Re: Capacitance of a coil

To: tesla-at-pupman-dot-com
Subject: Re: Capacitance of a coil
From: Bert Hickman <bert.hickman-at-aquila-dot-com> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Mon, 18 Jan 1999 12:11:47 -0700
Approved: twf-at-verinet-dot-com

Tesla List wrote:
> 
> Original Poster: Hollmike-at-aol-dot-com
> 
> In a message dated 1/17/99 3:46:55 AM Mountain Standard Time,
tesla-at-pupman-dot-com
> writes:
> 
> > Mike,
> >
> >  The winding length of the coil is not a parameter in this equation??
> >  When I use Medhurst's formula on my 10" coil, I come very close (15.88
> >  pF) to the measured value (based on reverse calculating from Ls and Fo).
> >  However, if I use the above formula, I only get 3.88 pF.
> Bert,
>     Just out of curiosity, what is the H/D of your coil(or the one you
did the
> calc for)?
> If it is about 4, then maybe this expression just needs that factor
included,
> since as I posted earlier, that it was meant for coils with H/D = 1.
> 
> Mike

Mike,

The H/D for my coil is 31/10.25 or 3.02. Didn't catch the part about H/D
~ 1...

-- Bert --