Years ago Telerex made some side mount brackets/thrust bearings for
rotatable antennas mounted on poles. Quite generic, made from angle iron
and I assume, metal plate. The idea mentioned by Ed, below, using the Rohn
25 top seems a good one. Some years back I contacted McFarland-Cascade, to
compare pricing for a big pole vs Big tower, and was pleasantly surprised.
A Class A, 120 ft, pressure treated pole as I recall was about $7000
delivered to central California (with about half that being transportation
costs.) Weighed about 8K lbs. Probably another $1K to get it vertical
in a hole. And some more, (but reasonable) for installing pole steps. For
that you get a bullet proof, self supporting, climbable antenna support far
far stronger than steel towers, and it has a more acceptable eye impact
than lattice towers. The rule of thumb of the utility construction crews
around here is to bury it 10% of it's height, plus 2 ft. Assuming good
soil, the savings on non necessary concrete foundations would also be
substantial. One wooden pole manual I have seen rates some 60 ft wooden
poles as being able take a side lode at the top, of more than 1200 lbs....
I dont know the bottom line costs for a Steel Self supporter that is 120 ft,
but recon it is far more than an equivelant wooden pole....
Check McFarland Cascasde site: http://www.mcfarlandcascade.com/
73, de Pat AA6EG aa6eg@hotmail.com
>From: K4SB <k4sb@bellsouth.net>
>To: towertalk@contesting.com
>Subject: Re: [TowerTalk] Utility poles
>Date: Sat, 23 Apr 2005 14:20:54 +0000
>
>Barry Fox wrote:
> > Greetings to the list. Has anyone here used a standard wooden
> > telephone/utility pole to support an HF beam? I am thinking of having
>the local
> > utility install one at my QTH. The big problem I see is how to support
>a rotor. Does > anyone make a rotor and thrust bearing mount for such
>poles?
>
>Used to be pretty commonplace, but that was before the "big yagi" era.
>I've seen many which merely had a 2" pipe bolter to the top, with the
>rotor on the pipe, but don't think much of that idea.
>
>The one I remember which seemed to overcome the problem was a buddy in
>NC who "telescoped" a piece of Rohn 25 ( I think ) over the top of the
>pole so that about half was over the wood, and the rotor plate mounted
>just above the top of the pole. Seemed to work well.
>
>With the difficulty involved in climbing the thing, plus the other
>factors, I would think Rohn 25 would be a better and cheaper answer.
>
>73
>Ed
_______________________________________________
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
|