In a message dated 96-09-16 00:28:24 EDT, you write:
>I may be getting confused, but if this was the 20M yagi on 48' boom, I
>think that's more than an "average antenna," and I'm personally not
>surprised that one person (unless you're 200 pounds plus) might not be
>able to move it.
Hi, Rich --
In my book, a 48' boom 20M antenna is not an average antenna. Might be
standard for a medium to big gun but bigger than normal. And the 20M Telrex
you mentioned is even BIGGER.
>I have done a lot of single handed work here with the Telrex 6-el 20 (46'
>boom, 175-200 pounds I guess), 8-el 15 (similar size and weight) and
>homebrew 3-el 40, which I put up single handed but first the boom then
>each element by itself. I find the maximum pull on a rope is like
>ringing a church bell, pulling straight down on the rope, using all your
>body weight to pull down. It's just possible to raise an antenna of this
>class this way with one person. The hardest part is when you have to
>hold its weight with just one hand while you use the other hand to tie
>off the rope. I don't recommend it; it's at the limits of one person's
>capabilities (or beyond).
A device that will enable you to do this is used in mountain climbing
circles and is called an ascender. It's used for ascending a fixed rope. It
clamps on a rope, slides in one direction and locks in the other. In an
antenna rigging situation, you install it upsidedown so that you can pull the
rope down but it locks as soon as you let go of it. There are several
manufacturers including Gibbs (I use this one), Jumar, etc. Check with REI,
Northface, etc. for what they carry. Figure $30-50 for one.
>
73, Steve K7LXC
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