Re: Sparklength inquiry

To: tesla-at-pupman-dot-com
Subject: Re: Sparklength inquiry
From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Thu, 24 Sep 1998 17:19:08 -0600
Approved: terryf-at-verinet-dot-com
Hi Greg, all,

> Original Poster: Greg Leyh <lod-at-pacbell-dot-net> 
> 
> > Original Poster: FutureT-at-aol-dot-com
> 
> > I posted the square law suggestion some time ago, based on my
> > results with the sync gap coils in which I obtained 42" sparks using
> > 620 watts, and 64" sparks using 1570 watts.  I was relating input
> > power to spark length.  I then scaled up the spark lengths using the
> > square law, and your 25' spark TC fit well on the curve.  This
> > posting was before I improved the efficiency of my coils, the old
> > figures were:
> >
> Power input  (revised)         spark length      toroid dia (inches)
> > 680 W         620W actual       42"                   20
> > 2100 W       1570W actual       64"                   30
> > 8400 W       6280W             128"                   60
> > 33.6kW        25kW              21'                  120
> > 67kW                            31'                  240
> > 134kW        100kW              42'                  480
> > 538kW        400kW              84'                  960
> > 1.6MW                          168'                 1920
> > ***new**     5.1MW             300'   
> 
> > I noted in my posting above that this chart was created before I
> > improved the efficiency of my coils. I added a new column in the
> > chart above, and plugged in the values for my present efficiency
> > of my coils (see chart).  Using these new values, I show a need
> > for only 5.1MW to develop the 300 foot spark, which by coincidence(?)
> > agrees exactly with your figure.
> > 
> > John Freau
> 
> Here's another correlating datapoint for your curve --
> At the NZ site, Electrum produced a 40 - 45ft ground strike
> (observed 3 times) with 109kVA on the main transformers.  
> There's this one particular plant (called a 'flux' plant?!) 
> that seems to attract strikes, when the wind is right.

Flax actually. Long spiky leaves?
 
> My two coils land pretty close to the square-law curve 
> that is defined by your two coils.
> And Ed's halfwave coil lands fairly close as well, beating 
> the revised curve by about 20%.  But a halfwave coil should
> be more efficient at producing spark length -- since the spark
> channel is supported at both ends, the ends of the spark need
> be only as thick as the base of a single spark half its size.

And also a higher voltage between the terminals (by about SQRT2) due 
to energy sharing. I got the same sort of result for my minicoil twin.

Malcolm

> So with 5 data points that span over 7 octaves of power,
> it would seem that a simple square-law is a good fit.
> 
> Can it be that easy?  Here's where a good survey would
> come in useful. 
> -- 
> 
> 
> -GL
> www.lod-dot-org
> 
> 
> 
>