John B. and I have been having a quick chat in regards
to the Decibel DB-224 antennas. John mentions something
interesting I thought would be worth posting back to
the group.
" we have found that to make these exposed element
antennas last more than a year or two around here, I
have taken to making "stiffeners" that I usually put
about half-way-up and half-way-down each of the loops
from the mast connection points."
Which is a great idea I never thought much about before
today. While we don't have the weather extremes in California
it would be nice to extend an antennas lifespan where possible.
A few years ago we had a large bird of prey fly into one
antenna and actually snap off a dipole element. We found the
bird and the element near the base of the tower. Not to mention
birds do land on the tower and antennas.
"I'll see if I can photo one, or do a really good sketch
of these thingies that others might find useful. (Last
year I replaced the 16/76 antenna atop Terry Peak -
see attached photo - as the wind had bent the bottom
mast section. Unfortunately the angle from which the
photo was taken doesn't really show how much the
bottom mast section - the reinforced part - was
bent. This same wind seems to cause the loops to
vibrate, and then breaks the Heli-arc'd joints. We
also use stainless steel screw-type hose clamps to
tie the harness to the mast for the same reason.
Ah,- life at 7,200 ft in the Black Hills!)
Great job, and thanks again!
73 de John WB6GHA"
You'd have to use a material with a low D-Factor, but a
hard type dipole reinforcement is a pretty good idea.
The Bluewave Company at the Las Vegas IWCE Convention
has extreme weather antennas on display. I really like
the rugged construction but the cost is at least double
the Decibel & Sinclair equivalent.
I'll keep the California earthquakes... you guys can keep
the snow and hurricanes.
Cheers,
skipp
www.radiowrench.com/sonic
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