Well, I finally put the motor on my LM-470D today and cranked it up for the
first time. This was not a new tower, but one that I purchased several years
ago and very gradually worked to get up and ready. Today was the big day when
I was going to finally see it in all of it's glory and splendor. We put the
motor on, plugged it in and started cranking it up! It went up as good as
most crank ups and better than many I've seen. A few groans and creaks, a
minor lurch or two, but steadily upward, looking good and even. I was
cautiously standing next to the tower, operating the motor control switch.
The thought had occurred to me that the cable COULD break, but I really
didn't think it would. It is 3/16 19strand cable and I figured it would be
okay. I got it to where I thought it was all the way up, as it began to load
the motor. I stopped. I walked around the yard, looking up to the 70+ feet
that my antennas would soon be at. Straight, not leaning, the overlaps looked
good. Okay, time to bring it down and block it so we could put the steps on
the mast and hang the 80m inverted vee. My friend started to see if it had
any more "up" left in it, moved the switch to the "up" position, the tower
began to go up a bit more, then stopped. He let go of the switch at exactly
the same time that there was a metallic "ping" and the whole thing just went
zipping back down, nesting itself. I yelled and he scrambled away as it
began. I saw the whole thing. Nothing flew off, no parts laying around,
thankfully no expensive aluminum on it!!! It nested in probably 2 or 3
seconds. It bent or broke all of the braces that hold the shivs for the
cables, blew off the stops, and bent and mangled the tops of at least 2 of
the sections. The 25' mast was jammed down into the tower another 6 to 8
feet, with the T2X coming to rest on the pull-down cable spring, punching a
hole in the bottom of the rotator. What a mess of cable and rotator control
cable. What a very bad 2 - 3 seconds. As a good friend of mine says - "three
dits, four dits, two dits, dah, radio! radio! rah! rah! rah!"
There is a lesson here - re-cable your used towers! Invest the time and
money. It is a small price compared to the total loss (practically) of an
expensive crank up. It may be repairable, but only by someone willing to put
in MANY MANY hours and having excellent welding skills. I don't have those,
so if anybody wants this tower, make me an offer.
73,
Mike K7NT (ex AA7NX)
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