Ultra low frequency
Encyclopedia : U : UL : ULT : Ultra low frequency
| ultra low frequency (ULF) |
|---|
| Cycles per second: 300Hz to 3000Hz Wavelength: 1000km to 100km |
Ultra Low Frequency (ULF) is the frequency range between 300 hertz and 3000 hertz. This band is used for communications in mines, as it can penetrate the earth. http://www.weather.nps.navy.mil/~psguest/EMEO_online/module3/module_3_1.html
Earthquakes
Some monitoring stations have reported that earthquakes are sometimes preceded by a spike in ULF activity. A remarkable example of this occurred before the Loma Prieta Earthquake in California in 1989. Researchers are attempting to learn more about this correlation to find out whether this method can be used as part of an early warning system for earthquakes.See also
References
External articles
- Tomislav Stimac, "[Definition of frequency bands (VLF, ELF... etc.)]". IK1QFK Home Page (vlf.it).
- [NASA live streaming ELF -> VLF Receiver]
| Radio spectrum | ||||||||||
| ELF | SLF | ULF | VLF | LF | MF | HF | VHF | UHF | SHF | EHF |
| 3 Hz | 30 Hz | 300 Hz | 3 kHz | 30 kHz | 300 kHz | 3 MHz | 30 MHz | 300 MHz | 3 GHz | 30 GHz |
| 30 Hz | 300 Hz | 3 kHz | 30 kHz | 300 kHz | 3 MHz | 30 MHz | 300 MHz | 3 GHz | 30 GHz | 300 GHz |
| The Electromagnetic Spectrum (Sorted by wavelength, short to long) Gamma ray | X-ray | Ultraviolet | Visible spectrum | Infrared | Terahertz radiation | Microwave | Radio waves
Visible (optical) spectrum: Violet | Blue | Green | Yellow | Orange | Red
Microwave spectrum: W band | V band | K band: Ka band, Ku band | X band | C band | S band | L band
Radio spectrum: EHF | SHF | UHF | VHF | HF | MF | LF | VLF | ULF | SLF | ELF
Wavelength designations : Microwave | Shortwave | Mediumwave | Longwave
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