Radio General Information; Radio Broadcast Signals; Two Types Of Signals; Electrical Disturbances - Jeep 2008 Liberty Owner's Manual

RADIO GENERAL INFORMATION

Radio Broadcast Signals

Your new radio will provide excellent reception under
most operating conditions. Like any system, however, car
radios have performance limitations, due to mobile op-
eration and natural phenomena, which might lead you to
believe your sound system is malfunctioning. To help
you understand and save you concern about these "ap-
parent" malfunctions, you must understand a point or
two about the transmission and reception of radio sig-
nals.

Two Types of Signals

There are two basic types of radio signals... AM (Ampli-
tude Modulation), in which the transmitted sound causes
the amplitude, or height, of the radio waves to vary... and
FM (Frequency Modulation), in which the frequency of
the wave is varied to carry the sound.
INSTRUMENT PANEL AND CONTROLS 221

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: For vehicles not equipped with the Electronic
Vehicle Information Center (EVIC), the radio and steering
wheel radio controls (if equipped) will remain active for
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