Towertalk
[Top] [All Lists]

Re: [TowerTalk] fiberglass masts

To: <atrampler@att.net>, <towertalk@contesting.com>
Subject: Re: [TowerTalk] fiberglass masts
From: BRENT BAUM <brentbaum5323@msn.com>
Date: Thu, 11 Dec 2008 10:48:20 -0700
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
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@att.net> To: towertalk@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@att.net> 
_______________________________________________> > > > 
_______________________________________________> 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

<Prev in Thread] Current Thread [Next in Thread>