RE: new coil

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Lau, Gary" <gary.lau@xxxxxx>

My thinking is that the filter is there to protect the NST, and the
3-ball gap is an absolute voltage limiter applied across the thing we're
trying to protect.  Having the safety gap in parallel with the main gap
seems redundant, since the lower voltage gap will always fire first.

Why then wouldn't the main gap be an equally effective voltage limiter,
making the safety gap redundant?  Good question and I don't have an
excellent answer.  It has been suggested that mechanisms exist that can
generate high voltage transients across the wires between the main gap
and the NST if they're at all long-ish, so that the NST might see a
voltage higher than the main gap.  I personally haven't measured or
studied this, but it's enough for me to realize that I want a clamp as
close as possible to the thing I wish to protect.

Regards, Gary Lau
MA, USA

> Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
>
> Hi Gary,
>
> Thats how I read it also.... and that is how I think it should be
connected.
> ie, safety gap in parallel to the main gap.  Comments??
>
> Gerry R.
>
>
>  > Original poster: "Lau, Gary" <gary.lau@xxxxxx>
>  >
>  > Perhaps I'm reading it wrong, but it appears that in the photos,
the
>  > 3-ball safety gap is not across the NST terminals, but across the
>  > filter's output, essentially in parallel with the main gap?
>  >
>  > Gary Lau
>  > MA, USA
>  >
>  >  > Here is a way "too" beautiful one!!  I wish I could just take
the
>  >  > "pictures" half that good ;-))
>  >  >
>  >  > http://www.peninsulators.org/Tesla/nstfilt1.jpg
>  >  >
>  >  > http://www.peninsulators.org/Tesla/nstfilt2.jpg
>  >  >
>  >  > But just use old bolts or bent wire for the safety gaps.  You
just
>  > want
>  >  > it to arc over if the voltage on the NST starts to go way too
high.