>Good advice but I have two recommendations:
>
>1. Crank tower down BEFORE a storm approaches, if you happen to lose
> ac power how are you going to get the tower down?
>
>2. I have seen an accident using a remote control unit and not actually
> observing the tower coming down. I got rid of the remote control I
> had and stand right at the tower ready to stop it if trouble happens.
On #1 - Good point! I do lower the tower whenever a storm is forecast. The
anemometer is there to catch freak distrubances missed by the weather
forecasters. They might say max winds will be 15 MPH one day, then we get a
series of 30+ MPH gusts. Rare, but it has happened. Just this past week they
predicted 40+ MPH one day and it never got over 20 MPH. The next day they
said 5-15 MPH and it hit 30 MPH. The second the alarm went off (at 25 MPH),
the tower went down from 50 feet to fully nested at 22 feet. Monitoring
weather forecasts is the primary defense, but I recommend an anemometer as a
backstop for when NOAA gets it wrong.
One #2: Well, my tower is 250+ feet away down a steep hill. Half the year,
when the leaves are down, I can see the tower going up and down from my
shack window (assuming it's not dark.) The other half I can't see it until
it gets to about 60 feet. I have to carry a step ladder down there to get to
the switch (then climb back up the hill with the ladder.) Yeah, I could make
a mod and relocate the switch into a utility box next to the tower. But, to
tell you the truth, I'd just as soon not be standing near the tower when it
goes up and down. If a cable snaps there won't be any warning and one could
easily get bonked by flying debris. I have a lot of respect for this
tower -- so I like to keep away from it while it's operating.
But your point is well taken: I had a near-terrible accident shortly after
putting the tower up -- the coax snagged on one of the support struts for
the relay box. Luckily, the snag happened just before the tower reached full
extension. I could actually see the tower above the trees at the time. There
was a moment of violent buckling of the tower, during which I was thoroughly
confused about what was going on. Thankfully, the SO-234 pulled clear out of
the BN-86 balun, causing the balun box to explode and the coax to pull free.
The balun and coax were both destroyed. Fortunately, the cables were OK and
didn't get damaged or stretched.
This accident was caused by 1)placing the standoffs too close to the motor,
2) using stiff coax (LMR400UF), and 3) lack of a fifth and sixth standoff to
prevent the cable from snaking around the tower. I corrected the problem by
1) moving the standoffs opposite the motor, 2) switching to RG/213, 3)
adding two more standoffs above and below the motor, 4) building a cage out
of hardware cloth to deflect the coax from getting into mischief anywhere
around the base of the tower. It cost me about $150 to recover from the
accident and install the fixes -- cheap compared to what it almost cost me!
I also religiously follow a policy of rotating the tower to a specific
position when raising and lowering: the standoffs face away from the base
vertical member and the coax is positioned to "fall" down the hill away from
the tower. I have watched that thing go up and down many dozens of times
over the past year and am convinced that there is no way the coax can get
fouled now (knock on wood...). However, I do have to keep the area around
the tower shoveled clear of snow, otherwise the coax might get trapped under
a layer of ice (it coils up on the ground -- loops are not feasible with the
tubular tower, especially it you want to raise and lower it unattended.) I
still visit the tower a lot to inspect the coax status, but it's just not
feasible to stand next to it every time I need to raise or lower it. So far,
so good.
73, Dick, WC1M
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