{"id":162,"date":"2018-12-30T17:10:40","date_gmt":"2018-12-30T17:10:40","guid":{"rendered":"http:\/\/localhost:8080\/wordpress\/?page_id=162"},"modified":"2022-01-23T20:35:48","modified_gmt":"2022-01-23T20:35:48","slug":"earthaudio-vlf-receiver","status":"publish","type":"page","link":"https:\/\/aprovechar.org\/?page_id=162","title":{"rendered":"EarthAudio VLF Receiver"},"content":{"rendered":"\n<p><strong>Summary:<\/strong>  ... to be written ...<\/p>\n\n\n\n<p><strong><a href=\"http:\/\/aprovecho.airpost.net\/aprovecharLab\/VLF\/VLF_summary_v2.pdf\">Link to a Technical Brief<\/a><\/strong><\/p>\n\n\n\n<div style=\"height:20px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<figure class=\"wp-block-gallery columns-3 is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\"><ul class=\"blocks-gallery-grid\"><li class=\"blocks-gallery-item\"><figure><img loading=\"lazy\" decoding=\"async\" width=\"850\" height=\"660\" src=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype2.jpg\" alt=\"VLF closed\" data-id=\"255\" data-link=\"https:\/\/aprovechar.org\/?attachment_id=255\" class=\"wp-image-255\" srcset=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype2.jpg 850w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype2-300x233.jpg 300w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype2-768x596.jpg 768w\" sizes=\"auto, (max-width: 850px) 100vw, 850px\" \/><figcaption class=\"blocks-gallery-item__caption\">VLF Receiver Closed<\/figcaption><\/figure><\/li><li class=\"blocks-gallery-item\"><figure><img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"1024\" src=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype3-768x1024.jpg\" alt=\"VLF open\" data-id=\"258\" data-link=\"https:\/\/aprovechar.org\/?attachment_id=258\" class=\"wp-image-258\" srcset=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype3-768x1024.jpg 768w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype3-225x300.jpg 225w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/VLFReceiverPrototype3.jpg 960w\" sizes=\"auto, (max-width: 768px) 100vw, 768px\" \/><figcaption class=\"blocks-gallery-item__caption\">VLF Receiver Open<\/figcaption><\/figure><\/li><li class=\"blocks-gallery-item\"><figure><img loading=\"lazy\" decoding=\"async\" width=\"576\" height=\"1024\" src=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/Field_Test_St_Lucia-576x1024.jpg\" alt=\"Field test in St. Lucia\" data-id=\"253\" data-link=\"https:\/\/aprovechar.org\/?attachment_id=253\" class=\"wp-image-253\" srcset=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/Field_Test_St_Lucia-576x1024.jpg 576w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/Field_Test_St_Lucia-169x300.jpg 169w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/Field_Test_St_Lucia.jpg 720w\" sizes=\"auto, (max-width: 576px) 100vw, 576px\" \/><figcaption class=\"blocks-gallery-item__caption\">Field Test in St. Lucia<\/figcaption><\/figure><\/li><\/ul><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/3ChannelSpectrogram_pick_up_box_rotate_put_back_down-1024x576.png\" alt=\"Spectrograms of all 3 channels\" class=\"wp-image-252\" srcset=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/3ChannelSpectrogram_pick_up_box_rotate_put_back_down-1024x576.png 1024w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/3ChannelSpectrogram_pick_up_box_rotate_put_back_down-300x169.png 300w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/3ChannelSpectrogram_pick_up_box_rotate_put_back_down-768x432.png 768w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/3ChannelSpectrogram_pick_up_box_rotate_put_back_down.png 1920w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption>Spectrograms of all 3 axes as the instrument is picked up, rotated, and put back down. The experiment was performed indoors in Montpelier, Vermont, yet the 24 kHz <a href=\"https:\/\/en.wikipedia.org\/wiki\/VLF_Transmitter_Cutler\">Cutler, Maine VLF<\/a> signal is clear. <strong><a href=\"http:\/\/aprovecho.airpost.net\/aprovecharLab\/VLF\/3ChannelSpectrogram_pick_up_box_rotate_put_back_down.png\">(link to image)<\/a><\/strong><\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/SpectrumOfTimeSegment-1024x576.png\" alt=\"Spectrum of time segment\" class=\"wp-image-254\" srcset=\"https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/SpectrumOfTimeSegment-1024x576.png 1024w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/SpectrumOfTimeSegment-300x169.png 300w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/SpectrumOfTimeSegment-768x432.png 768w, https:\/\/aprovechar.org\/wp-content\/uploads\/2019\/01\/SpectrumOfTimeSegment.png 1920w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption>Power spectrum and spectrogram of a short time segment, showing the VLF signals rising well above the broadband background noise. The experiment was performed indoors in Montpelier, Vermont, yet the 24 kHz <a href=\"https:\/\/en.wikipedia.org\/wiki\/VLF_Transmitter_Cutler\">Cutler, Maine VLF<\/a> signal is clear. <strong><a href=\"http:\/\/aprovecho.airpost.net\/aprovecharLab\/VLF\/SpectrumOfTimeSegment.png\">(link to image)<\/a><\/strong><\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Summary: &#8230; to be written &#8230; Link to a Technical Brief<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-162","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/aprovechar.org\/index.php?rest_route=\/wp\/v2\/pages\/162","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aprovechar.org\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/aprovechar.org\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/aprovechar.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aprovechar.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=162"}],"version-history":[{"count":9,"href":"https:\/\/aprovechar.org\/index.php?rest_route=\/wp\/v2\/pages\/162\/revisions"}],"predecessor-version":[{"id":449,"href":"https:\/\/aprovechar.org\/index.php?rest_route=\/wp\/v2\/pages\/162\/revisions\/449"}],"wp:attachment":[{"href":"https:\/\/aprovechar.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=162"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}