I am in the process of planning 2 beverages on my property: one on EU
(about 30 degreesfrom here) and one on JA (heading about 325 degrees). I
currently plan them to be 580' long and about 10' off the ground, with the
first and last 20' sloping down to the ground. The feed points will be at
about 1150' elevation, the far ends sloping down to about 1116. Since we
have rocky/caliche soil with relatively low conductivity, I plan on using a
ground rod plus chicken wire screen on the far end, and terminating with a
500 to 700 ohm resistor. My questions are:
(1) Does the 34' drop off help, hurt, or no big deal? Should I try to keep
the wire at a constant elevation by using taller supports or keep a
constant distance from the ground?
(2) I could make the runs longer than 580' by changing the direction on the
EU from 30 degrees to about 15 and the JA from 325 to about 310. I could
get a length of about 700' by doing this. Any major improvement by adding
length? How much "beamwidth" will I have?
(3) I could also lengthen the runs by letting the wires cross each other
about 200' from the feed points. Is this extra length worth the
degradation from the crossing?
(4) The feed points will be about 215' from the shack. I plan to bury the
feed lines to each. I will use "direct bury" type cable, but how sensitive
should I be about losses? Should I use high grade, low loss "Buryflex"
type cable or just anything that can stand the burial and the loss at 1.8
and 3.5 mHz really isn't a big deal?
(5) Since I am inherently lazy, I want to put the feed points close
together and only dig one trench. Is this a problem? Should the feed
points be a certain distance apart to avoid interaction?
(6) At the termination, how big does the chicken wire screen need to be to
be effective?
Please give me the benefit of your experience and/or theoretical analysis
of the above situation.
73 John N5CQ
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