Chuck Sudds asks:
> Just *how* badly does continuously grounded guys mess up the antenna
> patterns on 20-15-10 meters?? I seem to recall an article in QST or some
> other publication about 10 years back that stated that most installations
> will suffer only marginal degradation... on the order of 1/4 db or so.
Did I
> misread this or have there been more recent studies?
This may be true for a particular set of circumstances. I don't worry too
much about a little loss in gain. What makes me sweat is the degradation of
the antenna pattern, including skewing, which can make your antenna talk to
things that aren't the dx you are trying to work.
There is software available, that will allow you to explore the affects of
interaction between stacked antennas and guy wires etc.
I am only familiar with K6STI's AO (Antenna Optimizer), and other programs.
W7EL also has one. Both advertise in the Amateur publications. If you
really want to try and figure out what the guys are doing to you, get one
of these programs and model what you have (or plan on having).
73, Kurt
YagiStress - The Ultimate Mechanical Design Software for Yagi's
Visit - http://freeyellow.com/members3/yagistress
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