You are correct Kurt. I've had great fun reverse engineering old towers
with little historical documentation and stamping them under 222-G.
The same approach can be used on antennas as well.
In an ideal world with unlimited budgets, ham installations would be
designed the same way as cell tower installs -- where the antennas
are considered structural elements and the tower/antenna system is
designed as one united structure.
The TIA-222-G standard uses the phrase "structural antennas." So yes,
ideally a yagi manufacturer would supply a matrix listing its
performance under various heights, wind zones, terrain, environment,
seismic loads, ice, etc., along with the Effective Projected Area
under each of those conditions. There will and should be some
combinations where the manufacturer puts "not recommended."
I'm not aware of any that do that now.
I hate to say it but sooner or later a ham is going to run into this
when they apply for a permit. A sharp-eyed city or county reviewer
who does a strict reading of 222-G can insist on a stamped plan for
the _antenna_. I'll have sympathy for the ham when that happens!
73 Jim K6OK
Kurt K7NV wrote:
>> 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.
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