Good day all,
Now that my beverages and vertical are working correctly, I am planning to
install a low dipole for sunset/sunrise. But before, I need to understand the
real interest of that installation.
Different authors are saying that a low dipole (id 30 to 60 feet high) on 160m
can in certain circumstances be better than a vertical during the short period
of sunset/sun rise ducted propagation.
If I compare on NEC2 the patterns of those antennas (a 80 feet T vertical/32
radials and a full size 60 feet high dipole on average ground) , the low dipole
starts to have a significant gain over the vertical (more than 3dB) above 60
degrees and a total supremacy (more than 10dB) above 70 degrees.
Does it mean than for this type of propagation the signal can get out of the
duct nearly vertically ?
This question is for the choice of the orientation of the dipole, because it is
a matter of fact that over 60 degrees the dipole have no more directivity and
it can be interesting to install it in a direction minimizing the 0 degree
neighbors qrm or very local broadcast station.
Gilles, VE2TZT
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