11. Transmission range
Ranges and disturbances
• The product works in the 868MHz range which is also used by other radio
services. This is why there may be a restrictive operation and range due
to devices that work on the same or a neighboring frequency.
• The specified range of up to 100m is the so-called free field range, i.e. the
range within visible contact between the transmitter and receiver. But in
practice, walls, ceilings etc. between the transmitter and receiver may
affect and reduce the range.
Other causes for reduced range:
• High frequency interferences of all sorts
• Any kind of housing and vegetation
• Cables and conductive metal parts which are located near the devices
or within or near their transmission path, e.g. heaters, metallized insula-
tion glass windows, reinforced concrete ceilings etc.
• There is an influence on the radiation pattern of antennas due by the
distance from transmitter or receiver to conductive surfaces or objects
(to human bodies or ground also)
• Broadband interference in urban areas which reduces the signal-to-
noise-ratio; the signal will no longer be recognized due to this "noise".
• Interference radiation resulting from insufficiently shielded electronics
e.g. turned on computers or the like.
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