> > Very often, the real point behind such kind of questions is
> > *where do I place the only antenna I can have, to get
> > the best results in this conditions ?*.
> > 73,
> > Mauri I4JMY
> For a tower of 60 ft or more, it is trivial to add
> a trap dipole or small (2L) tribander at 30 to 40 ft
> to fill in the unavoidable 10 to 50 dB NULLS
> in the vertical plane pattern of a higher Yagi.
While it is nice to have an antenna that compliments the nulls of
another antenna with a nice lobe, there are other worries.
All my life I have used high yagi's, and never have noticed a
problem. While I might not be slamming an S meter at 500 miles,
I'm still almost always first or second through and often beat
stacks of yagis with my single antennas. I've really never heard
anything that I can't work quickly, unless they just aren't working
anyone around my general area of the USA.
I tend to use heights like Pete suggested, up around 100 feet.
My six meter antenna is a pair of 5 element yagis stacked 20 feet
or so apart with a mean height of 140 or 150 feet.
I've found it is much more important NOT to clutter up the tower
with 10 or 20 antennas, or have 3 or 4 towers within 300 feet of
each other where the higher frequency antennas aim through the
lower frequency antennas, than it is to pick a sweet height.
The worse performing stations I recall are those with too many
antenna jammed in a small area.
In hundreds of AB tests on 160 meters, I've found even on 160 a
high wave angle is useless for anything over a few hundred miles.
They only time high angle antennas work at all is when the signals
are so strong no one needs to worry about signal level.
I think it is valid to worry a bit about filling in low angle nulls, but I'd
be far more concerned with too much junk around the antenna or in
front of the antenna.
73, Tom W8JI
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