Butternut HF9V, Инструкция по эксплуатации

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GUYING
The HF9V is designed to survive winds of up to 80 mph (129 kph) without guying
in the absence of ice loading or heavy precipitation, but over a period of time it is
to be expected that frequent or even constant flexing or vibration will reduce the
chances for survival in winds that would not damage a newly installed antenna.
Therefore in areas of frequent or heavy winds a set of short non-conductive guys
should be used to reduce the stresses that wind loading will impart to the lower
sections of the antenna. In this connection, it should be noted that light nylon
twine is totally unsuitable as guying material because it has too much stretch per
unit length, although the heavier sizes of nylon rope (or even sash cord) may be
suitable if used in short runs. Polyethylene rope may be used, but because some
grades tend to deteriorate fairly rapidly, periodic inspection should be made. A
single set of guys placed just above the 30 meter circuit will contribute greatly to
the stability and the longevity of the antenna, provided that the guys retain a slight
amount of slack and do not come off at too steep an angle. At Angles of less than
45
/
the guys begin to exert a downward compressive force on the structure that
can be more of a threat to survival than lateral wind loading on an unguyed
structure. Under no circumstances should guys be placed higher than one-third of
the way up the antenna. The upper two-thirds of the HF9V has little more than its
own weight to support, so these sections may be allowed to bend with the wind
with no serious risk of damage. It is the lower third of the antenna that must
support both the weight of the upper sections and the wind loading on them and
are thus more likely to receive damage in severe winds.