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Re: The 1500t secondary myth (long)

Original poster: "Jim Lux" <jimlux@xxxxxxxxxxxxx>


----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Thursday, December 02, 2004 7:07 AM
Subject: Re: The 1500t secondary myth (long)


> Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
>
> Hi Ed,
>
> Very interesting.  I fired up my 15KV 60ma 8 inch coil with a 120pps SRSG
a
> couple of weeks ago at the Denver TC meeting and got 67 inch arcs (one
> witnessed a 74 inch arc that I missed seeing).  Tonight I calculated the
> secondary (with 6x24 toroid) impedance to be 47Kohms (so maybe I should
try
> a slightly larger toroid).
>
> I had this thought experiment tonight that might explain the 36Kohm sweet
> spot.  If one lets the secondary be a thevenin voltage source with a
"fixed"
> source voltage,  one would expect that maximum power transfered <

<snip>
> Maybe the optimum point can be determined analytically.
>
> Gerry R.
>

But I think it all depends on a good analytical model of what the "streamer
load" consists of.  While Terry's empirical 220K+1 pF/ft matches between his
coil and simulation well, the real thing is time varying, which throws a
substantial wrench into the analysis works (since the idea of Thevenin
equivalents, etc, is basically a steady state analysis).

If you want to do linear analysis, you might be able to model the streamer
as a transmission line with very slow propagation velocity and fairly high
loss.

Yet another wrench in the analysis works is that the topload inductance
plays some small part in it. The charge on the top load cannot
instantaneously get into the streamer.  However, to a first order, that
effect will be very fast (nanoseconds) compared with the streamer growth,
secondary LC oscillation effects (microseconds).