The bifilar pancake coil at its resonant frequency

[MileHigh]

MH Solenoids coils and pancake coils have different behavior because their self induction are different , so you simple can not compare in the same perspective when measure a solenoid normal coil or bifilar pancake coil .
About you saying  TheOldScientist's are feeding the coils with a sine wave how you have so sure about that ? Could be a square wave and is for sure . He talk about the resonance frequency coil , and to me is clear that if we feed a pancake bifilar coil  even with a square wave when is in resonance frequency , the output will be a sine wave even ljagged scope traces like you say .
like you told   "Sorry, but I personally have very low confidence in TheOldScientist" i feel exactly the same in relation to you .
What is depreciate is you say He is free energy clickbait when he share some of the best videos explanation that you could find in youtube .
Maybe because comments like yours he close the channel only to a particular subscribers this is clickbait ? I think not .
There you have a jagged scope feed by a square wave .
https://www.youtube.com/watch?v=J1wMalWqa7o

On a fundamental level, solenoid coils and pancake coils are not different.  Their behaviour is fundamentally the same.  There will be observable differences between different solenoid coils and different pancake coils in terms of resonant frequencies and the shape of the magnetic fields around the coils and other parameters, but these are best defined as characteristics and not as real differences.  It's important for experimenters to realize this.  You are suggesting that they can't be compared and their behaviour is different.  What specifically are you talking about?

For TheOldScientist, when you look for a self-resonant frequency for a coil, you must use sine waves and if your scope trace is not displaying a sine wave something is wrong.  If you don't know why you have to use a sine wave you can discuss this with your friends on the forum.  He made a mistake with respect to his resistance reading.  What have you become if you can't even state that someone made a mistake making a resistance measurement?  If you understand how wire resistance works, how could you come to any other possible conclusion?

What you want to do is get past being upset about what I said about the TheOldScientist clip and instead understand why I said what I said and appreciate it and understand it.  My comments were true, valid comments.  If he did the clip differently and did a great job then I would have said that he did a great job.

[synchro1]

synchro1,

If you have a bifilar coil and you measured 1.45mH for any one of the windings out of the two and then you measure 5.81mH for the two windings in series connection as you wrote then there is nothing wrong: you are correct with this.

The problem is not this but as follows:
if you make a single wire coil with the same amount of wire you used for the two bifilar windings  i.e. the DC resistance of this single wire coil would be also 5 Ohm (same wire length and same wire OD like the two windings together have in the bifilar) and the mechanical sizes such as the diameter and the length of this coil would be nicely comparable to that of your bifilar coil,
then what L inductance do you think you would measure for this single wire coil?

Because this is the real question here to answer, right?

The answer is you would measure pretty close to the 5.81mH L value. 

I built two such coils, one with a single wire from say 10m long piece of wire, label it as coil A and then I made a bifilar coil from 2 x 5m long wires guided in parallel and connected the two wires in series as you wrote, label this as coil B. I measured very nearly identical L inductances for coil A and coil B. Back then this comparison was done not only by me but Magluvin and TinselKoala: we demonstrated this and you continuously criticised all 3 of us, often with rude words. Three persons separately cannot have crappy L meters. 

Remember what you wrote in your post #33 above:

"Tesla bifilar coils have twice the inductance of single wire coils of the same gauge and copper weight" 

why I quoted this (though the first part of it is not correct) is that it shows you are aware of the condition: the single wire coil should have the same copper weight as the two windings have in the bifilar coil, hence this should mean the length of the wire used for the single wire coil and the added length of the two windings in the bifilar coil should be equal and of the same wire gauge. 

Please demonstrate the measured L inductance of your single wire coil wound with the conditions above.
It is fine you tested your bifilar coil inductance for the individual windings and for their series connection. This latter nicely justifies that if you double the number of turns you get 4 times the inductance, right?

