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Message: 1
Date: Mon, 8 May 2006 10:05:25 -0700 (PDT)
From: Dave Tipton <dave@lodave.org>
Subject: [TowerTalk] Rohn 50 Foot Push Up Mast
To: towertalk@contesting.com
Message-ID: <20060508170525.97653.qmail@web502.biz.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Ok, so I have a 50 foot mast pushed up to about 35 feet and guyed near the
top.
I'm thinking about adding a second set of guys (And replacing the other
set) with some small phillystran to set up as a second "High" point in the
yard.
My question is this... What is the actual wind load rating that this mast
can handle in that configuration?
I'm planning to add a couple small antennas to it...
1. Center support for a rather cumbersome folded dipole.
2. 6M Ho Loop
3. 2M Ho Loop
4. 8Foot 2M/70cm Vertical
5. If it can handle it, a 3 Element Vertical 2M and a 5 Element vertical
70cm antenna with a TV Rotor and a 4 foot mast.
The Ho Loops will be mounted, just below the top guy points.
I also have the option, in this case, of guying at 20, 30, 40 and 50 Feet,
but would like to keep it to 2 sets of guys, and 3 absolute max.
So far, at 35 feet, it's withstood an 80MPH wind with one set of guys.
Ok gang... Talk to me.
OK - This will be heresy, but.......
I have 3 40' PU masts - keep planning on putting up a 40' Rohn tower I have
in storage but never seem to get around to it.
The first is supporting a CushCraft MA5B mini beam with a TV rotor. Been up
there going on 3 years without bringing it down or it coming down on its own
- one of those, "If it ain't broke, don't fix it" things, I guess. It is
setting about 2' in a PVC pipe cemented about 3' in the ground) and is
supported with four sets of Dacron rope guys and it looks like - you know!
The second one supports a 12/ 17M rotary dipole with TV rotor, and a small
2M GP vertical. It's supported at the roof peak and has two additional sets
of rope guys. Been up there (and down and up) for a little over two years.
It also supports one end of a 30M dipole and is a center support for a
double G5RV.
The third is again in a PVC pipe cemented in the ground and it supports a
30M 5 element sloper array, plus one end of another 30M dipole. It has 3
sets of rope guys plus the top semi-supported by the sloper elements.
Many a sleepless stormy night I have sat staring out the window and watching
them dance around illuminated by lightning - kind of like a boat bobbing on
a rough sea. They have survived many summer T-storms and high winds, and
winter ice storms, and don't seem to sway much, but there isn't much up
there to catch air.
I don't recommend this as standard fare for anyone but it does show that
they can be reasonably resilient. Maybe this is the year I will get that
tower up and then the mini-beam and dipole will go on that - then maybe the
masts will get relegated to something more appropriate - who knows!
Anyway - good luck!
John K0JJH
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