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Author Topic: Possible breakthrough with the JouleThief (JT) circuit  (Read 80654 times)
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@GibbsHelmholtz
Quote
I've seen you emphasized the important of how an inductor works for a while.  I'm still much curious on how it works.  You must have put a lot of thoughts into it.  I'd like to know your thinking.  This is how I think it works ( not much of  a few paragraphs... probably why I always get bad grades on essays   ).  

We put x amount of energy into an inductor call it 1/2 Li^2 .  On discharge, we gain 1/2 Li^2.  

I think fundamentally your equations are incomplete, for one we would have to assume the inductor can have no influence nor be influenced by anything external to it, that is according to standard  theory the entire universe external to the inductor is irrelevant-- Does this sound logical?. You see it is not the fact that some do not understand how an inductance works it is the fact that some have ignored everything external to it. One would think the fact that we can simply add a small capacitance to the inductance and recieve radio signals would have clued many in or the fact that we can always hear static noise from such a circuit as well, where did this "static" come from?. According to standard theory an inductance and capacitance should do nothing and be lifeless but this is not the case which is odd don't you think?
Regards
AC


---------------------------
Comprehend and Copy Nature... Viktor Schauberger

“The first principle is that you must not fool yourself and you are the easiest person to fool.”― Richard P. Feynman
   
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Lawrence:

If you want to start a thread I am willing.  However, I have already stated that it's almost impossible to make the measurements to confirm or deny that your tuning fork experiment can produce over unity.  You did not reply.  If you can propose a way to make the measurements then we have something to talk about.

About kinetic energy from air molecules:  I saw a diagram from you about that, can you give me the link for that?  At risk of repeating myself, you cannot extract energy from random motion.

Dear MH,

Thank you for taking up the challenge.  I outlined a simple comparison sound energy test on reply 57 on this thread.  That simple comparison may not be exact but can be performed anywhere by any University or Organization with common equipment.

In reply 58, PhysicProf suggested that he may be able to use the echo chamber or the anechoic chamber at his University.

Since PhysicsProf may be the moderator, I propose to use his bench where he has the moderator privilege.  Another task he may be able to perform is to verify every single equation I quote.  Every equation is based on Newtonian Mechanics.  Without a Physics Degree, you may not be familiar with every one of them.  He would be in a position to verify the correctness of every one of them.  He may even be able to quote authoritative academic references.

I shall repost the few important diagrams here.  The spreadsheet references are at my bench under the What is New Thread.  You may want to examine and play with the spreadsheets first before engaging in the scientific debate. 

We can wait for PhysicsProf to set up the threads before the debate.  You may also want to find some friends with strong background in Physics, Mathematics or Mechanical Engineering to participate or support you in the debate.  I may also have one or two academic supporters.

I plan to remove any “dogma” in this proper scientific debate.  Hopefully this single debate will establish the validity of resonance bringing-in surrounding energy.  The same theory applies not only to sound but to electrical LCR resonance.  This single debate will establish the theoretical solidity of many other claimed OU devices.  (e.g. Rosemary, FLEET, Bedini, Adams, Steven Mark, Stan Meyer etc.)

God provided us with almost infinite, pollution free energy surrounding us since creation.  Men did not realize that and polluted the Earth with fossil fuel and nuclear reactors.  With the Divine Revelations, this will change.  Amen.
   

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Tough Love can be good.

We are all born with an intense desire to learn.
We want to learn and to do;  we each have certain
drives and interests which propel us towards a
desired state of self sufficiency - being able to
provide for ourselves and to look after others.

These natural instincts can however, be altered
and even distorted or twisted.  During our formative
years and beyond we are susceptible to "programming"
by authority figures and/or respected superiors.

Consequently, while we are naturally driven to do good,
we can be "programmed" by behavior modification to do
bad; to actually derive intense pleasure from harming
other beings.  Programs have long been in place in most
nations of the world to produce behavior modified minions.

But we are all capable of being "programmed" by our daily
exposure to the media, the movies, the "news," our social
environment.  As we grow and learn and emulate we are
changed for good or for bad.  None of us is exempt.

