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Author Topic: Tesla's "COIL FOR ELECTRO-MAGNETS".  (Read 505682 times)

conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #510 on: January 07, 2014, 08:20:51 PM »
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

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #511 on: January 07, 2014, 08:26:15 PM »
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

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #512 on: January 07, 2014, 08:38:36 PM »
@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

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #513 on: January 07, 2014, 10:46:48 PM »
@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

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #514 on: January 07, 2014, 11:55:27 PM »
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

MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #515 on: January 08, 2014, 12:46:30 AM »
Conrad,

You are doing an awesome job, your build skills are really good.  I am glad that you are having fun.

You made a reference to me stating that I posted something about an ideal coil configuration.  I am not sure what you read because the concept of an "ideal" coil configuration is something that needs some sort of frame of reference.

For example, lets suppose that there is a spinning pulse motor rotor with outward-facing cylindrical magnets on it.  Each magnet is say 3 cm in diameter.  In this case if you made a pick-up coil that was in the form of a ring (like a simple ring that goes on your finger), where the diameter of the ring was slightly larger than 3 cm, that would be an "ideal" configuration.

With a pick-up coil "ring" that was placed very close to the spinning rotor magnets, the coil would "see" the fastest possible changing flux with respect to time and hence generate the highest voltage peaks.   The more turns in the "ring" pick-up coil the higher the output voltage.  You make the diameter of the pick-up coil ring slightly larger than the diameter of the magnet so that the ring "sees" or "catches" all of the changing flux from the passing rotor magnets.

I suppose you could state that this is more of an "ideal geometry for creating high voltage peaks" and the number of turns is at the discretion of the coil designer.

MileHigh

MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #516 on: January 08, 2014, 02:21:59 AM »
TK:

Quote
@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 watched the clip and even through there are a lot of "holes" in the data gathered there is enough there to make some inferences that I am pretty confident are correct.

For starters, a test like this could be much more complete if you try varying the RPM of the rotor (he had a motor controller after all) and also by varying the load resistance on the coils.  The same old mantra, you vary the load starting from a short (just the wire resistance) to the matched load resistor (the wire resistance) to the higher value resistors and finally to open circuit.  All of that on top of the A-B comparison testing that he was doing between a regular and a bifilar coil.  He is a beginer experimenter so we will cut him lots of slack.

The big clue is the ozone and the very high voltage.

Here is what I think is happening:  By chance, with the open-circuit bifilar coil, the stimulation from the passing rotor magnets was quite close to the self-resonant frequency of the coil.  Perhaps it was a divide-by-n sub-harmonic of the self-resonant frequency.  So by chance the bifilar coil was being regularly pinged just at the right time and as a result the LC resonator voltage grew and grew until the air started to ionize.  You can see how adjacent strands of the very fine wire could have had 1K volts potential difference at the peak of the cap charge cycle.  Since air breaks down at about 20 kvolts per centimeter, it's not surprising that the air got ionized and started to conduct.

*Note also that the rotor magnet pinging was at quite a high frequency.  Chances are the period between pings was shorter than the time constant of the exponential decay of the LC self-resonance.  Hence the pinging was pumping energy into the LC resonator faster than it was decaying.  That means that the only place for the amplitude of the LC resonance to go was up.  At least it went up until the point where it "hit the wall" where the air itself started to conduct and act like a resistor.  Therefore the injected energy from each "ping" from a passing rotor magnet was being burned off in the ionizing air (and of course a small amount was being burned off in the resistance of the wire).*

So the big bifilar was cooking "itself," although in this case it was not due to the resistance in the wire, it was mainly due to the fact that the air itself trapped inside the coil was the resistor.  High voltage implies that the matched load has to be a high value of resistance.  Hence things fall into place:  The LC resonator potential increased to the point that the air started to conduct and do a "burn."  So, above a certain AC potential, the bifilar coil starts to see a "resistive wall of air" burning off the power.  The "wall" blocks the AC potential from increasing beyond a certain point.  The power being burned off was quite high, hence the increased Lenz drag on the rotor hence the dramatically increased mains power consumption of the drive motor.

If this theory is correct, then chances are if he changed the motor RPM by +/- 5%, then there would be no more sympathetically pinged LC resonance, no high voltage, no ionizing of the air, and therefore no high power burn in the ionizing air, no extra Lenz drag, and no high mains power consumption by the drive motor.

