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Author Topic: LTJT - poynt99 Tests #2  (Read 89553 times)
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Absolutely PhysicsProf, the curves are definitely more interesting than Wikipedia shows.  I realized that when I was experimenting with Joule Thief in the past.   Even if it was only 90% efficiency , I think it's a fascinating circuit, and it's a great way to get people involved in experimenting with electronics.  The evidence that it's COP>1 only adds to the mystery.

I will upload my scope traces over the weekend.  Unfortunately I only have one old Tektronix analog scope , so I had a single channel trace of the voltage of the transistor waveform and the LED waveform, but it's accurate down to nanoseconds, which is nice.

Great work guys, looking forward to moving my gear this weekend. 

   
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It's not as complicated as it may seem...
For low power such as the Joule Thief and for those that can measure resistance accurately:

http://shop.ebay.ca/?_from=R40&_trksid=p3984.m570.l1313&_nkw=carbon+resistors&_sacat=See-All-Categories#

50 Value 1/4W Carbon Film Resistor (1R~10MR) 5% 2000pcs
$10, free shipping.

Use parallel combinations to achieve your desired resistance.

.99
   
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  Interesting results yesterday as I traveled to the University and used the Tektronix 3032 there, to derive Pin and Pout mean values, as we have been discussing.

I will start with a few "normal results", in part to get us all used to reading the waveforms and the calculated power.

Result 1:  Using toroid "A" (from prototype A sent to me for testing by Lawrence Tseung; but just using the primary and feedback windings, not the secondary winding).  Attached shows the resultant waveforms and calculated Power, with the input Power in red on the left and the output Power in red on the right.  Channel 2 is always the voltage drop across the one-ohm resistor (see Lanenal's circuit diagram above in this thread), that is, the current waveform.  Here, a nice sawtooth.  Channel 1 is the voltage across the battery -- or, in these tests, the DC power supply -- for Pin, on the left.  For Pout on the right, Channel 1 is the voltage drop across the transistor and (red) LED.

Notice that per the schematic, the voltage across the 1 ohm resistor is Negative, hence both Pin and Pout show up as negative -- for the discussion that follows, and to be consistent with what we know, I will set the y axis to be POSITIVE DOWNWARDS consistent with the power in and out being positive quantities.  The shapes are interesting -- a saw=tooth for Pin and a single U-shape for the Power Out.

The 3032 calculates ch1*ch2 = V * I = Power and displays the result in RED waveforms, and it calculates the MEAN Power for us, given in the right- hand column.  Per our previous discussion, to a reasonable accuracy over a dozen or so cycles, we get:

n = Pin / Pout = 36.11/ 40.15 = 0.9.  

The estimated error, +- 2% based on .99's simulation and on the repeatablility I find for this ratio in these tests (for a given toroid and set-up).

High efficiency, but not surprising.

The second pair of scope-shots homes in on the input and output signals, showing detail.  This juxtaposition will be useful for later comparisons.
   
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  A photo for the set-up is given in the attached.   The circuit is straightforward, 2N2222 transistor, red LED, 1K ohm resistor to the base, 1 ohm resistor on input and output for measuring currents, bifilar wound toroid.

The photo shows the toroid which I wound, with the primary and feedback windings both having 24 uH... (data to follow for this toroid, called "eJ" ).
   
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  Data for this eJ toroid is shown in the attached, for input voltage from the power supply measured by an independent DVM as 0.993 volts.

Familiar sawtooth waveform for Pin, and U-waveform for Pout.  

Result 2:  n = Pout/pin = 39.64/44.08 = 0.90  = 90%

+- about 3%.

Ho-hum.... but there is more
   
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 More from the same toroid, this time at 1.04 volts from the PS:

n = 44.3/48.3 = 0.92

No surprises ... yet.
   
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  I want to show next that one can get variations in the waveforms by using different conditions -- which I demonstrate by looking at a transformer I and a friend extracted from a Fuji AA-battery-type disposable camera.  Here we used the outer pins for the primary and feedback inductors (numbered 1,4 and 2,5 on another diagram... I'll see if I can dig it up...).

  The waveforms become quite interesting, showing THREE distinct humps for both Pin and Pout -- see attached.  I show a detailed shot for a few cycles in the first attachment so you can see the detail.  The Fuji transformer likes sinusoidal-looking waveforms... ;)    Why? an interesting question.  Clearly the Pin and Pout waveforms can vary from what we see above.

 Notice that sometimes I vary the vertical scale for the power waveform display -- the scale shows up in red at that bottom of the scope-shot so you can keep track of this parameter.

