Installation Notes - Icom IC-7000 Instruction Manual

21
ABOUT CE

INSTALLATION NOTES

Fo r a m a t e u r b a s e s t a t i o n i n s t a l l a t i o n s i t i s
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 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 antenna
may be physically short in terms of electrical length
and that the installation will require some antenna
matching device which can create local, high intensity
magnetic fields. 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. The EC recommended
limits are almost identical to the FCC specified
'uncontrolled' limits and tables exist 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
radiation pattern is forwards and that radiation
ver tically 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
constant carrier.
For the bands 10 MHz and higher the following power
density limits have been recommended:
10–400 MHz
435 MHz 2.2 W/sq m
153
2 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
10 2.8 m 2.7 m
25 3.4 m 3.3 m
100 5 m 4.7 m
1000 12 m 11.5 m
Forward clearance, EIRP by frequency band
Watts 10–2 m 70 cm 23 cm 13 cm and above
100 2 m 2 m
1,000 6.5 m 6 m
10,000 20 m 18 m
100,000 65 m 60 m
In all cases any possible risk depends on the
transmitter being activated for long periods. (actual
recommendation 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.
Versions of the IC-7000 which display the
"CE" symbol on the serial number label,
comply with the essential requirements of
the European Radio and Telecommunication
Terminal Directive 1999/5/EC.
This warning symbol indicates that this
equipment operates in non-harmonised
frequency bands and/or may be subject to
licensing conditions in the country of use.
Be sure to check that you have the correct
ve r s i o n o f t h i s r a d i o o r t h e c o r r e c t
programming of this radio, to comply with
national licensing requirement.
2 m 2 m
2.5 m 2.3 m
2.7 m 2.5 m
3.6 m 3.2 m
7.3 m 6.3 m
1.1 m 0.7 m
3.5 m 3 m
11 m 7 m
35 m 29 m