So, the moral of the story is that yet again, there is nothing special about the bifilar coil in Gestalt Reality's clip.  It's just a fluke that he was pinging the series bifilar coil and created "sympathetic vibrations" which increased the inter-filar voltage to the point that the air became something akin to an impedance matched resistor.  This could all be proven to be true if he simply plotted the open-circuit voltage of the self-resonating coil with respect to the rotor frequency.  Note also that if what I am saying is true, then his conclusions in his experiment are not quite right.  He doesn't really understand what he is observing.  However, ultimately this shows how there is nothing out of the ordinary about the bifilar coil in his experiment.  Mother Nature is playing out exactly the way she is supposed to be playing out and all of these seemingly unusual observations about the bifiar coil are 100% ordinary, expected, and explainable.

You would never see this happen with Conrad's setup.  He doesn't have the "mix" of components and excitation frequency and available power to get to the point where air starts to ionize and act like a resistor inside his bifilar coil.

MileHigh

conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #517 on: January 08, 2014, 09:19:47 AM »
@MileHigh: you mentioned in this reply http://www.overunity.com/13852/self-accelerating-reed-switch-magnet-spinner/msg380888/#msg380888

How much or how little energy a pick-up coil can output is primarily a function of the geometry of the coil, not the number of turns.  The main factor is the cross-sectional area of the coil that interacts with the external changing magnetic flux that determines the power output.

MileHigh

So, I wonder, what dimensions should a coil winding have to be a "good pick up coil" in my magnet spinner set up? Please see the attached drawing.

My magnet spinner set up is not an ideal "generator" (magnets around the rim of a disk would be much better). Nevertheless, I would like to find a good geometry for a pick up coil which would ensure a good "pick up of electricity" from the spinning magnet.

The idea is to wind two helical coils (one with a monofilar winding and the other with a bifilar winding, otherwise identical) in order to see differences or even the effect from the "debunk video". And the question is the geometry of the winding (length, thickness and the diameter of the hole for a core)?

I now do tests with my two pan cake coils, but later on I want to do tests with two helical coils.

Greetings, Conrad

conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #518 on: January 08, 2014, 03:28:40 PM »
I could do some resonance tests like TinselKoala did in his video https://www.youtube.com/watch?v=VpJwCNBHUh0 (Scoposcopy)

With a tank capacitor of 1000 pF and lower the two pan cake coils coils started to show differences.

I could also estimate the parasitic capacitance and the inductance of the two pan cake coils using this web site http://www.qsl.net/in3otd/inductors.html.

estimated parasitic capacitance
monofilar pan cake coil  174 pF
bifilar pan cake coil        229 pF

measured inductance both coils 34 µH

using this web site http://www.1728.org/resfreq.htm I could estimate the inductance:

monofilar pan cake coil: estimated 34 µH with 0.876 Mhz and 976 pf
bifilar pan cake coil: estimated 35 µH  with 0.862 MHz and 976 pF

monofilar and bifilar coil: estimated 35 µH with 266,5 KHz and 10 nF

I just realised: the resonance measurements with a 22 pF and a 3 pF tank capacitor are meaningless because the parasitic capacitance of the coils is around 200 pF.

Therefore the resonance frequency did not go up very much with a 22 pF or 3 pF tank capacitor. And estimates done with http://www.1728.org/resfreq.htm go badly wrong.

I am not so sure that one really can see a big difference between the two coils, with a tank capacitor bigger than 1 nF everything seems to be identical. And with a smaller tank capacitor (much below 1 nF) the measurements become unreliable.

Please see the attached drawings.

I will try this measurement soon: http://www3.telus.net/chemelec/Calculators/Interwire-Coil-Capacitance-Calc.htm

Greetings, Conrad
« Last Edit: January 08, 2014, 06:43:18 PM by conradelektro »

conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #519 on: January 08, 2014, 07:34:15 PM »
I tried to measure "interwire capacitance", please see the attached drawing.

Monofilar pan cake coil ~ 7 pF

Bifilar pan cake coil ~ 44 pF

http://www3.telus.net/chemelec/Calculators/Interwire-Coil-Capacitance-Calc.htm   calculator

Attached please find a PDF-file with all measurements and specs of the two pan cake coils.

Greetings, Conrad

gyulasun

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #520 on: January 09, 2014, 12:08:38 AM »
Hi Conrad,

Thanks for showing the measurements on the two pancake coils. 

For me, a coil normally has a self capacitance (I prefer using this term instead of the interwire or parasitic capacitance),  represented as a parallel capacitance with the coil itself.  This is what defines the first parallel resonant frequency for a coil when you do not connect any tuning cap to it, just excite the coil in a circuit which adds no any other capacitor to the coil and look for the parallel resonance like this link shows here:
http://www3.telus.net/chemelec/Calculators/Interwire-Coil-Capacitance-Calc.htm   

So I find it a bit unusual that the 'parasitic' capacitance values come out as 174pF and 229pF, while the interwire capacitance values come out as 7 and 44pF.  I will think this over how it could be explained, unless the measuring method for the parasitic capacitance inherently introduces some additional "error".

