Cecil,

I decided to take a look at the question you asked below, and I came up
with a really simple modeling experiment.

Set up a simple quarter-wave vertical in EZNEC, resonant at 7 MHz. Run
the source and current functions and save the data. Now change the
frequency to 3.5 MHz and repeat the source and current functions. Do not
scale the antenna or change anything else. I believe most people would
now view this antenna as one-eighth wave at the new frequency, or
perhaps representative of a whip above a loading coil (at 3.5 MHz).

This experiment demonstrates what happens to the "remaining eight feet"
when confronted with the conflict between the "need" for 90 degrees and
the availability of only 45 degrees.

My computer did not blow up, and I suspect yours will survive as well.

Any number of permutations can be tried. Change the length instead of
the frequency, scale up, scale down, and so on. The current always
starts at 1.0, and it always goes to 0.0 at the tip. The reactance and
driving voltage can be awesome, but the current remained unfazed (or is
that unphased?).

This is not a revelation. Antenna books point out that the current in a
short antenna decreases in a straight line, not a sine curve, from the
feed point to the tip. (E.g. Kraus, 2nd Ed. page 216)

Since your traveling wave model seems to be based on a 90 degree
requirement, you may want to consider incorporating this additional
information before submitting your new model for publication.

73,
Gene
W4SZ

(The "eight feet" is taken from your message. In this experiment the
whip length is quite a bit larger, of course. Rescale the entire
experiment if you like.)


Cecil Moore wrote:


Here's an unanswered question: If the loading coil occupies zero
degrees, how can the remaining eight feet of the antenna occupy
the entire 90 electrical degrees? Wouldn't the coil have to
change the frequency for that to happen?