No, I take no offense at what you, or any others, put forth as
opinions or advice within this forum.  It is very interesting to
observe the exchanges and to take note of the styles of
expression;  the emotional intensity;  the spirit.

Understanding 'coils' and their various properties and capabilities
is evolutionary over a period of time by experimentation.  If we
were unable to experiment until we understood all that there is
to know about 'coils' when could we start?

Our 'beginnings' are most often very short in understanding.  But
as we progress down the road of discovery we learn how things
work.  We adapt, we innovate, we adjust, we share.

For a new twist on 'coils' have a look HERE.

For a peek at the new, "hardened" high temperature MOSFETs
look HERE.



---------------------------
For there is nothing hidden that will not be disclosed, and nothing concealed that will not be known or brought out into the open.
   
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GibbsHelmholtz:

Your answer is too simplistic and there is no gain.  Let's see if Feynman who seems to be deeply involved in research can answer the request for a few paragraphs describing how an inductor discharges.  A good starting point is with my example for the three different resistor values but that's up to him.

Lawrence:

In your diagram with the multiple tuning forks you are claiming that there is extra energy as if that is a fact.  It's not a fact it's your belief.  You haven't made any measurements to back up your claim, and it's almost impossible to make the measurements anyways unless you have very sophisticated equipment.  You don't have the equipment.  Making claims with no solid evidence is very tiring.

With respect to your example of the two balls and the moving piston and the perfectly elastic collisions you are basically claiming conservation of energy.  You show an energy gain when you look at the two balls.  However, you show that the piston has slowed down.  Therefore energy is conserved.  So there is no energy gain and the whole point is moot.

Your numbers are also too simplistic.  It's actually a tricky problem and I am rusty so I am not sure how to get the final solution.  When the B1 ball hits the moving piston the piston slows down and the ball speeds up.  After the collision you have two unknowns, the new speed of the B1 ball and the new speed of the piston.  We learned in school that if you have two unknowns you need two equations to solve for the two unknowns.  You know that momentum has to be conserved and you know that energy has to be conserved.  There are your two equations.  So I believe this is solvable without having to do a mathematical iteration to arrive at the final solution.  It could be an interesting thread in itself.

Anyway, the bottom line is that energy is conserved with your ball-piston example.  You even indicate this.  So what is the point?  There is no excess energy.

MileHigh
   
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I think fundamentally your equations are incomplete, for one we would have to assume the inductor can have no influence nor be influenced by anything external to it, that is according to standard  theory the entire universe external to the inductor is irrelevant-- Does this sound logical?. You see it is not the fact that some do not understand how an inductance works it is the fact that some have ignored everything external to it. One would think the fact that we can simply add a small capacitance to the inductance and recieve radio signals would have clued many in or the fact that we can always hear static noise from such a circuit as well, where did this "static" come from?. According to standard theory an inductance and capacitance should do nothing and be lifeless but this is not the case which is odd don't you think?
Regards
AC

You've set the boundary condition with the universe.  The situation has then changed to an open system.  It does makes sense, but I'm more concern with something even more...fundamental.  Suppose my questions are

1/ How much energy required to charge an inductor to 1/2Li^2.
2/ How much energy can be gain from 1/2Li^2.

Or let me rephrase it in Newtonian equilvalent

1/ How much energy does it takes to cause a mass M to velocity V from relative rest position.
2/ How much energy can we gain from stopping mass M with velocity V to its relative rest.

Simple, don't you think?  ;D
   
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@GibbsHelmholtz
Quote
You've set the boundary condition with the universe.  The situation has then changed to an open system.  It does makes sense, but I'm more concern with something even more...fundamental.  Suppose my questions are

I'm not sure that the situation has changed to an open system simply because a closed system would imply that the inductance has been isolated from all other forms of energy which seems unlikely to say the least.

