>I am using LMR600UF; a bundle of 4 cables plus rotor running up
>my 72 foot US Towers crankup. I crank it up and down each time
>I operate (fancy neighbors). No problems, but I don't do it
>remotely, as I'm always afraid the motor will tear things up if
>the cable hangs up on something like the base of the tower. I
>also stay out there while the tower comes down to make sure every
>thing coils nicely.
I have the 72' base-rotated tubular version, which makes running the coax
even more complicated. I crank it remotely from 250' away, and when the
leaves are on the trees, I can't see it. After a near-disaster with the coax
hanging up on the motor housing (fortunately, the balun on the antenna
exploded, releasing the coax), I redesigned the system to avoid hangups:
1) Replaced stiff and non-slippery LMR400UF with RG/213 (more lossy).
2) Moved coax further around tower to be exactly opposite motor.
3) Added two coax standoffs on fixed section, one above motor and one below
(keeps coax from wandering around the base.)
4) Build cage out of hardware cloth around base of tower to keep coax from
snagging on rotor, base, bolts, etc. Works great.
5) Always raise and lower tower with coax arms facing same direction
(downhill, away from tower base, utility pedestal, etc.)
6) Shovel area around tower base every time it snows to keep coax from
getting stuck under crust.
So far, this has worked like a charm. Nothing is foolproof, but I checked
the coax dozens of times after making these changes and can't see how it
can get hung up. Now I'm pretty comfortable with raising and lowering sight
unseen. Lowering in the dark is safe, but if possible I try to raise it only
in the daytime, when I can just make out the elements through the trees as
they go up (in the winter I can see the whole tower.) I keep my hand on the
off switch just in case something doesn't look right. Also, I visit the
tower regularly just to make sure everything is OK. Believe it or not, I
seriously considered installing an infrared security camera so I could watch
the coax as the tower goes up. So far, I've managed to resist that
temptation.
Here's a good one: Bruce at U.S. Tower told me that some "old timers" put an
inverted galvanized washtub at the base of the tower under the coax. The
coax seems to naturally wind itself around the washtub. I haven't tried this
yet, and frankly I'm skeptical that it could possible work or wouldn't
encourage tangles and hangups (I can just see a loop of coax trying to carry
the washtub up the tower.) But one of these days I just might try it if I
can find one of those washtubs...
73, Dick, WC1M
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