Dodge 2007 Caliber - Manual (Page 161)

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.
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.
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 6 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.
ELECTRONIC DIGITAL CLOCK
The clock and radio each use the display panel built into
the radio. A digital readout shows the frequency and/or
time in hours and minutes (depending on your radio
model) whenever the ignition switch is in the “ON” or
“ACC” position.
When the ignition switch is in the “OFF” position, or
when the radio frequency is being displayed, time keep-
ing is accurately maintained.
On the AM/FM/CD (6-disc) radio the time button alter-
nates the location of the time and frequency on the
display. On the AM/FM/CD (single-disc) radio only one
of the two, time or frequency is displayed.
UNDERSTANDING YOUR INSTRUMENT PANEL 161
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