Towertalkians who are leery of putting beam antennas on tilted horizontal
crankups may be interested in how I installed the Steppir Monstr on my LM470
motorized crankup. I say I installed but actually my older eyes mostly watched
while three helpful hams did most of the work.
One of the helpful hams was a retired civil engineer and he thought of using
the tilt raising fixture to tilt the tower, with one end of the fully
assembled Monstr attached, up until it would be at the proper angle for
extending the tower through the booms U bolts on the boom-to-mast fixture. The
other end of the boom was mounted on a four wheel nursery type cart so that the
boom end would not scrape on the ground as the antenna assembly was dragged up
and toward the tower.
In order to lift the antenna high enough at its pulling up end so that the
u-bolts in the center of the boom would be lined up correctly for the mast to
go through them, the tower was initially extended ~10 feet. When the tower was
at its correct tilt for the mast to go through the u-bolts, the boom end was
taken off the wagon and firmly anchored to the ground. A wire rope that had
previously been attached to the top of the outer-nonmovable section of tower
was brought away from the tower about 80' and firmly anchored taught to hold
the tower in place. (We used my Kabota 4-wheel drive tractor for the anchor)
As a safety precaution an 8' pole (6" diam) was placed to hold the tower --just
in case).
The wire rope that had been pulling the tower up was detached, the tower
retracted and tilted back down until the mast was in line with the mast-to-boom
u-bolts. The tower was then easily extended through the u-bolts. During these
operations a ham was at each end of the lowest element holding on to a rope
that was slung over the element in order to be able to steady the antenna
assembly. Just a little jiggling enabled the mast to wiggle through the
u-bolts.
A ham them climbed a ladder to tighten the u-bolts. Note that the Monstr was
installed at only about a foot above the tower so that the ladder was not all
that long. All of the wiring had already been connected and tested.
THERE WERE NO "SCARY MOMENTS"
k7puc
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