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,
with regard to powering either the directly -coupled transformerless- or
capacitive-transformer tesla coils from both sides of a centre tap-grounded
HV transformer  as opposed to a single-end grounded HV supply
would making L1 a trifilar wound air-cored balun be any use in fulfilling
this objective?

Jolyon.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, September 18, 2002 2:13 PM
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,
> >
> > Apart from being a bridge isn't the  proposed twin transformerless TC
> > actually a pretty good BALUN -to use the radio terminology- as it has
> > unbalanced input and balanced outputs?
>
> The application is quite different. In this case the transformation
> is from the energy in a charged capacitor into balanced oscillations
> in two terminals. Baluns are basically just transformers.
>
> > Also while it may be more difficult to tune, wouldn't it be more
economic
> > and less complicated  to build than most of the other twin-Tesla coil
> > configurations that have been published -after all, I can foresee twice
as
> > many primary components (2 x L1, 2 x C1), balanced-output HV transformer
and
> > centre-tapped grounding for a twin TC done the other way!
>
> A conventional twin would have a single primary capacitor and two
> complete Tesla transformers, with the phasing of the transformers
> adjusted to result in balanced outputs. In this directly/capacitively
> coupled twin the two primary coils are replaced by a single off-axis
> inductor and two "influence planes".
>
>                          (=====)a    (=====)b
>                             |           |
>                             L2          L2'
>                             |           |
>      o------+--C1--+----(=) | (=)---(=)-+-(=) <-Two influence planes
>             o      |        |
>     PSU    gap     L1       |
>             o      |        |
>      o------+------+--------+---------------o Ground
>
> The construction is really simpler. But this system would probably
> not achieve the performance of a classical twin Tesla coil. Its
> dynamics is the same of a "capacitive transformer" coil, with the
> strong limitation of the compromise between many cycles for complete
> energy transfer and low voltage gain.
>
> An interesting aspect, however, is that this circuit produces
> twice more output voltage than the equivalent capacitive transformer
> coil for the same input voltage.
>
> Antonio Carlos M. de Queiroz
>
>
>
>
>