If the top loading wires have to slope down due to a lack of tall
supports, it makes sense to use as many wires as possible, so that
each one can be shorter (for the same resonant frequency) and thus
cancel a smaller portion of the current in the vertical
radiator. This assumes that the low support points remain at the
same distance from the vertical radiator and that the ends of the top
loading wires are supported by insulating extensions.
You can also create a spider-web by adding wires horizontally between
the ends and/or middles of the top loading wires. This increases the
capacitance and allows you to further reduce the extent of the
capacity hat and the resulting height of the sloping portion.
73, Terry N6RY
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