Re: Dual layer primaries

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Ed, all,
             I've built and use a number of stacked primaries. For a 
two layer job: if the spacing between the two layers is about 1 tube 
diameter, both layers are the same diameter and all turns are tapped 
in, the inductance you will obtain is typically about 3 to 3.5 times 
the inductance of a single layer. Quiz - any guesses as to the 
geometry of such a primary that gets closest to 4x? (Hint - consider 
inter-turn coupling in a single layer)

Malcolm 
 
On 7 Jul 01, at 13:27, Tesla list wrote:

> Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<evp-at-pacbell-dot-net>
> 
> Tesla list wrote:
> > 
> > Original poster: "Barton B. Anderson by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <tesla123-at-pacbell-dot-net>
> > 
> > Hi Jason,
> > 
> > Tesla list wrote:
> > 
> > > Original poster: "Jason Johnson by way of Terry Fritz
> > <twftesla-at-qwest-dot-net>" <hvjjohnson13-at-hotmail-dot-com>
> > >
> > > Hello,
> > >
> > > Does anyone have any idea as to how to calculate inductance for a two
level
> > > primary? I'm talking about a primary coil that is wound with two layers
> both
> > > going the same direction and seperated by an inch or so, inner turns
> > connected
> > > together, and tapped in two places, one on the bottom half, one on
the top
> > > half. I know that I can't just calc. for one primary and then double it,
> > > because the halves are going to have some mutual inductance,
resulting in a
> > > higher overall inductance than just doubling one of half the size, right?
> > Does
> > > anyone get what I'm talking abut here?
> 
> 	The inductance should be somewhere between twice and four times that of
> a single spiral; two times if they're widely separated and four times if
> they are very closely spaced.
> 
> Ed
> 
> 
> 
>