Jorge,
I have a 160m antenna asymmetrical antenna, fed against ground, that goes
from one corner of my 120 ft by 120 ft lot to the opposite corner. It is
held up by a single pole, about 55 ft tall. The pole is closer to the fed
end. The wire going up to the pole makes about a 65 degree angle above the
horizontal; the wire going down to the opposite corner makes an angle of
about 25 degrees below the horizontal (the angles are estimated by eye-they
definitely have not been measured). The far end is about 10 ft off the
ground. In other words an inverted L where the vertical part is not
vertical and the horizontal part is not horizontal. The length is the length
arrived at by many trials and errors that, with a matching capacitor between
the antenna and one inch hardline coax feeder, yielded an SWR of
approximately 1:1 at 1825 mHz. I also use this antenna on 80 m through 10 m
by using an antenna tuner in the shack.
My radials are about one inch deep in the ground and restricted to one
quadrant. They vary in length from 100 ft (along the north and east fence
lines) down to 35 ft (house in the way). Number of radials is probably
about 20 (I really don't remember).
QTH is SE NM. Maximum power is 500 watts. I have 190 countries confirmed
on160 m. I have no idea of the pattern of the 160 m antenna. I am
guessing that it works as well as it does because the maximum radiation
occurs well above ground (and the ground around its feed point is very
cluttered by power lines, houses, trees) and is not straight up (like a low
inverted dipole).
73 Paul W5DM
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