Hi.
A few weeks ago, I asked the question about how to handle a situation when
installing a guyed tower on an uneven terrain. In my particular
circumstances, I have one guy point that will be approximately 14' above the
tower base, one that is 3-4' below, and the third some 6' below tower base.
(I really don't have enough flat ground to get the guy points on the same
vertical plane, and in fact, one of them has to cross the house as it is!)
The advice given (and well received) was that I should adjust the distance
from tower base to guy points to ensure that all the angles were the same at
the tower. Well, this is proving much more difficult than I originally
thought. To illustrate the problem....
The configuration will be a 90' Rohn 45G (of which 40' is already up -
albeit unguyed at this time), and guy points:
[1] 14' above tower base. The closest I can get to the tower is 70',
because this is the one that crosses the roof of the house into
the front lawn (which slopes upwards quite steeply). This guy
point 'sees' a 76' tower.
[2] 6' below tower base. The furthest this can be away from tower
base is 82', due to the ground drops off VERY steeply into the
abyss, or canyon. This guy point 'sees' a 96' tower.
[3] 3' below tower base. No distance restrictions with this one.
This guy point 'sees' a 93' tower.
Unfortunately, with guy points [1] and [2], it is impossible to maintain a
constant guying ratio (and hence angles). However, after playing around with
an Excel spreadsheet, I was able to reduce the differences between all three
to a minimum. I get just under 5% difference at the lowest guy point on the
tower (35'); just under 10% at the middle guy point (60'), and under 15% at
the top guy point (90').
The question is: is there really a major problem here? [Please say "no", I
already have the base in and have sweated up the first 40' ;-)].
Thanks,
Darrell.
NR3Y/W6.
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