Gyula

Gyula,

Please take a very close look at Gotoluc's "Self running coil #15":

https://www.youtube.com/watch?v=N8BehANEVUo

[synchro1]

Gyula,

I just wound a single wire coil of the same gauge on an identical bobbin and measured the Ohms and Inductance. The test results show that you're right as regards the air core coils. I could only fit 4 Ohms worth of wire on the bobbin. The inductance was 4.3 mh. The serial bifilar at 5 Ohms delivered  5.81 mh. The ratio is pretty close at 1.162 mh per Ohm for the serial bifilar and 1.05 mh per Ohm for the single wire coil. There's clearly no where near the 100% difference Gotoluc measures with his ferrite toroid coils. nor the twice the magnetic strength my iron nail core serial bifilar demonstrated. The sloppy lash wrap of my single wire coil accounts for the slightly lower inductance to Ohms ratio. I concede that TK's measurements are correct and that his meter is functional.

It appears the ferrite core plays a critical role in the doubling of inductance with this Tesla bifilar connection. Maybe TK can run a ferrite core into his bore holes and make comparison measurements for us to help.

[nelsonrochaa]

On a fundamental level, solenoid coils and pancake coils are not different.  Their behaviour is fundamentally the same.  There will be observable differences between different solenoid coils and different pancake coils in terms of resonant frequencies and the shape of the magnetic fields around the coils and other parameters, but these are best defined as characteristics and not as real differences.  It's important for experimenters to realize this.  You are suggesting that they can't be compared and their behaviour is different.  What specifically are you talking about?

For TheOldScientist, when you look for a self-resonant frequency for a coil, you must use sine waves and if your scope trace is not displaying a sine wave something is wrong.  If you don't know why you have to use a sine wave you can discuss this with your friends on the forum.  He made a mistake with respect to his resistance reading.  What have you become if you can't even state that someone made a mistake making a resistance measurement?  If you understand how wire resistance works, how could you come to any other possible conclusion?

What you want to do is get past being upset about what I said about the TheOldScientist clip and instead understand why I said what I said and appreciate it and understand it.  My comments were true, valid comments.  If he did the clip differently and did a great job then I would have said that he did a great job.

No MH is not my intention become upset about what you said, i just give a opinion in the same coin like when you answer in that mode , but you have the right of don't like their videos or from others for sure  .

About i say that solenoid coils and pancake coils are different i maintain what i said .

A bifilar pancake coil is capable of holding more charge than a single wound coil and that is known .
When this coils are operated at resonance, the distributed capacitance on the bifilar  overcome the counter electromotive force that normal is find in conventional coils .
Seems i really don't know what is resistance need to learn again , but seems to,  that you talk about this particular subject of bifilar pancake coils without any practical experience, but just by heart or based in what you hear.

The topic is "The bifilar pancake coil at its resonant frequency "    and i tell you that is possible match their resonance coil with a square wave where the output will become a sinus wave , and myself are exactly discuss on that perspective .

Did Tesla use a sine wave to feed that type coils ?  i think not  you invented the flat pancake coil ?

It's important for experimenters to realize that they simple can not assume something only because persons like you are not able to view more deeply some of aspects of bifilar pancake coil that are denied .
But persons like you that use the sentence  " carved in stone" to justify something without testing ,for sure will take their stubbornness to their grave stone too.

I already say to you in other occasion but i will repeat myself :
fool is the one who thinks already knows everything closing the "window" to learn and improve their wisdom.

Have a nice day MH

[synchro1]

I wrapped a high perm ferrite rod of 1000, with a bifilar coil, shocked the coil and measured a steady rise in Ohmic coil resistance over 24 hours. A "Mag Amp" effect. I concluded that the bifilar resonance was magnetizing the ferrite core free of charge. This was the theory I used to explain the "Impulse Magnetization" of the iorn nail. I spent a long time explaining this effect in my earlier threads.

I called the "Tesla Coil Builder" bifilar test a parlor trick, because as I revealed, the nails alone without the coils attached to the battery, differed in permanent magnet strength by a factor of 2.

I "Impulse Shocked" both nail core coils, then they sat over night. I noticed the difference the following day, and set about trying to explain the effect. I proposed the electron alignment theory that explains how the bifilar ferrite core resonance actually transmutes the core into a higher isotope. This effect has nothing what-so-ever to do with the kind of power supply to the coil TK is imagining.

This effect is the "Magic" of the bifilar, and Gotoluc's double inductance measurements and self running coil effect tie into it. "Evostars" demonstrates conclusively in his video tests, that the magnetic field of the series bifilar coil in resonance is "Outside the Coil"!