Quote
1/ How much energy required to charge an inductor to 1/2Li^2.
This question sounds easy but I find it very difficult, :D, first the term "energy" is not defined and can take any known form, second the term "charge" is misleading as the inductor is already charged as neutralized charges which is matter, free electrons having a negative field associated with them and any surface charge, a potential, relative to the environment. We should also consider that we do not "charge" an inductor as it is commonly understood, we produce an imbalance of the distribution of pre-existing charges across an inductor which we call a potential difference or voltage. As such when we move our hand near an inductor we have "charged" it because our body has a positive charge due to our environment and this surface charge induces a charge imbalance across the inductor. However under the extremely limited confines of the popular understanding of "charging" a completely isolated inductor from a completely isolated source, that is a source having a charge density imbalance and this imbalance applied across an inductor, then the energy loss of the source equals the energy gain of the inductor minus any energy which has been transformed into another form, energy is conserved locally.

Quote
2/ How much energy can be gain from 1/2Li^2.
First I would state that we cannot gain energy from an equation, 1/2Li^2, an equation is simply numbers and signs which represent conditions(phenomena) or measures as they usually relate to one another due to interactions. I tend to practice fundamental physics which is a little different, for example Voltage is not something it is a measure of something, it is a measure of the imbalance or differential charge density between two singular points. The charge density is not something it is a measure of something, that is the distribution of particles having field properties intrinsic to them, we should never confuse a measure of something with tangible things because this obviously leads to a great deal of confusion :D. As such I am not overly pre-occupied with simple equations, terminology or measures of things and concentrate on particles, their fields and the field interactions. So to answer your question, how much energy can a discharging inductor gain?, it would depend on how much energy it had initially prior to charging, the extent of interactions as well as the extent of interaction with it's environment.

Quote
Or let me rephrase it in Newtonian equilvalent
1/ How much energy does it takes to cause a mass M to velocity V from relative rest position.
2/ How much energy can we gain from stopping mass M with velocity V to its relative rest
This may be where our perceptions diverge, if you want to compare the property of inductance to a simple mass then the result will probably be exactly what one would expect however I look past this down to the fundamental interactions between particles and fields where things are seldom so cut and dry. Here is an example, take the inductor and add enough "energy" to have the material undergo nuclear fusion which liberates energy inherent in the matter stored from reactions which occured billions of billions of years ago in another part of the universe, how do these interactions relate to a simple mass M at a velocity of V?. You see the form of the energy input to the inductor was never defined nor was the magnitude and when these variables change we should expect our outcome to change as well, this is why I usually ignore the more simplistic "popular" understanding of things and concentrate on fundamental physics. I understand this example is a little extreme but I have found more than a few cases whereby a simple coil of wire can interact with it's environment and produce an energy gain but the devil is always in the details.
Regards
AC


---------------------------
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“The first principle is that you must not fool yourself and you are the easiest person to fool.”― Richard P. Feynman
   
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 :) Take it easy AC.
   
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  Good comments, will require digesting on my part.
This from Dumped was particularly insightful IMO, as was the url pointed to:


Quote
Our 'beginnings' are most often very short in understanding.  But
as we progress down the road of discovery we learn how things
work.  We adapt, we innovate, we adjust, we share.

For a new twist on 'coils' have a look HERE.

A few days ago, I was able to spend some time with the Tektronix 3032 and several variations on the basic JT circuit.  Measuring Pout, Pin and n as discussed above, I might summarize n values to show the spread in values obtained and recorded:

n = .81, .52,.59, .63, .52, .35, .45, .80, .13, .77, .61, .79, .88, .62, .94,  .99, .92, 1.0, .69, 1.06

So yes, there were some "interesting values", though I would say the last value is still consistent with unity (given the +-3% errors as previously stated, 2 sigma).
 
In the process of taking measurements, I realized the importance of reviewing HOW the measurements are taken, and the importance of simulations AS A WAY OF CHECKING THE MEASUREMENT METHOD, for example where the probes are attached.  Also, if there is an input of power in the circuit somewhere (and somehow) -- just how will this show up? as an increase in current at some point, or an increase in voltage along a path?  I think the latter, from observations, but all this has to be checked -- and then re-checked.

I believe simulations will help in this effort of re-checking.

This issue is so important that I propose to come back to this tomorrow on another thread I'll start -- "Measuring Pin, Pout, n -- Simulations etc."

