I have not tried a vertical dipole on 40m, but can
report somewhat similar results with a 40m quarter
wave vertical versus a horizontal dipole at about 40'.
The vertical was in the clear and had about 60 radials
- that should lead to over 90% efficiency.
The vertical was consistently 1-2 S-points worse than
the dipole at any distance and in any direction.
Then I moved the vertical so that it is now amid some
trees about 50' from a reasonably sized lake (~12miles
x 0.5mile) - it had previously been about 400' from
the lake. It is now at least the equal of the dipole
at any distance and in any direction, and distinctly
better for DX.
I can sort of understand that the vertical now has a
better ground plane extending over many wavelengths
which presumably improves its performance. I can't
understand why that is still true in February when the
lake is frozen to at least 5' down and ice is a very
poor conductor.
For some reason the XYL does not seem to think that a
whole row of antennas along the edge of the lake would
be beautiful....
73 Roger
VE3ZI
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