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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 account for the following parts of the spectrum shown in the table below.


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.

The SHF and EHF bands are often considered to be not part of the Radio Spectrum and form their own Microwave Spectrum .


NAMED FREQUENCY BANDS



General

Broadcast Frequencies:
  • AM Radio = 535kHz - 1605kHz (LF)

  • 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) = 512MHz - 806MHz (UHF)


For more information see the NTIA frequency allocation chart: http://www.ntia.doc.gov/osmhome/allochrt.html


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.


IEEE US



EU , NATO





SEE ALSO




EXTERNAL LINKS

  • [http://www.sengpielaudio.com/calculator-wavelength.htm Radio and light waves conversion:



REFERENCES