Joule Thief

[stprue]

@Jeanna

It seems like to me that the only way to not double overlap you need to skip a turn each time!  Is this true?  I don't get the double overlap this way!

[jeanna]

Hi stprue,
The pic is nice and clear and close enough. (HOW are you doing that?)

I am not too sure about your question, because what I see there is that some are crossed on the outside but others are not. You can force them to cross in the inside, by forcing the outside to NOT be crossed and to stay in between the same 2 wires until after you have  turned and go inside again.

Now, when the wire emerges from inside, you move it over inbetween the next wires . This way the cross is forced to be on the inside.

So,
I keep my thumb on the wire after it has emerged from the inside and carefully keep it from straying by pulling it tight and keeping it tight and when it goes over the last curve on the outside I move my thumb to hold the wire in this place.
Then, I feed it through and when it comes out again I check to make it go between the next 2 wires and hold it with my thumb again.

I can't do any of this in a hurry.
I put on some soothing music stick a piece of chocolate in my mouth and start.
It usually takes about an hour or one cd.

I am not sure if this was your question. If not, please ask again.

jeanna

[Mk1]

@stprue

Try doing the same thing with the cross on the inside of the toroid , that way the outside of the toroid will have all parallel windings and leaving you more room for turns . also look at my post on page 478.

@jeanna

The only thing that can vibrate a core is it own resonant freq , if its not right is will not vibrate even at very high hz , but with those freq other core could start to look interesting .

Also when you test the coils with a led , is this with the led connected to bridge output of just to the pickup coil . It make a big difference .

I guess it is clear the the base coil is under the influence of the collector coil , i started to have issues with that an i am looking for solutions .


@xee
Great work , lighting the tube ! I wonder what would happen if all 4 legs of the tube where connected , maybe 2 pickup coil ? humm
I find that its not only a voltage issue but also freq with those tubes

@all

You  can design and type of winding you like , some design on some toroid work but not on other some will have dead spots but you will not know if you don't check, there so much fun to have winding those toroid , don't be afraid to improve the design , but try to stick the the same toroid or same type , winding more then once is just more fun .

Dead spot can be tested , really quickly you need one wire and a diode bridge .

Take the wire make a single turn coil around the toroid .

Connect the coil to the bridge using the ac legs , connect volt meter to dc side of the bridge.

Turns the jt circuit on , test around the toroid for spots with week or no voltage , compare to high peeks , with those info it should be clear if the design is appropriate for the toroid .

[stprue]

Ok so it's like an inside core diameter crossover and then on the outside you thread under loops previously made?  I do get the described look with one crossover in the front.  Is this right?

Sorry for all the large pics I just want to make sure I'm doing this right

[jeanna]

Yes, I think that is all right.
You make the change of 'slot' between wires before it turns the corner to even come out from the bottom. That keeps all of it inside.
I really don't know if it matters where it is, but you will run out of room inside if the cross to the next slot happens not on the inside.

jeanna