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Author Topic: Joule Thief 101  (Read 926732 times)

Montec

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Re: Joule Thief 101
« Reply #90 on: March 13, 2011, 09:29:25 PM »
Hello all
Crucial  knowledge that I have gleaned from the internet over the past few years regarding magnetic fields and inductors is:
1: Usable energy from magnetic fields in inductors is stored in the gaps between magnetic materials. ie magnetic materials do not store energy they just transfer energy.
So the best types of coil cores for the Joule Thief would have gaps incorporated in them. ie gaped laminate cores or powdered metal cores (the gap is between the metal particles) The coils should to be wound over the gaps for the best result or equally spaced on the powdered metal cores.

Non-gaped laminate and ferrite cores make excellent transformers but poor energy storage inductors.   

:)

ltseung888

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Re: Joule Thief 101
« Reply #91 on: February 04, 2012, 04:03:16 AM »
See the following
 
http://www.overunityresearch.com/index.php?topic=1171.msg20464#msg20464
 
for the secret behind the Joule Thief and FLEET.
 
The attached diagram is the Output over Input Power Comparison.  Enjoy

resonanceman

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Re: Joule Thief 101
« Reply #92 on: February 04, 2012, 05:00:34 AM »
See the following
 
http://www.overunityresearch.com/index.php?topic=1171.msg20464#msg20464
 
for the secret behind the Joule Thief and FLEET.
 
The attached diagram is the Output over Input Power Comparison.  Enjoy

I think you have something here.
I have been thinking of something for a while but I dont have the ability to really test it.

Most of Teslas later work involved spark gaps.....these insured a high rate of change but would also require relatively high voltage.

From what I understand the Howard Johnson motor used around 2000V

I understand the Gray conversion tube used 3000V

A joule thief creates a pulse with very high rate of change.
What would happen if someone amplified the output of a joule thief?
What would happen if someone used a joule thief to charge a capacitor to lets say 1000V ......then pulsed that with a signal from a second joule thief.
Any guesses what the BEMF pulses from a 1000V joule thief would be?

It seems to me that if you fed an 1000V joule thief type pulse into the right sized transformer you would  have a delay line generator.

Nothing really new here.......but in my opinion using joule thiefs for the high voltage supply and for the pulse supply would make the circuit smaller and cheaper.

gary

resonanceman

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Re: Joule Thief 101
« Reply #93 on: February 04, 2012, 06:10:01 AM »
I think you have something here.
I have been thinking of something for a while but I dont have the ability to really test it.

Most of Teslas later work involved spark gaps.....these insured a high rate of change but would also require relatively high voltage.

From what I understand the Howard Johnson motor used around 2000V

I understand the Gray conversion tube used 3000V

A joule thief creates a pulse with very high rate of change.
What would happen if someone amplified the output of a joule thief?
What would happen if someone used a joule thief to charge a capacitor to lets say 1000V ......then pulsed that with a signal from a second joule thief.
Any guesses what the BEMF pulses from a 1000V joule thief would be?

It seems to me that if you fed an 1000V joule thief type pulse into the right sized transformer you would  have a delay line generator.

Nothing really new here.......but in my opinion using joule thiefs for the high voltage supply and for the pulse supply would make the circuit smaller and cheaper.

gary

I have played with this idea a little.
I have a few suggestions for anyone that wants to play with the idea
I suggest using a bridge as a voltage clipper on the output of the pulse supply JT
The output of that bridge would go back to source......so your source battery should be at the voltage you want to have feeding the gate of your MOSFET or IGBT
I burnt up quite a few IGBTs trying to tailor the joule thief to the right output to feed the IGBT before I started using a bridge as a clipper.


I fed the output of the pulse JT into a bridge.....both posative and negative legs of the bridge go to the gate, the negative through a resistor.
This resistor will vary depending on other circuit components.
10M might be a good place to start.
The negative connection  is to keep an IGBT turned fully off......but should allow faster switching with MOSFETs.


I have not yet ramped up to high voltages........but I have been playing.

I dont have a scope.....my way of testing to make sure I have pulses rather than a simple DC signal  is to run  it through a transformer.
an output on the transformer secondary means I have a pulse.

gary

ltseung888

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Re: Joule Thief 101
« Reply #94 on: February 04, 2012, 04:06:54 PM »
I think you have something here.
I have been thinking of something for a while but I dont have the ability to really test it.

