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INSTALLATION NOTES
For amateur base station installations it is recommend-
ed that the forwards clearance in front of the antenna
array is calculated relative to the EIRP (Effective Iso-
tropic 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 speci-
fied in terms of V/m or A/m fields as they are likely
to fall within the near-field region. Similarly, the an-
tennae may be physically short in terms of electrical
length and that the installation will require some an-
tenna matching device which can create local, high in-
tensity magnetic fields. Analysis of such MF installa-
tions is best considered in association with published
guidance notes such as the FCC OET Bulletin 65 Edi-
tion 97-01 and its annexes relative to amateur trans-
mitter installations. The EC recommended limits are al-
most identical to the FCC specified ‘uncontrolled’ limits
and tables exist that show pre-calculated safe distanc-
es for different antenna types for different frequency
bands.Furtherinformationcanbefoundathttp://www.
arrl.org/.
• Typical amateur radio installation
Exposure distance assumes that the predominant ra-
diation pattern is forwards and that radiation vertical-
ly 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 figures assume the worst case emission of con-
stant carrier.
For the bands 10 MHz and higher the following power
densitylimitshavebeenrecommended:
10–400 MHz 2 W/sq m
435 MHz 2.2 W/sq m
1296 MHz 6.5 W/sq m
EIRP Clearance heights by frequency band
Watts 10–2 m 70 cm 23 cm 13 cm and above
1 2.1 m 2 m 2 m 2 m
10 2.8 m 2.7 m 2.5 m 2.3 m
25 3.4 m 3.3 m 2.7 m 2.5 m
100 5 m 4.7 m 3.6 m 3.2 m
1000 12 m 11.5 m 7.3 m 6.3 m
Forward clearance, EIRP by frequency band
Watts 10–2 m 70 cm 23 cm 13 cm and above
100 2 m 2 m 1.1 m 0.7 m
1000 6.5 m 6 m 3.5 m 3 m
10,000 20 m 18 m 11 m 7 m
100,000 65 m 60 m 35 m 29 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 the transmitter after 1–
2 minutes etc.
Similarly some types of transmitter, SSB, CW, AM etc.
have a lower ‘average’ output power and the assessed
risk is even lower.
VersionsoftheIC-910Hwhichdisplaythe“CE”
symbol on the serial number seal, comply with
the essential requirements of the European
Radio and Telecommunication Terminal Direc-
tive 1999/5/EC.
This warning symbol indicates that this equip-
ment operates in non-harmonised frequency
bands and/or may be subject to licensing condi-
tions in the country of use. Be sure to check
that you have the correct version of this radio or
the correct programming of this radio, to com-
ply with national licensing requirement.
• 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
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
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