For years I have settled for an 80M dipole 60' up.
My particular interest is to target EU. According to YT arrival angle
data, most of the action is in the 12 to 20 degree range and also in
the 2 to 8 degree range.
I've been through a slew of calculations in EZNEC and found it very
difficult to make much improvement using vertical type antennas. It
appears that over average type ground, one needs at least 3 phased
verticals to equal this crummy dipole. I guess it is the ground
reflection effect that the dipole benefits from which is hard to
overcome. It seems that one would be better off trying to raise the
dipole to 100'+ than mess around with vertical arrays. It appears
that the cost could actually be lower. Alternatively, a two-wire
horizontal array might be a better bet. One could almost certainly
pick up 2-3 db even with a sloppy wire implementation.
I really wonder how the 4 sq arrays achieve the benefits guys claim
for them. Alternatively, the YTAD arrival angles can't be the sole
measure for design.
On another issue, trying to lower the angle of radiation from a 160M
inverted L. I did a bunch of sensitivity studies from 40' vertical
wire height to 110' vertical wire heights. This managed to lower the
lobe only 2 degrees. Conclusion: Messing around with the height of
the vertical radiator won't help much. So what's left? Here
horizontal wire choices are nil.
It seems that on these lower frequency bands, one quickly hits a wall
and obtaining significant improvments requires draconian efforts.
Then there is the other solution to stronger signals some guys
employ....
73 de Brian/K3KO
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