 
   

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It's not as complicated as it may seem...
 
In the process of taking measurements, I realized the importance of reviewing HOW the measurements are taken, and the importance of simulations AS A WAY OF CHECKING THE MEASUREMENT METHOD, for example where the probes are attached.  Also, if there is an input of power in the circuit somewhere (and somehow) -- just how will this show up? as an increase in current at some point, or an increase in voltage along a path?  I think the latter, from observations, but all this has to be checked -- and then re-checked.

I believe simulations will help in this effort of re-checking.

This issue is so important that I propose to come back to this tomorrow on another thread I'll start -- "Measuring Pin, Pout, n -- Simulations etc."

Sounds like a very good plan Professor.  O0 I'll help out where I can.

One thing I will suggest, is that you try the RC filter/two-DVM method for obtaining a Pin figure. I will draw up an amendment to the schematic to show exactly how to do it. This will not only provide you with another method to obtain Pin, but a way of checking your scope Pin measurements. If you do not have two DMM's (digital multi-meters), you can buy them quite cheaply. As a bonus to this method, not only is it inexpensive, accurate, and accessible (not requiring a scope channel), it allows more freedom as to where and how the Pout can be measured, because there is no longer a common ground between the two measurements, i.e. the scope grounds always limit this flexibility. The Pin measurement is essentially "floating" wrt the scope ground.

.99


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Hi all,

i did some experimenting on the "groundloop special" aka the Hartley osc. circuit.   The overall the results are not very impressive.

As i have no rocksolid method of determining the efficiency (n) of this circuit i should be carefull, but via severall methods, the "n" was in the 42% range.
   
Peak voltages are high (up till 10 Vpp), but it drops fast when putting a load (led) on the output.

I also tried a joule thief as a load to this GL circuit, but allthough it was able to run this JT, the input power into the JT (= output power from GL circuit) dropped to 800mV.

Also the added L3 coil and the feedback to the battery did not improve the overall "n".
It seems that the resonance of the L3 coil (i tried severall) does not have a big impact on the frequency this circuit oscillates on, nor does the feedback diode to the battery seem to prolong the discharge time.

Well anyway, it was fun experimenting with it, but i will continue looking into the LTJT2 circuit now.

Video of the above experiments to be seen here: http://www.youtube.com/watch?v=0ntFxscwi00

Regards Itsu.
   
   
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  I enjoyed your latest video, Itsu, and your comments.  I have some results on the same circuit, with different values tho for components, here:

http://www.overunityresearch.com/index.php?topic=773.msg12313#new

I have found that this circuit is particularly sensitive to the L of each coil... 

Also, I raise several questions there, and .99 has provided particularly helpful input.
   
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Quote
In the process of taking measurements, I realized the importance of reviewing HOW the measurements are taken
-PhysicsProf

Absolutely.  That 1.06 figure is interesting, but within the range of error, as you mentioned.  Bolt has said that a carefully tuned JT can get over 100% COP, but not much above that.  I do not know if that claim is accurate or not, but I absolutely respect Bolt's abilities.  So this may in fact be true, that a carefully tuned JT can exceed COP=1.  I suppose that's why we are here experimenting.  I am curious as to whether your COP=1.13 figure was a measurement anomaly or not, as it's outside that +/- 3%error range.

Was there any significant waveform difference between the COP=1.06 / COP=1.13 figure and the others?   For example, maybe this have something to do with the voltage/current phase of the circuit's self-oscillation.

One thing that is occurring to me lately, is that for any 'method' that provides COP>1 (which I believe there are several existing already, for example HHO into a generator) must provide higher than about COP>2.0 or COP>2.5 to become an effective self-runner , due to inherent conversion losses (rectification, etc) as well as losses due to heat, leakage flux, etc .

My ultimate goal is to open-source a solid-state self-running circuit , and I'm not sure JT will be able to provide this level of performance.  It is useful however, for basic research , due to its simplicity and easy replication.

