I'm afraid you are hopelessly mixed up.
What on Earth has it got to do with RG58?
As I have already said, using the well known formulae -
Calculate C pF/m
Calculate L uH/m
Insert L and C in Zo = Sqrt(L/C)
and Bingo! Zo = 3243 ohms.
What it has to do with RG58 is as follows:
C = 55.5 / (Ln( 2 * H / D ) - 1) picofarads per meter.
RG58 has 93.5 pF/meter. (from ARRL Antenna Book)
L = Square( N * Pi * D ) / 10 microhenrys per meter.
RG58 has 258 nH/meter. (from Zo=sqrt(L/C) and Zo from ARRL Antenna Book)
TransLine impedance, Zo = Sqrt( L / C ) ohms.
RG58 is sqrt(L/C) = 52.5 Ohms.
Propagation Velocity = 1 / Sqrt( L * C ) metres per second.
Vp = 1/sqrt(L*C) = 203.7 m/s
Take a length of H =1.5 metres of this helix and use it as a short
vertical
antenna above a good ground.
It will resonate as a 1/4-wave vertical at 3.5 MHz.
Using a 1 meter length of RG58, it will resonate at f = 1/(2*pi*sqrt(L*C)) =
32.4 MHz.
Zo = 3243 ohms.
Zo = 52.5 Ohms.
Velocity factor = 0.0701
Velocity factor = 203.6/300 = .68
In other words, Reg, I don't see why I can't apply the same equations to
determine the resonant frequency of a piece of RG58. Are you saying you can
use these equations and I can't? After all, you are implying you can analyze
your distributed coil/transmission line using non-distributed, lumped
components.
If you can explain my error, please do so rather than insulting me by saying
I am hopelessly mixed up.
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