Double you two double cross states:
"Make sure you buy a continuous length, long enough to go up and
down your entire tower, plus 5-10% for working on the ground."
I STRONGLY [that's emphasis added] disagree..........
If you are using the rope for such activities as the tramming of yagi
antennas, the length must be long enough to go vertically up to the high
spot [top of tower mast] and must also be long enough to come down to the
ground AT AN ANGLE......and if you want to take the pull/down rope out away
from the tower through a pulley there is a horizontal length to add, too.
Geometry again, boys and girls...
So....if you have a 100 foot tall mast, and you are tramming from a point
which is significantly farther out than your guy points are to aid in
avoiding the dreaded top set (I say significantly because there is always a
"sag" in the tramming line's path) .....then lets say then for example that
you launch your yagi from 100 foot out, your rope needs to be:
on the angle: prox 141 ft [square root of two is abouts 1.414]
+ (100 ft vertical)
+ (horizontal pull rope - say 20 feet)
So, your rope should be at least 2.61 times the height of your tower!
Hence:
"Buy your main rope three times as long as your tallest tower's mast is
high and be comfortable with it"
(AKA OJ's Theorem)
[I like K5RC's garbage can idea for storing of rope.....hopefully my
neighbor will not get wise to my scheme to abscond with his "wheeled"
Rubbermaid product]
73,
Jim, K4OJ
Florida Contest Group - visit our website at:
http://www.4w.com/deemer/fcg.htm
The Florida Contest Group sponsors the Florida QSO Party, check out the FQP
website@:
http://home1.gte.net/wd4ahz/fcg/ssqp.htm
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