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6.
Note about RF performance
6.1.1
Improving Reception
Radio waves travel best in open unobstructed spaces. Aerials work best high
up in open spaces. Unfortunately, it is rarely possible to have both of these
criteria met! However these two statements should be kept in mind when
installing the radio system. This will lead to the best performance of the
system that can be obtained in a given situation. Note that metal objects,
thick and damp walls significantly attenuate radio signals. Reinforced concrete
is a real signal killer as it can act like a metal screen.
If a nearby source of interference contains frequency components in the band
of the system, then the receiver will be desensitised. This is especially true if
the interference is stronger than the signal from a distant transmitter. Typical
sources of interference are mobile phones, walkie-talkie type radios, Tetra
police communication systems, computer equipment (especially older
equipment) and anything with a radio transmitter in it, e.g. the components
of a wireless security system.
6.1.2
Locating the Transmitters
Try to place the transmitter as high up as possible, but not too close to
ceilings. Keep away from damp or metal clad walls, metal objects, cabling,
pipes, etc. Also bear in mind that the fewer obstacles in the path to the
receiver will give the greater range and reliability of the system.
6.1.3
Locating the RC250
The RC250 is a single unit that acts as a data receiver. Locate the RC250
central to the transmitters and clear of sources of radio interference.
Where range is not a problem the built in antenna supplied should be used
and provides a very compact installation. Range can be very significantly
improved using the optional LW-ANT/sma dipole or UHFFlexi/Mag/SMA
antenna. This should be mounted as high as possible and away from sources
of interference.
