Re: Transformerless Tesla coil

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

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