> I would tend to use stainless cable after seeing
> what happened to a 105 foot SkyNeedle in Florida 30 seconds after I
> descended from the platform (and the owner raised it to the top while I
> was climbing down)
The same thing happened to me a few short weeks ago. Performing
antenna replacement of some VHF/UHF sticks on a friend's 90 foot
US Tower. A buddy and I were up at the top of the mast (~18 ft over
the top of the tower) for about an hour. When we climbed down, the
owner started raising the tower and we were routing the new coax's
through the arms when the thing made a funny noise and then came
crashing down. It had been raised about 10-15 feet at the time.
The new antennas were toast, as was one of the large monobanders (a
telrex 6 el. 20).
Upon doing a post mortem (and changing my underwear :-) ) we found
that the cable snapped between the 3rd, 4th and 5th sections, causing
the top two sections to collapse into the 3rd. The bottom of the
3rd section is mangled from the impact as well. Luckily, the other
cables held, and the antennas didn't drive themselves through the roof
or ourselves! What a mess....
Of course, the broken cable was rusted clear through the inner strands
and had never been replaced (the tower was 10 years old).
I thought that stainless steel was not as strong for this application
as the galvanized type of cable. Although, if the cable doesn't rust,
this type of accident would not happen...yes, of course, if the
proper maintenance was done, it wouldn't happen either.
Personally, I'm glad my tower is guyed, not collapsing.
73, J.P. W2XX
--
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J.P. Kleinhaus, W2XX (fdba AA2DU)
E-mail: w2xx@cloud9.net
As we say in the software business: "You are hosed."
======================================================================
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