Result 4, Fuji:  n = 24.2 / 29.2 = 0.83

+- about 3%.  I suspect the lower value follows from the resistance in the very fine wire used in the Fuji transformer.

   
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  Without further ado, let me share with you -- inviting comment -- the most interesting result of yesterday's (4 March 2011) tests at the University, using a Tektronix 3032 scope.

  Here I am using the eJ toroid that I wound.  I began with a Jameco toroidal inductor (100 uH, Jameco part # 386601), and wound fifteen windings bifilar of 22-gauge insulated (one with plastic, the other enamael) copper wire.  The inductance of EACH of my windings came out to 24 uH.  The Jameco winding is not involved in this test run, and the wires are left unconnected from this winding (which would be the secondary winding for a Tseung-type system).

I have given results with this SAME eJ toroid above... where we observed Pin as a simple sawtooth and Pout a single hump or spike.  Now -- please look closely at the waveforms for this run at 0.996 V (in from the power supply), in the attached.

First, we look at the detail for roughly 1.5 cycles in the first attached screen-shot.  The red Pin waveform is approximately what we have seen before, a saw-tooth pattern.   But the (red) Pout waveform is quite different!
Instead of a single hump or spike essentially bounded at zero-power as we have seen in the past, we now see a U-shape that significantly OVERSHOOTS ZERO, demonstrating current and voltage Out of Phase, as we also see comparing the voltage across the (LED+transistor) in yellow, and the current in the 1-ohm CSR shown in blue.  

Further, notice the oscillations/wiggles in the waveforms for the output power and voltage waveforms.  Very interesting.  To me, this is striking and rarely-seen behavior, and I have been working with these types of circuits for months now.

To get the efficiency with some accuracy, we have the Tektronix 3032 calculate Mean Power for both Pin and Pout over numerous cycles -- with this interesting result:

n = 44.8 / 39.8 =  1.13 = 113%

+- about 3% as previously noted.  


If you are visually comparing Pin and Pout waveforms in the attached, note that the scale in the screen display for Pin is 20 mVV whereas the scale for Pout is 50 mVV (which does not change the result above), which I did because the Pout curve was getting clipped on the 20mVV scale as i recall.

In order to encourage and facilitate comparisons, I include a final attachment which shows Pin and Pout for these data at 0.996V juxtaposed with the data for the same eJ toroid ran at nearly the same voltage (0.993 volts), but where the latter displays the "normal" pattern with just one spike.  The two waveforms in the center of this attachment (trace 2 and 3 ) give Pout and Pin both on the same scale, 50 mVV, to make visual comparisons more straightforward for you.  If you think the Tektronix 3032 may be making a mistake when calculating the Mean power in the case where the power is sometimes negative and sometimes positive, I invite you to evaluate the areas under the Pin and Pout curves for one cycle, subtracting the opposite-signed power region, and then evaluate n from this integral (that is, using n = Ein/Eout, as I have demonstrated before).  It would be a worthwhile check.  I have done this roughly, and the Tek 3032 calculation seems good.

You have a dozen questions?  I have many also...   ;)

After seeing this result, I returned twice to the same circuit and getting the voltage as close as I could, but could not generate the unusual "spiky" Pout waveform again in the limited time I had on the Tek 3032 at the University.  And those results came out with COP = n of about 90%.
I recall having seen such a waveform at home before, but I do not know just how to reproduce this spiky waveform  -- wish I did.  And I am very open to suggestions.

I will say that I looked first at the many-cycle Pout (attached), then looked at many-cycle Pin (moving the channel-1 probe to do so), then moved the channel-1 probe back in order to re-measure Pout and record the approx detailed Pout waveform (attached).  The Pout waveform remained the same over the several minutes required to do these measurements and record them on the computer, about 15-20 minutes.   So however I got in this mode, with the unusual waveforms, zero-crossing Pout and COP evidently greater than one, the condition remained for a while.

When I saw that n was coming out larger than one, I was a bit excited and did go back and get the detailed waveforms recorded.  However, I was thinking that I could simply come back later and get more data at this condition after running at other voltages, which was not the case yesterday afternoon -- I'm glad I got as much data as I did and recorded it for you all to see.  

Now the question is -- what does this all mean? and how can one get back to this out-of-phase relationship between V and I in the output circuit??   (I have reported this condition before as you may recall, some time ago, but that was with the LT-type circuit and this is a simple JT.)  

To me the result is striking and noteworthy and something of a breakthrough.  But can it be repeated?  Repeatability is a core requirement for solid science and progress.
   
