On Sun,3/19/2017 12:29 PM, Douglas Ruz / CO8DM wrote:
We think about the beverages but I have been reading that beverages near the
sea don't work very well.
What matters is the soil conductivity under the Beverage. If the soil
conductivity is high, a Beverage won't work. A few feet is probably too
close.
Take a look at the VE3DO loop, and even an array of them if you have the
space. It's VERY easy to build and rig between a pair of poles. I just
got a pair going and it works as well as my 550 ft
Beverage.http://www.ok1rr.com/index.php/onair/8-qmgr
For 160M, the ideal spacing between a pair is about 350 ft, which is how
mine are rigged. The pair also works pretty well on 80M, but the spacing
is too wide for 80, and half the spacing (5/8 wave) would be better for
80. The pattern of a pair of loops can be steered by phasing them --
that is, change the phase of one relative to the other, either with an
electronic phasing network like those used for noise cancelling, or by
switching in lengths of coax to one of the two loops.
An ongoing study of the array is at k9yc.com/VE3DO.ppt The choice of
ferrite for the transformer is not critical. I used a #43 core and
approximately doubled the number of turns on each winding. For minimum
noise coupling, windings should be on OPPOSITE sides of the core (which
minimizes capacitance between windings), NOT wound on top of each other
(which maximizes capacitive coupling).
73, Jim K9YC
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