W4AN wrote:
> Has anyone else done any complex station modelling to see the
> affects of nearby antennas?
I use EZNEC for exactly this purpose -- modeling interaction.
In fact, it's the only thing I use it for, because I am convinced
that the effects of my very irregular ridgetop terrain render most
NEC-generated far-field patterns inaccurate at best, and meaningless
at worst. TA and YT are nice, but they don't integrate NEC modelling,
plus only work on a slice and not a surface.
I've modeled my entire station, including as many nearby metal
objects as possible. Then, I look at the currents flowing on each
conductor to get an idea of the interaction that's happening.
It was exactly this analysis which convinced me to change out all of
my guy wires to Phillystran. Not so much for better yagi patterns, but
for the low band wires and verticals in close proximity. Some of the
low band radiators were affected significantly by the guy wires and tower.
Did the changes I made help? I can't say for certain, but I *feel*
louder; and that's what seems to matter the most around here...
-Kirk K4RO
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