Ford 1996 Contour Manual page 136

6
Common Radio Reception Conditions
Several conditions prevent FM reception from being completely
clear and noise-free, such as the following:
Distance/Strength
1.
The strength of the FM signal is directly related to the distance
the signal must travel. The listenable range of an average FM
signal is approximately 25 miles (40 kilometers). Beyond this
distance, the radio is operating in a fringe area and the signal
becomes weaker.
Terrain
2.
The terrain (hilly, mountainous, tall buildings) of the area over
which the signal travels may prevent the FM signal from being
noise-free.
Rounded off frequencies
3.
Some FM radio stations advertise a "rounded-off" frequency
which is not the frequency they actually broadcast on. For
example, a radio station that is assigned a frequency of 98.7
MHz may call itself "Radio 99" even though 99.0 MHz is not an
allowable FM broadcast frequency.
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