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Thank you PhysicsProf, these measurements are great and the result is fascinating!  O0

Will study it more closely after come back from church.
   

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It's not as complicated as it may seem...
Some tests coming up...

.99
   
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  Experimental data are the key. 
It will be helpful to have these additional (V4 and V5 especially) measurements, .99.  Please show the waveforms, especially the power waveforms, for comparison with the data I obtained with the 3032.
   
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I'm not sure if I read the scope shots right -- the marks on the left margin of the shots, are they zero indicators? Could it be the case that there is an absolute bias of the scope measuring the voltage drop over CSR1? Also, from your reporting OU results:
To get the efficiency with some accuracy, we have the Tektronix 3032 calculate Mean Power for both Pin and Pout over numerous cycles -- with this interesting result:

n = 44.8 / 39.8 =  1.13 = 113%

+- about 3% as previously noted.  


I found that it is even higher from the readings on the right margin of the first shot attached to that same post:

n = 55.08/45.20 = 1.21 = 121%.

Am I getting it wrong? Sorry, I don't know much about scopes and I'm just hoping this result can stand scrutiny. Also, what is the sampling frequency of the scope shots? 100MHz? I don't know if I can afford a terribly high frequency scope.

lanenal
   
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n = 55.08/45.20 = 1.21 = 121%.


Not sure what you mean but I think n over many cycles to provide accurate calculation. 

The Out of Phase result puzzled me quite a bit.  It almost seems to me that that the current never passed through collector emitter.  The only logic I can come up with for now is the JT turned from pulsing resonant into an LC circuit using the base emitter flow.   ??? :-\
   
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Not sure what you mean but I think n over many cycles to provide accurate calculation.  
OK, I see -- so that reading was just calculated from the cycles seen on the shot.

Quote
The Out of Phase result puzzled me quite a bit.  It almost seems to me that that the current never passed through collector emitter.  The only logic I can come up with for now is the JT turned from pulsing resonant into an LC circuit using the base emitter flow.   ??? :-\

Me too -- it seems the current through the CSR1 is alternating? With the Diode and the transistor, I don't know how could the current flow in the other direction. Or am I reading the scope wrong again?

lanenal

P.S.: I saw a 200MHz two Channel Scope today, less than $100. But no Math capabilities. Nor can I download data onto a computer.
   
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what I'm thinking is like this

http://www.youtube.com/watch?v=kQdcwDCBoNY

but... still thinking :-\
   

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It's not as complicated as it may seem...
I've discovered the error in my test setup (scope grounds on wrong node), so here are the measurements again, as pertaining to "schema02", i.e. no CSR3 present.

Pitotal = -46.64mW
Pcsr1 = 2.79mW
Pvbat = 49.43mW [Note that you can obtain this value directly when measuring Pitotal just by inverting the CSR1 channel]

Pototal = 33.62mW (PLED and Pcsr2)
Pototal + Pcsr1 = 36.41mW

I did not measure PQ.

So, efficiency not including output power dissipated in Q is:

n = 36.41mW / 49.43mW
n = 73.66%

.99
   
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Lanenal:
Quote
I'm not sure if I read the scope shots right -- the marks on the left margin of the shots, are they zero indicators?
That is correct.  

Not sure what you mean but I think n over many cycles to provide accurate calculation.  

Right.

Quote
The Out of Phase result puzzled me quite a bit.  It almost seems to me that that the current never passed through collector emitter.  The only logic I can come up with for now is the JT turned from pulsing resonant into an LC circuit using the base emitter flow.   ??? :-\

Call it OOP... but not oops, at least not yet -- still checking various things.  I tried adding an "antenna" to the system in one of my tests, but the noise produced is nothing like that seen in the evident-n>1 test.  See my data from Friday (4 Mar 2011) repeated below -- compared with Pototal from .99's  post today (6 March).  The "input" power curves (on the left for each pair) look quite similar, as one might expect.  Our "output" power curves are inverted relative to one another, but taking that into account, these waveforms differ rather dramatically.  Mine shows the out-of-phase condition, evidently.   As I say, I don't know how to get the JT into this Out of Phase (OOP) condition that I achieved on Friday, but I'm thinking about GibbsH's suggestion as a possibility..... but how, Gibbs?
   
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@poynt99

Sorry to hear your measurements were incorrect.  That's happened to me before too, and it's disappointing.  Sometimes what I do is work on a few unrelated projects concurrently , so if one doesn't work out ,  I can take a break and come back to it.

