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,

The purpose of the network shown in my diagram was to solve two problems
inherent in  driving a single end-grounded coil from a centre tapped HV
transformer, firstly, to isolate the output resonator from the high voltage
power supply, and secondly, to protect the transformer from damage due to
common mode noise. The split MMC would solve the first problem but would not
solve the latter.

Seen from the ring -to -ground side the network is parallel tuned tank
circuit of L1,L2,C2 and C3
L1 is equal to L2  and C2 is equal to C3. It is only necessary that series
tuned circuit of C1 and L3 be resonant at the same frequency as the parallel
tank.

Also, looking from the ring to ground side if a signal were applied at the
resonant frequency, two equal antiphase signals at the same frequency would
appear at HV1 and HV2 respectively. The resultant signals would be
differential mode not common mode (unless I am mistaken!) The network is
passive so in theory it works the other way too.

On the latter point of the uncertainty of whether both gaps would fire I
have redrawn
the diagram below to show a single gap across both of the HV rails- would
this not ensure
more reliable gap firing?

                     +-----------to influence ring
                     |
                 +---+---+
                 |       |
                 L1     C2
                 |       |
   HV1----+--C1--+       +--L3--+
          |      |       |      |
          |      L2     C3      |
          |      |       |      |
   CT-+  SG1     +---+---+      |
      |   |          |          |
    GND   |        GND          |
          |                     |
   HV2----+---------------------+

Could it possibly work?

Jolyon.


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, September 28, 2002 4:29 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>
> >
> > would this circuit work any better as a "balun" to allow a
> > centre-tapped HV transformer to be used to power either the
> > Transformerless or Capacitive Transformer coils?
> > Would it stop common-mode noise from damaging the transformer?
>
> I'm sorry, but I don't understant what is the purpose of the
> complicated network, and why would it eliminate RF signals
> at the transformer terminals. Anyway, with two spark gaps
> both terminals of the transformer will be grounded while the
> gaps conduct. But how to guarantee that both will conduct?
>
> Antonio Carlos M. de Queiroz
>
>
>
>
>