Auroral Chorus V: Sferics Anthology & Radio DX

* Auroral Chorus V: Sferics Anthology & Radio DX -- 1989 to 2020 * This page contains ongoing natural ELF-VLF radio recordings and also other "DX" radio recordings in mono and stereo between 1989 throughout 2020, by Stephen P. McGreevy - N6NKS. All of the ELF-VLF recordings pertain to lightning "atmospherics" or "sferics" as lightning is a huge part of natural ELF-VLF radio emissions in the AudioBand. Many of the radio-DX recordings 2015 to 2020 also contain lightning-impulse "static" in them as well: (lightning-stroke energy is very "broadband" - i.e. from "DC to Light"). Our planet Earth is alive with this vast amount of natural-electricity in the form of lightning stroke/strike electromagnetic emissions and these can also be considered "primordial radio emissions." Every lightning bolt within 3,000 miles or about 5,000 km of the VLF receiver creates a pop or a crackle in a VLF receiver's audio output, especially at these AUDIO-frequency radio-waves. Because lightning storms produce vast amounts of radio energy at VLF frequencies, the World-Wide Lightning Location Network (wwlln.net) employs VLF receivers to direction-find and map lightning strokes via the very VLF signals presented herein. The majority of natural VLF radio audio files on this page are in STEREO employing my WR-9STL dual-loop receiver. In the stereo (dual-loop/orthogonally-oriented) natural VLF radio recordings on this page, you can hear the directionality of the two VLF-loop antennas and the stereo-effects because of the differing directions that all of the lightning "sferics" are originating from - whether cloud-to-cloud lightning (sometimes creating multi-burst lightning strings), to clear pops of ground strikes. Maybe many of the lightning bolts making a sferic also launch Sprites toward the ionosphere! I am fascinated by lightning and associated electromagnetic-emissions of lightning (and they spawn whistlers occasionally, too) as much as the other sounds of Earth's natural-VLF-radio phenomena such as whistlers and dawn-chorus. Lightning static - also called "atmospherics" or "sferics" - can be interesting to listen to, and I am undertaking the project of stereophonic recording of lightning sferics with a dual, cross-azimuth loop-antenna receiving system. The sounds of sferics in stereo are quite beautiful! A particularly beautiful stereo tweek/whistler recording is the 33 minute track/23 August 2012/0745UT file (recorded in Inyo County, California) to the right or downloadable links below. What causes the "ringyness" or "pingyness" of lightning atmospherics/sferics (at nighttime) is caused by the lowest layers of the ionosphere and Earth's surface and also Ocean surfaces forming a kind-of "waveguide" that enhances the approximately 1.7 kHz (+/- 200 Hz) audio-frequencies of these electromagnetic signals. They are called "Tweeks." (They are not EQ signals as some have assumed). Tweeks can always sound pretty and enjoyable when other VLF emissions from up farther within the Magnetosphere fail to occur. Like raindrops on a rooftop, the sounds of Tweeks can be soothing to some. Whistlers are precipitated by lightning strokes as you will hear in all of these amazing and beautiful recordings. Enjoy! In March 2015 I uploaded several tracks that contain compilation-edits of various natural VLF radio field-recording expeditions to locations in Canada and Alaska within the auroral-zone (where aurora are most frequently visible). Auroral-zone locations of Earth can be considered "VLF hot-spots." ----- Update October 2016: I have uploaded several California-desert medium-wave DX files (in addition to other interesting MF-HF DXing files) of STEREO broadband MW/AM band DX made either via 2 independent wire antennas or 2 orthogonal/cross-azimuth 7-turn deltoid-loops - the audio-sounds of this MW/AM diversity-reception is amazing! This new receiver is based upon two TA7642 AM radio ICs. (bandwidth of each receiver channel occupies 3 to 4 BCB channels (i.e. about 40-50 kHz wide). See enclosed photos on this page - links to the right. SpM 07 October 2016. ----- Stephen P. McGreevy - N6NKS - Updated 06 November 2017 -- ADDITIONS: A few chosen compilations of other field-recordings of awesome VLF sounds from much higher geo-magnetic latitude locations (northern Alberta, Canada June 1996) have been added to this album here at Internet Archives. In you listen to the Alberta June 1996 recordings, you will likely notice that many of the quite bizzarre natural radio sounds are initiated by the pop and crash of lightning strokes. SpM

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.