The Rohn SSV self-supporting tower series is a 400 foot tower that can be
custom designed to accommodate any load at any height (obviously a
reasonable load at less than 400 feet). Rohn will do (at least they use to
do) a quick design of what sections are needed for a specific load at a
specific height. For your 23 square feet of antenna, I suspect starting
with a 7N base section (20 feet per section thus 7N, 6N, 5N, 4N for 80 feet
or adding a 3N for 100 feet) would most likely do it. A number of
amateur's constrained to a self-supporting tower have utilized the SSV
series. The up side is that it is extremely low maintenance compared to a
guyed tower and the many issues associated with guy wires (like falling
over) are avoided. The down side is that you'll have to do some custom
engineering for the platforms but Paul K7PN of Custom Metalworks can easily
modify his 55G platforms to accommodate the appropriate SSV section. The
Rohn catalog gives you more than enough detail design data once the required
SSV sections are chosen for the height and load requirements. It isn't
cheap but the self-supporting tower cost really achieves a significant
cost/benefit ratio for long term use especially over guyed towers. Ken
K5RG
Message: 4
Date: Sat, 21 Mar 2015 02:16:31 +0000
From: Daniel Hileman <n9wx@hotmail.com>
To: TOWER TALK <towertalk@contesting.com>
Subject: [TowerTalk] Towers for large quads
Hi Everyone,
I am planning on putting up a Cubex Mantis II 4 ele on 20 through 10 and 2
elements on 40m. This is a large antenna...23 sq foot. I am planning on
putting it at about 100' on possibly Rohn 55G...My question is, does anyone
know of a free-standing tower that would hold that much square footage at
80- 100' other than maybe a super commercial grade tower? I dont figure
there is, and I figure rohn 55 Guyed should have no issues, but just asking
if anyone has experience with this. Anyone have this particular antenna? How
does it play? Looks like it should be a real great antenna...PS I already
know what a large under-taking this is, and all the potential pit-falls of
quads.
Thanks,
Dan N9WX
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