Aloha,
Ok, have at last solved my collapsed/jammed MA-550
problem; have a new one now on order!!
However, I am thinking about ordering a "chrome-molly"
(if that is the correct term) mast to increase the full-up
height from about 55 feet, to more like 65 or 70 feet.
Assume a 20 foot long mast, with 5 or so feet down
inside the upper section of the MA-550?
I could not go to a different tower than what I already have
had for XYL reasons! Also, already have an oversize
block of concrete in the ground holding up the present
MARB rotating fixture for the MA-550. Block is 2+
tons; 3x3x6+ ft deep.
So, my beam is "only" a C4. Any ventures as to the size
of mast, if it is a reasonable idea, to put atop the MA-550
to lift the 39 lb., 6.4 Sq. Ft wind load, and 18 foot boom C-4?
Longest element is the 40 meter EF-140S riding on the
boom just ahead of the pair of 20 and 15 meter reflectors.
Now, all this assumes it is possible to "push up" the
antenna on the mast, then lock in place from a ladder
strapped to the lowered MA-550; do not know the
weight of such masts, but that plus the 39 lb.
antenna would be the push-up load.
As I already have the motor to raise and lower the MA, I
will drop it all down when the trades go above 30 mph.
Maybe this isn't a good idea.
Thanks in advance for any comments, suggestions.
Mahalo and 73, Jim, KH7M
On the Garden Island of Kauai
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