Re: Transformerless Tesla coil

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jolyon Vater Cox by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>

Antonio,
thanks for putting me straight on the series resonant network connected
across L1.
Yes, I can see it now- L1 is connected across two branches of the bridge;
the branches are two series-resonant tuned circuits are connected in
parallel and together they will have half the impedance of a single branch.

Since they are series-resonant each branch will have low impedance and
becauseb there are two of them in parallel, the total impedance will be
lower still.

The only part of the circuit which is parallel resonant is between a and b
(neglecting C3 and C3', the components C2-L2 -L2' -C2' form a continuous
path)
so the only high-impedance points in the circuit are between a and b.

Am I correct?

Jolyon


 ----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, September 26, 2002 2:57 AM
Subject: Re: Transformerless Tesla coil


> Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>
>
> Tesla list wrote:
>
> > Original poster: "Jolyon Vater Cox by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>
>
> > Antonio,
> > Is it not likely that the current drawn by the output network  from the
> > "primary" resonator (L1-C2) would actually be quite small -as the
voltages
> > at the terminals of the two "secondary" resonators are 180 degrees out
of
> > phase
> > so the arms of the "bridge" together will act as a paralell-resonant
tuned
> > circuit
> > exhibiting high dynamic impedance at the resonant frequency?
>
> No. The current from L1-C1 feeds both resonators with identical
> currents. The two branches of the bridge have identical impedances.
>
>                         (=====)a    (=====)b
>                            |           |
>                            L2          L2'
>                            |           |
>     o------+--C1--+----(=) | (=)---(=)-+-(=) <-Influence rings
>            o      |        |
>    PSU    gap     L1       |
>            o      |        |
>     o------+------+--------+---------------o Ground
>
>     o------+--C1--+------+----------+----+
>            o      |      C2         L2'  C3'
>    PSU    gap     L1     +----+     +----+
>            o      |      L2   C3         C2'
>     o------+------+------+----+----------+-o Ground
>
> For perfect balance, C2=C2', C3=C3', and L2=L2'.
> For symmetry in the structure, C2=C3.
> C2=capacitance between the left influence ring and L2/terminal a.
> C3=capacitance between L2/terminal a and ground.
> C3'=capacitance between the right influence ring and L2'/terminal b.
> C2'=capacitance between L2'/terminal b and ground.
> (Ignoring the capacitance between the terminals, assumed small.)
>
> Antonio Carlos M. de Queiroz
>
>
>
>
>