John, This may be a bit simplistic but it may also resolve
your issues.
It has recently come to my attention that my local PUD while
removing power poles that have been trimmed by a fast moving
vehicle have needed a way to conveniently dispose of these
power poles that are now excess to their needs. Also, they
are no longer tall enough to match the other power poles.
The crews removing the poles have been known to leave them
on various neighbors property in a upright position suitable
for use as antenna. Did I mention that these dimensionally
challenged poles still range in length from 45 to 60 feet
long??, this is down from their original height of 90 feet
prior to ? vehicular pruning???
The acquisition cost for the neighbor was to have his power
bill up to date and a rack of beverage left on the bonnet of
the truck not to mention that they knew of his being a Ham
Operator.
While at my Rotary meeting as I sat next to the PUD
Operations Manager, I mentioned that I?d heard about an
antenna farm (2 former power poles) having been
accomplished during the late fall planting season. He smiled
and responded with the rather bland statement that ?they
had been assisting a Ham Operator with some of his frequency
issues?. He believed that they had, for the most part,
been ?able to resolve most of his issues?. ;o)
The most important caveat involved here is that they were
local to the recipient as versus being brought from the
south end of the county to the north end.
Good luck finagling yourself an antenna farm. Hope this
helps. Chris Veblen, kf7cob
> Hello jimlux, thank you for your response and suggestions.
> I will take all your points into consideration, and I can
> confirm that access to the site is clear, and any lifting
> problems can easily be resolved. Sincerely, John G3JVC.
>
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of
> jimlux Sent: 24 January 2010 18:21
> To: Tower and HF antenna construction topics.
> Subject: Re: [TowerTalk] "Roll your own" tower/mast.
>
> John E. Cleeve wrote:
> > Gentlemen,
> >
> > I would be grateful for constructive comment on the
> following problem. I am
> > in the market for a couple of 100ft towers or masts, the
> problem is that in
> > the UK there are very few manufacturers or suppliers,
> > and those that can supply new, usually import their
> wares from abroad. However, one quotation I
> > received from a UK manufacturer was for approximately
> > 12000 GBP per mast (guyed), at the factory gate,
> > carriage, guy anchorages and erection of the m
>
> $20K plus! clearly, you're paying a lot for the labor,
> since the metal cost is a tiny fraction of that.
>
> What you get with a conventional lattice type tower is a
> tradeoff of lower mass for more labor to build it. The
> lower mass buys you lower material cost (which is a tiny
> fraction of overall cost), but more importantly, the
> ability to erect a tall tower in pieces, by relatively
> few people.
>
> However, think differently..
> Are you mass constrained? Particularly for erection? Do
> you have room to assemble the entire mast on the ground
> before erection? Can you hire a 100 ft crane for, say,
> GBP1000 that can lift a few tons to 60 feet? (assuming a
> slightly above midpoint "pick").
>
>
>
> What about a suitable piece of iron/steel pipe (or, more
> properly, a series of pieces of pipe of decreasing
> diameter). Or stacked telephone poles?
>
>
> Yes, it's not what most hams use, because a 20 foot
> section of 6" diameter pipe weighs a LOT (about 600 lb)..
> you're hardly going to bring it home on the car top, or
> lift it up with a couple helpers and the "iwo jima"
> approach. However, particularly if you can find a surplus
> source for the pipe. Scrap steel, is, I think, around
> $0.25/lb these days, so a 20 foot length of 6" pipe with
> 1/2" wall is going to set you back around $150-200..
> Call it a couple thousand dollars for 100 ft worth, by the
> time you fabricate it.
>
> Actually, I'd be looking around for aluminum irrigation
> tubing in large diameters and use many tiers of guys.
> Around here, there's quite a bit of it available, but
> that's because there's significant agriculture (I live
> near the coastal plain in Southern California.. strawberry
> and sod capital of the world, I think). I don't know if
> temporary irrigation is something that is common in the
> UK (given that water falls from the sky directly upon the
> plain beneath, and doesn't need to be carried for
> hundreds of miles from the source)
>
> It's possible, although tricky, to erect something like
> this without a crane, but you're going to spend a lot of
> time and analysis figuring out how to lift it without it
> buckling, probably involving truss and cable stiffening.
> Think of sailboat (or sailing ship) masts.
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.730 / Virus Database: 271.1.1/2642 - Release
> Date: 01/24/10 07:33:00
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|