# Re: helical cap

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Hello Wells, Bryan, Malcom, all

Now, I AM thoroughly confused. I thought Wells was looking
for the CONICAL inductance equation, which would be:
(please use courier font to view picture)

/\
--  o                          /    o
|   o                        /    o
|    o   N turns            /    o
o                 Z  /    o
h      o                  /    o   /
o                /    o   /
|        o              /    o   /  Angle = X
|         o             \   o   /
--          o               o    ------------
|
|   w   |   R   |
|
|<--  W  -->|
Center | Line

Z = Coil Width (hypotenuse length)
X = Angle of Cone
h = Z*sin(X)  Effective vertical Height
w = Z*cos(X)  Effective horizontal Width
W = R + w/2   Average horizontal Radius

L1 = W^2*N^2/(9*W+10*h)  (Vertical Inductance Component)

L2 = W^2*N^2/(8*W+11*w)  (Horizontal Inductance Component)

L = SQRT[(L1*Sin(X))^2 + (L2*cos(X))^2]

And for the guys, who work it backwards (like me), here is
the equation that gives the number of turns for a specific
inductance value. Very special thanks go to JIM MONTE, who
re-wired the equation for me (I had tried to re-wire it, but it only
resulted in "garbage in, garbage out") (:o))

N = sqrt(L) /(W * ((sin(X)/(9*W+10*h))^2 + (cos(X)/(8*W+11*w))^2 )^0.25)

>> still trying to find the actual equation. It seems to me
>> that somebody has it posted on thier web site.
>>
>> Bryan Kaufman
>
>I think it should be (r^2 * n^2)/(8a + 10h + 11r) where r = mean
>
>?
>Malcolm
>

Hope this helped and was what your were looking for.

?????????????????????

Coiler greets from germany,
Reinhard

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