The recent discussions here are all informative from those that actually
know what is going on!
Everyone needs to understand this one principle:
The professionals that design towers are beholden to do that according
to the most recent standard that clearly defines what they do, when they
design a tower.
All of your antenna builders have absolutely no idea of what those
standards are! Few, if any of them, have mechanical engineers capable of
understanding those requirements....they are amateurs building what they
think you will decide you will buy....that is marketing, not engineering!
I have studied and and documented this disconnect for over 30
years......it absolutely drives me nuts!
The bottom line is that none of you can use any of the antenna
manufacturers antenna area ratings with any of your towers, because they
are not determined by the clearly defined standards that your tower
designers use, because there is no real engineering expertise at any
antenna manufacturer that is aware of what the Pro Tower designers do.
And on top of that, few of the antenna suppliers and tower designers
actually define the antenna area measurements their products
service...... are they projected areas, or are they effective areas?
These are all defined in the EIA/TIA 222 spec....I know what they are
for each tower builder, because I have been into their detailed design
analyses. They are usually citing antenna projected areas! What are your
antenna builders citing? Rohn engineers are very clear about what they
are citing!
I have lots of analyses of commercially built amateur antennas, made
from their own manuals, most all of them are simply WRONG, and not the
least bit useful for deciding what can be put on a current
professionally designed tower!
I have no interest in becoming involved with the usual TT pundit
shitfights.
I just feel it is incumbent on me to come around about once every decade
to remind everyone that this is still a huge unresolved problem, just
like it was ~25 years ago, when I first looked into it....
73, Kurt, K7NV
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