Could you measure the capacitance between any two wire ends of the bifilar coil?  Just do not couple or connect anything to it, and use your C meter between the two start wires or between the two end wires: possibly these two C values should be the same.  Practically you measure the capacitance between the two parallel guided insulated wires A and B.  (For all these C measurements you have to remove the jumper wire you use for the series connection of A and B wires/coil.)
Maybe you could check the C value between one start wire of coil A and the end wire of coil B too, (though I am not sure whether this C would be the same C as either the start or the end C value.)

Thanks,  Gyula

PS:  For you, the interwire capacitance and the parasitic capacitance mean a different capacitance? 

MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #521 on: January 09, 2014, 02:30:15 AM »
Conrad:

There is no true answer to your question about the "ideal" dimensions for a pick-up coil.  What I suggest that you do is that you make your two coils about fist-sized (you may have some empty plastic wire spools about that size?) and use a relatively small gauge of wire.  The reason that I am suggesting using a relatively small gauge of wire is to get a larger inter-filar capacitance so that you might have a chance of observing the effects of the capacitance in real-world tests (i.e.; not the self-resonance tests).

I will still pitch my "pet" concept:  You might get lucky and find some good wire on spools at an electronics hobbyist store.  Say you find a nice spool of 32-gauge single strand wire.  If you are really lucky you will find a very similar spool of 32-gauge speaker wire (two conductors).  So you make the simple connection with the speaker wire to create the bifilar coil.  If both spools have insulation that appears to be the same thickness and the same type of plastic then you will have two "instant coils," a regular monofilar coil and a bifilar coil.  If you are really really lucky you will be able to insert different core materials into the hollow centers of the plastic spools.

There is an interesting "Plan B."  Buy two identical spools of speaker wire.  On one of the spools do the bifilar connection.  On the other spool just use one of the two wires, or simply short the two parallel wires together at each end of the speaker wire to give you one-half of the resistance for the coil.  There is a distinct advantage to using light gauge speaker wire because the two conductors are held firmly next to each other by the plastic insulation.  The fact that the bifilar in this setup will have twice as many turns as either variation on the monofilar is irrelevant.  All that means is that the voltage output will be lower.  You have the choice of load resistor and can compensate.  The important thing is that the geometry will be the same.

The whole intention here is to hopefully give you a fighting chance to see _any_ capacitive effects for different types of real world tests.  Like I have posted many times before it's very unlikely that you will observe any capacitive effects from the bifilar coil because the inter-filar capacitance will be minuscule compared to the inductance.  Also, the capacitance is fleeting and trasient and only exists for perhaps a few microseconds before the "dead short" of the wire in the coil "destroys" it.  As far as the "fantastical" claims go for the bifilar coil go, you can expect to see nothing.

So don't worry, there is no "right" or "wrong" configuration for your coils.  Just make "sensible" coils that are sized in proportion to your spinning rotor magnet.

Good luck and have fun!

MileHigh

MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #522 on: January 09, 2014, 02:32:09 AM »
Conrad:

About getting the bifilar coil to self-resonate to the point where the voltage gets so high that the air starts to ionize:

You will not see the air ionizing effects with coils like this with your current setup.  You don't have the available power source.  However, you could still see similar effects.  For example you could have a small "exciter" coil that sits next to and is magnetically coupled to the bifilar coil.  Then you run a sine wave and sweep the frequency in the small exciter coil and observe the unloaded output of the bifilar coil in your scope.  You may see some peaks in the response of the unloaded bifilar coil.

This all sounds fine but there are problems.  The higher the frequency you put into the exciter coil (always use a sine wave on your function generator) the higher the impedance of the exciter coil.  So you have less and less "push" from the exciter coil as the frequency increases.  One possibility would be to connect your signal generator to an audio amplifier and have the audio amplifier drive the exciter coil.  If you are really lucky you might find a frequency that is a sub-harmonic of the self-resonant frequency of the bifilar coil that is below 20 KHz (within the bandwidth of the audio amplifier) and the voltage on the open-circuited bifilar coil will greatly increase and the air will start to ionize.  The key here is you need power.  The hope is that the audio amplifier has enough power to make the bifilar coil resonate at a very high voltage and you start ionizing the air.  You have to keep in mind that in that clip the guy is using a big powerful electric motor though.

Note it would still be a victory if you got the bifilar coil to resonate in sympathy with the small exciter coil to a very high AC voltage.  Something like this:  You pump 15.35 KHz into the exciter coil and you observe a peak in the response of the open-circuited bifilar coil at 122.8 KHz. (8X the exciter coil frequency).   So you have the exciter coil "ringing the bell" at 15.35 KHz and the bell rings at 122.8 KHz.  So you know that you are exciting the bifilar coil at one-eighth the natural self-resonance of the bifilar coil.