Most of Teslas later work involved spark gaps.....these insured a high rate of change but would also require relatively high voltage.

From what I understand the Howard Johnson motor used around 2000V

I understand the Gray conversion tube used 3000V

A joule thief creates a pulse with very high rate of change.
What would happen if someone amplified the output of a joule thief?
What would happen if someone used a joule thief to charge a capacitor to lets say 1000V ......then pulsed that with a signal from a second joule thief.
Any guesses what the BEMF pulses from a 1000V joule thief would be?

It seems to me that if you fed an 1000V joule thief type pulse into the right sized transformer you would  have a delay line generator.

Nothing really new here.......but in my opinion using joule thiefs for the high voltage supply and for the pulse supply would make the circuit smaller and cheaper.

gary

Dear Gary,
 
The Taiwan LED Manufacturer is improving their LED Hat product shown to use one single battery and prolong the life of that battery many times.
 
That should not come as a surprise to you or the many long time Joule Thief Researchers.  The surprise is that they use Two Atten Oscilloscopes to hunt for the “right configuration”.  That put them in very solid scientific footing.
 
There is a very strong possibility of significant Government funding in the near future.  There is talk of giving every US Law Maker and/or every United Nation Representative in New York a “forever lasting” LED Hat. 
 
Overunity Research will get a boost???  Keep up your excellent work.  Money will seek the experts.  I strongly suggest that you get at least one Oscilloscope with csv file capability or work with someone with such a device.
 
Divine wine is for all.

resonanceman

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Re: Joule Thief 101
« Reply #95 on: February 05, 2012, 01:20:08 AM »

Dear Gary,
 
The Taiwan LED Manufacturer is improving their LED Hat product shown to use one single battery and prolong the life of that battery many times.
 
That should not come as a surprise to you or the many long time Joule Thief Researchers.  The surprise is that they use Two Atten Oscilloscopes to hunt for the “right configuration”.  That put them in very solid scientific footing.
 
There is a very strong possibility of significant Government funding in the near future.  There is talk of giving every US Law Maker and/or every United Nation Representative in New York a “forever lasting” LED Hat. 
 
Overunity Research will get a boost???  Keep up your excellent work.  Money will seek the experts.  I strongly suggest that you get at least one Oscilloscope with csv file capability or work with someone with such a device.
 
Divine wine is for all.

Itseung

I am glad to see that someone from the corporate world is using JT type technology

As far as giving hats at the lawmakers to impress them ......what do you think will impress them more a hat with LEDs that last very a long time or a big fat check from an energy related PAC.
Our elected officials vote according to their PACs all the time......so the checks just keep rolling in.

I will believe the govenment will take free energy serious only when we have a multi billion dollar free energy PAC to buy their loyalty