Overall Plan:

Currently, I'm experimenting with electromagnets (and experimental behavior of ferrite in near-saturation and saturation states), as well as behavior of a pulsed electromagnet in the higher-voltage range (63V DC or so).  I built a 555 PWM circuit over the weekend, which can provide simple pulsed DC for a variety of experiments in the range of 200hz - 2khz.

I'm also winding an electromagnet on ferrite with 26/28 AWG magnet wire, but this takes forever , due to the wait for the superglue to set (each 8 winds takes about 5 minutes).  So this is a bit tedious, but I think it will be worth it due to the experience gained in craftsmanship.

JT Plan:

I may try to do another JT circuit this week as I wait for these electromagnet windings to set, though I'm curious as to the most important information that would be useful for basic research in JT circuit / blocking oscillator.  

I think circuit resistance / capacitance / inductance vs frequency might be a good bet, as with the equipment I have now I can confirm (or disprove) the formula provided on Wikipedia.   Sometimes Wikipedia can be a very good source of information, but other times it can be a source of profound disinformation and error, so I think it would be useful to try to verify some of the 'official knowledge' regarding Joule Thief via experiment.

Quote
The oscillating frequency (in Hz) is approximately equal to the battery (or source) voltage (in volts) multiplied by the battery's Thévenin-equivalent resistance (or output impedance) (in ohms), divided by the transformer's mutual inductance (in Henrys).
http://en.wikipedia.org/wiki/Joule_thief

Is the above claim accurate? This might be a good place to start.

According to Wikipedia,
Quote

JT_osc_hz = V_battery * R_battery
            ---------------------
            T_mutual_inductance

V_battery = Battery Voltage
R_battery = Battery's Thevenin Equiv. Resistance (aka Output Impedence)
T_mutual_inductance = F0 = (Vs*Rs) / Lm



http://en.wikipedia.org/wiki/Joule_thief

Knowing whether this Wikipedia article (specifically, the oscillation formula) is 'accurate' (aka. experimentally predictive) or not might be the best way I can contribute for the time being.



« Last Edit: 2011-03-22, 16:49:04 by feynman »
   
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Absolutely.  That 1.06 figure is interesting, but within the range of error, as you mentioned.  Bolt has said that a carefully tuned JT can get over 100% COP, but not much above that.  I do not know if that claim is accurate or not, but I absolutely respect Bolt's abilities.  So this may in fact be true, that a carefully tuned JT can exceed COP=1.  I suppose that's why we are here experimenting.  I am curious as to whether your COP=1.13 figure was a measurement anomaly or not, as it's outside that +/- 3%error range.

Was there any significant waveform difference between the COP=1.06 / COP=1.13 figure and the others?   For example, maybe this have something to do with the voltage/current phase of the circuit's self-oscillation.

One thing that is occurring to me lately, is that for any 'method' that provides COP>1 (which I believe there are several existing already, for example HHO into a generator) must provide higher than about COP>2.0 or COP>2.5 to become an effective self-runner , due to inherent conversion losses (rectification, etc) as well as losses due to heat, leakage flux, etc .

My ultimate goal is to open-source a solid-state self-running circuit , and I'm not sure JT will be able to provide this level of performance.  It is useful however, for basic research , due to its simplicity and easy replication.



The 1.13 was obtained with a JT circuit that somehow got into a mode where there was a significant out-of-phase relationship between output voltage and current, as described very early in this thread.  The 1.06 was obtained with the reverse-JT (inductors on the output side of the transistor), described in another thread regarding measurement of n, and again with that result, there was a significant out-of-phase (OOP) relationship between output voltage and current...  I have found that CAPACITANCE added to the circuit has this effect generally of producing the OOP, and I note that the inductors themselves have capacitance -- which is dependent on the frequency...


Quote
  Feynman:
Overall Plan:

Currently, I'm experimenting with electromagnets (and experimental behavior of ferrite in near-saturation and saturation states), as well as behavior of a pulsed electromagnet in the higher-voltage range (63V DC or so).  I built a 555 PWM circuit over the weekend, which can provide simple pulsed DC for a variety of experiments in the range of 200hz - 2khz.