All of these types of experiments are experiments in the frequency domain.  Whenever you do these types of experiments you slowly sweep the exciter frequency from low to high and you observe the response in the device under test.  Normally you never see a sub-harmonic induce the device under test to resonate at it's natural frequency.  Rather, you will simply observe the same frequency at the output of the device under test but with a different amplitude and phase.  So you will have to get really lucky to get a sub-harmonic excitation inducing fundamental resonance in the device under test.

There is an interesting "kluge" for this.  Instead of a sine wave excitation try a square wave excitation.  With a sine wave you are only putting one frequency into the exciter coil.  With a square wave you are putting multiple distinct sine waves into the exciter coil.  One of the higher-frequency components in the square wave might "catch" the bifilar coil at the fundamental or at a sub-harmonic and get it to resonate at a very high amplitude.

http://en.wikipedia.org/wiki/File:Square_wave_frequency_spectrum_animation.gif

MileHigh

P.S.:  I must stress that you are reading educated guesses from me and some reasonable speculation.  I have tons of bench experience but it was a long time ago.  Also, these types of things are not discussed in "real life" in the world of electronics.  Perhaps they are effects that are considered and observed and dealt with in the realm of very high frequency analog radio circuits  (nothing to do with free energy).  I am just guessing because I have no experience there.  In one job I worked next to a radio engineer and observed him working on his bench and only spoke a bit about what he was doing.  So please take my comments about all of these ideas for tests and related stuff with a grain of salt.  Most of the bench type testing for "free energy" you see discussed here and on YouTube is only done in the realm of free energy enthusiasts.

MileHigh

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #523 on: January 09, 2014, 03:01:26 AM »

conradelektro

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Re: Tesla's "COIL FOR ELECTRO-MAGNETS".
« Reply #524 on: January 09, 2014, 11:43:27 AM »

For me, a coil normally has a self capacitance (I prefer using this term instead of the interwire or parasitic capacitance),  represented as a parallel capacitance with the coil itself.  This is what defines the first parallel resonant frequency for a coil when you do not connect any tuning cap to it, just excite the coil in a circuit which adds no any other capacitor to the coil and look for the parallel resonance like this link shows here:
http://www3.telus.net/chemelec/Calculators/Interwire-Coil-Capacitance-Calc.htm   

So I find it a bit unusual that the 'parasitic' capacitance values come out as 174pF and 229pF, while the interwire capacitance values come out as 7 and 44pF.  I will think this over how it could be explained, unless the measuring method for the parasitic capacitance inherently introduces some additional "error".

Could you measure the capacitance between any two wire ends of the bifilar coil? 


@Gyula:

I though that parasitic, self and interwire capacitance are three different things. After some contemplation and looking around in the internet I agree, this is all the same. The "capacitance inherent to the coil" usually depicted and mathematically treated as a parallel capacitance to the coil (inductor) http://sine.ni.com/np/app/main/p/ap/mi/lang/de/pg/1/sn/n17:mi,n21:37/fmid/2914/.

I measured the capacitance between the two wires of my bifilar pancake coil (after opening the connection between the two wires).

It does not matter which ends of the wires are used for the capacitance measurement, the capacitance is 200 pF to 230 pF (varies if I measure with 100 Hz, 1 KHz or 10 KHz).

So it looks like this method http://www.qsl.net/in3otd/inductors.html is correct and that method is may be flawed http://www3.telus.net/chemelec/Calculators/Interwire-Coil-Capacitance-Calc.htm .

I will do some measurements with an "exciter coil" like in this video http://www.youtube.com/watch?v=BrY6Q4JCjXs (you called it "measuring resonance without any tuning cap"). The coil will resonate with the "self capacitance of my scope probe" (which is 85 pf - 115 pF).


@MileHigh:

Thank you for your explanations, it helps.

There are always more questions. Do you think that the core of the coil I want to wind should have a diameter of 25 mm, because the spinning magnet has a diameter of 25 mm? (I wanted to have a core of 10 mm, because I have a Ferrite which would fit.)

I understood that the diameter of the coil should be about the diameter of a fist, but I am now thinking about the diameter of the core (of the hole in the middle of the coil). This core could then be an "air core" or an "iron core" (if I put a bundle of iron wire sticks into it) or a "Ferrite core" (if I put my 10 mm Ferrite rod into it).

I could also make a "rectangular core" of 5 mm x 25 mm, because these are the dimensions of the spinning magnet.

Greetings, Conrad