Gentleman,
Far be it from me to take issue with those who more learned than I when it
comes to antenna modeling, theoretical gain analysis, wave patterns,
electromagnetic theory, etc. I leave that to those who really know their
stuff like W8JI, W4RNL, W4ZV, etc.
However, I will take issue with those who might believe that a "3 - DB"
difference between antennas (at the same height and at the same location) in
modeled antenna gain, actually equates to 3DB in a DX contest taking into
account all propagation paths, differing amounts of noise, propagation
fluctuations, etc. Here is where the practical trumps the theoretical, and
personally I believe that whatever works best in the actual contest at a
particular time is all that really matters.
I remember a rather lively discussion in Aruba many years ago with my
friend, Wayne, N7NG, about the differences between two antennas that I was
using at KM1H. Wayne adamantly stated that there was only a 3db difference
between them, I said that under most condx there was a 1-2 S unit difference
between them and made the difference between running and feeling loud vs. S
& P and having guys CQ in my face.
Who was right? Probably neither of us. The truth like always usually lies
somewhere in-between. Wayne was right about a 3-DB theoretical difference
I unfortunately don't remember what the antennas were now - probably a TH6
vs a 4L longboom 20 on a 42' boom - W2PV design), and I was right about
running guys and being loud.
Being loud and running guys was more important in the contest, and I would
have gladly loaded up a rain-gutter if that really would have worked better
than what I was using.
Lesson: Stay flexible and BE PRACTICAL! What works best at your location
for your radio purpose is all that really matters.
Discussions on theory are a great way to learn and to build better antennas
but 3DB is rarely ever 3DB in a contest and gain figures should NEVER be
seen as absolute. Likewise, silly claims of 20DB gain over a 6L yagi do not
make one louder either and will never stand up to rigorous analysis and
study. I think it is better to enjoy building and experimenting with
antennas, not fight about them.
One more thing, using contest results from the 1970's to document the
viability of an antenna in 2001, means nothing. Radio cndx are different,
radios are different, activity level is different, skill level and
competition is different, contest rules are different, technology is
different and operator motivation is different not to mention that we are
all 31 years older (OUCH!) than we were in 1970! If anyone is the same
today as they were 31 years ago, well, that would REALLY be something to
talk about.
73
Bob KQ2M
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