I'm also winding an electromagnet on ferrite with 26/28 AWG magnet wire, but this takes forever , due to the wait for the superglue to set (each 8 winds takes about 5 minutes).  So this is a bit tedious, but I think it will be worth it due to the experience gained in craftsmanship.

JT Plan:

I may try to do another JT circuit this week as I wait for these electromagnet windings to set, though I'm curious as to the most important information that would be useful for basic research in JT circuit / blocking oscillator. 

I think circuit resistance / capacitance / inductance vs frequency might be a good bet, as with the equipment I have now I can confirm (or disprove) the formula provided on Wikipedia.   Sometimes Wikipedia can be a very good source of information, but other times it can be a source of profound disinformation and error, so I think it would be useful to try to verify some of the 'official knowledge' regarding Joule Thief via experiment.

Is the above claim accurate? This might be a good place to start.

According to Wikipedia,
Knowing whether this Wikipedia article (specifically, the oscillation formula) is 'accurate' (aka. experimentally predictive) or not might be the best way I can contribute for the time being.

We've talked about the formula in Wikipedia, and I found it was not accurate.  I've done some further checking this morning with a simple JT circuit, no caps added, MPS2222 transistor, 500 ohms R to base.  Here are the data I obtained using a power supply to vary the input voltage:

Vin V      Frequency KHz
0.49V     625
0.56       363
0.61       282
0.78       182
0.91        150
1.00       135
1.1         122
1.15        118  = minimum frequency, found using the scope to catch f-min
1.27       123
1.35        133
1.45       147

Strikingly, the frequency DECREASES with increasing Vin from 0.49 to 1.15 volts in (for this particular set of parameters), contrary to the prediction of the formula in Wikipedia -- then the frequency goes up again.

   
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@PhysicsProf

Quote
The [COP=]1.06 was obtained with the reverse-JT (inductors on the output side of the transistor)
-PhysicsProf

Interesting... so it seems there is (for now) no significant energetic benefit to using Reverse JT over a regular JT for testing.

Quote

The 1.13 was obtained with a JT circuit that somehow got into a mode where there was a significant out-of-phase relationship between output voltage and current, ...
there was a significant out-of-phase (OOP) relationship between output voltage and current...
-PhysicsProf

Okay, so I think we can infer the OOP condition is somehow critical to these anomalous COP>1 values.  It's happened multiple times now.  This is good becomes it gives us someplace to look.



Where did you add the capacitance , and in what ball-park (pF, nF, uF?)?

Thanks,
Feynman
   
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@PhysicsProf

Interesting... so it seems there is (for now) no significant energetic benefit to using Reverse JT over a regular JT for testing.

Okay, so I think we can infer the OOP condition is somehow critical to these anomalous COP>1 values.  It's happened multiple times now.  This is good becomes it gives us someplace to look.



Where did you add the capacitance , and in what ball-park (pF, nF, uF?)?

Thanks,
Feynman

  Good questions.  In testing the JT circuit, I added capacitance parallel to the L1 coil, also parallel to the L2 coil.  I have tried 1, 10, 100 nF in tests.   Note that these coils THEMSELVES have some capacitance, which is frequency-dependent interestingly.   I will be doing further tests at the University in the next few days and plan to report results in this forum.

   How is your work going, Feynman?  I hope well...  kindly point us to links for your work as it goes forward.
   

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OK,  i retested my JT with the bc547 and the mps2222a transistor, and used both the earlier used 1 ohm input resistor with scope measurements (98.5% see post #24), and the newly proposed Dual DMM method ("Reliable Measurements and Simulations: Power In and Out and Efficiency n"thread post #10).

Results with the 1 ohm-scope method was (multiplying mean V with mean i which seems to be wrong):
Pin:  1.276 x 0.013 = 0.016588 (16.5mW)
Pout: 1.272 x 0.013 = 0.016536
n is (0.016536/0.016588)100% = 99.6%

Results with the dual DMM method:
Pin:  1.3 x 0.008 = 0.0104 (10.4mW)
Pout: no way to measure using a 1 ohm output resistor as the Mean value fluctuates to much

But we see already a significant difference in the Pin measured with the 1 ohm r/scope method compared to the Dual DMM method (16.5mW verses 10.4mW).

