as you noted, you cannot get them close enough to each other to make a proper secondary and

2- the toroid shape allows the magnetic flux to stay within the inductors. It switches back and forth depending on lots of things-basically tuning, and because the magnetic flux is not dissipating or radiating (much) it continues to oscillate with little to no work added.
In these circuits with secondaries, the only work needed to be added is just what it takes to run a transistor.
And that is less if the transistor is off much of the time as it is when the base resistor is a high ohmic value.

These are just some ideas based on my experiments and conclusions I have made based on what I have tried.

thank you,

jeanna

@paul

You should listen , to what we are saying , since it seems impossible , maybe make a regular basic joule thief ,first, and if you really can't go 5 pages , what are we to do post the schematic every page ?

The only hard thing about it seems to get you to get it.

Make one !

Hard ? can't go 5 pages back , lol ...

Okay Gadget,
 
 Attacked is the latest. Any corrections? I want to get this exact! As you say, everything must be exact.     I'm sure there are more corrections for my circuit drawing.
 
 Thanks,
 Paul
 

Technically, the two connected windings are not a center-tapped winding. They are wound bifilar, and connected in series-adding. They are in effect two primaries connected in series, and the output winding is a secondary driving the LED.

A center-tapped winding or transformer is one continuous winding that has a tap somewhere along its travel. This is quite different than what we have here on the JT.

I think you would find that the circuit would work equally well if the three windings were put on separately, and the two which are connected could be done so as a true center-tap. The coupling due to the core is quite good I imagine, so it probably makes little difference how the windings are put on.

.99

really i is center tapped . another way to wind this is take one wire wind 6 turns pull a loop then wind 5 more same thing . when you wind two wires two wires together you have two that you started with and two at the end . you have to ohm out one of the first two wires and connect it to the opposite wire on the end side . I hope this makes since . and again maybe not . I might be an alien and cant communicate with people 

gadget

@ Paul:

Gee, you want everyone to drop everything and help you and yet you can't take the time to read back more than 5 pages?  What's up with that?

Also, just to let you know, I noticed how you were badgering Slayer007 about his drawings on Dr. Stiffler's topic and demanding that he post them your way.  Well sir, we do not put up with that over here.  These are a great bunch of hard working, helpful folks here who have tried to help you. We will not put up with any one that comes into these topics and makes demands and yet can't take the time to read what is already out there.

Just letting you know for the future.

Bill

I don't know about "demanding" that slayer007 post the circuit details, but his circuit was incomplete. This is open source forum, right?

Paul

The reason it is centertapped is because the place where they are joined  is connected to the positive of the battery.
If you connect the other (free) ends to the battery terminals it would be in series.

another way to say it is:
the direction of the turns is opposite on this and that is what is making it oscillate.
You can try all day long but if you make them this way it will oscillate, and if you don't it won't.

thank you,

jeanna

Nice! I just saw that in spice. If the windings is wrong, it will not oscillate. When I reversed the winding as you say, it is now oscillating! 

Thanks for the help,
Paul