FAW Jilin Automobile Xenia S80, Руководство пользователя

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7-39
Service coverage of FM broadcast
Transmitting antenna of 9m in height
Effective radiated power of 1kw
21km (FM stereo car-borne radio)
50km (FM single-track car-borne radio)
101km (domestic stereophonic receiver)
(The clear coverage indicated in the figure above is acquired from flat country free of
obstacles. The range may also vary if the power and ground conditions are different)
Fade
FM radio signals may be suddenly deteriorated in
some places, which is referred to as "fading".
Fading refers to a type of radio-signal loss
phenomena. For example, radio signals behind the
obstacles such as buildings and columns may be
extremely minor. The antenna may fail to receive
radio signals when your automobile pass through
those places, and interference sound “cheep cheep”
may be given. That is exactly the inherent
characteristics of FM radio signals, which is caused
by the unique transmittal mode. That phenomenon
cannot be avoided.
When you receive FM broadcast at home, you may
still listen to gem-pure FM broadcast if you extend
the antenna to a higher position or use antenna with
high sensitivity even if the radio signals were
extremely minor.
On the other hand, if you use the car-borne radio to
receive FM broadcast when you drive your
automobile, a lot of limiting factors such as shape
and mounting position of antenna, and the engine
noises etc. may have adverse impact upon the
broadcasting reception.
Therefore, as compared with listening to broadcast
at home, the area allowing you to receive clear
broadcast may get narrow.