There was a set of DOS programs around several years back called HamCalc
which included a program to do that calculation. I'm sure they must still
be available on the net.
73 de Terry KK6T
At 02:40 PM 3/13/2002 0600, Red wrote:
>Hi, Steve and all;
>
>ARRL handbooks provide formulas and graphs for calculating inductance and
>designing coils.
>
> From the 1994 handbook:
>
>"The approximate inductance of a single layer aircore coil....
>
>L = d^2 times n^2) ÷ (18 times d + 40 times l)
>
>where:
>L = inductance in microhenrys
>d = coil diameter in inches (measured to outside diameter)
>l = coil length in inches (measured to greatest length)
>n = number of turns
>(d^2 = d squared and n^2 = n squared)
>
>This formula is a close approximation for coils having a length equal to
>or greater than 0.4d."
>
>The handbook presents several graphs and tables to simplify the
>calculations for coils of selected diameters and turns per inch.
>
>Hope this helps.
>
>73 de WOØW
>
>ve6wz_steve wrote:
>
> > I am looking for some advice or references on how to calculate and/or
> measure the inductance of a loading coil. I have been modelling a loaded
> yagi (for 80m) and know the reactance I require for the loading coils,
> and want to design the coils. I have experimented with a coil on a 6 ''
> form and have tried to measure the inductance with my MFJ analyser....the
> MFJ will not measure over 650 ohms reactance. Is there another way to
> either accurately measure the inductance or calculate the winding
> required for "Y" inductance using "X" gauge wire on "X" diameter form? I
> realize experimentation will ultimately be required but I'd like to get
> close on my first design.
> >
> > de steve VE6WZ.
> >
>
>
>
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