Lots of great advice in this post, and also the one from N5WA. An
important shortcoming of the substituting carabiner for the pulley is
that as the trees sway in the wind, there will be much greater wear on
the support rope, and it will eventually break. FAR better to attach a
pulley to that rope using the method you describe. K2RD showed me that
trick soon after I moved here.
Another important point is that the rope for one end of a dipole must be
tied to a weight that can move up and down with tree sway. There's a lot
of tension on a dipole at 140 ft fed with RG11, so it takes a lot of
weight. I use a large water jug filled with dry sand (about 90#).
Lacking that moving weight, the antenna will end up on the ground sooner
rather than later. I learned that the hard way when I had an antenna
rigged between two pulleys but didn't yet have a weight ready to put on
it. Lots of wind a week or so later, and it was on the ground.
The quality of the pulley also matters. This is the one I use.
https://www.cmi-gear.com/collections/arborist/products/rp115?variant=633842217
Climbers love it because the sideplates rotate so you can lay the rope
into it rather than having to feed it through. Marine pulleys are also a
good choice.
73, Jim K9YC
On 6/17/2018 8:02 AM, Bob Shohet, KQ2M wrote:
When the carabiner is in the desired place in the tree, simply secure BOTH ends
of the carabiner and then pull up the other rope through the carabiner with the
antenna attached.
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