Similar results where obtained when using a MPS2222a transistor:

result with 1 ohm-scope (wrong):
Pin:  1.275 x 0.011 = 0.014025 (14mW)
Pout: 1.261 x 0.011 = 0.013871
n is (0.013871/0.014025)100% = 98.9%

Results with the dual DMM method:
Pin:  1.303 x 0.0082 = 0.0106846 (10.6mW)
Pout: no way to measure using a 1 ohm output resistor as the Mean value fluctuates to much.

Also here big difference in the 2 used input measurement methods.

See the attachments on the used measurements methods.
Waiting for a clever way to accurately measure both Pin as Pout.

Regards Itsu

   

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It's not as complicated as it may seem...
Itsu,

I wonder if you have some offset in your scope channels? This might explain the discrepancy between the DDMM method, and the scope method.

Try this test on your scope:

1) connect the scope ground lead to the probe tip. Set the time base to 1ms or so.

2) set the vertical gain on that channel to the highest setting (i.e. most sensitive).

3) move the zero reference tick (left cursor) to the center line on the display and note what the offset is on the scope trace.

.99


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Poynt99,

i am impressed, as indeed my channel 1 probe had a (slight) offset.
It came out clearly with the method mentioned (Hor. 1mS, vert. 2mV) as it was half a div. down (1mV).
After auto calibrate it was solved.

Now i have to redo my tests  :-\

Regards Itsu

   

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It's not as complicated as it may seem...
Itsu,

I was hoping it might be more on the order of 5mV or so, to make up for the difference between the scope and the DMM. Not to say that the DMM is perfect either.

Cheers,
.99


---------------------------
"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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PhysicsProf:

Quote
We've talked about the formula in Wikipedia, and I found it was not accurate.  I've done some further checking this morning with a simple JT circuit, no caps added, MPS2222 transistor, 500 ohms R to base.  Here are the data I obtained using a power supply to vary the input voltage:

Vin V      Frequency KHz
0.49V     625
0.56       363
0.61       282
0.78       182
0.91        150
1.00       135
1.1         122
1.15        118  = minimum frequency, found using the scope to catch f-min
1.27       123
1.35        133
1.45       147

Strikingly, the frequency DECREASES with increasing Vin from 0.49 to 1.15 volts in (for this particular set of parameters), contrary to the prediction of the formula in Wikipedia -- then the frequency goes up again.

You are missing some key points here.  When you are in the sub-one-volt range and looking at the Joule Thief frequency you are outside of the normal voltage range for operating the Joule Thief.  The formula probably assumes 1.25 volts and higher.  That's because the transistor will operate correctly in this range.  Below that supply voltage and you are in a region where the base-collector diode of the transistor may not conduct normally hence the observed frequencies.

The frequency was increasing above 1.25 volts in your observations and that is in line with the formula.

I am also going to assume that you ignored the battery output resistance component of the formula and connected the power supply directly to the Joule Thief.  You should put a resistance in series with the power supply output to emulate the output resistance of an AA battery.  You would have to look it up but I will hazard a guess that the output resistance for a fresh alkaline AA battery is a few ohms.  So you can experiment with a series resistor of that value and higher.

As long as you are in the normal operating voltage range and the normal battery output resistance range you should see that the formula holds true.  Note that the formula gives you an approximate frequency and other parameters that have slight effects on the Joule Thief operating frequency are ignored.

MileHigh
   
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Posts: 805
Somebody else said this as well, 

You can not average the current and voltage separately, and then multiply the values together to get average power.  No no no.

AVG(I) * AVG(V)   not = to  AVG(I * V) in all cases.

so even though I endorsed the RC filtering approach before, for the 1 ohm resistor, I realized this is an erroneous approach because the voltage does fluctuate a little bit. If it would be constant than maybe.

EM
   
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Posts: 2995
Somebody else said this as well, 

You can not average the current and voltage separately, and then multiply the values together to get average power.  No no no.

