Cecil Moore wrote:

Tom Donaly wrote:

Not everyone is happy with the term "displacement current." Albert
Shadowitz, in his book _The Electromagnetic Field_, has a chapter
entitled "The So-called Displacement Current." The term isn't in
the index to Feynman's _Lectures on Physics_. (At least I couldn't
find it.) All that is academic to the fact that AC current seems to
be able to make its way through a capacitor with no more opposition
than the capacitive reactance. Fortunately, no one on this
newsgroup has any objection to the way the term is commonly used.


Here's an associated quote from "Electromagnetic Engineering"
by R.W.P King: "an adequate representation of the reactance
of a coil with a nonuniformly distributed current is NOT
POSSIBLE in terms of a coil with a uniform current [a lumped-
element inductance] connected in parallel with a lumped
capacitance."

I don't know what that has to do with displacement current, Cecil,
but if you're worried about it you can just use your coil at a frequency
where you get a more satisfactory current distribution. I made a coil
like you talk about (mine was 5.25 inches long,
27 turns, 6 inches in diameter) and it behaved pretty much like
a coil in parallel with a capacitor up to a few megahertz, at least.
Beyond that, it was a different story.
73,
Tom Donaly, KA6RUH