I've used these Rohn push-up mast extensively for the past seven years for
Field Day, temporary antenna supports, and have two in a fairly permanent
use now. I have one lashed to a tree at two points as it rises through a
Black Olive tree and rises about 12' above it. It anchors one end of my 80M
dipole. I have the two bottom sections of another bolted together with only
two feet of the 2d part extended that supports a Cushcraft A4S beam. The
entire mast assembly is anchored to the wall of my elevator housing on the
fourth floor of my house. I fabricated two standoff brackets with thrust
bearings at the 2' and 8' points and anchored them to the elevator housing
wall. The T2X turns the mast from the bottom. I've had this up for 4 years
and through two hurricanes without a problem. (I do take down the yagis
when the hurricanes are threatening,
For Field Day, I used one guyed at four points to support an A4S tribander
but did not use the top section since it was too flimsy to even think about
using it to hold the tribander. This whole setup was too scary to repeat,
not to mention the effort necessary to erect it by mounting the yagi and
pushing up the whole thing while standing on a ladder as helpers anchored
the Dacron guys. I switched to an Alumna freestanding tower for subsequent
years. We did continue to use two of these to support a delta loop that
sloped down to a 20' push up flagpole, and one more to support the center
of an inverted Vee.
They are good for temporary supports, and even for a more permanent support
provided they are securely guyed or attached. I do recommend you drill the
sections and install two SS through bolts at each section joint. I would
never trust those SS push pin thingy's that come them.
They have weathered remarkably well here in an ocean front environment.
Jon Hamlet, W4ZW
Casey Key Island, Florida
"A little piece of paradise in the Gulf of Mexico"
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