[Towertalk] UV in So. Cal. - was "Coastal Corrosion"
Larry McDavid
lmcdavid@lmceng.com
Tue, 03 Sep 2002 21:58:19 -0700
> If the West Nile virus lands in Los Angeles, it will have to be carried by
> something other than mosquitos, since we don't have any... -WB2WIK/6
Let me add the following observations:
The Texas coast is rampant with both bugs and antenna-eating salt spray
corrosion. When I grew up there, Galveston had a fleet of Jeeps with
powerful DDT sprayers trying to control the mosquitos; nothing
controlled the corrosion. Today, you can't spray DDT and you still can't
control corrosion there.
I think I saw a mosquito once in Los Angeles. Must have come in on an
airplane. In Texas, they may eat antennas, too.
Here, I have a thirty-year old Tristao tower. It is hot-dipped
galvanized and has not one spot of rust anywhere on it. But, I've
replaced a lot of hardware and wire rope in routine maintenance. Yes,
earthquakes do shake it some; they shake me some, too. Especially when
they are centered only five miles away. But, it probably beats worrying
about hurricanes for an anguish-filled week; these also wreak havoc on
antennas. But, not in Los Angeles.
Lightning storm is an oxymoron in Los Angeles, unless you own a mountain
top repeater. I've never had lightning at my QTH; this shows how
effective my porcupine static dissipater is....
Monel is a trade name for a class of nickel/copper alloys, typically 66%
nickel, 30% copper, 1% iron (!), and a bit of manganese. It forms a
natural, attractive patina and has outstanding resistance to salt water.
It is absolutely better than the 300 series stainless steels in salt
spray. Alas, it is expensive and not found at your local Home Depot.
I've never seen a Monel antenna but if I lived on a salty beach I'd look
for one.
UV from the sun affects antenna parts. It affects parts of me, too. I
wear wide-brim hats and still require maintenance. So do my antennas.
Lastly, most everything corrodes; it is only a question of rate. If you
put up an antenna and forget about it, expect surprises. Routine,
periodic maintenance should be a routine, periodic part of your life.
Even in Los Angeles. Don't forget that things come loose, too!
--
Best wishes,
Larry McDavid W6FUB
Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland)