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Re: That secondary behaviour, E-Tesla5, and Corum's thing...



Tesla List wrote:
 
> Original Poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>

>...

> It appears that several people accept that multiply resonances or harmonics
> occur but are unable to give a  explanation with a lumped model. Terry and
> his artist are on the verge of  grasping the  transmission line theory.
> They recognise the problem with the harmonics and have given a technical
> justification for how such harmonics may be supported and they still cling
> to the erroneous phase issue. I believe the problem at least for Terry is
> that it is difficult to accept that signals can not instantly propagated
> down the coil. This is difficult to accept.  For me it was helped by seeing
> it on the scope so check it out Terry you have all the equipment.  The
> artist and or Terry have suggested that coil is a series of parallel tuned
> circuit that can resonate at different frequencies I don't see how it can do
> that.  But you are getting close just add the capacitance to ground and a
> bit of coupling between the coils and you will have a good model . Plug it
> in to Microsim or spice and see how it works, instant transmission no,
> standing waves yes. If you want I will try and convert one of your coils in
> to a 10 element model.  It should be good for the fundamental and third
> harmonic. May also be able to prove that the turn to turn capacitance is
> insignificant which will allow you to use a standard L and C model  Then
> hopefully I want have to right an other long post on this subject.

A more correct model would be to add to the drawing that Terry made 
capacitors to ground from the junctions of the LC elements. In this
way the model has enough parameters to  model the coil more precisely.
A simple TEM transmission line, as proposed by the Corums (and a known
model for more than 100 years, I repeat), does not take everything into
account. It doesn't consider the mutual inductance between the turns,
nor the turn-to-turn capacitance, nor the variation of the capacitance
to ground with the length of a vertical coil, nor the effect of the
ends of the coil. This can easily verified by measuring the frequencies 
of the high-order resonances in a coil without topload, that are not
exactly in the expected 1:3:5:7:... relation (or by looking at those
100 years old texts, where all this is mentioned...).
Lumped models can predict the behavior of the coil up to the order
of the lumped circuit: With just one LC tank we have just one
resonance. With two tanks, two resonances, and so on. The models
can be obtained directly from approximations of a transmission line
(repeating all the imprecisions and adding more), or from measurements.
The calculations are a bit complex, but standard circuit theory.
 
Antonio Carlos M. de Queiroz