@PhysicsProf

What you have accomplished -- if it is not due to errors in the setup -- is very significant.  What appears to me to be happening is that 'regular' Joule Thief is not OU, but due to some sort of phase anomaly (phase, frequency, and resonance seems critical in this sort of research), the joule thief circuit can slip into OU operation.

What we have are the scope traces, which are the most important information.  What I would suggest is that you attempt to replicate the experiment on a new circuit and toroid idential to the first  (same windings, etc).   That way you can make modifications and experiment without 'damaging' the original setup which produced OU.  At the same time, I would suggest you just continually run the original circuit in the same place on the same scope and see if it gets 'pushed' back into OU.

Here's what I would consider as possible sources that could have 'pushed' Joule Thief out of phase into anomalous operation:

1) Short-circuit, whether through the human body, oscilloscope, or otherwise.  This needed only to be temporary short circuit to get the circuit out of phase, such as brushing against two circuits leads with your fingers  (human body is 100ohm - 100k resistor).
2) RF energy in proximity.  For example, cell phone, radio waves, CD-R burner, etc.
3) Simple probability (0.5% probability of slipping into OU operation over 24 hour period.  etc)

Those are my suggestions for the time being.   Let's also make copies of your scope traces and work, and try to meticulously document the exact setup (schematic, scope probe points, probe types/impedence, photographs, etc).  I will definitely attempt replication.

Thank you again for your efforts;  I am following this with great interest.   Furthermore, for anyone interested in OU research , there is an excellent Torrent containing Nikola Tesla documentaries and patents which is available here:

Nikola Tesla Books and Other Video:
http://thepiratebay.org/torrent/4755412

The above is a great source of inspiration if you are feeling down due to engineering problems.   Tesla faced much worse (his lab with a lifetime of work burned up in a fire), and yet he still triumphed.
   
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Poynt:

I am not really following the thread but congratulations on finding the error.  73% sounds right, 99% sounded wrong.

I don't know if Murphy's Law is to blame but for such a simple circuit it has really been a struggle, don't you think?

Feynman and PhysicsProf:

Quote
due to some sort of phase anomaly (phase, frequency, and resonance seems critical in this sort of research), the joule thief circuit can slip into OU operation

There is really no chance that Feynman's speculation is true.  I admit I have not been reading or looking at the scope shots.  What I gather from skimming through the thread is that PhysicsProf has been reporting over unity results for the past week or more.

Look at the lesson in Poynt's experience.  With perseverance and more investigation you should figure this enigma out.  I realize that I am just parachuting in here but mark my words, there is no over unity associated with PhysicsProf's testing.  It's just a question of honing your skills and finding where you made an oversight.

MileHigh
   

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

It was those pesky grounds again. It's a good thing I re-drew the schematic without them, as it helped me find my error. Paying attention to the diagram in some detail is worth the time, I'm discovering. ;)

The numbers do seem to correspond to more commonly-achieved efficiencies now, agreed.

.99
   
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Quote
"
Look at the lesson in Poynt's experience.  With perseverance and more investigation you should figure this enigma out.  I realize that I am just parachuting in here but mark my words, there is no over unity associated with PhysicsProf's testing.  It's just a question of honing your skills and finding where you made an oversight."

I welcome skepticism , but I don't take kindly to those involved in IO.   Upon what basis  are your categorical blanket statements?   If it's non-experimental law of thermodynamics claims  , please start a new thread.  I do not want to discourage research in promising areas (sharp gradient DC in toroids). 


@PhysicsProf

It just occurred to me that what you ought to do is add a variable component to the circuit ... perhaps a variable resistor, variable inductor, or variable capacitor.    This allows tuning like in the video GibbsHemholtz posted.
   
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I welcome skepticism , but I don't take kindly to those involved in IO.   Upon what basis  are your categorical blanket statements?   If it's non-experimental law of thermodynamics claims  , please start a new thread.  I do not want to discourage research in promising areas (sharp gradient DC in toroids). 

I don't know what "IO" is.  The basis behind the statement is that an inductor can only put out as much energy as you put into it.  It's a device that can store energy and then release that stored energy.  It cannot create energy or harvest energy from "somewhere else."

You can easily do experiments to confirm these properties of inductors on the bench, and yes they do adhere to the laws of thermodynamics.  It's tempting to think that "sharp gradient DC in toroids" can be considered a promising area of research.  However, I think if you do do the research you will not find anything there.  It's a cliche about sharp gradients accessing otherwise hidden vacuum energy.

Anyway, with perseverance PhysicsProf should start seeing some numbers that refute his current findings suggesting over unity.

