Jim Kelley wrote:
Cecil Moore wrote:
W8JI's mistake was using standing wave current to try
to measure that delay.

It's not at all apparent that that was his mistake.

The description of his test setup is on his web page.
Did he use standing-wave current to try to measure the
delay through a loading-coil? Yes, it is obvious that
he did. He should have loaded the circuit with the
characteristic impedance of his loading coil. That
would have reduced the reflections to the point that
the actual delay could be measured.

Lacking any sort of description of the stimulus or
of the instrument, it's not clear to me what W8JI's test unit is
actually measuring.

Second, show how those measurements are supported by the
underlying principles, and are predicted by the associated
mathematics. Without those things, you may as well go shout
it at cars.

But since W8JI's measurements are NOT "supported by the
underlying principles", by your own assertions, he indeed
seems to be "shouting it at cars" on his web page. I am
merely objecting to a technical absurdity, e.g. a 3 nS
delay through a foot long loading coil. The standing-
wave current phase shift through a coil bears no
relationship to the delay through a coil.
--
73, Cecil http://www.w5dxp.com