Installation Notes - Icom ic-718 Instruction Manual

For amateur base station installations, it is
recommended that the forwards clearance in front of
the antenna array is calculated relative to the EIRP
(Effective Isotropic Radiated Power). The clearance
height below the antenna array can be determined in
most cases from the RF power at the antenna input
terminals.
As different exposure limits have been recommended
for different frequencies, a relative table shows a
guideline for installation considerations.
Below 10 MHz, the recommended limits are specifi ed
in terms of V/m or A/m fi elds as they are likely to fall
within the near-fi eld region. Similarly, at antennae may
be physically short in terms of electrical length and that
the installation will require some antenna matching de-
vice which can create high intensity magnetic fi elds.
Analysis of such MF installations is best considered in
association with published guidance notes such as the
FCC OET Bulletin 65 Edition 97-01 and its annexes
relative to amateur transmitter installations. Further in-
formation can be found at http://www.arrl.org/
• Typical amateur radio installation
Exposure distance assumes that the predominant ra-
diation pattern is forwards and that radiation vertically
downwards is at unity gain (sidelobe suppression is
equal to main lobe gain). This is true of almost every
gain antenna today. Exposed persons are assumed
to be beneath the antenna array and have a typical
height to 1.8 m.
The fi gures assume the worst case emission of con-
stant carrier.
For the bands 10 MHz and higher the following power
density limits are recommended :
10–30 MHz 2 W/sq m
Watts (EIRP)/ Clearance heights
1 2.1 (m)
10 2.8
25 3.4
100 5
1000 12
Watts (EIRP)/ Forward clearance
100 2 (m)
1,000 6.5
10,000 20
100,000 65

INSTALLATION NOTES

In all cases any possible risk depends on the transmit-
ter being activated for long periods. (actual recommen-
dation limits are specifi ed as an average of 6 minutes)
Normally the transmitter is not active for long periods
of time. Some radio licenses will require that a timer
circuit automatically cuts the transmitter after 1–2 min-
utes etc.
Similarly some types of transmitter, SSB, CW, AM,
etc. have a lower 'average' output power and the per-
ceived risk is even lower.
List of Country codes (ISO 3166-1)
Country Codes
1 Austria AT
2 Belgium BE
3 Bulgaria BG
4 Croatia HR
5 Czech Republic CZ
6 Cyprus CY
7 Denmark DK
8 Estonia EE
9 Finland FI
10 France FR
11 Germany DE
12 Greece GR
13 Hungary HU
14 Iceland IS
15 Ireland IE
16 Italy IT
17 Latvia LV
Version and Frequency coverage
EUR (#43)
Tx
1.800000 – 1.999999
3.500000 – 3.800000
7.000000 – 7.100000
10.100000 – 10.150000
14.000000 – 14.350000
18.068000 – 18.168000
21.000000 – 21.450000
24.890000 – 24.990000
28.000000 – 29.700000
14
Country Codes
18 Liechtenstein LI
19 Lithuania LT
20 Luxembourg LU
21 Malta MT
22 Netherlands NL
23 Norway NO
24 Poland PL
25 Portugal PT
26 Romania RO
27 Slovakia SK
28 Slovenia SI
29 Spain ES
30 Sweden SE
31 Switzerland CH
32 Turkey TR
33 United Kingdom GB
Rx
0.500000 – 29.999999
(Unit: MHz)
59