MileHigh
   
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Call it OOP... but not oops, at least not yet -- still checking various things.  I tried adding an "antenna" to the system in one of my tests, but the noise produced is nothing like that seen in the evident-n>1 test.  See my data from Friday (4 Mar 2011) repeated below -- compared with Pototal from .99's  post today (6 March).  The "input" power curves (on the left for each pair) look quite similar, as one might expect.  Our "output" power curves are inverted relative to one another, but taking that into account, these waveforms differ rather dramatically.  Mine shows the out-of-phase condition, evidently.   As I say, I don't know how to get the JT into this Out of Phase (OOP) condition that I achieved on Friday, but I'm thinking about GibbsH's suggestion as a possibility..... but how, Gibbs?


Of course your data is differ from .99's data although the current inverted looked just like yours. lol and it's obvious that .99 is anti cop>1  ;D sorry Poynt, it's just a personal opinion.  :P  In your data, current rise from zero to max while collector emitter voltage is high (seems like LED is on) and dipped negative when current drop.  That's the total opposite from other data. I still cannot comprehend it fully.  I do have opinions that the mode of operation (psuedo resonance/OOP) is rather rare.  I don't expect we can reproduce them easily and I don't plan to go that route if we don't have to.  I do strongly believe it has something to do with the youtube vid I  posted.  I'm thinking we reproduce  the circuit in the youtube vid and replace the cap with an LED, then insert a resistor to measure current from the input and output similar to the JT while pulse it with DC...

Edit:  Sorry Poynt   :-[ I know deep down inside you believe all the energy should add up.  We're brothers on this one. 
« Last Edit: 2011-03-07, 03:06:35 by GibbsHelmholtz »
   
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Of course your data is differ from .99's data although the current inverted looked just like yours. lol and it's obvious that .99 is anti cop>1  ;D sorry Poynt, it's just a personal opinion.  :P  In your data, current rise from zero to max while collector emitter voltage is high (seems like LED is on) and dipped negative when current drop.  That's the total opposite from other data. I still cannot comprehend it fully.  I do have opinions that the mode of operation (psuedo resonance/OOP) is rather rare.  I don't expect we can reproduce them easily and I don't plan to go that route if we don't have to.  I do strongly believe it has something to do with the youtube vid I  posted.  I'm thinking we reproduce  the circuit in the youtube vid and replace the cap with an LED, then insert a resistor to measure current from the input and output similar to the JT while pulse it with DC...

Interesting, thanks, Gibbs.  I like that circuit also -- will build it, too.  One should start a separate thread for it -- whoever replicates it first, OK?

Quote
I admit I have not been reading or looking at the scope shots.  What I gather from skimming through the thread is that PhysicsProf has been reporting over unity results for the past week or more.

Look at the lesson in Poynt's experience.  With perseverance and more investigation you should figure this enigma out.  I realize that I am just parachuting in here but mark my words, there is no over unity associated with PhysicsProf's testing.  It's just a question of honing your skills and finding where you made an oversight.

MileHigh

So long, MH.  When you want to look at my scope-shots and data, you're welcome back.

There are some good ideas that evolve from discussing actual circuits and data, and I appreciate this feedback, including lanenal, feynman, .99 and Gibbs.

The little JT circuit is a self-resonator...  seeks out a resonance rather quickly with major variables being the toroid windings, input voltage and resistance going into the base from the feedback-loop.  All easy to change.
Getting at the OOP condition is difficult -- I've been playing with the circuit for several hours since Friday, looking at it with my 60 MHz Atten DSO, with no success-- on that circuit from Friday.  
Besides, I think the point is that condition was reached and we -- I - am looking for a way to get there reliably and repeatably.

And I found something, inspired by comments on the LED being a diode -- it must be a leaky diode to permit the OOP condition (I think, may be wrong about that).
Anyway, I just replaced the LED with a RESISTOR, same circuit otherwise.   The JT works fine, self-resonates readily with a resistor in place of the LED.
With a 10-ohm resistor replacing the LED, call it Rout, using my ATTEN, I find the input and output powers at about one based on areas under Pin and Pout, but I'll wait till I get back to the 3032 to get numbers.


Furthermore -- with this Rout as a variable 1K-ohm resistor, I can see how the waveform varies as I vary Rout.  Very interesting...  and I can get an Out-of-Phase condition quite easily with this Rout!  (Although it does not have the same waveform as Friday's exactly...)  So that is progress and as I say, the idea came out of this discussion.  


PS -- the Tek 3032 I use is a 300 MHz oscilloscope... glad I can use it, when I get up to the University!

   
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