166nCar radio reception
Safety belt tensioner
The AM frequency bands (medium- The safety belt tensioner responds to
wave, long-wave and short-wave) make severe collisions by tightening the belts
it possible to receive stations from a to ensure that occupants remain firmly
great distance, because the broadcast positioned in their seats. A gas-pres-
signals travel not only along the ground sure system retracts the buckle
as surface waves, but also as atmo-
spheric waves that are reflected from
the ionosphere.
assembly to tension the shoulder and
lap belts within fractions of a second.
This tends to further reduce the
tendency to slide under the lap belt.
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.
The limitations which are inherent to
radio reception in a moving vehicle
have been minimized by the use of
innovative systems.
English 