Practical_Antenna_Handbook_0071639586

C h a p t e r 2 8 : S u p p o r t s f o r W i r e s a n d V e r t i c a l s 651
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Figure 28.22 4 × 4 antenna support.
Even if ground-Âmounted, full-Âlength l/4 verticals (35 ft, more or less) for 40 m require
guying unless they are made of extremely strong, self-Âsupporting members. A
full-Âsize 40-Âm vertical is akin to a very tall flagpole and requires similar construction
unless it is guyed at one or two levels. Even with guying once it is fully vertical, the
tubing must be strong enough to not bend or crease while being pulled or pushed up
from horizontal to vertical. The problem is even more severe for l/4 80-Âm ground-Â
mounted verticals. Irrigation pipe, either butt-Âjoined or telescoped with reducers, is
often employed. Antennas of this length require larger ground crews or a cherry picker
for successful installation, and the use of techniques covered in Chap. 29 is appropriate.