Steve,
I'd arrived at. Does the current really taper
away to zero at the open ends or is that effect swamped by ground
capacitance
when it's only 0.5% of a wavelength above ground?
The RF current at the open end of any wire is the vector sum of incident and
reflected energy. Current "cancels" as that reflection co-efficient is
nominally "-1", whereas voltage doubles, as that reflection co-efficient is
nominally "+1". That is the basic mechanism for a "standing wave".
Specific voltage and/or current distribution is influenced by the antenna
specific environment, but it would generally not be "swamped" by the likes
of ground capacitance, as wire segments "connecting to themselves" presents
a much lower impedance.
Mention of "displacement current" would probably be a red herring .....
73, Bob ZL2CA
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