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Guying the HF9V Antenna
The HF9V is designed to survive winds of up to 80 mph 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.
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. The guy ropes should not
be tight. They should allow for some
movement of the antenna.
Synthetic Textile Industries Antenna Support Rope which is a premium double-braided
Dacron/Polyester rope has been used for guying vertical antennas. 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 degrees, 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 un-guyed 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.
