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The resonance frequency of a single layer solenoid - DERIVATION

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thermite

Thu Feb 21 2008, 06:52AM

Banned on 02/27/2008
Registered Member #1326 Joined: Sun Feb 17 2008, 11:19PM
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Posts: 49

Finn Hammer wrote ...

I think the work of Paul Nicholson covers your needs:

Cheers, Finn Hammer

Thanks so much. For everyone who was interested in the same questions as myself, I just wanted to bring to your attention the relevance of this site.

But we still need the seminal references. If you go to the
#3 Theory notes
and look at the pdf, it refers back to a paper by
G. Briet.

I wish someone can collect as many electronic papers as possible, who has access to them. I am not going to create 100 miles of environmental pollution to go and xerox these papers. the librarians here are terrible to non-students and city library only have
shelves full of adult books ONLY. We are in post clinton-monica-lewdinsky, bush-moshe-katsa-newt-gingrich america. I hope you understand me with compassionate conservatism. (guys some humor is needed to kill the frustrations of life ... if you understand plz.)

cheers

@goldsphere - what a great site, what a great concept, what great people. Thanks soo mush for refreshing our spirituality.

thermite wrote ...

Finn Hammer wrote ...

I think the work of Paul Nicholson covers your needs:

Cheers, Finn Hammer

One important conclusion that emerged in my mind from the discussion in the "definition" thread and could not write it there due to its premature closure was that there are multiple views of the secondary.

At one level it is an open ended transmission line.

If you envisage a pulse travelling and reflecting in it back and forth and the weakly coupled primary as an excited atom, it is like a laser.

Another point of view is that it is a resonant cavity but magnetically coupled to the excitor.
This magnetic coupling is again different from the electrostatic stimulation of an atom in a laser.

The magnetic coupling gives significant advantage in terms of galvanic isolation for the production of high voltages.

Now to the nature of the transmission line. Here I would like your critique to improve the model.

Before Goldsphere's last reference, I had myself come to the conclusion that secondary is a tranmission line different from the regular coaxial or stripline which supports TEM waves.

The secondary is made up of turns. we do know where a turn begins and ends if we look at a start point. each turn has its characteristic magnetic field which has an axial and transverse component. This is derived in all standard E&M books, and esp easy for far field. but the turns are closely spaced. This means they are fairly strongly coupled though not 100%.

What we have is therefore a longitudinal magnetic wave, just like sound.

At the end no current can flow except when there is corona leakage. Lets worry about the toroidal capacitance later. The t-capacitance would only produce an axial displacement current like the standard radio and TV transmission towers produce a vertically polarized electric wave.

Another view is that each turn with its inductance and capacitance is an oscillator (mass-spring) coupled electrically and magnetically to another turn. Almost like a slinky mass-ful spring .

The only way to get out of this confusion is to look at the published literature. G Breit's paper (long since out of copyright) is needed and others. If someone kindly supplies me with the literature, I intend to do a good service to you by writing a clear digest with full derivations for you that you will really enjoy reading and get satisfaction.

But try to get as many papers as possible please.

Because the waves reflect back and forth regardless the model of the transmission line. they make a standing wave. Then the concept of Voltage Standing Wave Ratio, VSWR becomes relevant.

Is there a probe of electric or magnetic field that can allow visualization of these electric and magnetic standing waves ? For example, liquid crystal temp and some energy absorbing powder to make a paint that will get warm and LC will change color, when painted on the wire on one side (minimally to avoid disturbing it) ? Or some kind of field pickup that does not disturb the coil and is local ?

Are there any scaling equations for the tesla coil so those like me who want to make tiny 4" coils can do so ?

cheers

P.S. plz generously help with the papers as the coil is the simplest mechanical structure and should be studied well.

[Edit: Double post]

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