The bifilar pancake coil at its resonant frequency

[evostars]

Hi Evostar,
The two compass are static even before i start feed the circuit because the needles are in their normal position .
You could see too, after i approach the magnet they change their position under the strong magnetic field of magnet but  they return to their normal position even far way outside of coil .  At minute 1:18 i put one of compass under the wire that feed the load (bulb) and their position should change  but needle not change in their position .

I will try next week making new video to show that and aluminum foil levitate .

cheers

Indeed I rewatched it. I didnt remember it correctly. my fault.

Usually when I check for the magnetic field with dc, I put 2 amps into the coil (as the magnetic field induction is dependend on the amps, not the volts).

I would love to see that foil video

[TinselKoala]

You don't need anything fancy to levitate or repel plates of non-ferrous metals with AC. Just a Variac plugged into the wall and a suitable heavy electromagnet coil will do it. And you can levitate all kinds of stuff, conductive or not (aluminum foil, paper, styrofoam, plastic balls, etc) with HVDC.

[pomodoro]

Anyone tried making an electromagnet?, Some internet sites claim tesla's bilfilar winding with the same number of turns makes for a much stronger pull, lifting way more paperclips. Since its DC operated it cant have anything to do with resonance or extra capacitance. I'll give it a go soon myself cause you can't trust all the creeps out there,  but if true, what would be the reasoning behind its extra performance with I'm assuming the same current?

[synchro1]

Anyone tried making an electromagnet?, Some internet sites claim tesla's bilfilar winding with the same number of turns makes for a much stronger pull, lifting way more paperclips. Since its DC operated it cant have anything to do with resonance or extra capacitance. I'll give it a go soon myself cause you can't trust all the creeps out there,  but if true, what would be the reasoning behind its extra performance with I'm assuming the same current?

Pomodoro,

Tesla bifilar coils have twice the inductance of single wire coils of the same gauge and copper weight; This means that the bifilar has the potential to generate twice the magnetic field strength at the cost of double the power. Increasing input two times to the single wire coil would melt the insulation, not increase magnetic field strength.

Measuring field strength between the two types of coils with an input less then or equal to half the double strength produces no difference between the magnetic fields.

I performed the two types of coils test with iorn nail cores and paper clips. One nail will generate twice the permanent magnetic field strength if you saturate both coils. The bifilar will pick up twice the paper clips; However, the bifilar coil eats up twice the power. I tried to make sense of this to Conradelectro, Milehigh and Tinselkoala all three of whom stubbornly ran tests of undercharged coils that deflected compass needles the same amount with the same input. I told them hundreds of times to fully charge the bifilar to test for the double strength, but I could never get anyone to pay attention to me. The additional inductance is a product of "Mutual Coupling", like Flynn's "Phanthom Magnet".

https://www.youtube.com/watch?v=9mxtwS2OsaA&t=5s

[TinselKoala]

Back to your old pattern of misrepresenting my work and that of others, I see.

Pomodoro, I encourage you to do your own testing of the claims made by synchro1.

The bifilar will pick up twice the paper clips; However, the bifilar coil eats up twice the power.

Insert ROFL image here.

"eats up" ? You mean that you _fed_ the bifilar coil with twice the power of the monofilar coil in order to get it to pick up more paper clips. You did this by increasing the voltage supplied, which in turn increased the current through the coil. DUH... of COURSE you will get a stronger field in this case.

With the _SAME_ current fed to both coils they will both have the same magnetic field produced and will pick up the same number of paper clips. Of course using iron/steel nails for this moronic test will skew your results because you are magnetizing the nails themselves, and probably also your paper clips.