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.

[2] Terminate this transmission line with a dummy load - a pure
resistance which matches the line's characteristic impedance.

[3] Drive this transmission line via a suitable RF signal generator or
source, having a known (or carefully measured) output power into
the line's impedance.

[4] Measure the RF power delivered into the line, and the RF power
being dissipated by the dummy load. This could be done via an RF
millivoltmeter, for instance.

[5] Calculate the amount of power being lost in the transmission line.

[6] Replace the solid cylindrical conductors in the transmission line
with tubular conductors of the exact same material - hollow in the
center, but with a wall width of at least 5 skin depths at the
frequency you are using. Make sure that the outer diameter, and
spacing of the tubular conductors matches the OD and spacing of the
solid-conductor version of the line.

[7] Drive this new line, and repeat the measurements and calculate the
loss in this line.

[8] Calculate the cross-sectional area of the solid conductor, and of
the actual conductive portion of the hollow tubular conductor, and
then the ratio between the two.

[9] Calculate the ratio between the power losses in the two types of
transmission line.

[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.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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