Is joule thief circuit gets overunity?

[MileHigh]

TK:

In your coil resonance clip your excitation from your signal generator should have been a sine wave.  That's actually of critical importance and I assume that you know that.

MH

[TinselKoala]

Nice tip. I have not seen the video yet BUT the explanation is very very good. So you replace the signal that drives the Coil with an FG and look for the best output in voltage with the other probe?

Yes, that's right, essentially. With the scope probe on the second coil.

Just like if I just put one coil with the FG and probe across coil input and look for the highest voltage pk-pk. The exact same thing but with yours I can do that on the circuit, right?

Hmmm.... With a single winding? I'm not so sure that is equivalent. I'll have to do some comparisons to check. For a single coil I usually make an improvised "primary" with a few turns of scrap wire, and feed that, thru a 50R resistance, with the FG output. Then look for resonant rise on the original coil as usual. This will probably also work for coils that are in-circuit, but be careful that the resonant rise doesn't blow up stuff downstream or overload your scope probe.
For, eg, Tesla coil secondaries, I use a 1meg or 10meg resistor in series with the already 10x attenuated probe tip at the top of the secondary, and just use a single loop or two around the base of the coil as the FG-driven "primary" (with the 50R in series).

I must admit this is probably for the engineers a must have babe steps learning thing, but for me it has been very valuable to learn a little bit more today.

Fausto.

I am glad. I hope the information is useful, and thanks so much for the feedback. The DeepBunker can be a cold and lonesome place at times, even with a good dog at my feet.

[TinselKoala]

@Lawrence: You might try the MPSA18 in place of the 2n2222 or 2n2222a for your low-voltage, low current models. I find that it works better, but it is also more delicate. It is also a lot cheaper.

I just bought a new 2n3055 today from my component supplier. It cost 4.85 US, plus tax. Outrageous! The MPSA18 can be had for fifty cents each or even cheaper. A lot of 25 for under four dollars on Ebay, I see.

Don't worry, I won't be competing with you. Just try to have fun, and I wish you the best of success and happy experiences along your quest.

[plengo]

Fausto:

Back to the exploration.  I will state it again, you should be doing this and not me.

The web page to calculate the inductance of a coil:

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/indsol.html#c1

For a coil length of 50 cm, radius 50 cm, with 1000 turns, (3.14 km wire length), air core, the inductance of the coil is 1.97 Henries.  I believe that is much less inductance than you were expecting.

Let's assume that Joe is using 12 gauge wire with a 3 mm diameter.  12 gauge wire has 0.1588 ohms resistance per 100 feet.  3.14 km is 1.95 miles.   1.95 miles is 10296 feet.

Therefore the resistance of the coil is (10296/100) x 0.1588 = 16.35 ohms.

So, what happens when you put 255 volts across the coil?

The time constant is L/R = 1.97/16.35 = 0.12 seconds.   So five time constants is 0.6 seconds.

Therefore after 0.6 seconds the giant coil could have 255/16.35 = 15.6 amperes of current flowing through it.  I don't think the alkaline AA batteries could put out 15.6 amperes.  I am guessing they start to strain around 7 amperes.

The rotating magnet can add some counter-EMF to reduce the current flow.  The giant rotating magnet might also increase the length of the time constant due to increased permeability to reduce the rate of increase in current flow.

That doesn't matter.  My conclusion is that you have always viewed the giant Newman motor with an emotional reaction and you never tried to do some very basic calculations to see what the results would be like.  That was a huge mistake on your part.   It seems pretty apparent to me that a bunch of AA cells in series can easily power the giant strange "Newman motor."  In reality the Newman motor is just an ordinary pulse motor that just happens to be so big that you have to move it around on the back of a pickup truck.   You pump somewhere between 50 and 200 watts into it, and it does between 10 and 20 watts of mechanical work to pump water.

Can you see how easy that was Fausto?  It's pretty clear to me that your assumptions were way off.  The mistake was to never try to model the motor and make some basic calculations.

Finally, in the chance that you don't understand the "time constant" references then I suggest that you go and study.  Every single pulse motor you will ever build has a time constant and it is critical to understanding how the motor works.  Without that level of understanding it's like you are flying blind.

MileHigh

I think you made a little mistake in your calculations but here it goes. On the picture I show your number for the resistance and mine and a little bit more.



It is very clear to me that with even 1/2 amp you will not be able to run that gigantic motor. I barely can run my toy motors with that much less with a load.


In the picture one can see that playing with gauge wires one can get what he/she wants concerning amperage.


In the picture I used first this site: http://en.wikipedia.org/wiki/American_wire_gauge and the second picture I used this site: http://www.cirris.com/testing/resistance/wire.html





Fausto.

[MileHigh]

Fausto:

If you switch to higher gauge wire the size of the wire gets much smaller.  36 gauge wire would most likely be too thin and too fragile for Newman's giant motor.

If you increase the wire resistance all that does for you is increase the battery power that is lost to heat and reduces the maximum current through the coil.  That reduces the strength of the magnetic field and therefore it reduces the strength of the motor.

Let's not forget what we are talking about:  Is the Newman motor demonstrating anything special or any over unity?

I showed you how in a few simple steps you can make some good estimates of how the motor is performing in real life.  When Joe Newman says that his "amazing" motor runs on voltage only or he says it runs on voltage with negligible current it's not true.

You listened to Joe and believed him and then you made a bunch of estimates and assumptions yourself about the motor that are not true.

The inductance calculator for a coil on the Hyperphysics web site is a valuable tool.   Once you know the output impedance of the voltage source that is charging the coil and the inductance of the coil then you know the L/R time constant and then you know how long it takes for the coil to reach the maximum current flow.  This is applicable to any pulse motor.

You made reference to how much voltage a "big coil" can produce.  The truth and reality is that just about any coil can produce high voltage when it discharges its stored energy.  The "big coil secret" that people like Bedini don't want to tell you is that the voltage the coil can product is not dependent on the coil, it's actually dependent on the load on the coil.  A high resistance load will result in high voltage.  A low resistance load will result in low voltage.  A short circuit for the load will result in zero volts output from the coil.  So yes, the same coil that can output thousands of volts can also output one volt and it can also "output" zero volts.  It all depends on the value of the load resistor.

MileHigh