Serge
It is nice to read what other people have to say but it
should never overide your own inclinations to the point
that you stop experimenting
Patterns are very informative but ground losses and efficiency
are just as important factors, as Cecil's page shows with
his overlapping patterns of a dipole over a vertical.
Using the program that you have ( AO ) you can verify these
things for yourself.
I use the same program and it allowed me to create a rotatable
dipole for the top band so that I was not encombered by ground
losses. True the low dipoles tend to bea cloud warmer, but
because of its higher efficiency it can equal the best of
verticals as Cecil's page shows. After all we are only
interested in a very small portion of the energy that we
radiate and that is the portion used for communication, if the rest
that is not used is used for cloud warming then so be it
You have the best program around, go with your instincts
with respect to ground losses but be sure that you have
enough pulses available for acceptable confirmation.
Enjoy the experimenting
Regards
Art

Roy Lewallen wrote in message ...
That question has been answered several times in this newsgroup. For one
of the most recent answers, go to groups.google.com and find my posting
on July 21, 2003 in the thread " efficiency of horizontal vs vertical
antennas".

Roy Lewallen, W7EL

Serge Stroobandt, ON4BAA wrote:

This conversation is starting to get interesting :-)

INVERTED GROUNDPLANES:
What about using an inverted 1/4wave groundplane in order to avoid ground
losses?
Then you have the high impedance point of the antenna close to the lossy
(low impedance) earth.
Due to the severe mismatch less power will couple into the earth.

The low impedance point (feed point) of the antenna is safely high up in the
(high impedance) air then.