[TowerTalk] fiberglass masts

[BRENT BAUM]

Just remember that the masts these guys are selling aren't antenna masts - they're the supports for camoflage netting and once they get past about 16 feet they get rather bendy, like the tree they're designed to simulate. Military antenna masts are tubular aluminum and guyed about every 12 feet (3 sections) up to about 36 feet maximum. The last 2 sections of such a pole are usually "dielectric" sections, i.e. fiberglass, to prevent interaction with various ground plane or yagi type antennas in a vertical orientation. 36 feet was about the maximum we could put up due to weight, leverage, flexibility, and stealth factors overcoming even the most skilled antenna erection crew working from the ground.
 
You may have some success bundling the poles as you suggest, with plenty of guying.
 
Just my 2 cents, I spent 21 years in the Marines as a communications electronics officer putting up and taking down lots of antenna poles and camo net.
 
73, K7MEI, Brent> From: atrampler at att.net> To: towertalk at contesting.com> Date: Thu, 11 Dec 2008 10:08:14 -0600> Subject: [TowerTalk] fiberglass masts> > This is an antenna support question...so hopefully it is close enough to a tower to allow a little discussion!> > I have been thinking about constructing an antenna support of military surplus 48" fiberglass masts. I would like to get up close to 70', though, both for an inverted vee and to run a wire vertical up it.> > Here is what I am considering: using 3 of the masts, joined with U-bolts around (or inside?) of 6" or 8" diameter PVC pipe, sliced into 3" or 4" pieces. I would rather use u-bolts than drill/bolt through so as not to weaken the fiberglass, and also to make keeping things even a bit easier.> > I would guy this at two, or if necessary three levels with dacron rope.> > So am I crazy? Or is there a real structural advantage to this over a single, guyed mast such as the one sold by MFJ? > > For the vertical, I am playing with the design for the relay-switched dipole that was in QST a few months ago, using ladder line. With such a design I could put relays for each band (two each on 40 and 80/75) for full coverage with very little, or without compromise. Perhaps I could later add base-loading for 160, or a combination of top loading/capacity hat switched in/out and something at the base. The fiberglass would lend itself to this, and to supporting an inverted vee.> > Feedback is appreciate, and since this isn't a true tower (of steel or aluminum), please feel free to contact me directly.> > Art, KØRO> atrampler at att.net> _______________________________________________> > > > _______________________________________________> TowerTalk mailing list> TowerTalk at contesting.com> http://lists.contesting.com/mailman/listinfo/towertalk