Jim Kelley wrote:

Cecil Moore wrote:
Jim, did you fail to notice that arc-cos(0.95) = 18.2 degrees?

No. But I have failed to notice any explanation for it other than you
and Yuri have provided.

Assuming the forward current and reflected current are in phase
at the feedpoint, the 5% reduction in net current at the other
end of the coil appears to be because the forward current and
reflected current are not in zero phase at that point. The phase
of the forward and reflected currents are changing in a predictable
manner but the phase of their sum, the net current, doesn't change
much if they are in the ballpark of the same magnitudes. I think Roy
measured that net current phase.
--
73, Cecil, W5DXP