In order of preference:
1. Hire KC1XX
2. Hire a crane
3. Disconnect guy wires and lay the tower over in the next windstorm
4. Follow my procedure below
I'm a little guy (160 pounds) and not particularly muscular. Despite that, I
owned a KLM 4-element 40 for a while, and I'd have to say the only way I could
imagine replacing the reflector without a tilt boom/mast bracket such as the
PVRC mount is to use a rope sling from a pulley or gin pole higher up the mast,
as suggested by others on here, to support the boom while you slide the boom
horizontally enough in each direction to temporarily remove the inner two
elements one at a time. (With my size, I'm always in favor of getting as much
weight and as much torque off the antenna as soon as possible.)
Then, with two of the three elements gone, I'd try to continue the rope sling
process until I had the remaining element in reach or at least until I had the
center of gravity of the boom/element assembly right at the mast. I'd follow
K1TTT's suggestion to have a tag line to ground (or a lower person on the
tower) from the end of the boom with no element on it. At this stage, I'd also
rotate the boom in the bracket until the element is vertically polarized.
Re-tighten the boom-to-bracket bolts, re-position the rope sling (or use a
second one), and make a failsafe knot around the boom between the tower and the
element. (Use muffler clamps or other U-bolts to stop the rope from sliding
unexpectedly on the boom.) Then completely disconnect the boom from the
bracket and while supporting the boom/element monstrosity with the rope from
the pulley above, roughhouse maneuver the whole mess until the boom is
vertical, hanging alongside the tower, and the director is horizontal, wi
th its boom/element bracket laying against the tower some number of feet below
the top. (The reason you go vertical polarization before this process is so
the director will clear the upper guy wires and so someone a little lower on
the tower can catch the end of the director as you're performing this little
windmill stunt, after which they can then gently guide the rotation of the
element tip past the tower the rest of the way.)
At this point, the whole assembly can be slowly slid down the tower a few feet
until you can conveniently reach and work on the end of the boom that's missing
a reflector. Tie the boom off in a few places to the tower, haul the reflector
up and reinstall it, add a heavy-duty tilt bracket to your mast, do the
windmill in reverse direction, put your two driven elements back on with the
aid of the tilt-bracket, and you're in business.
See how simple that is?
Or, you can follow an alternate conclusion, as has been suggested by Steve, and
do as I did, too -- sell the beam....
HTH.
Bud, W2RU
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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