Cecil Moore wrote in message ...
Mark Keith wrote:
As far as the reverse currents Cecil mentions, I'd have to ponder that
a while.

While you are pondering, here is a quote from _Antenna_Theory_, by Balanis.

"Standing wave antennas, such as the dipole, can be analyzed as traveling
wave antennas with waves propagating in opposite directions (forward and
backward) and represented by traveling wave currents 'If' and 'Ib' in
Figure 10.1(a)."

Standing wave antennas necessarily have standing waves caused by forward
waves and reflected waves. Analyze any coil subjected to forward current
and reflected current and you will be forced to agree that the current
at one end of the coil is not the same as the current at the other end
of the coil. W8JI is thinking lumped circuits when he should be thinking
distributed networks. The phase shift through the coil changes the
phase relationship between the forward current and reflected current, so
of course, their superposed value will be different at each end of the coil.

How much though? What would be an average ratio difference you would
be likely to see on a 8 ft center loaded whip? Or lets go one
better...What would be a likely "worse case" scenario? Will this vary
from antenna to antenna? I would think so. I've never said there would
not be a difference. I actually expect a small difference. But I still
don't think it would be a large amount. Will this change in value be
enough to cause large errors in modeling these antennas? It's already
obvious to me that any info I may gleen from these tests will have no
impact on the position of my loading coils, being I already use them
at the optimum heights. Or as close as physically possible anyway. So
any info gleaned from these tests would only be useful from a modeling
aspect. And I'm not in a position to really comment on that too much.
I don't design modeling engines. Is it your opinion that the modeling
we now see with these antennas and coils is quite flawed? It's obvious
Yuri seems to think so. Myself, I really don't know at this point.
I've never worried about it too much. I don't model shorter than 1/4
wave verticals. MK