Chet:
I have in one of my towers (the biggest, 135ft) 3 elevated guy anchors, was
the only way to put this tower, i have several buildings in the proporty, is a
city lot, other things like trees and some fences give not much clearence for
the guys.
here is my case, i need some good and strong anchor , my area is very
popular for earthquakes the separation less than 80% from the tower base. i
use pipes 6.5 inch diameter 1/4 inche wall . 17 and 15 ft long each., i
put 2 pipe welded at the tallest anchor pipe (17), 5 ft deep in a big hole,
in a inverted mushroom shape, 2 cubic meter at least in each hole of concrete ,
several rebars welded in the pipe to give structural strengt to the concrete ,
this works in 2 anchors, in the 3rd i use a big H beam , 10x18x10 inches 7/16
inch wall 12 ft long reinforced with a smaller 7 ft H and 1.5 inch
steel bar to gives strengt just in case, to this i add another 2 cubical
meters of concrete 5ft deep, this beam was not at 90 deg, was installed at 75
degrees (contrary to the pull action of the guys)
i hope to be clear in my installation , this have several years and have no
problems , i sleep well in bad weather. all the pipes are concrete filled , a
single piple will bend tensioning the wires, double gives good strength one
behind the other , other thing i don't mention , i joint my anchor concrete
base to the wall basement , adding extra weight and support in case the
ground gets very wet (extreme case)
i think the over kill is the best to rest and sleep well
On 19 Oct 2005 16:44 PDT you wrote:
>
>
> After watching the PVRC contesting tape by W3LPL I decide to take " Take off
> angle" seriously. I recently put up a C4 at 45 feet below my C31XR at 90
> feet. . I chose 45 feet because........that gave me the most clearance for
> the C4 to turn underneath the top guy at 70 feet.... and using the EYEBALL
> method...it ALMOST clears. Measured it today and we need another 20 inches
> for the reflector ( C-4 is on a side mount) to turn under the guy wire.
>
> I had my navsys engineer over here today (n4baa) and we determined that if we
> put a piece of I (eye) beam in the ground with 7 feet sticking up out of
> the ground and move the present guy back 4 feet (as far as I can go and still
> keep it on my property, with the guy attached at 7 feet the C4 will clear
> the guy wire by a couple of feet..
>
> I'm guessing I need a 10-12 foot section of eye beam with 4-5 feet buried in
> the ground to have 7 feet exposed. Is there a rule of thumb or does Anyone
> really know , how much do i have to put in the ground and do I need rebar in
> the hole and how much cement is required to make sure the I beam stays put??
> Tower is AB-105 Presently guyed at 40 and 70 feet, 2 el shorty XM 240
> mounted at 72 feet on a second sidemount.
>
> Thanks
>
> 73
>
> Chet N6ZO
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
>
> _______________________________________________
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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