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Old August 23rd 04, 11:32 PM
Yuri Blanarovich
 
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Hi Yuri,

As Mac said, there are many "its" in the quote. However the vague
combinations do not resolve to different interpretations as you
persist. The extra wire leads to the same conclusion you BOTH
describe and that is Beverage-like antenna characteristics. As that
is a unique consequence of ground's retarding the wavefront, it
necessarily follows that Tom maintains (and directly states) that the
extra wire does NOT interfere with that action. He states why - tight
coupling. He no where states that metallic copper assumes ohmic loss
as the loss is a consequence of proximity to earth. Further, I've
seen no statement from you or Tom that maintains the extra wire
destroys the Beverage-like antenna characteristic, hence there is not
a hair's width difference between you two.

73's
Richard Clark, KB7QHC


First of all, I have not done experiments to compare single wire Beverages vs.
dual wire, with the other wire being laid underneath the Beverage.
I had the problem with statement "the wire below the Beverage is the wire
couples to the lossy media below it so well it becomes very
lossy" as far as I know wire maintains it's conductivity regardless where it is
laid. Perhaps more accurate statement would be that wire laying on the ground
becomes less significant in its contribution to the performance of the above
Beverage.
But because the "ground" wire is connected typically at the termination point
and at the feedpoint to the Beverage system, I am not sure that it can be
"ignored". Some claim this forms the "open wire" parallel system and has
significant effect on the Beverage performance. There is dispute as far signal
arrival angles are concerned, some signals get subjected to wave tilt due to
poor ground, some signals have their own tilt due to propagation and terrain
effects.
To find out the reality, the exact systems should be compared in various
situations. Modeling might not provide fool proof answers due to some programs
having hard time to model reality, that can be confused by varying ground
characteristics along the Beverage.

Yuri, K3BU