"Art Unwin" wrote in message
...

The parabala [sic] is based on inter
inductive coupling
of a dipole so the parabola reflects at maximum current amplitude.

Plane wave reflection from a parabola doesn't have a discrete current
maximum, per se. You are not describing an antenna element whose current is
maximum at the feed point, etc, etc.

The helix reflector is not based on
coupling but the true mechanical impact of particles which is vastly
different.

Maybe true, maybe not. Irrelevant either way. No 160m helix antennas.

... it is always best to initial perform the calculation
from first principles to ensure that the formula is applicable
where you intend to use it.

I did that, it was, and I'm grateful to have your support.

"Sal"

On Dec 30, 9:41*pm, "Sal M. Onella"
wrote:
"Art Unwin" wrote in message

...

The parabala [sic] is based on inter
inductive coupling
of a dipole so the parabola reflects at maximum current amplitude.

Plane wave reflection from a parabola doesn't have a discrete current
maximum, per se. *You are not describing an antenna element whose current is
maximum at the feed point, etc, etc.

That was not my intention. I am pointing to the use of a parabola
reflector as used
with a planar design such as a dipole placed at the focal point to
provide the required phase change
for reflection. ala best possible coupling to achiev e desired effect


The helix reflector is not based on
coupling but the true mechanical impact of particles which is vastly
different.

Maybe true, maybe not. *Irrelevant either way. *No 160m helix antennas.
If you review the works of Kraus and written thesis on different types
of helix
design including the addition of multiple studs you will note that
all reflector surface are linear
and where the sheath style reflector provided maximum gain.
Because of the condensed volume of designs based upon equilibrium
top band frequencies as well as broadcast and below frequences are
available
in a rotatable manner for directivity.
By the way my antenna is based on equilibrium
( how many times have I stated that on this newsgroup?)
which ruled out the standard helical design as it is NOT in
equilibrium




... it is always best to initial perform the calculation
from first principles *to ensure that the formula is applicable
where you intend to use it.

I did that, it was, and I'm grateful to have your support.

Sal
I don't think you did that
The parabolic reflector
is a design to be used in concert with planar designs only.
I used a parabolic initially for temporary experimental purposes only
as I did not find any data of it's use. As cup style reflectors have
proven gain figures for NON planar axial radiation radiators that
would seem
the obvious way to go at the moment



"Sal"
Interesting thoughts tho
Regards
Art