Re: primary angle

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Sebastiann,

Javatc is using is Paul Nicholsons' Geotc which is a program written 
in javascript for use with html. Geotc is computing the mutual 
inductance of the two coils then simply calcs coupling by 
k=M/sqrt(L1L2). The mutual inductance is where there is some 
complexity. Paul inserted tables from Frederick W. Grovers' 
"Inductance Calculations", 1946. My copy is a 1973 reprint by Dover 
which I am currently going through. The tables used are table 13, 14, 
and 15 where 14 and 15 are auxiliary tables for circles very close or 
very far apart. These tables include factors for Grover's k' squared 
value. As stated in the book "the mutual inductance is expressed in 
closed form in terms of complete elliptic integrals". The circular 
filaments have radii of the two coils as well as the distance apart. 
Paul has programed this portion into Geotc which does all the 
crunching. All I do is "let it crunch" and then write the output to 
the html form.

I'll shoot you the portion that deals with mutual inductance but 
highly recommend reading the book to get a complete understanding. I 
bought my copy at Amazon.com, $35.

Take care,
Bart

Tesla list wrote:

> Original poster: Illicium Verum <sebas@xxxxxxxxxxxxxxxx>
>
>
> Hello Bart,
>
> Would you like to provide me the formula for calculating the 
> coupling? Even tough I like your program, I like to calculate things 
> by hand. Just because I learn more about coupling that way.
>
>
> Kind regards,
>
> Sebastiaan.
>
>
>
>
>
> Thursday, November 17, 2005, 1:15:45 PM, you wrote:
>
>
> > Original poster: "Barton B. Anderson" 
> <<mailto:bartb@xxxxxxxxxxxxxxxx>bartb@xxxxxxxxxxxxxxxx>
>
>
> > Hi Daniel,
>
>
> > The coupling is determined by the proximity of the coils. All primary
>
> > configurations (flat, cone, helix) work fine if geometrically built
>
> > to provide suitable coupling. Flat primary's are easy to build and
>
> > are the least sensitive to build errors (human errors due to not
>
> > thinking everything through). Low angle conical coils are also pretty
>
> > tame. As the angle is increased, the coil may become very sensitive
>
> > to coupling depending on the distance from the secondary. Keep in
>
> > mind that all primary configurations can also be built so that you
>
> > never reach a desired coupling value. These days, it's just easy to
>
> > calc the configuration keeping in mind standoff voltage and coupling.
>
> > I know some primary's are preferred due to cosmetics and is sometimes
>
> > the driving force in the choice.
>
>
> > I like to think of coupling as analogous to sitting in front of a
>
> > campfire. There's a distance at which the heat is "comfortable".
>
> > Anything else is too hot or too cold. This is true for the little guy
>
> > or the big guy. They both have their own "setting".
>
>
> > Take care,
>
> > Bart
>
>
> > Tesla list wrote:
>
>
> >>Original poster: "Langer Giv'r"
>
> >><<mailto:transworldsnowboarding19@xxxxxxxxxxx>transworldsnowboardi 
> ng19@xxxxxxxxxxx>
>
>
> >>Hi, does the angle of the primary affect the coupling?  I have my
>
> >>primary set at 40 degrees to horizontal becuase it was the easyest
>
> >>to wind that way.  What should I do if angle is to high? thanks for input
>
>
> >>Daniel From Canada
>
>
> >>_