ALL coils are distributed in space. They have a conductor. Therefore
they can be analysed in the same manner as transmission lines.

They ARE transmission lines, no matter what length. They can't help
it!

Program COILINE demonstrates how a simple coil-loaded vertical antenna
can be designed by using classical transmission line mathematics.

Enter length, diameter and number of turns on the coil, the length of
the top rod or whip or wire, and you can examine how the thing behaves
at any frequency. You can design anything from a bottom loaded long
wire to a helical for 160 metres.

Coils can vary between a few turns on an empty toilet roll tube to a 4
feet long, 1 inch diameter, plastic pipe wound with 1000 turns.

You can prune the whip to obtain resonance at a given frequency
without having to go out in the freezing cold back yard.

Discover the velocity factor, nano-seconds per meter, and other
numbers for your particular coil. All will be of interest to the
participants in the interminable civil war still raging on another
thread. Ammunition galore!

Download program COILINE from website below and run immediately. Only
47 kilo-bytes. Its quite entertaining.

By the way, it has just occurred to me, I forgot to include coil Q in
the results. But it hardly matters - there's little to be done with
the number even if you know it.
----
.................................................. ..........
Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
.................................................. ..........