The bifilar pancake coil at its resonant frequency

[TinselKoala]

(snip)

You have to understand the mental stress involved in looking at a scope capture and having to envision and reconstruct what you think the circuit might be in your head.  Even a simple circuit can be stressful with multiple unknowns.

(snip)

Here you go, MH, observe and relax.   

http://www.youtube.com/watch?v=nTPfRMe1Fs0

[MileHigh]

Here you go, MH, observe and relax.   

http://www.youtube.com/watch?v=nTPfRMe1Fs0

You have heard of xes on a phone?  That's the closest thing I have seen to xes on a scope!

Meanwhile, the Fifth Column does other dirty things on a phone!

[evostars]

 the tiny little sine ringing after the pulse,  is the resonant frequency of the bifilar pancake coil.
if pulsed at the frequencyof that ringing the voltage rises, it becomes a continuous sine.
with a lot more energy than a few micro joules.

[MileHigh]

the tiny little sine ringing after the pulse,  is the resonant frequency of the bifilar pancake coil.
if pulsed at the frequencyof that ringing the voltage rises, it becomes a continuous sine.
with a lot more energy than a few micro joules.

That's great that you can observe a ring-down with a single pulse from the IGBT.  That's what's known as the "impulse response" from the coil and and that tells you nearly everything you need to know about the coil.  Yes you are going to get a resonant rise in the response from the coil if you hit it with a series of impulses at the self-resonant frequency of the coil, but that's not really giving you any new information.

My recommendation would be to then take your signal generator and "tickle" the coil at the self resonant frequency to find out if the pancake coil is resonating as a series or as a parallel LC resonator.  You absolutely don't need to drive the coil with the 50-ohm output from the signal generator.  I would suggest putting a 200-ohm resistor in series with the signal from the generator, and then try a 500-ohm resistor in series.  Naturally the signal generator has to be set on a sine wave.

You use the 200-ohm resistor (or the 500-ohm resistor) as a current viewing resistor.  So will there be a lot of current flowing through the signal feed to the coil at resonance or will there be almost no current flowing through the signal feed to the coil at resonance?  That is the big question of the hour.

So, if you really wanted to look at the voltage across the in-line resistor then one option is either your signal generator needs to be isolated from the mains or your scope needs to be isolated from the mains.  If you don't have a mains isolation transformer there are many other ways around that issue.  Any thoughts?  For example, who says that you have to isolate the signal generator itself?  Why not just isolate the signal from the signal generator itself and then the 200-ohm resistor and the coil itself will be isolated.

If you do the test and you see current flowing through the signal line at resonance then you should see almost no voltage across the coil itself.  Or if you see almost no current flowing through the signal line you should see a voltage across the coil itself that is the same as the signal generator voltage.  When you first do the test you only want to look at the voltage across the 200-ohm resistor.  You do not want to put a scope probe across the coil itself because that is disturbing the coil.

If you can figure out your isolation issues then the logical test to do is a full frequency sweep to see what's going on.  You may find different resonant modes at different frequencies.  If your setup is working smoothly, you might want to do a sweep with a 1K-ohm series resistor.

This is all an interesting investigation and could be a great example for other bifilar pancake coil enthusiasts.  I don't know if you have the the experience and the bench skills to do all of this.

A disclaimer is that I am just applying my knowledge from way back when and I have never done a test like this.  Somebody else may correct me or suggest something completely different.

Finally, here is what you don't want to hear because of all of the musings that you have been reading from the various players in the free energy cottage industry that have convinced you that "there is another way" and that you know better after reading all of that stuff.  What you don't want to hear is that the magnetic field generated by your series bifilar pancake coil just stores electrical energy in the 3D volume around the coil by stressing the space with a subtended magnetic field.  There is a big "ho hum" from a lot of people about that fact.  If you notice, essentially all of my comments have ignored the magnetic field and I turn slightly green when you talk about the "spirals" and the "vorticies."  The simple fact is that you can analyze the coil without even thinking about the magnetic field at all assuming there are no magnetic field coupling effects in the testing.

So, if we suppose that you find what the resonant mode for the coil is at the observed self-resonant frequency from your impulse testing, and then you do the full frequency sweep to look for any other resonant modes, then where do you go from there?  Or is it a big secret?

MileHigh

[Zephir]

No "antigravity" device has ever been shown to be real, and I've tested quite a few of them myself

And what? I tested the existence of electrons multiple-times - and I never detected any with my devices. This is supposed to serve as an argument?

List of experimental EMDrive results

You are making the claim, it is up to YOU to prove it.

Prove that overunity and antigravity doesn't exist. It's your claim, it is up to YOU to prove it.