I do believe that there is free energy in our future........but it will be in spite of our governments not because of them

`````````````````````
I have been looking into getting an Ocilloscope from time to time.
The little cheap ones are getting better......but for the things I would want to do I would need one that was fast and could handle high voltage...




gary

d3x0r

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Re: Joule Thief 101
« Reply #96 on: February 05, 2012, 04:59:05 PM »
I thought I might contribute a 'what not to do' maybe save someone in 101 from having a lot of problems.
I was testing my joule theives with an adjustable DC power supply, something like 0-30V and/or 0-3A...
My first one, I wound on about 8 turns of iron fence wire, ended up using about 24 inches of phone patch wire around that, and before I remembered that this thing was supposed to run off of very small voltage (dead AA batteries < 1.5V) I fed this with like 12V+ and ended up popping a couple transistors (they now read open in all directions :) ) .  I did get this to work, but it requires like 0.06A 0.6V to minimally light an LED.  I tried all sorts of modifications, smaller turns (1inch inner diameter), more wire at the smallest, so my first was 1x, second 2x and third 4x.  The last worked sort of the best, but then when I went back to my first, it had a better spike earlier on.  (yes this is all subjective, maybe i'll try and edit this later to include some pictures.  I finally stumbled on a ferrite toroid.  Wound aobut 2/3 the length of the wire I had been using on it, and wow did that make a difference.  Could light an LED with 0.00A and 0.3V :)  Limitations of equipment... but I could like 4 with like 0.02A and 0.6V...
 I have a couple 6 meter coils that I put on a iron axel of some sort, and connected the coils in opposing direction just like a JT.... these actually worked pretty well, but required a bit of current to get a good flux exchange.
I did learn intersting things like the more current you put into an Iron toroid, the higher the frequency goes, until a certain point.  With the ferrite, the less current I put in the higher the frequency, so at like ground 0 it's already way ahead of the frequency of the Iron... I think I could turn it down just below it turning off that the frequency would go back up as if on the other side of the low current side of lower frequency.  Defintely bying some real ferrites :)
Oh the other thing I was trying was seeing what effect magnets had on the core, with Iron there was 0 perceptable effect, on the ferrite, alinging the magnet N/S along the circumferance of the torus was the best performane. (was on a spot the torus that had no windings).  Putting the magnet in various direction in the center of the torus was basically just asking the cirtuit to stop working altogether.  Figured if I had a magnet mounted on the side, good way to adjust the frequency would be to just turn the magnet from aligned along the ring to vertical to the ring (which is basically the same frequency as not having the magnet).  Was playing with variuos configurations with multiple magnets but didn't get anything very useful. 
 
So what to conclude: don't use stranded iron cores if you want a small, elegant joule theif.  You need higher current to get the same magnetic flux induction, or many more windings.
 
Also in all my coils I couldn't use a resistor bigger than 33 ohms connecting the control coil to the base... actually I had to short it with a 2Ohm resistor to get it to work, finally removed the resistor altogether.  The base never went to a high enough voltage to trigger with like any resistance there.  (was using a MPSA06, well was using 2n2222's but blew up 2 of them trying to see if more voltage would make it work; [right if all else fails, use a bigger hammer?])  Was still afriad of putting more than 0.5A through it, but tested up to 0.89 a few times (even at the 1.5V limit on the other side)
 
A person early on in this thread said they had JT's wound on air, copper, everything else and that it was impossible to make one that didn't work; I really beg to differ, I had a horribly hard time making my stranded iron cores work.   And a magnet sticks to it better than to the ferrite core. 
 
Use ferrite!

ltseung888

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Re: Joule Thief 101
« Reply #97 on: February 05, 2012, 06:50:56 PM »
Itseung

I am glad to see that someone from the corporate world is using JT type technology


I do believe that there is free energy in our future........but it will be in spite of our governments not because of them

`````````````````````


gary

I was discussing this with an India Engineer.  The discussion focused on the arrogance of the average American who had been spoiled by their past successes.  The attitude is - “how could an old retiree with limited resources from a backward Country solved the Energy Crisis”?
 
He came to watch the demonstration with an American.  He did much more reading and tried the Joule Thief building but his American friend laughed at him.
 
The likely result is that someone from “a backward country” will produce an overunity product and then US will play the catch-up.  It will not take too long.  Some predicted the end of the world would come on December 20, 2012.  It may be the end of the old world that relied on fossil fuel.
 
The scientific evidence is here and can be repeated even in the most backward countries.  Will integrity or arrogance win???

resonanceman

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Re: Joule Thief 101
« Reply #98 on: February 06, 2012, 12:09:34 AM »

 
The likely result is that someone from “a backward country” will produce an overunity product and then US will play the catch-up.  It will not take too long.  Some predicted the end of the world would come on December 20, 2012.  It may be the end of the old world that relied on fossil fuel.
 
The scientific evidence is here and can be repeated even in the most backward countries.  Will integrity or arrogance win???

Will integrety or arrogance win?
easy question........arrogance has won every time so far.

Lets say your backward country inventer came up with a great little free energy machine.
At least one of the arrogant people with more money than brains would offer them a boat load of money for it......if the inventer takes the money his invention is never seen again.......if he does not take the money  they resort to charactor assanation and threats.

There is nothing honorable or just about the people that are controling these situations.
If your inventor tries to make money from his free energy machine he will loose the battle........The cards are stacked against the free energy inventer ........and the dealer knows exactly what cards are on the table.

gary

resonanceman

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Re: Joule Thief 101
« Reply #99 on: February 06, 2012, 12:32:18 AM »

A person early on in this thread said they had JT's wound on air, copper, everything else and that it was impossible to make one that didn't work; I really beg to differ, I had a horribly hard time making my stranded iron cores work.   And a magnet sticks to it better than to the ferrite core. 
 
