Ian, G3SEK wrote:
"Hopefully you will agree that an IDEAL INDUCTANCE does not ever have
different currents at its two terminals and does not radiate either."
Sorry to disappoint you, but adequate demonstration has already shown
different currents in and out of a loading coil. I won`t claim it was an
ideal inductor.
The title: Current in loading coil. EZNEC- helix. This is not about
an ideal inductance.
An inductor, inductance, or retardation coil is used to provide
inductance.
An inductor has a second definition:
"A passive fluidic element which because of fluid inertness, has a
pressure drop that leads flow by essentially 90-degrees." Sounds vaguely
familiar.
Inductance is defined as a "property of a circuit that tends to oppose
any change because of a magnetic field associated with the current
itself. Whenever an electric current changes its value, rises or falls,
in a circuit, its associated magnetic field changes, and when this links
with the conductor itself an emf is induced which tends to oppose the
original current change."
If the purpose is to provide inductance, and the purpose of thiis
inductance is to exhibit Lenz`s law, then an ideal inductor does not
radiate, but I`m not convinced it does not have different currents at
its two ends, as this says nothing about the coil`s quality or
perfection.
After all, self inductance is the production of an oppositely directed
current in reaction to an imposed current.
An ideal coil can very well be arranged not to radiate or couple to the
outside world other than through its terminals. These terminals can face
very different impedances depending on where each is connected in a
circuit with standing waves. That is what confronts the ordinary loading
coil in an antenna circuit.
Best regards, Richard Harrison, KB5WZI
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