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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