[TowerTalk] Questions on tower guying, brackets, etc.

[Nat Davis]

Last fall, I erected a 30' Rohn 25 tower and bracketed it to my house attic 
about 15' above the ground.  That bracket is very solid and tied to my 
house similar to the way the Aug. 96 QST "how to article" 
suggested.  Support from towertalk was really a help last summer.  I need 
more help now... [why do I seem to wait until just before contest season to 
start these projects??]

I want to add another tower section to bring the overall tower height to 
40'.  I can not go any higher than 40' on my small house lot without 
violating zoning setback requirements...  With a modest mast, my antenna 
(hoping to upgrade to a Force 12 C3S or C4S) will be some 45' off the ground.

After reviewing the self-supporting and bracketed tower information in the 
Rohn catalog, I feel that I must add guy wires to the top of the tower -- 
25' of tower above the bracket is just a little wobbly for my taste and 
antenna wind load (am in a county rated at 70 MPH).  Here is where I need 
your collective opinions:

1.	In the past, Rohn has described attaching guy wires directly to/around 
tower legs at the cross bracing joints. Rohn has dropped this method from 
their current catalog, however.  The ARRL antenna book still shows this as 
a way to attach guys.  For my tower size and configuration, would this work 
OK or should I spend the $$ and use the guy bracket assembly?

2.	Guy anchors:  I would prefer to use screw-in anchors (vs. buried 
concrete anchors) and I have seen lots of discussion on them (pro and con) 
in the archives.  The "stock" Rohn anchors seem too weak with their 2,500 
pound pullout rating.  From the AB Chance product line, I was considering 
their model 6346 -- 66" long with 6" screw and galvanized.  It has a 
pullout rating of 4,500 pounds -- more than the breaking strength of the 
3/16 EHS.  These anchors are a little more than 2x the price of the model 
604s that are only 48" long, do not appear to be galvanized, and have a 
pullout rating of 4,000 pounds.   Does anyone have experience with either 
model or can suggest others?  Are the 6346s overkill?  Would the 604s be OK 
for my installation?  If they are not galvanized, should I be worried about 
them "rusting away to nothing" over time?

3.	Just looked at my ruler and 3/16" diameter cable looks darned small 
!!!!!  :-)

Thanks for any suggestions you can give me.

Nat Davis
N4EL


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