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>

would a common-mode choke help here?
I understand many people do not like choke filters any more as there is
evidence that they subject the transformer secondary to high voltage pulses
that as damaging as the RF transients they are supposed to suppress.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, September 22, 2002 5:27 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,
> > 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?
>
> This would fall in the problems of a magnifier and severe insulation
> problems. It's simpler to split C1 in two:
>
>                            (=====)
>                               |
>                               L2
>                               |
>    +  o------+--2C1--+--------+
>              o       |
>  PSU        gap      L1
>              o       |
>    -  o------+--2C1--+--------o Ground
>
> If C1 is an MMC, just split it in two, as the voltage over the two
> capacitors reduces to one half with this connection. The NST may not
> like much this connection, because when the gap fires one half of the
> RF oscillation appears in common mode at both its terminals.
>
> Antonio Carlos M. de Queiroz
>
>
>
>
>