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Re: Secondary Theory (Was Bipolar Coil)-Heretical view

Hi Jim,

> Original Poster: "becyn comunication" <becyn-at-hotmail-dot-com> 
> 
> Terry, Malcolm et all,
> 
>     At the risk of sounding ill informed, I'd like to play Devil's advocate 
> on the 1/4 wave theory. While there is no dispute that lumped parameters 
> "get the job done", perhaps some subtlety has
> been overlooked. Could the discrepancy between the wire length and actual 
> resonant frequency be a function of velocity? Coil geometry
> has a great deal to do with the final outcome for many reasons, not
> the least being distributed capacitance. It sounds reasonable that the
> more "media" the electrons have to slog through, the slower the velocity. 
> Different combinations of LCR will render the pure length
> parameter meaningless, yet it still could be a 1/4 wave phenomena.
> 
>    Now that I've braced myself, go ahead and blast me!

Not at all :)   I am currently exploring the Corum's work further 
with a friend. One thing mentioned in their works is a distinction 
between "series resonance" and "1/4 wave resonance".  For example, 
they say that in a magnifier system, the secondary should be in series
resonance at the the frequency that the resonator is in 1/4 wave 
resonance. They are obviously highlighting a distinction between the 
two modes of operation. We discussed this and came to the conclusion 
that for a 1/4 wave resonator having a defined Rbase at resonance 
when looking into the bottom terminal, it should follow that if one 
feeds in a generator in series with a resistance identical to 
Rbase, a dip should be obtained at which point the resistor should be 
dropping half the generator voltage (i.e dissipating half the output 
power of the generator). At that point, one can immediately look at 
the E field coming off the top to see whether it produces a maximum 
coinciding with this dip or whether the maximum occurs at a 
different frequency. If the dip does occur at a different frequency 
from the e-field maximum, the question then arises: does adding a 
specific Ctop make the two coincide? Can one make a distinction 
between 1/4 wave resonance and series resonance on this basis? 

    It is possible that when the Corums speak of adding terminal 
capacitance to bring the resonator into 1/4 wave resonance they are 
implying that this is the capacitance that makes the wire 1/4 
wavelength long at the frequency at which the resonator ends up. 
Nowhere in their works do they specifically state that however. We 
know that to make the wire meet this condition, terminal capacitance 
has to be added to any resonator within the typical h/d range we 
build. However, it may simply be that they are speaking of adding 
Ctop to bring the coil into resonance at some *desired* frequency. It 
is worth noting that doing this appears to have no noticeable 
influence on output for a given power input in a capacitive discharge 
situation.

     My friend and I are working through their calculations to arrive 
at a design methodology from their standpoint. The going is not easy 
and made even less easy in that I have no worked example from them. 
I am told that there is a worked example in the Tube Coils handbook 
of which I don't have a copy. In the papers I have seen, page after 
page is devoted to analysing resonators etc. retrospectively which is 
not a great help if one wants to design them from scratch. Other 
difficulties include:
- an equation for loss resistance which gives unrealistically high 
ESRs for real coils that in practice appear far better when measured 
using sound measuring techniques
- they resort in the end to the use of the lumped L and C parameters 
which anybody who uses our list "recipe" approach loves (because they
actually work well in practice and we can unerringly calculate them, 
even if they are wrong for various subtle reasons). I cannot 
understand why people who claim these things are wrong resort to 
using them like this. Perhaps I've misunderstood them and done them a 
grave injustice. Time (and experiment) will tell.

    I'll keep the list informed of any progress on these fronts. 
Meantime, any answers to any of the above conundrums welcomed.

Malcolm