[TowerTalk] Wind Load Spec Differences Between Tower and Antenna

[K7LXC at aol.com]

>  Would like to be confident my LM-470 can handle a DB36  (17.5 sq ft 
using 
100 MPH EIA-222-C) .
I believe the 4 El SteppIR (9.7 sq  ft) is fine on the WT51
 
>  Usual caveats about crank it down in the wind already  noted. Also, the 
Tashjian specs are for a *new* tower. I don't know the  vintage or 
history of the LM-470 I have. It came with the  property.
 
    What do the current specs say? In the old days -  pre-EIA-222 - 
crank-ups were rated @ 50MPH. Your tower might be that vintage. 
 
    You didn't include enough specifics. What is  your local windspeed 
rating? You can find an older EIA-222 windspeed rating for  all US counties at 
_http://www.championradio.com/county.windspeed.data.html_ 
(http://www.championradio.com/county.windspeed.data.html) .  San Mateo County, CA, is a 70 MPH 
windspeed zone. Not a high wind area (70 MPH  is the minimum windspeed 
rating) but crank-ups have to be treated with much care  wind-wise.     
 
    You could probably get away with it but if you need  to get a building 
permit, forget it.
 
Cheers,
Steve    K7LXC
TOWER TECH -
Professional tower services for hams