N6KJ"
>I'll be happy with a model of the 3 element SteppIR tuned to 28MHz.
This isn't the first time I've used EZNEC, but typically I start with
something similar to what I want then just modify as necessary. I
didn't find a 3 element yagi example in my batch of models from the
ARRL Antenna Book. I may have missed it if it is there.
There is a standard model of a 3 elementNBS Yagi for 50 MHz
included with EZNEC. You
could re-scale it for 28 MHz, but...
EZNEC displays the pattern in free space,
which is not very useful. You really need to
look at vertical patterns over ground to see
the effect of ground reflection vs antenna
height using a program like YT (included with
the 18th and 19th editions of ARRL's Antenna
Book) or its successor HFTA in the 20th edition.
The vertical pattern over real ground differs
dramatically depending on height above ground.
73, Bill W4ZV
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