In this area a lot of 2-way commercial installations use a type of narrow
self-supporting tower. Typically they appear to be 80-100 feet tall, with a
base width of perhaps 2-4 feet. They are triangular, coming to a point at
the top. They generally hold only one antenna, a VHF ground plane.
I'm thinking such a tower might be worth considering for use as a 160 meter
vertical (perhaps with sloping wire reflectors), or as elements in a 2-el.
or 4-square array. Some top loading would be required, but could be done
with wires to minimize load on the tower. Of perhaps an aluminum mast could
be extended if the load specs would allow it.
Occasionally they become available used for the cost of removal.
Questions:
Who makes such a tower? Approximate cost?
Are they always steel or are some aluminum?
Are the sections welded together, or are they in sections so that erection
could be accomplished with a gin pole such as with Rohn 25 and 45?
Some appear to have a "tilt" base mount. Can they be "walked up" if aluminum
or using a temporary erection fixture and winch, or is a crane needed for
installation?
Once erected, can they be climbed? All the way to the top?
Has anyone successfully shunt-fed such a tower? Any problems with it being
tapered rather than straight tower?
Is there a base insulator made for such towers, or has anyone fabricated one?
Thanx any info. I'll summarize and send to the reflector if there's enough
interest.
73/Jon AA1K
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