Joule Thief

[Mk1]

@ist

I don't know .

@all

I need suggestion on how to recover the bemf on the jt , i made on with 50 turn each on the jt side ...

We need to learn if the secondary will react favorably to it or not.

[Mk1]

@stprue

The test i have done showed that the coil inside the toroid worked better , it seems to be trapped there , and its not pushed out .

[xee2]

I wound that big toroid but i went 420 turns . I did something wrong because i only get like 2 volts  ? Maybe 420 is way too many and snuffed out the resonance ?

Try reversing the pickup coil leads when you make your voltage measurements. There is only high voltage one way. You are using a diode and cap and DC setting aren't you?

[powercat]

welcome back Bill and Gadget  cat

[gravityblock]

Could K be flux density?

jeanna

This was asked quite a few posts back, so it may have already been answered.  I'm trying to play catch up by going through all the posts.  This question is very important in my opinion.

k is the spatial wavenumber, (i.e., the spatial frequency)

A choice of +k gives an internal magnetic field and -k gives an external magnetic field.

It has more to do with the direction of magnetization within a ferromagnetic material (How the magnetic flux is being distributed).

Please refer to this article on wiki for more information on "k".  http://en.wikipedia.org/wiki/Halbach_array  Pay careful attention to the Halbach Cylinder where the concept could play a role here.

We may be able to exploit this to our benefit.  Maybe it's already following it to a certain degree.

Hope this helps,

GB

Edit:  Here's a video on how the flux is distributed in a simple circular halbach array, http://www.youtube.com/watch?v=qv-9IAj_YnI