Re: DC tesla coil

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Dr. Resonance" <resonance@xxxxxxxxxx>



To achieve the larger inductance, just use a 1 inch x 10 inch long ferrite
type core.  Use 1 inch ID PVC pipe and keep it long so it sticks out beyond
the ferrite core at least 4 inches on each end.  Then, over this pipe, slip
another piece of 1.5 inch pipe and wrap it with some thin mylar, PE, or PP,
and again, let the wrap stick out a bit on each end.

The result is a nice HV choke with an iron core for high relative inductance
and no breakdown problems.

Dr. Resonance


>
>  > The main problem with the setup described at the scopeboy site is if
you
>  > don't run the RSG fast enough, you end up with flaming, trailing arcs
in the
>  > RSG because the charging reactor saturates and stops acting like a
current
>  > limiter, and you have a direct short across your power supply - not
good.
>  > The way to eliminate that problem is to add another set of RSG
stationary
>  > electrodes spaced so when one set is lined up with the rotor
electrodes, the
>  > other set is spaced half way between the rotor electrodes.  The RSG
then is
>  > wired to resonant charge the capacitors through one set of gaps, then
>  > discharge the capacitor into the primary through the other set of
>  > electrodes.  Works wonderfully well, and you can run your RSG as slow
as you
>  > want with no diode popping power arcs.  As a bonus, the charging
reactor
>  > only needs to be around 0.2 Henry, easily achieved with 4 50 mH home
made
>  > air core coils in series to withstand the voltage across it.
>
> An schematic diagram, and pictures of an actual setup, would help. It
> looks
> quite strange to charge the primary capacitor through a RSG, since the
> contacts would have to be kept for long periods (possible, with fixed
> electrodes covering a wide angle). The transformer (NST?) would not like
> to have its output current interrupted by an opening gap.
> 0.2 H is quite a lot of inductance for an air-core coil. It would be
> quite bigger than the average secondary coil...
>
> Antonio Carlos M. de Queiroz
>
>
>