In order to estimate what is the real elevation angle (3dB or HPBW) of an
antenna on far field, we should gather quantitative data.
Tom, what you are after with your measurements/observation?>>>
Only which is louder compared to a standard I maintain.
<<<<
If one will intend to use a statistical method to appreciate a phenomenon
then yes, the greater the time span and data quantity, the better results
will be.
But...there is a big trouble with the big time span. The measurement system
should remain unchanged. If one system parameter will change during that
time, everything will be compromised! How to solve an equation with two or
tree or more unknown terms?>>>
Since I have the unchanged references in the comparisons, it doesn't matter
what else changes unless someone changes polarization at the other end, and
no one did that.
<<<<
Te same thing is with the antenna and propagation measurements.
If one
intend to measure the antenna characteristics, only one parameter should
be changed at a time, the other should remain constant. >>>>
Since it is all against an unchanged reference I control and I only wish to
learn which is better in comparison, not much else matters.
<<<<From the above statement, I realize that you were using the "A B" test
(or A B C D etc. - how many antennas you used) for observing what was the
best antenna for a particular QSO (DX, local, whatever). This way, you
cannot say what was the "key factor" making that QSO. The antenna? The state
of the ionosphere? The other side antenna? The ground beneath your or the
other side antenna or other factors in that system.
I'm sorry to say but such data are useless for general or reproducible
conclusions, quantitative or qualitative.
With such data you cannot state that antenna A (B, C, whatsoever) is the
best antenna for DX (or local QSOs). This was true for your local
conditions. Only for your measurement system at that time!>>>
You can say so, but when over a year or more at all hours of propagation, if
one antenna is consistently better I will elect to use that antenna. :-) I
do not care why they are different, or how much they are different. I only
want to statistically know my best option over time.
The antennas exhibit very predictable results over time. The high dipole
broadside is never much better than the vertical, and at sunrise peak a low
and high dipole is frequently better than the vertical. But the low dipole
is here and gone in such a short time and is not that much better, so it was
never worth it. I would never know when to use it, and ten minutes later it
would be back to the vertical anyway.
During severe solar disturbances, when all directivity is gone and signals
are watery, all antennas are randomly equal. The low dipole can work again.
But so can the vertical.
It really comes down to how many antennas I want to have for 5-10 minutes of
exception that I cannot tell. If I want to work within 300 miles, I will
have a low dipole (100-150 feet high). No one has a problem hearing me at
sunrise peak no matter what antenna I use, so I just use the one that almost
90% of the time is better and almost never worse.
73 Tom
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Topband reflector - topband@contesting.com
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