Use ferrite!

I do not know who said that.......it is true in part.
Air core JTs can work.....but I had problems making big air core JTs.
I see no benifit to a copper core.
Bismuth did not work

Like you I had trouble with Iron core JTs.......whether it was powered a powered iron toroid plain iron or black iron oxide.....I am sure they can be made to work with enough power ........but why bother.

In support of anything working........if you use a base resistor and put a fairly good sized capacitor across the resistor to make a tank circuit even 10 or more ft of twisted pair will work as a JT......just connect the end to the beginning of the other wire and fire it up.





resonanceman

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Re: Joule Thief 101
« Reply #100 on: February 06, 2012, 12:56:11 AM »
Just thought I would update my information on what I called candy cane coils
I called them candy cane coils because on my first ones the windings spiraled around the stack of toroids like the stripes on a candy cane.

Now I would call them modular coils.
If you have a project calling for a large ferrite toroid but you only have smaller toroids you can split the windings of both the primary and secondary over a number of smaller toroids.

The total number of primary turns VS the total number of secondary turns seems to work out almost as if it was one large toroid.

It can also work to put your primary on 1 toroid and leave a long wire to connect  with the collector........this wire can then go through quite a few toroids......any windings on these toroids become secondarys...... I suggest going for fairly high voltage in the primary if you try this.

If you dont need alot of power from your secondarys just passing the wire going to the collector through the center of the toroids may be enough.....wrapping then around the toroids increases the power but usually lowers the voltage.


gadgetmall

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Re: Joule Thief 101
« Reply #101 on: September 08, 2012, 07:11:40 PM »
Here is a video tutorial from makemagazine for a Solar Joule thief bracelet http://www.youtube.com/watch?v=ghB2irHIN8I&feature=related

Pirate88179

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Re: Joule Thief 101
« Reply #102 on: September 08, 2012, 07:26:40 PM »
Gadget:

Wow, the little JT circuit is really getting around everywhere now.  That is a cool application.

Bill

dennisk

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Re: Joule Thief 101
« Reply #103 on: August 16, 2013, 07:34:23 PM »
Hi sierraloewe,
After you have made your first jt and it works, then it is time to delve into those questions.

Follow the makezine or evilmadscientist youtube as closely as you can.

The gauge I use for the primary bifilar is 24awg. I got this from a telephone extension cord.
The length you will need to make this first one will be about 14 inches of each wire.
 This depends on the fatness and diameter of your toroid, so this is just a guess. (I use a small one and it takes 11 inches of each wire and is very generous.)

After you have made a plain joule thief make a second one exactly the same way. Put the led into the led spot but do not solder it.
Remove the led when you prove that the circuit works.
Now, wind a secondary.
The choice of gauge for the secondary is up to you.
The thinner wire will make higher voltage, but the problem with really thin wire (like 30awg from radio shack) is the insulation is easily scratched. If it gets scratched you will have little to no voltage from your output.
One more thing about the secondary.
The side of the primary that connects to the collector coil is the part that is being "transformed" so, if you have 10 turns on the collector side (you do now if you are following the makezine video) Then double that will be 20. So, make your first secondary with 20 turns.
This will give you a starting point for reference voltages.

Now, you have 2 very useful circuits.
1-the plain jt is the best way to get the last bit of joules out of the battery. It makes a terrific emergency light.
2- The battery needs to be a little higher for the secondary to work. There are exceptions to this, but most of the ones that use a secondary run down after the battery is at about 1.1v.
So, you use the jt with secondary then when it is no longer bright you switch that battery to the plain jt.
This does not apply to a rechargeable battery.
Do not use a rechargeable in a plain jt, because it is not good for batteries to be so thoroughly drained.
 (I could never figure out why but it seems to be so.)

After you have made these 2 you can start experimenting.

I have found that it is very important to make the wires wound snugly onto the toroid.
It is possible to have a good one that is loosely wound but if you want high voltage... get it tight around and try to have as many winds as you can actually in contact with the ferrite.

(I believe there is a difference in opinion about loosely wound together, but this is not about wound together, this is about being tightly wound on the toroid itself.)

That toroid is a powerful source of "something" that makes high volts.

