SteppIR BigIR - MK IV Vertical, Инструкция по эксплуатации

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Four radials are what we consider to be the absolute minimum in average soil. How much you
have to gain with a good radial system depends on how good your earth is. Most of us have
poor earth conditions, so the radial system is important. The worse the earth is, the more can
be gained with radials. Graph 2 shows a graph produced by Brian Edward (N2MF) that illus-
trates the relative signal gain you get with the radials and varying length over poor earth. With
better earth, the gain difference between 4 radials and 120 radials will be about 2.5 dB, as op-
posed to 4 dB with poor earth.
If you are restricted to .1 wavelength radials there is not much advantage to using more than
about 24 radials. You can see from Graph 3 that if more radials are used there is a huge advan-
tage to making them longer.
If you cannot lay the radials out in a symmetrical radial pattern, don’t worry too much - it will
distort your omni-directional pattern slightly but won’t reduce your efficiency very much. Lay
the radials out in the best manner possible given your situation. There are various ways to ac-
complish laying a radial system, including turning corners, etc. Good results are limited only to
your creative energy and determination! Be aware that very high voltages can exist at the ends
of radials, so be certain that no one can come into contact with them. It is a good idea to use
insulated wire to protect from corrosion, and don’t bury the radials any deeper than necessary,
one to three inches is sufficient.
Graph 3
Graph 2
Number of Radials (N)
S
u
ff
ic
ie
n
t R
a
d
ia
l L
e
n
g
th
(
w
a
v
e
le
n
g
th
)
0 15 30 45 60 75 90 105 120
0
0.08
0.16
0.24
0.32
0.4
0.48
Number of radials
120 Radials
Radil Length in Wave length
R
e
la
ti
v
e
G
a
in
0 0.06 0.12 0.18 0.24 0.3 0.36 0.42 0.48 0.54 0.6
-1.2
-0.6
0
0.6
1.2
1.8
2.4
3
3.6
N=48
N=12
N=24
N=4
N=120
N=96
Radial length in wavelength
96 Radials
48 Radials
24 Radials
12 Radials
4 Radials
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