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Radio frequency, or RF, refers to that portion of the electromagnetic spectrum in which electromagnetic waves can be generated by alternating current fed to an antenna. Such frequencies and the belonging wavelength account for the following parts of the spectrum shown in the table below.
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Radio frequency spectrum
Notes
Above 300 GHz, the absorption of electromagnetic radiation by Earth's atmosphere is so great that the atmosphere is effectively opaque to higher frequencies of electromagnetic radiation, until the atmosphere becomes transparent again in the so-called infrared and optical window frequency ranges.
The ELF, SLF, ULF, and VLF bands overlap the AF (audio frequency) spectrum, which is approximately 20–20,000 Hz. However, sounds are transmitted by atmospheric compression and expansion, and not by electromagnetic energy.
Another note of merit is that all objects have their own radio frequency, no matter how minute.
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General
Broadcast Frequencies:
AM Radio = 535kHz - 1605kHz (MF)
TV Band I (Channels 2 - 6) = 54MHz - 88MHz (VHF)
FM Radio Band II = 88MHz - 108MHz (VHF)
TV Band III (Channels 7 - 13) = 174MHz - 216MHz (VHF)
TV Bands IV & V (Channels 14 - 69) = 470MHz - 806MHz (UHF) *
For more information see the NTIA frequency allocation chart: http://www.ntia.doc.gov/osmhome/allochrt.html
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Amateur radio frequencies
The range of allowed frequencies vary between countries. These are just some of the more common bands. In the article about amateur radio is another list.
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IEEE US
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EU, NATO, US ECM Frequency Designations
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See also
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