[TowerTalk] Rotator Choice for Larger Yagi

[K7LXC at aol.com]

>  Is there a better way to determine if a rotator can handle  an antenna 
based
on its size rather than just its wind area? Lots of people  here have
recommended the M2 Orion 2800, which on paper is rated for 35 sqft,  but
when I asked the tower installer who will be putting the antenna up  whether
he thought the Orion could handle the OB17-4, he said that antenna  will
tear an Orion up and strip the gears on the output shaft in short  order.
 
Hiya, Jerry --
 
    I also recommend the Orion IF 1) you use a  different controller 
(preferably the Green Heron - the factory controller is  something only the 
designer could love) and 2) use a different mast clamp  (the factory one has a 
couple of fatal problems),
 
    I've installed dozens of Orions and have  never seen one with gears 
stripped. It uses a worm gear drive so it's kind of  far fetched that the gears 
would be stripped. I do question your installer  though but everyone is 
entitled to their own opinion. 
 
    Rotator ratings are not an exact science. Different  antennas have 
different wind profiles and characteristics. The rotator chapter  in my UP THE 
TOWER book has a table of the static specifications and IMO using  the 
Hy-Gain Effective Moment or the Yaesu K Factor are both reasonable  estimations. 
You'll never get the exact answer you're looking for. My advice? Go  with 
what you've got and it'll work FB.
 
Cheers &GL,
Steve    K7LXC
TOWER TECH