Contrary current flow within a radiator
 

Dave Platt wrote:
In article ,
Michael Coslo wrote:

Warning - dilletente alert! Maybe even worth an embarrassing dolt cringe

This question may have been asked before, but is there a physical
experiment that is good for verifying skin effect?

Here's one, fairly simple in principle although I imagine it would
require care in the implementation in order to prevent measurement
error due to other effects.

[1] Construct a balanced transmission line using a pair of solid
cylindrical conductors, having a known characteristic impedance.

experiment description

[10] Compare these two ratios.

You could in principle do a similar test by making two dipoles out of
solid and tubular elements, driving them with identical signals, and
measuring the field strength. I suspect this test would be harder to
do reliabily.

In either case, what you ought to be able to demonstrate, is that two
transmission lines (one solid-conductor , the other hollow-conductor,
but otherwise identical) which are long enough to exhibit substantial
losses (e.g. 3 dB or 50% of the input power) would have near-identical
losses, even though the amount of conductive material in the
hollow-conductor line is less than 10% that of that in the
solid-conductor line.

This would be good evidence that only the outer perimeter of the
solid conductors was carrying a significant amount of current, since
"removing the center" doesn't decrease the loss.



That's a whole lot too complex. What about measuring the AC resistance
of 3 or 4 parallel wires arranged in a triangle or square, and then
changing the space between the wires. (As is done, say, for HV
transmission lines.. ) Exactly the same effect.