Dear Matt,
It is disappointing that Tesla is used a basis for so many conspiracy
theories and related pseudo science. It makes it very hard to find accurate
information.
As for the frequency and tuning it doesn't concern me much. I just add or
remove windings or capacitors till I get resonance.
Do you have any good accurate papers on the subject you can recommend?
Cheers!
-Wil
Cheers!
-Wil
On 02/11/2014 8:12 AM, "mddeming--- via Tesla" <tesla@xxxxxxxxxx> wrote:
>
> Hi William,
>
>
> Quarter-wave resonance is a myth perpetuated by the fact that some
> nicely-proportioned TCs
> have an amount of wire on the secondary that turns out to be close to 1/4
> wavelength, and
> that a TC behaves, to a first approximation, like a 1/4 wave resonator in
> terms of voltage and
> current distribution. Careful empirical studies of the last 50 years no
> not support the 1/4
> wavelength of wire hypothesis. However, those whose scientific knowledge
> comes from the
> back pages of tabloids and ads for "secret knowledge" still promote this
> "Truth" since for
> them faith always trumps fact.
>
>
> Hope this helps,
>
>
> Matt D.
>
>
> -----Original Message-----
> From: William Howard <snakeprior@xxxxxxxxx>
> To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
> Sent: Sat, Nov 1, 2014 11:01 am
> Subject: Re: [TCML] Technical Tesla Coil Questions
>
>
> Dear Paul,
> Thank you for your concise explanation.
>
> I forgot that adding a topload lowers the resonant frequency of the coil.
> So there is no way to match the topload to the secondary. Tuning is done on
> the primary side.
>
> A follow up question: are the primary and secondary oscillating at the same
> frequency or at a 1/4 wavelength?
>
> I get confused because I often see the 1/4 wave mentioned. JavaTC seems to
> supply numbers for a matched resonance.
>
> Is there a way to get a Tesla Coil to operate at 1/4 wave or do you need to
> build a 3 coil system?
>
> I have been battling to get longer than 30cm arcs from my VTTCs. It's
> mainly due to my impatience and incompetence but hopefully there is a way
> to improve the current system.
>
> I don't have any toroids unfortunately. Will have to get one!
>
> Cheers!
> -Wil
> On 31/10/2014 7:39 PM, "paul" <tcml88@xxxxxxxxxxx> wrote:
>
> >
> > > is the topload acting as a capacitive transmitter?
> > > I mean is it transmitting using a dielectric effect
> > > rather than electromagnetic.
> >
> > The electric field dominates, therefore mostly capacitive
> > coupling to surroundings. Far field is negligible which
> > is why you don't need a transmitting licence.
> >
> > > does the topload turn the secondary into a parallel or
> > > series LC network?
> >
> > The TC is either parallel and series resonant - depends on
> > your viewpoint. Looking between top terminal and ground
> > you see a parallel resonance. Looking into the base of
> > the coil you find a series resonance. Same when you add
> > a topload but with increased C.
> >
> > > could the secondary topload be sufficiently sized to match
> > > the inductance of the secondary?
> >
> > Not sure what you mean by 'match' here? Coil and topload will
> > form a resonator with whatever L and C they happen to have.
> > If you want a particular frequency then you must choose the
> > topload to have the correct C to achieve your target frequency.
> >
> > But usually F is not a design target.
> >
> > The topload protects the top of the coil from high field
> > strengths, and matches the output of the coil to its load
> > (usually a spark loading). These considerations determine
> > the size and shape of topload. That fixes the topload C.
> > In combination with the coil, that determines resonant
> > frequency. Then you design a primary to match that F.
> >
> > > ...Tesla used an elevated capacity. Was this for transmission
> > > purposes
> >
> > Probably the intention was to extend the E-field as far as
> > possible.
> >
> > > ... or could it act as a delay line between the inductor
> > > and capacitor?
> >
> > No significant delay.
> >
> > If the topload is too far above the coil it wont be able to
> > protect the top of the coil. Can consider two toploads, one
> > toroidal just above the coil and another of any shape which
> > can be placed remote from the coil.
> >
> > Formation of long sparks requires short very rapid bursts of
> > charge delivered into the developing streamers. The coil only
> > provides charge slowly (compared with the streamer formation
> > timescale), so the topload needs to act as a charge reservoir.
> > A sphere is the worst possible shape for this - for a given
> > size and voltage a sphere is the shape that stores the least
> > amount of charge. A sphere is also poor for controlling the
> > field around the coil top. Toroids are good in both respects.
> >
> > I'll just add that there is no formula to calculate the ideal
> > topload size/shape to give max spark length for some given
> > power level. Coilers have discovered over the years that
> > large is good, and larger can be even better. But there must
> > be an optimum size - too small and not enough charge stored,
> > too large and not enough E-field to push out the streamers.
> >
> > --
> > Paul Nicholson
> > --
> > _______________________________________________
> > Tesla mailing list
> > Tesla@xxxxxxxxxx
> > http://www.pupman.com/mailman/listinfo/tesla
> >
> _______________________________________________
> Tesla mailing list
> Tesla@xxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
>
>
>
> _______________________________________________
> Tesla mailing list
> Tesla@xxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
>
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla