Super low frequency


Super low frequency

Super Low Frequency (SLF) is the frequency range between 30 hertz and 300 hertz. This frequency range includes the frequencies of AC power grids (50 hertz and 60 hertz).

The radio services 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.

PCs with 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 algorithm and converted into audible sound. [ cite web | url=http://www.vlf.it/ | title=Radio waves below 22 kHz ]

ee also

*Communication with submarines

External articles

* 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]

References


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