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Re: chokes (fwd)
---------- Forwarded message ----------
Date: Sun, 24 May 1998 16:13:57 -0700
From: Jim Lux <jimlux-at-earthlink-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: chokes (fwd)
Gary Lau wrote:
. Then a BIG resistor,
> like 500-1.5K, 50-100W from each NST terminal to the main gap. I don't
> know why they dissipate so much power but they do, at least if your main
> cap is well matched to the NST and is mains-resonant to draw maximum
> power.
In a series RC charging system, the amount of energy dissipated in the R is
the same as the energy stored in the C. So, if you have a 450 VA NST
(typical), then you are going to be putting half that in the C and half
into the R, hence 200+ Watts dissipation in the R. The fact that the NST
is really an inductive source actually reduces the dissipation in the R
somewhat, but this should give you the general idea.
Seems to me, it would be better to build a LC low pass network as a filter.
Which is what a choke and cap combination is. The problem is that your
interference source is really broadband (a series of impulses) and it can
excite all sorts of parasitic resonances in the filter components.