Evening/morning all,
My wife and I are celebrating tonight. We've just inked the contract to buy a
house in the Portland, OR area. Goodbye city life, back to God's country, and
adios to years of living under that dreaded term "covenants"! This will be my
first tower since 1978. And I was QRT from 1979 to about two years ago. Have
been existing with low power and a stealth vertical, camouflaged and butted up
against a big pine tree. Well, the new place sits on top of a ridge with a 360
view (except for some trees blocking Mt. Hood. And I'll be thankful for them
when it erupts. Much has obviously changed in 25 years, but I'm going back to
the basics of installing a tower.
Now. I have an idea. And please spare me the snide remarks. Besides, you'll
be much more tempted as you read on. In fact, as you read my idea, many old
Andy Griffith fans will be tempted to issue forth with Barney Fife's most
notable quote about Ernest T. Bass: "He's a nut!"
Because of health reasons, I cannot climb a large tower. Well, maybe I could,
but someone would have to lower me down. What I propose to do is install 120'
of Rohn 55G with four yagis. The tower will tilt over near ground level and be
raised with a roof-mounted electric winch. Now stop that! Hear me out first.
For purposes of explanation, say the house and roof ridge line runs east-west.
I do not have enough room on either side of the house to use the derrick/W3GM
method because the guy wires won't fit. The property is only (eat your hearts
out city dwellers) about 115' wide at the north end and slopes down hill to the
south, widening as it goes. Rohn specifies the guys to be 100' from the base.
And I follow the manufacturer's instructions. Right Uncle Steve? (And Rohn
doesn't say you can't torch a section in half and install hinge plates.) Trust
me, the guys won't fit in the side yards. On the south side of the house, the
distance from the tower base to the top
of the house ridge line is 25-30'. I have a total of 3 acres, but the
farther south I move the tower the lower it gets in relation to the crest of
the ridge. Now, 120' of 55G is about 1200#. Add to that a 95# yagi and a 55#
yagi, plus rotor and mast, at the top. Another 95# yagi will be at 90', and
another 55# yagi at 60'. Total dead weight will be approximately 1700#. Rohn
specifies 3 sets of guys, but I would install 4 at 30' 60' 90' and 120'. This
would help take the load of the lower yagis.
Now for the fun part, how to get this monstrosity up in the air. An electric
winch, designed for horizontal and vertical loads, would be installed near the
peak of the roof line, on the north side of the roof. I would heavily
reinforce the space between the two rafters where the winch would be mounted,
including steel plates on the roof and below the reinforcement, Using the bolt
pattern for the winch, long bolts would secure the winch through the top steel
plate/roof/reinforcements/and bottom steel plate. Would also install multiple
wood 2x8 bracing between multiple rafters and joists on either side of the
winch mount point. With guy wires running SE, SW and North, I would hook the
winch to the North running guy secured at the 90' point on the tower. Then
just pull that puppy up, attach all the other guys, release the guy used for
pulling the tower up from the winch and join an additional length so it could
be guyed to the north of the house with the other North running
guys. Simple.
Okay, now I'm ready. Lay it on me. And has anyone else been stupid enough to
try this?
73, Bob W7BJ/5 and about to be just old W7BJ (unless I get another call sign
to mask my identity)
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|