Joule Thief

[resonanceman]

Gary,
ARE you getting more power out when you start with more volts?
In my jt experiments, if I try a 3v battery instead of a 1.2v which is a rare curiosity experiment, I do not get higher voltage out. I get higher frequency, but even that is not much higher.

It seems to me there are 2 special things going on.

1- the basic joule thief toroid with the transistor cutting on and off, then

2- the secondary which derives its output from the toroid and other than that,  has little if anything to do with the energy going into the basic jt.
Its power is derived from the inductance it has because of the number of its windings and the oscillations being caused by the EMF of the toroid.

They are together on the same toroid, but are only joined by the magnetic fluctuations. So, a higher input won't make a much higher output unless it changes the rate of oscillations. And, although I have  seen it do that with increased frequency, I have not seen much increase in output..
The number of turns and turns ratio to the primary Collector turns is what will increase the secondary in my experience.

Are you also seeing this?

jeanna

Jeanna

I have noticed that .

IF ....  you are using  a normal  toroid JT ........and   your core  is  reaching saturation  with a AA battery  I would  not  expect   to  get much more out of it  with higher  voltage .

A  JT  would  have to  be tuned  for  running  at the  higher  voltage .

A  JT  made  with  a different  kind of  coil  like a MOT  or  flyback transformer  would be  much  more likely  to  produce higher power  with higher  voltage .

gary

[jeanna]

@ jeanna

Inductance of coil increases as square of turns. Thus doubling turns produces four time inductance.

Equations here: http://www.phys.uri.edu/~gerhard/PHY204/tsl267.pdf

chart here: http://www.gqrp.com/toroid_inductance_chart.pdf

Your measurements seem to confirm theory.

Thanks for those links, xee2.
I am not sure how what I see is confirming the N² part.

I just wound 18 turns on the same toroid with a wire and tested each turn for inductance. So, this puzzles me.
if I look at the difference of inductance from 4 T to 16T it does not double at all. Nor does it square.

N=2, L=.012mH
N=4, L=.041mH
N=16, L=.62mH

What am I not understanding here? (thank goodness for calculators!)
If I understand the formula ...  ,
L will change linearly as the square of the number of turns.
So a straight line should be formed by plotting the inductance values of 2T, 4T, 16T. Is that what this is saying?

I just plotted it and I see not a straight line but a gentle curve that steepens as I add turns.

I will appreciate the answer to this. I think I can understand it if you keep it simple, which I believe you can.

thank you,

jeanna

[xee2]

@ jeanna

I am not sure how what I see is confirming the N² part.

N1=2 turns, L=.012mH
N2=4 turns, L=.041mH

N2 turns = 2  x N1 turns
2 squared is 4
4 x 0.012mH = 0.048mH
You got 0.041 (fairly close, there was probably some measurement error)


N3=16 turns = 8 X N1 turns
8 squared = 64
64 X 0.021 = 0.768
You got 0.62  (again close, your mH value for N1 is probably a bit high)


The increase in inductance is equal to the square of the increase in turns.
If you increase the turns by 2 you will increase the inductance by 4.

note....... 4 = 2 squared

[Mk1]

you can ask me every thing ( inn french ) in this thread

http://www.overunity.com/index.php?topic=4744.msg98997#msg98997

a lot of people tried to replicate the D'HOKER device
but no OU !!

this magazine is a very bad scentific magazine , no proof

Tell me in the replication where did they get iron isotope 56 , or where could get i get some ...

[xee2]

@ Mk1

Google gives this:

Iron-56 is the most common isotope of iron. About 91.754% of all iron is iron-56.