Electrical Disturbances
Radio waves may pick up electrical disturbances during
transmission. They mainly affect the wave amplitude,
and thus remain a part of the AM reception. They
interfere very little with the frequency variations that
carry the FM signal.
TWO TYPES OF SIGNALS
There are two basic types of radio signals: AM or
Amplitude Modulation, in which the transmitted sound
causes the amplitude, or height, of the radio waves to
vary; and FM or Frequency Modulation, in which the
frequency of the wave is varied to carry the sound.
AM Reception
AM sound is based on wave amplitude, so AM reception
can be disrupted by such things as lightning, power lines
and neon signs.
FM Reception
Because FM transmission is based on frequency varia-
tions, interference that consists of amplitude variations
can be filtered out, leaving the reception relatively clear,
which is the major feature of FM radio.
NOTE:The radio, steering wheel radio controls (if
equipped), and six-disc CD/DVD changer (if equipped)
will remain active for up to 10 minutes after the ignition
switch has been turned OFF. Opening a vehicle front
door will cancel this feature.
210 UNDERSTANDING YOUR INSTRUMENT PANEL
SALES CODE REC Ð AM/FM/CD (6±DISC) RADIO
WITH NAVIGATION SYSTEM
Satellite Navigation Radio with CD Player with MP3
Capability (REC) - combines a Global-Positioning
System-based navigation system with an integrated color
screen to provide maps, turn identification, selectionmenus and instructions for selecting a variety of destina-
tions and routes, AM/FM stereo radio and six-disc CD
changer with MP3 capability.
Mapping information for navigation is supplied on a
DVD that is loaded into the unit. One map DVD covers
all of North America. Refer to your ªNavigation User's
Manualº for detailed operating instructions.
Operating Instructions Ð Satellite Radio Ð If
Equipped
Refer to your ªNavigation User's Manualº for detailed
operating instructions.
REC Setting the Clock
GPS Clock
The GPS receiver used in this system is synchronized to
the time data being transmitted by the GPS satellites. The
satellites' clock is Greenwich Mean Time (GMT). This is
248 UNDERSTANDING YOUR INSTRUMENT PANEL
