Icom IC-7200 Instruction Manual page 47

FOR EUROPEAN VERSIONS
• Installation Notes
For amateur base station installations it is recom-
mended that the forward clearance in front of the an-
tenna 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 recommend-
ed for different frequencies, a relative table shows a
guideline for installation considerations.
Below 30 MHz, the recommended limits are specified
in terms of V/m or A/m fields as they are likely to fall
within the near-field region. Similarly, the antennas
may be physically short in terms of electrical length
and that the installation will require some antenna
matching device which can create local, high inten-
sity magnetic fields. Analysis of such MF installations
is best considered in association with published guid-
ance notes such as the FCC OET Bulletin 65 Edition
97-01 and its annexes relative to amateur transmitter
installations.
The EC recommended limits are almost identical to
the FCC specified 'uncontrolled' limits and tables ex-
ist that show pre-calculated safe distances for different
antenna types for different frequency bands. Further
information can be found at http://www.arrl.org/.
• Typical amateur radio installation
Exposure distance assumes that the predominant ra-
diation pattern is forward 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 of 1.8 m.
The figures assume the worst case emission of a con-
stant carrier.
For the bands 10 MHz and higher the following power
density limits have been recommended:
10–50 MHz 2 W/sq m
Vertical clearance by EIRP output
1 Watts 2.1 m
10 Watts 2.8 m
25 Watts 3.4 m
100 Watts 5 m
1000 Watts 12 m
Forward clearance by EIRP output
100 Watts 2 m
1000 Watts 6.5 m
10,000 Watts 20 m
100,000 Watts 65 m
In all cases any possible risk depends on the trans-
mitter being activated for long periods. (actual recom-
mendation limits are specified as an average during 6
minutes) Normally the transmitter is not active for long
periods of time. Some radio licenses will require that a
timer circuit automatically cuts off the transmitter after
1–2 minutes or so.
Similarly some modes of transmission, like SSB, CW
and AM, have a lower 'average' output power and the
assessed risk is even lower.
• Country codes List
Country Codes
1 Austria AT
2 Belgium BE
3 Bulgaria BG
4
Croatia HR
5 Czech Republic CZ
6 Cyprus CY
7 DK
Denmark
8 Estonia EE
9 FI
Finland
10 FR
France
11 DE
Germany
12 GR
Greece
13 HU
Hungary
14 IS
Iceland
15 IE
Ireland
16 IT
Italy
17 LV
Latvia
(ISO 3166-1)
Country Codes
18 Liechtenstein LI
19 LT
Lithuania
20 Luxembourg LU
MT
21 Malta
22 NL
Netherlands
23 Norway NO
24 PL
Poland
25 PT
Portugal
26 RO
Romania
27 SK
Slovakia
28 SI
Slovenia
29 ES
Spain
SE
30
Sweden
31 CH
Switzerland
32 TR
Turkey
33 GB
United Kingdom
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
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