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  2. Extremely low frequency - Wikipedia

    en.wikipedia.org/wiki/Extremely_low_frequency

    Extremely low frequency (ELF) is the ITU designation [1] for electromagnetic radiation (radio waves) with frequencies from 3 to 30 Hz, and corresponding wavelengths of 100,000 to 10,000 kilometers, respectively. [2] [3] In atmospheric science, an alternative definition is usually given, from 3 Hz to 3 kHz.

  3. Electromagnetic spectrum - Wikipedia

    en.wikipedia.org/wiki/Electromagnetic_spectrum

    Extremely high frequency: 1 cm: 30 GHz 124 μeV: SHF Super high frequency: 1 dm: 3 GHz 12.4 μeV UHF Ultra high frequency: 1 m: 300 MHz: 1.24 μeV Radio waves: VHF Very high frequency: 10 m 30 MHz 124 neV: HF High frequency: 100 m 3 MHz 12.4 neV MF Medium frequency: 1 km: 300 kHz: 1.24 neV LF Low frequency: 10 km 30 kHz 124 peV: VLF Very low ...

  4. Very low frequency - Wikipedia

    en.wikipedia.org/wiki/Very_low_frequency

    Very low frequency or VLF is the ITU designation [1] for radio frequencies (RF) in the range of 3–30 kHz, corresponding to wavelengths from 100 to 10 km, respectively. The band is also known as the myriameter band or myriameter wave as the wavelengths range from one to ten myriameters (an obsolete metric unit equal to 10 kilometers).

  5. Communication with submarines - Wikipedia

    en.wikipedia.org/wiki/Communication_with_submarines

    Very low frequency (VLF) radio waves can penetrate seawater just over one hundred feet (30 metres), and many navies use powerful shore VLF transmitters for submarine communications. A few nations have built transmitters which use extremely low frequency (ELF) radio waves, which can penetrate seawater to reach submarines at operating depths, but ...

  6. Super low frequency - Wikipedia

    en.wikipedia.org/wiki/Super_low_frequency

    This frequency range includes the frequencies of AC power grids (50 hertz and 60 hertz). Another conflicting designation which includes this frequency range is Extremely Low Frequency (ELF), which in some contexts refers to all frequencies up to 300 hertz.

  7. Schumann resonances - Wikipedia

    en.wikipedia.org/wiki/Schumann_resonances

    The global electromagnetic resonance phenomenon is named after physicist Winfried Otto Schumann who predicted it mathematically in 1952. Schumann resonances are the principal background in the part of the electromagnetic spectrum [2] from 3 Hz through 60 Hz [3] and appear as distinct peaks at extremely low frequencies around 7.83 Hz (fundamental), 14.3, 20.8, 27.3, and 33.8 Hz.

  8. Radio spectrum - Wikipedia

    en.wikipedia.org/wiki/Radio_spectrum

    The radio spectrum is the part of the electromagnetic spectrum with frequencies from 3 Hz to 3,000 GHz (3 THz).Electromagnetic waves in this frequency range, called radio waves, are widely used in modern technology, particularly in telecommunication.

  9. Ultra low frequency - Wikipedia

    en.wikipedia.org/wiki/Ultra_low_frequency

    Ultra low frequency (ULF) is the ITU designation [1] for the frequency range of electromagnetic waves between 300 hertz and 3 kilohertz, corresponding to wavelengths between 1,000 to 100 km. In magnetosphere science and seismology , alternative definitions are usually given, including ranges from 1 mHz to 100 Hz, [ 2 ] 1 mHz to 1 Hz, [ 3 ] and ...