FWIW: I have a UST 55' crank up, tilt over with a 3 element SteppIR on
it. I only crank it down for maintenance, so your situation may be
different.
My standoff arms are in alignment; coax is not attached to the arms
(except the top arm, where I have some home-made strain relief to prevent
tight bends to the cables). I simply let the coax fall on the ground (with
a little manual dressing to prevent tangles) when cranking down. There are
3 coaxes, the rotor cable, and the SteppIR cable. (There is a terminated
dipole hanging about 4' from the top, and a half-sloper attached to the
top of the second tower section.)
I built a sawhorse affair (2x4s, extra bracing) that is about 4' high. I
place this under the tower when tilting it over, such that the tower rests
on the sawhorse just as the beam boom touches the ground. I can then work
on the beam using a small step ladder. I keep just a little tension on the
tilt-over cable in case the sawhorse has a problem, but I have no sense
that it is overloaded.
I wondered about grounding/contact between the tower sections. It is
probably unnecessary, but I attached a #10 copper wire to the top
stand-off and let it run down with the cables; it is then connected to the
main bolts (between stainless steel washers) at the bottom of the tower.
Between the tower itself, the coax shields, and (maybe) the extra copper
wire, I seem to have a "wide" tower that loads fairly well over most of
the 80m band (using a half sloper). Half slopers have a mixed reputation,
but I finished my 80m DXCC with it in about a year (and I am not all that
active on the air).
The tower is in a substantial concrete base, with an average amount of
rebar. I also have three ground rods with clamps that I try to check
several times each year. (One of these days I want to experiment with
Cadweld.) I am not in a lightning-prone area and there are lots of trees
around that are as high or higher than the beam. I have about 30 radials
attached to the ground rods.
The two winches that came with the tower (about 8 years ago) are OK. I am
not quite as young as I was a few years ago, and cranking the tower up or
down is a job that I usually do in several steps. If I cranked it down/up
more often I might consider different winches. The motorized drives are
very expensive for something that I might use once or twice each year.
I have a 10' (?? cannot remember for certain) chromealloy (??? again I
cannot remember for certain) 2" mast that I purchased with the tower..
Very heavy steel, whatever it is. I have the beam about 3' above the top
of the tower, and about 3' of the mast extending above the beam. I
extended this another 3' with a PVC pipe and have dacron ropes going from
the top to the ends of the driven SteppIR element (which is the 40m-6m
"trombone"). This pretty much removes the sag from the element. The sag
probably does not hurt anything but it does not look good.
This is just my experience with a UST crankup and it might or might not
apply to your situation.
Bill
W2WO
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