Get help from experienced individuals with known record of tower installation.
Realize that Rohn is lawyered up and that there is a lot of concrete in their
bases.
The base of a guyed tower is only there to resist downward compressive loads.
There is no overturning moment with a pin and not much in a bolted plate,
unless the guys are way loose.
If you have hard ground, you could pin a baseplate down with rebar, like my
club does every year at field day (only 30 ft, works fine).
Yes, you need temp guys, but you’ll need them anyway as you go up.
Four good guys and some beer can raise the first 30 ft in one piece, with a set
of wires already rigged.
Just tell the guys they can have the beer AFTER it’s up and they will make it
happen.
If you get a tilt base, you can easily raise the first 40 ft in one piece,
which we have done at field day for years. Read about falling derricks.
There are Youtube videos of 90 ft or so raising in one piece, but they are
scary.
Elevated guys are a great thing, to reduce the circle and to make the ground
under them usable/accessible. Think garden and mowing.
But they are a much harder design problem than the tower base, since the tall
guy anchor pole can exert a serious overturning load on the dirt.
If you are a good scrounger, some I beam or railroad iron sections can make
great posts. If you’re in the right area, especially oil country, you might
find pipe that will work.
There’s a lot of territory between irresponsibly stupid and the Rohn catalog
and I think there is a comfort zone somewhere in the middle.
Lastly, read the QST articles about beam performance vs elevation.
Sure, it’s macho to have a tall tower and height does get you some ranges, but
it also COSTS you gain at some.
So some thought about what you want the beam to do is in order and may save you
some installation effort.
Also think about the beam itself. Getting someone, even you, to do high
maintenance work is harder as the tower gets taller.
A simple, rugged beam that doesn’t need frequent work is worth giving up a dB
or two! You can always build a bigger amp!
Use good hardware and triple check everything.
You’d think that with all these opinions my tower would be up, but it isn’t,
HOHO! I’ve seen a lot of them though.
My dad’s radio club built two wooden lattice 70 footers in the 30s. When I was
a kid, early 50s, I was there to see them knocked down and replaced with steel
towers.
Keep us posted,
Wilson
W4BOH
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