In a message dated 98-07-31 12:01:29 EDT, you write:
<< Or horizontal polarisation? Has anyone reading this ever put up a
horizontal antenna at sufficient height that the high angle radiation is
suppressed?
I believe that we have to distinguish between take off angle and
polarisation on this band.
de Greg, ZS5K >>
After few hundred miles polarization has minimal effect, it wanders around, it
shows up as QSB. Most important rule (in my book anyway) is to fit the antenna
radiation patter to the prevailing or desired modes of propagation. So antenna
with wider vertical lobe, like quarter to half wave vertical has wider lobe
and covers more situations.
It is waist to try for low angle, when 90% of propagation is happening at
higher angles. Another factor, with higher sunspots angles of prevailing
propagation on all bands increase. (Observed and verified.)
Yuri K3BU, VE3BMV
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