Re: Tesla Research Possibilities
From: Thomas McGahee[SMTP:tom_mcgahee-at-sigmais-dot-com]
Sent: Tuesday, September 16, 1997 8:55 AM
To: Tesla List
Subject: Re: Tesla Research Possibilities
> From: Pete Demoreuille[SMTP:pbd-at-cybernex-dot-net]
> Sent: Monday, September 15, 1997 7:27 PM
> To: tesla-at-pupman-dot-com
> Subject: Tesla Research Possibilities
> All -
> This year I have the opportunity to do independent research
> as a class in school. Being very interested in Physics, Math and
> the like, I hope to be able to do further research into the several
> Coils that I have built. I am hoping that some of you have some
> that you could share with me, or could give me comments on some of
> design ideas that I have listed below. I hope for this to be
> research - hopefully I will be able to enter this project as a
> Westinghouse project - but it must be original and at least
> applicable to the real world - no matter how small.
> I was wondering about several things. Why is the accepted standard
> of turns in the 400-1200 range? Is there a rationale?? Why hasn't
> anyone ever made a coil with many more turns, i.e. 3000+. If
> the coil have a desirable aspect ratio is such a problem, then use
> thinner wire, and to make higher currents possible in the coil you
> use multiple layers wired in parallel. (and does aspect ratio
> matter *within reason* in resonator coils or base fed coils???)
Good questions! The suggestion to keep total number of turns within
the range of 400-1200 is based on the observed behaviour of actual
coils. People HAVE made coils with more than 3,000 turns. And they
been horrible performers. Reasons? Well, inter-turn capacitance is
one thing. As you increase the number of turns the inter-turn
adds up more and more. This capacitance affects the ability of the
to respond to impulses, among other things. Like impulses from the
system when the gap fires. Winding multiple layers connected in
is a useful technique to increase current handling in the coil, but
it also increases the inter-turn capacitance effects. (There are more
actual turns involved). You are trading off increased current for
increased inter-turn cpacitance.
Yes, experiments seem to show that the H/D ratio is an important part
of the mix. It is only one part of the mix, but an important part.
The classical TC is not JUST base fed. The magnifier IS. In the
classical TC the primary/secondary coupling plays more than one role.
Energy gets coupled BOTH ways, and that affects overall efficiency
and limits the maximum output.
> With a secondary with many more turns, wouldn't it be possible to
> greatly increase the pri/sec coupling without having to worry about
> interturn breakdown - because there are so many more turns, the
> interturn voltage rise would be bearable.
Yes, more turns could equate to higher breakdown voltage, BUT it
is not JUST breakdown that gets affected. Operating frequency is
affected. Total inter-turn capacitance is affected.
Increasing the coupling creates a whole bunch of side effects.
This includes the spectrum of the resultant oscillations.
Splitting occurs. Thus some of the energy will not be within
the resonant frequency of interest. It is effectively lost
> Also, relating to efficiency. Has anyone ever tried other primary
> designs? i.e. not just flat and helical, and ones with a constant
> slope, but ones with a constantly increasing slope, in order to
> a more desireable field and completely 'immerse' the coil in the
> making voltage rise occur over the entire coil - not just the
Yes. Read the archives. There is a wealth of info there.
> ** many many questions coming - be warned **
> Has anyone ever done research into why the color of the sparks are
> they are - i.e. purple when they terminate in the air, and
> when striking an object. I know that glass is supposed to give
> spindly sparks - but why?? the rate it discharges at? its higher
> dialectric constant?? What do caps of Barium whateveritis do to
> spark color?? why are caps with a higher dialectric constant less
> efficent when operating at RF?? why do secondary coil forms with
> a thicker wall cause more RF loss??
> Wow. I think I exhaused my questions for the moment -
> THANKS ALOT FOR ANY INPUT!
> Pete Demoreuille, Delbarton School
> ps: one more - what kind of amperage is entering the coil from
> And exactly why does the amperage convert from AMPS at the bottom
> of the coil to potential at the top?? The secondary is for the
> part DC? shouldn't current be constant??
> (last one i promise) :)
gotto go now... have a class to teach.
Hope the discussion stimulates even more thoughts and questions.
Fr. Tom McGahee