To the OP: unless you have installed, been part of an installation, or have at
least witnessed an installation of an antenna, asking "how to install...." is
like asking how to do an engine rebuild or doing brain surgery over the
phone. If you've at least seen it done, one can appreciate what it would take
to raise an antenna through, above, or around guy wires. One has to be able
to visualize in three dimensions how the antenna will have to be turned,
lifted, or manipulated to go from the ground to the mast on top of the tower.
Sorry to be blunt.
That being said, 4 of us raised my F12 240N to the top of my 90 foot tower with
a capstan winch. One guy was on the tower. One guy was running the winch, and
two of us were on tag lines. We basically pulled the elements out from the
tower as the antenna was being raised. Once we got the elements over the top
guy, we were able to let the antenna 'move' to the tower, and it went straight
up from there.
The way we installed my two C31XRs was to use a tram. But not the typical
tram. I don't have much room in the backyard, and the open area is not 'in the
middle between two guy anchors.' There is also a tree immediately adjacent to
the backyard open area. What we did was run the tram line over the house to a
tree. I attached the end as high as I could go (about 25 feet). The other
end of the rope went to a pulley on the tower about 10 feet above the ring
(where the antenna was going to go). The rope then came down the tower, then
to another pulley and went horizontal. At a tree (in line with the horizontal
rope), we then used 3 come-alongs. They were extended (so 30 feet). A second
rope went to a second pulley a few feet below the first pulley. Another pulley
was 'attached' to the tram line (so it rode the tram line), and the rope
brought down so it attached to the antenna. The second rope then came down
the tower and was wrapped around the capstan winch.
First thing we did was to pull on the tram rope to take up as much slack as
possible. Then a loop in the rope to attach to the come-along.
Tension the come-alongs (which 'raises' the tram line), as the tram rope is
tensioned (ie: raised), the antenna is also raised. As the antenna gets higher
and clears the guy wires, then start pulling the antenna toward the tower. The
tram rope will sag, so you have to keep tension in it (hence the 3
come-alongs).
As the antenna gets close to the tower, one can even let off tension in the
tramp rope and the antenna will "move" down to where you want it.
In the case of the OP, if you have several feet of tower above the top guy, you
can just do the same thing as above. When the antenna gets to the tower, tie
it off, and re-rig so there is a pulley at the top of the mast (you will need
at least 4 feet). Attach the rope to the antenna, and raise it straight up..
Tom, N2SR
From: "john@kk9a.com" <john@kk9a.com>
To: towertalk@contesting.com
Sent: Thursday, June 16, 2016 1:02 PM
Subject: Re: [TowerTalk] Raising a TH-11 DX antenna
I rarely use tram lines, I find it much easier plus its a quicker set up
to pull it straight up. Like Gerald said a tag line can help guide it
around obstacles. I use two tag lines on each side of the boom and so I
can steer the beam and also pull one side down when mounting if not
perfectly balanced. While I am not recommending this since every tower is
different, I have temporary removed a guy that was in the way of the
install. A TH-11 is not a large antenna however having multiple elements
so close to the center can make this a little tricky.
John KK9A
To: w8qwdave@casair.net, towertalk@contesting.com
Subject: Re: [TowerTalk] Raising a TH-11 DX antenna
From: TexasRF--- via TowerTalk <towertalk@contesting.com>
Reply-to: TexasRF@aol.com
Date: Thu, 16 Jun 2016 11:20:34 -0400
Dave, you have to have competent ground help to do all of the weight
lifting. With upwards of a hundred pounds of weight the man on the tower can
only help.
Unless you have obstructions near the tower you should be able to mount a
pulley up on the mast to use in lifting the antenna. The higher, the better.
As the antenna reaches the top, the tower man can manipulate the elements
around the guy wires, one at a time while the ground help slowly raises the
antenna. The elevated pulley is key in allowing the antenna to be moved
around to clear the guy system. An additional rope (tag line) is helpful to
allow the ground help to pull the antenna away from the tower as needed.
The tram system works well but for antennas the size of a TH11 you can
install the antenna in less time than rigging the tram setup.
These are my opinions; as in every task, there are multiple methods that
will work.
73,
Gerald K5GW
In a message dated 6/16/2016 9:52:17 A.M. Central Daylight Time,
w8qwdave@casair.net writes:
I have one of these beast that I have resurrected and am ready to put on
top of a 70' Rohn 45 tower. The tower is properly guyed and
steady as a rock. My question though is how to get the antenna from the
ground to the top of the tower.
At Dayton this past spring I bought the ARRL's book on towers and antennas
and have been reading about "tramming" the antenna to the
top and then placing it accordingly. That seems attractive but this is a
very heavy antenna and my concern is the strength of the
mast to hold the rope tight while the antenna is making its way to the top.
My understanding is that in the "tramming" method the antenna is carried
to the top by a sling (more or less)and then put in place
once it reaches the top.
The other method involves sliding the antenna up two ropes spaced apart at
the bottom of the tower, beyond the guys wires. This
sounds good but there are phasing tubes on the underside of the TH_11 that
could be (most likely would be) damaged in this method.
I've thought abut paying a guy to bring in his crane (lots of height and
lifting capacity), but that's another cost that I'd like to
avoid if at all possible.
So, I'm open to suggestion and the wisdom of the group's experience.
Thanks in advance.
Dave, W8QW
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