Interior Features; Audio System- Page 276

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Interior Features

Audio System

  Do not spill any liquid on the audio 
system.

  Do not insert any objects, other than CDs, 
into the slot.

 Radio  Reception

    AM  characteristics

    AM signals bend around such things as 
buildings or mountains and bounce off the 
ionosphere.
  Therefore, they can reach longer distances 
than FM signals.
  Because of this, two stations may 
sometimes be picked up on the same 
frequency at the same time.

Station 2

Station 1

Ionosphere

  FM  characteristics

    An FM broadcast range is usually about 
40—50 km (25—30 miles) from the 
source. Because of extra coding needed to 
break the sound into two channels, stereo 
FM has even less range than monaural 
(non-stereo) FM.

FM Station

40—50km
(25—30 miles)

  Signals from an FM transmitter are similar 
to beams of light because they do not 
bend around corners, but they do refl ect. 
Unlike AM signals, FM signals cannot 
travel beyond the horizon. Therefore, FM 
stations cannot be received at the great 
distances possible with AM reception.

AM wave

FM wave

FM wave

100—200 km (60—120 miles)

Ionosphere

  Atmospheric conditions can also affect 
FM reception. High humidity will cause 
poor reception. However, cloudy days may 
provide better reception than clear days.