In a message dated 99-07-01 11:05:10 EDT, brunet@us.ibm.com writes:
> What does the Rohn catalog show for the guy points for Rohn 25G at 50' at
> various wind speeds? I have a copy of the charts for 45G and it shows 41'
> on
> the tower and 40' out from the base for 70, 90, and 110 mph. The guy
> changes
> from 3/16 to 1/4 above 70 mph.
Do *not* make any inferences from 45G to anything else particularly
25G. They're totally different structures. Rohn recommends two sets of guys
for a 50 foot tower at all wind speeds for 25G.
In Rohn drawings, they typically use 80% as the distance to the guy
anchor but this is only *one* scenario. Anchors can be closer in or further
out with proper engineering depending on what specific site requirements are.
The guy spacing on the tower itself is something that should be done as per
factory specs. The ONLY exception to this is that the Rohnd drawings have the
top set of guys down the tower 5 to 9 feet depending on tower-type to allow
for commercial antenna clearance. For typical ham yagi installations, the
guys can be attached to the top of the tower.
A copy of the Rohn catalog should be one of the first things to get
for anyone even slightly interested in tower construction. The latest
editions (highly revised) are available from http://www.championradio.com.
Again, the LXC Prime Directive is "DO what the manufacturer says". A
copy of the Rohn catalog will help you do that.
Cheers, Steve K7LXC
Champion Radio Products
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|