On 2/26/2019 8:03 PM, Tim Duffy wrote:
With a good ground radial system (very important) here at K3LR - the
full size 4 square holds its own - almost 6 dB of gain over ground -
compared to a stack of W6NL Moxons (185 feet over 120 feet). The
vertical 4 square is a VERY good antenna for 40 meter DXing.
Soil quality also matters a lot for vertically polarized antennas, while
it does not matter for horizontal antennas. Radials help verticals ONLY
by minimizing losses in the ground they cover; soil quality strongly
affects the strength of the far field. K3LC wrote an excellent tutorial
on this that was published either in QEX or NCJ something like 10 years
ago.
This might, for example, explain why your analysis of the relative
effectiveness of your 4-square is different from Jeff's. My QTH in the
Santa Cruz Mountains has mostly rocky soil, so horizontally polarized
antennas are the winner on all bands except 160M. They're better on 160
because almost any horizontal dipole that could be rigged for 160M is a
LOW dipole. :) I had one at about 120 ft for several years when I first
moved here, and it rarely beat a Tee vertical with about 80 ft vertical
over on-ground radials, and the vertical was usually MUCH better.
One blessing for 160 verticals at my QTH is that the 160M season
(winter) is our rainy season, and laying on top of that rock is a lot of
"duff," droppings from the trees that act like a big sponge to retain
the rain, temporarily improving soil conductivity. Once we've had a lot
of rain, my signal gets louder on 160M!
73, Jim K9YC
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