BMW x5 2000 Manual Do Utilizador

178

Radio reception

Safety belt tensioner

Radio waves — mediumwave, long-
wave and shortwave — offer a wide
range of reception, because the broad-
cast signals travel not only along the
ground as surface waves, but also as
waves bounced back to earth from the
ionosphere.
Frequency-modulation (FM) provides
substantially better sound quality than
AM. However, because FM transmis-
sions rely on line-of-sight broadcast
waves, their effective reception range is
limited.

360de084

Although numerous factors combine to
impose inherent limitations on the re-
ception quality available from mobile
radios, specially designed systems can
be employed to minimize their effects:

The Diversity Antenna system employs
several FM antennas integrated within
the rear window. An integral processor
automatically selects the antenna with
the best FM reception quality at any
given time. Because the ongoing an-
tenna selection process is completed
within milliseconds, it remains inaudible
to the radio listener.

The safety belt tensioner responds to
collisions by tightening the belts to en-
sure that occupants remain firmly posi-
tioned in their seats. A gas-pressure
system retracts the buckle assembly to
tension the shoulder and lap belts
within fractions of a second. This re-
duces the tendency to slide under the
lap belt.

390de330