RE: Spark gap voltage transients

To: tesla-at-pupman-dot-com
Subject: RE: Spark gap voltage transients
From: "Malcolm Watts" <malcolm.watts-at-wnp.ac.nz> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Sun, 25 Jul 1999 18:30:40 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Hi Gary, Alwyn,

> Original Poster: "Lau, Gary" <Gary.Lau-at-compaq-dot-com> 

<snip>
> I have also been thinking about primary circuits from a transmission line
> perspective.  No one has, to my knowledge, attempted to match circuit
> impedances between circuit elements and interconnects.  As such, there will
> be signal reflections at impedance discontinuities.  While I doubt there are
> significant performance issues due to this (I could be wrong), it may well
> explain the EMI effects that appear to be due to primary circuit features.
> Consider a primary coil, tapped 15 feet from the open (unterminated) end.
> Imagine the reflections going back and forth there?  Unfortunately my
> knowledge falls short of being able to model and simulate such a distributed
> parameter system of lossy transmission lines, but that would make for some
> interesting simulations.  Does anyone want to chop their primary at the tap
> point and see if EMI is reduced?

I've built several coils, the primaries of which have no extra 
conductor in them. They all exhibit severe spiking.

Malcolm