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Re: PSpice modeling of spark gaps

Malcolm,
Thanks for the reference to "Primary Q - A brain teaser" posting. I'll go
out to
the archives and retrieve the info. I've got to figure this out. The gap is an
area I would really like to understand in every possible detail.
Thanks,
Bart

Tesla List wrote:

> Original Poster: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
>
> Hi Bart,
>
> > Original Poster: "Barton B. Anderson" <mopar-at-uswest-dot-net>
>
> <snip>
>
> > >      The most amazing finding the math revealed was that Q for a
> > > tuned circuit with a gap in it couldn't be quantified as a fixed
> > > value the way it can if there is normal resistance only. The math
> > > showed that Q climbed with voltage and absolute losses increased with
> > > current. The reason for this is that Vgap is not proportional to Igap.
> > > Neither voltage nor current is a fixed quantity but continuously
> > > varying in normal circuit operation.
> > >
> > > Malcolm
> >
> > Yes, the gap is complex and difficult to model these details.  I remember
> when
> > you posted your results sometime ago. It is interesting. I'm not sure I
can
> > grasp Vgap not being proportional to Igap. Even with varying capacitive
> and/or
> > inductive loading in the gap, V and I should remain proportional, unless
> > there's a new physical law I don't know about. If Q climbed with voltage
> then
> > it appears to me the "gap" reacts capacitively in nature and the gap
> > capacitance changes with volts/time as well as with varying current.
> Wouldn't
> > Q then follow Vgap? My thinking here is if Cgap = Igap / (dv/dt) = Q/V.
> >
> > Sorry I didn't reply sooner, I've been in the garage the past couple
nights
> > building a new spark gap.
> >
> > Bart
>
> The gap discharge is an arc discharge which exhibits a negative
> resistance characteristic. You won't get a linear decrement if that
> isn't so. The reason Q climbs with voltage is the essentially fixed
> Vgap conduction voltage becoming a smaller and smaller proportion of
> total primary voltage. I could post my analysis one day if you like.
> It should be in the archives from a year and a bit back. It was
> labelled "Primary Q - A Brain Teaser".
>
> Malcolm