[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Fwd: [jlnlabs] TESLA COIL REVISED6
Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com>
It's important to remember that a static Q of 200 will drop to around 20
when the sparks are striking a ground terminal. The dynamic Q factor is
important, not the static Q factor.
I've built a lot of coils since my first in 1962 and high turns (up to a
reasonable limit) wins over high Q factor every time. The preservation of
high-Q is only important in the intial driver (pri-sec) system of a
magnifier type system with a third coil (resonator). Example: Ed Wingates
nice dual coil magnifier system using copper tubing on the secondary of the
driver coil for very high Q factor.
To get maximum output you don't want a zillion harmonics wasting energy.
That's why modern TC's are capped with a large toroid --- they reduce the
oscillations to a favored single frequency and eliminate wasted harmonic
Many classic physics texts have always said a small terminal is desireable
but modern experimenters like Rich Hull, et al, have determined optimum
conditions for a great plasma discharge --- not the highest potential in
Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo WI 53913
> Although I am a newcomer to the list, I respectfully disagree that several
> hundred turn secondaries reduce the gain. I built a 20" dia x 48" L coil
> with about 560 turns of 20G Teflon covered wire. Resistance was only a few
> ohms, compared to the inductive reactance which is quite high. One of the
> equations for Q is "Q = X(subL)/R". If for example the inductive
> is 1K ohms and R is only a few ohms you will have a very high Q like 200!
> my opinion Q is what its all about along with a lot of drive power rich in
> A Tesla secondary impedance could be complex in that it is a lumped
> distribution of inductance and capacitance. However at resonance the total
> reactance is highest and it is the point where capacitive inductance
> inductive reactance.
> Also for what its worth (maybe nothing at all!) Has anyone tried an
> additional resonant coil (or coils) coupled loosly in the proximity of a
> running coil which "should" add to the overall Q due to mutual inductive
> coupling(i.e. multiple tuned circuits interacting with one another). Im
> an expert coil builder but I do have some experience building a fairly
> coil and have worked in electronic most of my life.
> to all
> -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Friday, January 02, 2004 12:48 PM
> To: tesla-at-pupman-dot-com
> Subject: Re: Fwd: [jlnlabs] TESLA COIL REVISED6
> Original poster: Tom Stathes <newphreak_16-at-yahoo-dot-com>
> --- Tesla list <tesla-at-pupman-dot-com> wrote:
> > Original poster: Terry Fritz
> > <teslalist-at-twfpowerelectronics-dot-com>
> > Hi,
> > I am not sure who the original writer is, but...
> > At 07:48 AM 12/30/2003, you wrote:
> > >Note: forwarded message attached.
> > >
> > >
> > >__________________________________
> > >Date: Sat, 27 Dec 2003 06:54:13 -0800
> > >Subject: [jlnlabs] TESLA COIL REVISED
> > >Reply-To: jlnlabs-at-yahoogroups-dot-com
> > >Content-Type: multipart/alternative;
> > >
> > boundary="7sXqLKCsjnyYoY64pxfTPFI2R0ZhKSZJleFSmA1"
> > >Content-Length: 1751
> > >
> > >I have a problem with today's Tesla coils. The way
> > they're built these
> > >days, is with the secondary made with SEVERAL
> > HUNDRED turns of thin
> > >wire, which is WRONG. When Nikola Tesla made his
> > coils, they only had
> > >50 to 100 turns of a THICK wire as the secondary.
> > Tesla used a three coil system while most of today's
> > Tesla coil builder's
> > use two coil systems. They are considerably
> > different machines made for
> > different environments. However, the basic
> > principles are the same.
> > >The problem with hundreds of turns of a thin wire
> > is that they have
> > >many times bigger resistance than Tesla's original
> > coils. This big
> > >resistance increases losses, and so minimizes
> > voltage increase due to
> > >resonance. Thick secondary wire will have small
> > losses which allows the
> > >resonance to build higher voltages.
> > Due to the high voltage, the resistance loss in the
> > secondary is small and
> > not a major energy loss.
> > >Here's how Tesla's Colorado Springs coil was built.
> > Primary were 2
> > >turns of a thick cable, and secondary 100 turns of
> > No. 8 wire with a
> > >diameter of 51 feet. That's 1:50 ratio between
> > primary and secondary.
> > >Input was 50 kV into a .004 mF capacitor which was
> > connected to the
> > >primary coil through a spark gap. It could resonate
> > at frequencies from
> > >45 to 150kHz.
> > His think secondary actually had 17 turns of wire.
> > He had a third coil 12
> > high 6 feet diameter 160 turns of #10. It was a
> > magnifier with a modern
> > example at:
> > http://www.ttr-dot-com/model13.html
> > >Tesla's power-transmission coil patent shows almost
> > the same coil,
> > >except that the diameter was 8 feet, and secondary
> > was wound as a flat
> > >coil (also no. 8 wire), and resonance was around
> > 250kHz, producing 2 to
> > >4 million volts.
> > >
> > >So if Tesla's coil could be reduced from 51' diam.
> > to 8' diam., while
> > >keeping the 1:50 primary/secondary ratio, then it
> > should be no problem
> > >to reduce that coil further to about 1' diameter,
> > using only 50 turns
> > >of a thick wire as a secondary.
> > >
> > >The only problem would be the 50kV input that Tesla
> > used, but even
> > >using only 5kV from a neon transformer should
> > produce 200 to 400kV
> > >using the 1:50 ratio, since 50kV input produced 2-4
> > million volts.
> > See the above model 13 details at www.ttr-dot-com.
> > >Also, using a 1' diam. secondary will reduce its
> > inductance, which
> > >will increase resonant frequency to several MHz.
> > And using a very thick
> > >wire, copper pipe or Litz wire would be needed to
> > reduce high frequency
> > >losses.
> > >
> > >So, using a 1-turn primary and 50-turn secondary on
> > a 1-foot diameter
> > >air-core, should make a TRUE Tesla coil which will
> > have lower losses
> > >and more powerful resonance than today's "Tesla
> > coils". Plus that makes
> > >it much easier to make than winding hundreds of
> > turns.
> > Winding hundreds of turns is not that hard ;-) But
> > most of the losses
> > (40%) go into the spark at the gap. The other
> > system losses due to coil
> > heating and cap losses are very small compared to
> > the spark gap. "Modern"
> > Tesla coils are optimized for spark length given
> > commonly available input
> > power and size requirements.
> > Of course, if one can make a better Tesla coil, just
> > do it!!! :-))
> > Cheers,
> > Terry
> > >Jaro