AVG(I) * AVG(V)   not = to  AVG(I * V) in all cases.

so even though I endorsed the RC filtering approach before, for the 1 ohm resistor, I realized this is an erroneous approach because the voltage does fluctuate a little bit. If it would be constant than maybe.

EM

I'm well aware of this EMDevices, and I'm not making that mistake.  I let the Tek 3032 take V(t)*I(t) giving the power waveform and then it calculates the Mean(V*I) over a number of cycles.  Or one cycle if I select that.

MH: 
Quote
The formula probably assumes 1.25 volts and higher.

Then the formula should state what it assumes.  I would take a data table like the one I produced EXPERIMENTALLY over a formula like that any day -- because a data table tells me what to expect over a range of input voltages (no guessing at assumptions).
   
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Dear PhysicsProf,

Now that I have completed the simple computer model that conclusively showed that kinetic energy of air molecules can be brought-in via two or more tuning forks in resonance.

I can confidently project that:

1.   An LCR circuit can be compared with a Tuning Fork.
2.   If we need two or more tuning forks to resonate and bring-in energy, we shall need two or more LCR circuits.
3.   You have been working on the simple Joule Thief circuit for some time.  You did the experiments in a vigorous and scientific way.
4.   Now should be a good time to introduce another LCR circuit to see if you can get the two LCR circuits to resonate.  (FLEET or LTJT is a possibility.)
5.   I believe that the Steven Mark Device is a two LCR circuit in resonance.  A Chinese Researcher indicated that he had some luck with that approach.  Theoretically, two or more LCR circuits will be closer to the tuning forks in sympathetic vibrations.

I do not have the equipment in USA to check it out yet.  You and others may be in a better position to experimentally check it out first.

Regards,

Lawrence
 O0
   
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Posts: 2995
Dear PhysicsProf,

Now that I have completed the simple computer model that conclusively showed that kinetic energy of air molecules can be brought-in via two or more tuning forks in resonance.

I can confidently project that:

1.   An LCR circuit can be compared with a Tuning Fork.
2.   If we need two or more tuning forks to resonate and bring-in energy, we shall need two or more LCR circuits.
3.   You have been working on the simple Joule Thief circuit for some time.  You did the experiments in a vigorous and scientific way.
4.   Now should be a good time to introduce another LCR circuit to see if you can get the two LCR circuits to resonate.  (FLEET or LTJT is a possibility.)
5.   I believe that the Steven Mark Device is a two LCR circuit in resonance.  A Chinese Researcher indicated that he had some luck with that approach.  Theoretically, two or more LCR circuits will be closer to the tuning forks in sympathetic vibrations.

I do not have the equipment in USA to check it out yet.  You and others may be in a better position to experimentally check it out first.


Regards,

Lawrence
 O0

Yes, I would like to try something new, Lawrence, and I'm certainly willing to look at the two-LCR circuit.  (Thanks for sending me some detail via email.)
It will be a few days before I can get set up and testing, including a decent signal generator for this purpose...  I now have two air-core inductors for this purpose, and a ferrite rod.

I'm also curious how Feynman's effort to replicate the Gabriel device is faring...?
   
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Lidmotor posted a variation of the basic JT circuit that I find fascinating... and invite comments.  His video is here:
http://www.youtube.com/watch?v=-FoQWCzfq1w

You will note that he demonstrates (not a theoretical claim alone) that once the resonator rings, he can remove the 20Kohm resistor to the base -- and it keeps going...

From his vid, I extracted the schematic (attached).

I did a replication using an MPSA06 transistor, 17Kohm R, red LED.  And three different tries at an inductor.  No success yet in lighting the LED.  Any ideas?  Does anyone know on which forum this is being discussed also?
It may be that one needs to use an air-core inductor and movable core -- and "tune" it in...  I haven't tried that yet.

I found the short across the diode to be very strange.  -- but this from comments on the vid:

Hello PhysicsProf

The led should be from the emitter to the base through a 1n4148 diode.

The L1 coil is is only one layer with the one end free for the AV plug or FL tubes.

Once this is started you can remove the base resistor.


   
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