> Any idea how close to salt water a vertical dipole array has to be
> to work well? 15-20 ft to the side and 5 ft up close enough?
It's an interesting subject. See "Lesson #7" in the first link below for
some guidance.
http://pages.prodigy.net/k2kw/learning.html
http://www.k2kw.com/verticals/tests.html
The other question I have not found conclusive answers to is "how much
distance of saltwater is needed to establish the desired low take-off angle
(TOA)?" The intermediate and long-distance conductivity and geography
fields set up the TOA. But how much body of saltwater is needed to get the
TOA of a vertical down to 1 or 2 degrees of elevation?
For example, consider placement of a 20m vertical dipole at a QTH located at
the southern edge of a saltwater bay in the U.S. (e.g., Tampa Bay). Let's
say the bay's distance from the QTH to the northern edge of the bay is 5 km
on a zero degree bearing. North of the bay's edge, soil extends
indefinitely. From that QTH, can one expect a near zero degree TOA into
deep Asia on short-path? At some point, diminishing returns sets in once
the TOA is established and no further separation of saltwater makes a
difference. It would be nice to have a formula that computes that final
distance as a function of operating wavelength.
Paul, W9AC
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