Re: Francophones

In article <8i6omj1vidqoch9421207205iajrb0h5ue@4ax.com>,
cd@notformail.com says...

will see what I mean.
 
I still maintain the principal determinants of the impedance are  as I
stated previously. The formulas for line impedance are shown on this
page and the aforementioned determinants are key.
 
https://www.everythingrf.com/rf-calculators/coaxial-cable-calculator
 
 
 

I could not get the calculator to come out for me.  Getting negative
numbers and about 10 times what they should be.


However if you change the Relative Permittivity you will see how much it
will effect the impedance of the coax.  Go from 1 as air and then 2.1 to
2.6 for teflon and other common insulator/dialectric material and see
how much the impedance changes.

I doubt that you have ever actually ran the numbers or you would see the
impedance change as the material is changed.

The main thing is the ratio of the diameters of the cables, but you
still have to account for the material between them just as you will for
a capacitor..


You can often find the Relative Permittivity  tables where capacitors
are.