Rule 1: do what the manufacturer says.
Rule 2: if rule 1 doesn't work hire a real engineer.
Rule 3: if you don't follow rules 1 or 2 buy lots more insurance.
The forces on elevated guy points are MUCH different than straight in
anchors. Not only aren't they pulling against the soil the way a normal
anchor is but they have to deal with overturning and uplift forces that can
be very large.
Some other ideas:
First, why not move the c4 down to 40' just above the lower guy, that should
give you the most turning room with the present guy system.
Second, move the 40' guys down lower on the tower to the 35' level to get
even more room, no extra wire or hardware needed.
Third, move the 70' guys up on the tower. You say the top antenna is at 90'
and the top guys are now at 70' so there must be some room to move them up
higher which would give you even more room and not require changing anchors,
it would require longer guy wires though.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of ChetMoore
> Sent: Wednesday, October 19, 2005 23:50
> To: 'TowerTalk'; pvrc@mailman.qth.net
> Cc: Marion Wise; James Lehnerd; VERB@VISI.NET; Dallas Carter; Jose
> Castillo; John Crovelli
> Subject: [TowerTalk] ELEVATED GUY
>
>
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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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