6 ABOUT CE
• Typical installation exampleA UHF base station transmitter is to be installed on the roof of an office.
The transmit power is 25 watts, there is 20 m of
The specification of the
The RF power at the antenna input will be 12.5 watts.
The dipole antenna has a forward gain of 0 dBd or 1.6, giving an EIRP of 20 watts.
Referring to the table above for VHF/UHF vertical antennas, this gives a front clearance distance of ap- prox. 1.5 m and a height clearance of 3 m.
The antenna installation needs to ensure that the lowest part of the antenna is at least 3 m above any point where the general public may gain access and that they cannot pass within 1.5 m in front of the antenna.
If there is no general public access to the roof in question then the antenna could be mounted on a short stub mast. If there is such access to the roof then the antenna could be mounted on top of a short mast of 3.2 m high. The mast position should be such that the antenna can radiate clearly i.e. no other object or structure is within 1.5 m (preferably more).
It should be relatively easy to fulfil all these recom- mendations.
If for any reason such minimum distances are impossible to guarantee then some type of access control fence or barrier around the antenna installation should be provided.
Should a Yagi type antenna be used then you will have to obtain a 3 dimensional polar plot of the radiation characteristic from the manufacturer and evaluate the clearance distances in both vertical and horizontal planes.
All of the above comments on RF safety assume that the radio is transmitting continuously in a constant carrier mode such as FM or RTTY etc.
The RF exposure limits recommended by the EC are based on the mean power averaged over a 6 minute period.
Therefore if the total transmit time during any 6 minute period is reduced, then the installation will be even further within the recommended limits.
CE Versions of the
This warning symbol indicates that this equipment operates in
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1 | Austria | AT | 18 | Liechtenstein | LI |
2 | Belgium | BE | 19 | Lithuania | LT |
3 | Bulgaria | BG | 20 | Luxembourg | LU |
4 | Croatia | HR | 21 | Malta | MT |
5 | Czech Republic | CZ | 22 | Netherlands | NL |
6 | Cyprus | CY | 23 | Norway | NO |
7 | Denmark | DK | 24 | Poland | PL |
8 | Estonia | EE | 25 | Portugal | PT |
9 | Finland | FI | 26 | Romania | RO |
10 | France | FR | 27 | Slovakia | SK |
11 | Germany | DE | 28 | Slovenia | SI |
12 | Greece | GR | 29 | Spain | ES |
13 | Hungary | HU | 30 | Sweden | SE |
14 | Iceland | IS | 31 | Switzerland | CH |
15 | Ireland | IE | 32 | Turkey | TR |
16 | Italy | IT | 33 | United Kingdom | GB |
17 | Latvia | LV |
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