Interior Features; Audio System- Page 280

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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 reflect. 

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.

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2015/05/11   14:01:23