I hope this helps.

jeanna
I noticed you said not to use deep cycle batteries that have been completely discharged.  I don't know if this is off topic but have you tried recharging them with the Bedini school girl charger?  Just curious.

sm0ky2

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Re: Joule Thief 101
« Reply #104 on: February 05, 2016, 11:12:03 PM »
Hi all,

after months of lengthy conversation with a couple of my guitar-builders
I think I can explain the resonant operation of a joule thief circuit, in a manner which the technicians and builders can more easily understand.
(and replicate)

the biggest problem I have encountered when discussion self-resonant JT operation, is other builders cannot seem to get them to operate
in a resonance mode.

Several heated discussions, have led to the understanding of SRF with respect to the LRC portion of the circuit.
However, the transistor function seems to cause problems for many.
I have tried to explain the process of "tuning" the base resistor, while observing scope image of the primary transformer winding.

What I kept getting as a response, was asymmetric scope images of the transistor switching
(I assumed they were measuring across the LED (diode).....)

These scope images were sent to me and/or posted in multiple JT threads, displaying a sharp increase in voltage during the "switching on" time.
And an elongated (delayed) voltage decrease during the "switching off" time.

Part of this I have found to be a function of certain LEDs. They store energy across the diode (capacitance), which dissipates over time after the LED is switched off. meaning there is still current flowing through the diode after the transistor is off, and the production of "light". This can result in a misleading scope image. I state now - the (indicator) LED is not an essential part of the Joule Thief Circuit.
It is simply an indicator to let you know the JT is in operation.

Remove the LED, and the Joule Thief will continue to operate.
Now the scope image, across the coil, does not include the diode bias discharge.

Still I was receiving similar responses - they could not get their JT to run in a resonance mode.

At some point I gave up trying to explain this to people, because they just wanted to argue rather than try to understand what I was explaining.
Similar scopeshots of an asymmetric transistor switching were presented, and this was a sort of 'road block' to the communication process.

Anyways, my recent discussions with JT builders has given me a new perspective (and perhaps new terminology) that others may understand.

there is a voltage bias (different for each transistor) which sets the switching function into what is called in the transistor world

"linear mode" This term is derived from power graphs, in which the function is linear.
With the voltage biased within this range, an A/C waveform translates perfectly across the transistor.
People in the radio world already know this, because such is necessary to use a transistor for analog frequency response.
But I have found, that digital techs often know nothing about this mode of operation.

Each transistor can switch in a purely sinusoidal fashion when the base resistor is biased to within the voltage range of this "linear mode" of operation.
Within this linear mode, changes in the bias voltage results in a range of operating frequencies.
The SRF of the circuit should be designed to within these parameters.
Most standard JT designs are capable of this.

It is simply a matter of adjusting the base resistor to match the self-resonant frequency rest of the LRC circuit.

This is evident in the scope shot across the coil, As the waveform will become perfectly symmetrical.

When this occurs, the JT circuit will output the highest possible voltage and current for the input.
And as such, this is the most efficient way to use the JT circuit.

This is the difference between a Joule Thief powering a light for a few days,

vs JT's that have been running now for years.

all off what we would consider to be a "mostly dead battery".
meaning, one that has been drained below the operation conditions of most equipment.

So, when starting with two similarly drained batteries, why such a great discrepancy in run times?

In non-resonant operation, a JT circuit wastes a lot of energy, bucking against the natural frequency response of the coil.
This generates heat and EMF radiation. Because the field collapse and the charging function have a gap in time. and/or are an asymmetrical function, due to unsynchronized transistor on/off times.

When the transistor is in linear mode of operation, the sine-wave from the coil (through the base resistor), draws current from the battery, corresponding to the waveform. If you take a current scope shot of the signal in this mode of operation, you find the current also follows the same sinusoidal waveform.
slightly advanced ahead of the voltage. (~90-degrees)

I hope this helps, I haven't quite given up trying to deliver this message... it just gets frustrating with the language barrier, when it comes to technical terminology, differences between engineers and techs, etc...
People either have a hard time understanding what im trying to say, or they take a term in another context than the one in which I was trying to deliver it...

anyways, apparently the proper name for this mode of transistor operation is called "linear mode" in the technician world.
It is listed in the technical specs of the transistor - so you can get a feel for the biased voltage range of the base resistor.
The number of turns in the coil should correspond to this range of voltages, and by proxy, affects the SRF of the particular circuit.