g'day to all on the reflector
i notice that the preferred beverage model for
eznec v3.0 is :
(1) a single long wire at the proposed height above ground
(the beverage proper)
(2) a pair of wires connected to the far end of the beverage wire, each
90 degrees long and perpendicular to the beverage & parallel to ground
(to simulate termination ground)
(3) a pair of wires connected to the close end of the beverage wire, each
90 degrees long and perpendicular to the beverage & parallel to ground
(to simulate source ground)
(4) a termination load close to the far end of the beverage wire
(5) a source close to the close end of the beverage wire
(6) real/high accuracy ground model
i guess the experts have gone through a long slow process of confirming
that this model is the best achievable with this particular software package
but i can't find detailed justification on the internet. can anyone point me
in the right direction?
my concerns are :
(1) there is no attempt to model the effect of the vertical leads at close
& far ends; given that verticals have an effective height about 10 times
that of the horizontal beverage even a 3 metre vertical lead will impact
the beverage pattern of the order of 30 metres of horizontal wire and must
significantly impact RDFs
(2) the 4 wires used to model the earth connections are significant in
length
and despite the configurations employed, full cancellation would not be
expected
particularly the horizontal polarisation component
i presume that eznec pro v3.0/nec4 would allow full modelling and avoid the
above
limitations, has anyone actually done a comparison? provision for buried
radials
i guess allows full vertical lead ins & terminations to real earth
roll on 1/1/04
73s gd dx de sam dellit vk4zss brisbane
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