- Super low frequency
radioservices Seafarer (USA) on 76 hertz and ZEVS( Russia) on 82 hertz operate in this range, which is often incorrectly called Extremely Low Frequency(ELF). They both provide communication services for submarines at a certain depth.
sound cards are increasingly being used instead of radio receivers for this frequency range, because of their much smaller size and lower cost. Signals received by the sound card with a coil or a wire antenna are analysed by a software Fast Fourier Transform algorithmand converted into audible sound. [ cite web | url=http://www.vlf.it/ | title=Radio waves below 22 kHz ]
Communication with submarines
* Tomislav Stimac, " [http://www.vlf.it/frequency/bands.html Definition of frequency bands (VLF, ELF... etc.)] ". IK1QFK Home Page (vlf.it).
* [http://spaceweather.com/glossary/inspire.html NASA live streaming ELF -> VLF Receiver]
Wikimedia Foundation. 2010.
Look at other dictionaries:
super low frequency — noun any radiofrequency between 30 and 300 hertz. Abbrev.: SLF … Australian English dictionary
Super basse frequence — Super basse fréquence On appelle super basse fréquence (SLF), Super low frequency en anglais, la bande de radiofréquences qui s étend de 30 à 300 Hz (longueur d onde de 10 000 à 1000 km). Ces fréquences incluent les rayonnements des… … Wikipédia en Français
Super basse fréquence — On appelle super basse fréquence (SLF), Super low frequency en anglais, la bande de radiofréquences qui s étend de 30 à 300 Hz (longueur d onde de 10 000 à 1000 km). Ces fréquences incluent les rayonnements des réseaux électriques à 50… … Wikipédia en Français
Super Hi-Vision — Super Hi Vision, also known as Ultra High Definition Video, UHDV, Ultra High Definition Television, UHDTV and UHD is an experimental digital video format, currently proposed by NHK of Japan, the BBC, and RAI. Super Hi Vision s main specifications … Wikipedia
Super Audio CD — Media type Optical disc Encoding Digital (DSD) Capacity up to 7.95 GiB/GB … Wikipedia
Super-resolution — (SR) are techniques that in some way enhance the resolution of an imaging system. There are different views as to what is considered an SR technique: some consider only techniques that break the diffraction limit of systems, while others also… … Wikipedia
Super Video CD — Compact Disc Super Video (SVCD) Media type Optical disc … Wikipedia
Super Girl (contest) — This article is about the singing contest. For other uses, see Supergirl (disambiguation). Super Girl 超级女声 (2004 2006) 快乐女声 (2009 2011) Super Girl logo Also known as Super Voice Girls Genre … Wikipedia
Low Probability of Intercept Radar — A Low Probability of Intercept Radar (LPIR) is designed to be difficult to detect by passive radar detection equipment (such as a radar warning receiver RWR) while it is searching for a target or engaged in target tracking. This characteristic is … Wikipedia
Radio-frequency identification — (RFID) is a technology that uses radio waves to transfer data from an electronic tag, called RFID tag or label, attached to an object, through a reader for the purpose of identifying and tracking the object. Some RFID tags can be read from… … Wikipedia