I have not seen any articles, soooo, last fall when I put up my 4el 40 I
invented my own methods... for better or worse, here is the readers digest
version...
I put a heavy eyebolt through the top of the mast, and also hung a pulley at
the same level... the top of the mast is 5' above the tower and the beam
clamps to the mast 1' above the the tower...I ran 3/16 EHS as a tram line,
from the front anchor point at ground level (a BIG tree in my case) 270'
from the base of the tower, up to the top of the mast, then through the
eyebolt and back down to the back anchor at ground level, 90' the opposite
side of the tower base... do not clamp the tram line to the eyebolt, allow it
to creep back and forth through the eye under load to minimize the side
forces applied to the mast... DO NOT use rope for the tram line, as it has
too much stretch, and the tensile load involved when the beam is at the mid
point is greater than you think ( assume that it is 10 times the weight )...
do not make the tram line too steep, the flatter the better... 1.5 times the
height of the tower is a minimum distance for the front anchor... the back
anchor can be closer... anchor points can be trees, ground augers, trailer
hitches on a car/truck, etc...
Then a pulley is installed to roll along the tram line, to act as the car,
and a pull rope is tied to the car and run to the top of the tower, through
the pulley hanging from the eyebolt, and back down to ground level to a
snatch point (about 60' from the tower base in my case) then through another
pulley at this snatch point so that you are pulling horizontally, when
raising the beam... do not tie the pull rope to the beam, you are pulling the
car, and the beam is a passenger only, and hangs straight down from the
car... I used my tractor to do the pulling... watch out for things getting
snagged so you don't snap the pull line or damage the tower... The pull rope
is braided dacron, not twisted nylon...
The beam is suspended from the car with a rope fall (block and tackle), and
is adjusted so that the beam is hanging down the same distance that the upper
pulley is above the tower... The rope fall travels with the beam and the end
of the rope fall has to be in reach of the tower crew when the beam is at the
top, so they can raise or lower the beam during the installation... (I am
raising beams too heavy to be grabbed by hand and muscled into position)...
You need 4 tag lines on the beam... one at each end of the boom to control
pitching and yawing motions, and one to each side of one (center) element,
about 4' out from the boom, to control rolling motion... run each of these
lines into the center of the boom to tie them off, so the tower crew can
untie and remove these lines after the beam is mounted... where the tag lines
bend/pass over the boom/element they are secured with a single wrap of black
tape, so the tape can be broken with a sharp tug, when removing the lines...
practice this with the beam at head height to get it perfect before the tower
crew has a problem at altitude...
Previsualize, previsualize, previsualize.... picture each step in your mind,
and try to figure out how it can go wrong and what you can do to prevent
that...
Have fun... mine went up smooth as glass in 30 knot winds... looked like a
747 lifting off..
Denny k8do@aol.com
>From jdcolson@aplcomm.jhuapl.edu (Jack D.Colson) Thu Jun 20 14:02:27 1996
From: jdcolson@aplcomm.jhuapl.edu (Jack D.Colson) (Jack D.Colson)
Subject: SS Reports - W4KFC?
Message-ID: <9606201302.AA17723@aplcomm.jhuapl.edu>
Jim - vic went to great lengths to have an unique sound to his signal! When
h finally purchased a Collons 32S-3(1?), I worked him on 40 CW and actually
came close to calling him a bootlegger! His signal was clean and didn't
sound at all like what it was supposed to! He spent some time adding parts
to the Collins to make it conform to his standard!
I did the somewhat the same in those days, my HV power supply had very little
filtering and very poor regulation which gave it an unusual characterstic.
73 - I have more memories but must go do some work!
Jack
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