SteppIR BigIR - Page 38

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For more detailed information on ground mounted and elevated mounted radial setups, please read
our complete white paper on radials:
https://consumer.steppir.com/wp-content/uploads/2018/11/Radial-Systems-for-Elevated-and-Ground
-Mounted-Antennas-2.2-12_2018.pdf
COUNTERPOISE/RADIAL SYSTEM OVERVIEW
Ground Mounting:
If you choose to ground mount the vertical, pick a spot that will allow you the best chance of spreading
your radials evenly around the antenna, and away from trees and other objects if possible. You will need
to determine how much effort and wire you are willing to invest in this installation. The tradeoffs are as
follows:
1. More radials equals higher efficiency (see Graph 1)
2. Match your radial length to the number of radials using Graph 2, why waste wire
3. If only a few radials can be used (8 or less) do not make them excessively long, it can reduce gain
4. A vertical antenna is only as good as its radials, as the counterpoise is literally half of the system. 25
– 30 is about where diminishing returns begin, the minimum recommended is 16.
Graph 1
Number of Radials
% Efficiency
0 15 30 45 60 75 90 105 120
0
20
40
60
80
100
Number of radials
Graph 2
120 Radials
Radil Length in Wave length
Relative Gain
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