Re: Wire Length (fwd)

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Original poster: Gerry Reynolds <greynolds@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Sat, 16 Dec 2006 17:12:11 -0700
From: resonance <resonance@xxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Wire Length (fwd)


Yes, I stand corrected.  It was the radius at 0.9 H which would be 1/2 that 
value for the dia.

This would probably work great with a large magnifier type design in which 
the coil was elevated 6-10 ft above ground.

Dr. Resonance
>
> Let me see if I am getting this right.  For any  given wire length and 
> number
> of turns-per-inch there is a unique solonoid  height-to-diameter ratio at
> which maximum inductance occurs, and this H/D  ratio is approximately 
> .9/1.
> Is that correct?
>
> Gary  Peterson


>     Actually, it is the H/R ratio that is  0.9/1.0  H = 0.9 R,  or H = 
> 0.45
> D that gives the  maximum inductance for a solenoid. One can manipulate 
> the
> variables to show  that a given wire length and TPI determine a unique 
> coil size
> using THIS ratio.
>    The problem with a coil of this ratio is the very  high voltage 
> gradient
> (dV/dh) and the very short separation between the topload  and the 
> primary.
>    It can likewise be shown that maximum inductance of  a flat coil occurs
> when the ratio of inner radius to outer radius is  77/165. Here again, the
> length and turns TPI uniquely determine the size once  the ratio is fixed 
> at THIS
> value. Not many coilers use flat secondaries,  and maximizing the 
> inductance
> of a primary would not be an objective, since  you want to keep Ls/Lp high 
> for
> voltage gain, so this is more of a mental  exercise than a practical 
> building
> guide.
>
> Hope this helps.
>
> Matt D.
>
> Matt D.
>
>
>