On Thu,3/26/2015 7:56 AM, Marsh Stewart wrote:
I modeled a 40' vertical with 92' of top loading on 1.825MZ using EZNEC+
5.0.66. EZNEC+ 5 uses NEC-2. NEC-2 does not like connections to ground with
Real/High Accuracy ground. So I modeled two (2) 65' radials at 6 inches
above Real/High Accuracy ground.
The pattern looks very good with a deep overhead null.
The major shortcoming of this antenna is not the shape of the pattern or
the match to the rig, it is the fact that it's not very tall and the
radial/counterpoise system is limited. It's not a lot different from
what I had in Chicago. It sort of worked, but not great. BUT -- Mike is
in VE9, so even barefoot, he might even work some EU if conditions are
good.
BTW -- to model this antenna in NEC, I'd forget about modeling the
radials and instead add 10-15 ohms in series with a connection to
Mini-NEC ground.
73, Jim K9YC
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