30 lines
1.3 KiB
Markdown
30 lines
1.3 KiB
Markdown
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---
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tags: [radio, ham-study]
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---
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# The difference between frequency and bandwidth
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Think of a radio transmission as being like a lane on the motorway. The
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frequency is the specific motorway that you are travelling on. A frequency like
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95.8 is the "center frequency".
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In fact, a licensed radio station has a range of frequencies at its disposal.
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These other frequencies exist around the center frequency. The total available
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frequencies constitute the station's bandwidth.
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The different frequencies are like different lanes on the motorway. Not all of
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the data will be transmitted on the center frequency. Nearby frequencies will
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also be used such as 95.7, for example.
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When you tune to 95.8 you are not only tuning to that frequency, you are tuning
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to it as the center frequency encompassing the other frequencies.
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[FM](./Frequency_modulation.md) has 200kHz bandwidth per station whereas AM has
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much less bandwidth resulting in poorer sound quality. An FM station can use the
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additional frequencies to transmit sound in stereo, for example.
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A radio receiver is designed to process the data accross the frequency spectrum
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for the station and unify it into a reconstruction of the original audio signal.
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The more information you want to transmit, the more "lanes" or bandwidth you
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require.
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