Tesla's "COIL FOR ELECTRO-MAGNETS".

[conradelektro]

I would be interested to see if you can detect any voltage difference when your two coils are open, rather than feeding a load.

TinselKoala: please see the attached drawing. Is this the measurement you wanted? (No difference in Voltage. But I am not sure what "open coil" means for a measurement. The instrument "closes" the coil with its "inner resistance" of about 1 M.)

May be my rather small pan cake coils do not show the differences well enough. Please specify a "solenoid coil" I could wind (one bifilar the other monofilar, otherwise identical).

I can offer a 10 mm Ferrite core (not sure which Ferrite it is, I bought these cores on ebay) or a 10 mm iron core made from a bundle of iron wire. The 10 mm core would be removable, so that I can test air core, Ferrite core and iron core (bifilar and monofilar).

Greetings, Conrad

[gyulasun]

Hi Conrad,

You have made very nice pancakes. I agree with all your measurement results.

One more thing: when you have some time try to "measure and calculate" the two pancakes self capacitance, you can use my earlier links as a guide, or using perhaps the resonant circuit you showed above but with a much lower value tuning capacitor instead of the 1 uF.   I mean the resonant frequencies may fall too close to each other to discernate between them by fine tuning the generator when using the 1 uF but you can use it first of course and see how it goes. IF needed, you could use a few nF capacitor too instead of the 1 uF (and remember the scope probe input capacitance is also there all the time as explained in the earlier links).  The explanation is that for the bifilar pancake the resonant frequency is lower with the same tuning capacitor you use for the monofilar because the bifilar surely has a higher self capacitance.

Greetings,  Gyula

[TinselKoala]

@Conrad: Yes, that's the measurement I wanted, thanks. It seems that you are not seeing the effect that "gestalt reality" demonstrates. Perhaps because the frequency is not right? My "hunch" is that smaller (lower inductance) coils will need a higher magnetic field frequency to show the effect.... and he is using around 850 Hz to your 30.

I don't know what kind of solenoidal coil to suggest. Nor do I know whether the result obtained in the video depends on the frequency and/or strength of the magnets. The video does show a large, clear and remarkable difference between the two coils when they are not loaded except by the voltmeter. Not only does the bifilar coil produce much higher voltage than the monofilar one, it also takes more shaft power to drive the rotor to the same RPM. (This appears to be the key to the "acceleration under load" effect: electrically loading the bifilar coil with a low-impedance load seems to cancel whatever its effect is and makes it look like a monofilar coil in terms of performance, which reduces the shaft load to turn the rotor and allows acceleration for the same input power.)
The coils he's using have lots of turns on them, and metglas cores; this may also be important. He says in the video that the effect depends on various factors, among them the rotor speed. Even with the bifilar coil his rotor needs to be going fast enough to give that 800-850 Hz AC at the output, in order to see the effect, and with some cores I think he said he wasn't able to see it at all.
It's an interesting phenomenon for sure. I think that "gestalt reality's" video is the most significant thing I've seen concerning the bifilar coil controversy in a long time.

[conradelektro]

@Gyula: thank you for the hints, I will try the resonance measurement with a 10 nF and with a 220 pF capacitor. And I have to look again at the measurement and calculation hints you gave at the beginning of this thread (which I have collected and stored). My scope probe has 6 pF parasitic capacitance.

@TinselKoala: I am still working on my magnet spinner, and I hope that I can get it to do 10.000 rpm (but I am waiting for parts, coupling between DC motor and axis of the magnet spinner).

What would be a good "solenoid coil" to test? I prefer the 10 mm core, because I have a Ferrite for it. I also have lots of 31 gauge wire. What are the ideal dimensions for a "pick up coil"? I remember that MileHigh mentioned it in one of his posts, I have to find it.

Metglas cores are a bit to steep at the moment, lots of other tests to do before going into that.

To get very high Voltage output I guess one needs very many windings on the pick up coil and a high spin rate of the magnet (I will not be able to do 800 Hz with my spinning magnets. I hope for 160 Hz ~ 10.000 rpm).

The idea is to also wind two "solenoid coils" (bifilar and monofilar, otherwise identical) in order to reproduce in principle the result from the 20-minute long "debunk" video.

But first I do more tests with my two pan cake coils. As always I am not a fast experimenter and the handling of the function generator is still new territory for me http://www.peaktech.de/productdetail/kategorie/dds-funktionsgeneratoren/produkt/peaktech-4060.871.html.

Thank you for the interest. I am already very pleased, I did not expect the two coils to be that identical, a surprise (but I am easy to surprise).

Greetings, Conrad

[conradelektro]

Same set up as in this post http://www.overunity.com/13460/teslas-coil-for-electro-magnets/msg382094/#msg382094

The coils are put at 9 mm distance from the spinning magnet, the magnet spins at 55 Hz (3300 rpm), the output (no shunt, TinselKoala calls that "open coil") is 128 mV for both coils (still no difference).

The output is over the high impedance of the instruments (which is about 1 Megohm for the scope probe, the Voltmeter has probably a higher impedance than 1 Megohm).

The scope measures 128 mV (true RMS) the digital Voltmeter sees 132 mV (for both coils, no difference at this measurement precision).


Concerning this "debunk video" http://www.youtube.com/watch?&v=kfRxsC9yumQ. The experimenter says exactly what always bothered me by this "speed up and input down experiments". What does it help that the speed goes up and the power input goes down as long as the output is way below the input?

Greetings, Conrad