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

to: Terry, Malcolm, all

With the limited time I had available to conduct additional experiments the
coil design seems to evolve to using a very low resistance high Q for the
first 1/5th of the coil, ie, 1/2 inch copper tubing for the first 10 turns
of the lower part of the secondary coil, and then going up with a very large
stranded wire to approx 1/2-2/3 total height, and then using a finer wire
for the upper part of the secondary.  I came to this conclusion when working
with some small magnifier type designs and always fighting the flashover
problem with the tight coupling parameters required for the driver coil
(first pri/sec coils).  A Professor and close friend of mine from Univ. of
Wis. suggested the Sloan approach --- eliminated the problem altogether by
making the first pri an auto-transformer with the first sec coil and using
an extremely hi-Q lower portion to drive the upper portion which produces
the potential multiplication for the driver coil.  This output is then fed
via a large dia. copper feedline over to the magnifier or extra coil.  In
our experiment we ended up with a 50 turn lower copper tubing driver feeding
upward into a 300 turn #6 AWG upper portion.  Potential multiplication was
excellent --- up to 400 kV to drive the magnifier portion and no flashover
to worry about.  The trick to doing this and getting the high level of
coupling required for a magnifier design is to use a very large dia
coilform, ie, in our case, 60 inches in dia.  Then k stays very high as
required for good energy transfer.   This large dia. driver requirement is
why most small size magnifiers don't work very well because they require the
primary to be wound up higher to hit the same k value and the result is lots
of polyethylene to prevent flashover, and then, even with lots of
insulation, there are still creeping sparks and corona that do not produce a
stable longer term design.

If you have a medium to large coil try this experiment.  Remove the sec coil
and place it 8-10 feet away on a suitable insulating stand.  Now tap into
the normal primary coil and feed this to the bottom of the sec coil.  It
does require some retuning and is a bit more difficult as you now have two
taps to more around, but the results are very interesting.  I would ask
anyone on the list to try this with some of their coils -- you will be
amazed at how well this works out.   You can eventually enclosed the pri
with taps into a large box and just feed the output over to your elevated
sec coil.

Regards,

Dr.Resonance


-----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Saturday, May 22, 1999 3:43 AM
Subject: Re: Secondary Theory (Was Bipolar Coil)-Heretical view


>Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
>
>Hi Malcolm,
>
> I managed to think of a few comments... :-))
>
>
>At 11:31 AM 5/21/99 +1200, you wrote:
>>Hi all,
>>        After reading this post and the one from D.C. Cox I've
>>decided to put an idea that I think resolves the 1/4 wave/lumped
>>conflicts to the list for comment.
>>
>>> Original Poster: "B**2" <bensonbd-at-erols-dot-com>
>>>
>>> Hi D. C., Terry, All,
>>>     Are you suggesting the possibility that there are oscillations
>>> among the capacities of the secondary themselves?  Perhaps an energy
>>> loss mechanism scaled with secondary size?
>>> Wouldn't this show up as a deviation from the calculated R, L, C
>>> lumped frequency model?
>>>
>>> I personally think more
>>> investigation should be done regarding the transfer of energy from
>>> turn to
>>> turn as this may be a very significant source of energy transfer along
>>> the
>>> secondary coil.  These effects would also help to explain some of the
>>> rather
>>> weird differences between present theory and practice.
>>>
>>> Food for thought.
>>>
>>> Regards,
>>>
>>> Dr.Resonance
>>
>>I think Dr R. has hit the nail on the head. There is a fundamental
>>difference between helical antennas which the Corums have been
>>modelling the TC on and the lumped circuits which appear to work well
>>for us. I maintain that there is a world of difference between the
>>behaviour of a close wound coil and a highly spaced one with a
>>gradual transition in between as the turn-turn spacing increases. I
>>think our lumped model has a limited domain of validity as does the
>>Corum's model and ours applies to the vast majority of coil designs.
>>The reason is the degree of k between each turn. Looking at it like
>>this one sees in a closewound coil a transmission line with low
>>impedances bridging sections of the line together. k falls off
>>rapidly as the spacing increases and the transmission line picture
>>becomes dominant. I was able to detect subtle but definite
>>differences in numerous measurements between coils whose only
>>differences were turn-turn spacing but with everything else equal
>>including TPI (they were wound to the same pitch with different wire
>>gauges). Additionally, measurements conducted on non-linear wound
>>coils by Dr Rzsesotarski and Terry Fritz also show that Medhurst's
>>self-capacitance equation is not unconditionally true. If this is
>>correct, it explains the discrepancy which Sloan found in his machine
>>as well (I think he used a greatly spaced resonator).
>>
>>    I still have strong reason to believe that the coherence theory
>>of the Corums lacks validity in a standard two coil design There is a
>>simple thought experiment which can be carried out in practice
>>demonstrating an exception to the theory.
>>
>>Malcolm
>><snip>
>>
>
>
>
>Very interesting idea!!!
>
> We must remember the Dr. Tesla's big coil in Colorado Springs WAS spaced
>wound. Where the vast majority of our's are NOT.  Hope we haven't missed
>anything?!?!
>
> I think helical antenna's, like one sees in real use, are running at
>pretty high frequencies compared to their physical dimensions where our TCs
>are very small compared to their operating wavelength.  I don't know enough
>to say much more, but that concerns me about making comparisons.  I think
>I'll be learning more... ;-)  If Malcolm is correct, we may be able to have
>a wide range of transmission line effects to choose from in our future
>designs.  Who knows were that could lead?
>
>There are two questions we should consider:
>
>1. Is it POSSIBLE to make a true 1/4 wave operating Tesla coil??
>
>2. If we could build it, would it be any BETTER??
>
>Sorry...  no answers from me yet...
>
> I originally did work with non-linear coils trying to make the voltage
>along the secondary increase linearly instead of as a sine wave along its
>length.  I think the deference in resonance between the upright and
>inverted measurements is due to how the fields are distributed and not
>transmission line effects.  E-Tesla3 can easily be changed to simulate this
>and compare the Fo results to a coil that has windings distributed as a
>sine function.  It would really be neat if my program could predict Fo
>where Medhurst could not!  In fact, I am putting my feet up on such a coil
>right now!! :-))  Unfortunately I am too busy working on my EMMC cap and
>LTR coil right now (also a resonance current test)...  So, you will just
>have to wait...
>
> Of course, my fiber probes work just as well to determine the phase shift
>on a large pitch space wound coil as they do on the close wound kind...
>Perhaps Malcolm has built his probe by now and he "knows something"????  My
>present coil is 33% space wound though and it doesn't.....
>
>Here is my old test data and Dr. Rzeszotarski's analysis at:
>
>http://www.peakpeak-dot-com/~terryf/tesla/experiments/experiments.html
>(non-linear coil stuff)
>
>to ponder in the mean time...
>
>
> The "coherence theory" not only has problems being proven by "thought"
>experiments but has problems being proven by "real" experiments too!!  I
>think the problem is not disproving it, but finding one shred of evidence
>that supports it...  The Corum's did a lot of neat work.  I have a great
>deal of respect for the great efforts and I wish their ideas worked out
>better than they seem to be at the moment.  Their research and thinking
>were very far ahead of their time...  However, the coherence theory is sort
>of a low point...
>
> Dr. Resonance, could you be more specific about "weird differences between
>present theory and practice"?  Is there some fundamental observation that
>we can't explain right now?  If so, we need to be working on it....
>
> Of course, the neat thing about all this is that we have the technology to
>"put it to the test" right now instead of spending the next ten years
>"wondering" if it is correct.  If others have their equipment going, I
>might sit this one out to do other work.  If not, let me know what tests
>need to be done.  I sort of hate to be the only voice in such matters...
>
>I think it is going to be a busy summer... :-))
>
> Terry
>
>
>
>
>
>