transmission lines and SWR and fractional wave antennas
 

RE my earlier post starting:
Art, the current distribution along even the shortest (fractional
wavelength), constant OD radiator also is ~sinusoidal. etc

** Posted from http://www.teranews.com**

That was my first (and last) use of Teranews, who took a couple of
days to post it. I had given up on them, and switched to Google to
make the post. Now this duplicate shows up - sorry.

transmission lines and SWR and fractional wave antennas
 

Richard Fry wrote:
But in fact that
"triangular" current distribution is just a very short section of a
sinusoidal waveform.

Yes, for a few degrees around the zero crossing
point, y=Ax+B can be a close approximation.
--
73, Cecil http://www.w5dxp.com

transmission lines and SWR and fractional wave antennas
 

richard Fry wrote:
"Art, the current distribution along even the shortest (fractional
wavelength), constant OD radiator also is sinusoidal, etc."

Yes. One of the first things Maxwell noted of his equations is that they
have the form of equations desceibing wave movements in water.

One of my (new to me) books on electromagnetics supports Art`s use of
Gauss.
Stanley V. Marshall in "Electromagnetic Concepts & Applications" says:
"In most cases, it is much easier to evaluate the scalar field direction
from which we can evaluate the electric field intensity than to find the
electric field intensity directly. In cases of symmetrical charge
distribution, using Gauss`s law to find the electric field intensity is
still the simplest method, if we can find a Gaussian surface that will
allow us to remove the field function from under the integral sign.

There are several ways to solve the same problem. Even if we use
photons, all must give the same answer.

I appologize for disparaging Art`s methods.

Best regards, Richard Harrison, KB5WZI

transmission lines and SWR and fractional wave antennas
 

On Jan 14, 12:08*pm, (Richard Harrison)
wrote:
richard Fry wrote:

"Art, the current distribution along even the shortest (fractional
wavelength), constant OD radiator also is sinusoidal, etc."

Yes. One of the first things Maxwell noted of his equations is that they
have the form of equations desceibing wave movements in water.

One of my (new to me) books on electromagnetics supports Art`s use of
Gauss.
Stanley V. Marshall in "Electromagnetic Concepts & Applications" says:
"In most cases, it is much easier to evaluate the scalar field direction
from which we can evaluate the electric field intensity than to find the
electric field intensity directly. In cases of symmetrical charge
distribution, using Gauss`s law to find the electric field intensity is
still the simplest method, if we can find a Gaussian surface that will
allow us to remove the field function from under the integral sign.

There are several ways to solve the same problem. Even if we use
photons, all must give the same answer.

I appologize for disparaging Art`s methods.

Best regards, Richard Harrison, KB5WZI

Accepted.
Does the book extend the rule of equi;ibrium to helical antennas by
applying cancellation
of the lumped loads provided by this means of construction, which thus
provides the means for smaller antennas?
Regards
Art Unwin KB9MZ.....xg (uk)