On 1/27/2014 1:26 PM, Grant Saviers wrote:
I used two resonant elevated radials, about 18" above the sand and 5'
from high tide at TX5D for 20 ->10. That worked super well. Stay
within 1/4WL of the water and it will work. IMO no direct connection
to salt water is needed, but if you do connect, only the top few
inches matter for RF.
The connection to salt water acts as a counterpoise -- that is, it
carries return current. Radials are at least as good, especially if you
can elevate them.
The primary effect of sea water is that it provides a much stronger
reflection of the wavefront, increasing the low angle field strength by
5-10 dB or so as compared to various kinds of ground (the benefit is
greatest for lousy soil). But that improvement only occurs at azimuths
that take off over sea water. Over land, you see the reduced reflection
strength of the soil, whatever it is.
73, Jim K9YC
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