View Single Post
  #11   Report Post  
Old September 8th 09, 07:42 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
external usenet poster
 
First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default The ultimate tilted monopole

On Sep 8, 1:02*pm, Richard Fry wrote:
On Sep 8, 12:30*pm, Art Unwin wrote:

So far you have shown
progress by tipping the radiator where it started to fill the void at
the center of the donut. This alone confirms the idea that another
vector has to be considered outside the arbitrary border


The change in the elevation pattern shape and gains seen in the
"tipped" NEC plot I posted are NOT due to equilibrium, vectors outside
boundaries, shear forces, torque, spin etc.

The change in the pattern of the tipped vertical dipole are due to
changes in the amount and direction of the energy radiated toward the
earth by, and near the antenna, and the net field that results by the
vector addition of that reflection with the energy radiated in a given
direction by the dipole itself.

Suggest you use NEC to model a vertical dipole in free space, at
several physical rotation angles away from plumb. *See if the gain and
shape of the radiation pattern changes (they won't, if your model is
valid).

Also note that the Poynting vector does not take the form of a perfect
sphere for any linear antenna -- only for a (non-existent) isotropic
radiator.

RF


We have now come to the end of my input.
We choose to disagree. I can go along with that
just to get you and others off my back. I will go away
and let all mumble about things between themselves.
I need a vacation this year anyway and the kids are back in school
so it is a good time and the weather is just right.
This month will be momentous at the UN so a seat in the gallery sound
good
We will see.