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14. Information on the range
Ranges and interference
• The activation switch uses the 868MHz range, which is also used by other
radio services. Therefore devices that operate on the same or neighbouring
frequencies may restrict both its operation and its range.
• The specified range of 300m is the free-field range, which means the range
with visual contact between the transmitter and receiver. In practice,
however, ceilings, walls, garages or neighbouring buildings between the
transmitter and the receiver may affect and reduce the range accordingly.
• The range also depends on the version of the available alarm base station.
Earlier versions of the alarm base station had a range of up to 100m; for
others, an external antenna ('FAZ-HF') permitted larger ranges.
• The actual attainable distance between the transmitter and the receiver in
normal operation greatly depends on the installation location and the
surroundings.
As a rule – when mounted in a family home, for example – all the components
should work properly and there should be no radio reception problems.
Other causes of reduced ranges:
• All types of high-frequency interference
• Any buildings or vegetation
• Conductive metal parts that are located near the devices or within or near
their transmission path, for example, radiators, metallised insulation glass
windows, reinforced concrete ceilings and so on
• Influence on the radiation pattern of antennas due to the distance from the
transmitter or receiver to conductive surfaces or objects (also to human
bodies or the ground)
• Broadband interference in urban areas that reduces the signal-to-noise ratio;
the signal is no longer recognised due to this 'noise'
• Interference radiation resulting from insufficiently shielded electronic
devices, for example, operating computers or similar
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