At my new location the planned antenna system (one tower first) is a 25m
(cca 75 ft) self supporting steel tower with a 6m mast (3m inside the
tower). The planned antennas OWA 20m/15m duobander (6 el 20m /6 el 15m) @
25m and a HY105CA on the top @ 28m. The tower will stand over a ground
screen of 400 m^2 chicken wire (15cm ~6" underground), which gives a
screen of 20m x 20m. Some radial wires will be connected to the edge of the
scren outwards. The tower will be shunt fed on 80 and 160. For 40m an
elevated wire 4sq is planned to be hung down from catenary ropes coming down
from the tower. A second 105CA will go up at 12m and maybe a second OWA
20/15m at 18m (fixed to NA).
I modelled interaction between the OWA 20/15m and the 105CA with 3m (9ft)
and found it neglectable.
The OWA duobander (NW3Z design from contesting.com) seems to be great
performer.
73 de Zoli HA1AG
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