On Dec 28, 12:36*pm, Richard Fry wrote:
"Art Unwin" wroteThe antenna compendium states that an assumption
is made with MoM programs that an assumption is made that current
in a radiator is sinusoidal where as we all know that the current
degrades in aplitude dependent on radiator length.

_____________

Art, the current distribution along even the shortest fractional
wavelength, constant OD radiator also is ~sinusoidal.

Current always is near zero at the open end of a linear radiator of
every
physical length. The shape of the current wave formed along a very
short
radiator appears to be very close to triangular. *But in fact that
"triangular" current distribution is just a very short section of a
sinusoidal waveform.

N.B. that MoM programs show exactly this for radiators that are very
short
in terms of electrical wavelengths. *This also is proven
mathematically in
the antenna engineering texts of Kraus, Balanis, Johnson & Jasik,
etc.

RF

O.K. have it your way. At the end of a radiator voltage is a maximum
as current is zero
ie the curves of current and current crosses each other. We can then
use the absolute standard
equatiion of E = I R. Using this formula for understanding conditions
at the end of a radiator
we can state that E, I and R equals zero ala a non closed circuit.
Kraus used four travelling waves in his analysis of the helical
antenna an analysis that was not corrobarated by
following examiners or the application of the NEC (MoM) programs where
disturbing differences was never resolved.
You introduce wavelength as if it was a standard without considering
the velocity factor and where a transmission line analogy
does not satisfy a helical antenna because of slow wave created in a
similar way to cavitation as explored by Bernoulle
or by the addition of sharp corners encountered by current flow
As far as what has been proven in text books they are only reflect the
conditions placed on the problem but also assumption of correct theory
applied.
This is why history shows the evolution of science is a series of
broken theories whose value is measured by their resistance to attack
over time.
I would remind you that the metric of time has NOT stopped. But as I
stated earlier you can have it your way without objection from me
Art