ELF

{
  "id": "MLC-T-IND-002018",
  "term": "ELF",
  "field": "Industrial and trades",
  "definition": "An abbreviation for Extremely Low Frequency, the band of radio frequencies from 3 to 30 hertz as designated by the International Telecommunication Union. These frequencies have very long wavelengths, from 10,000 to 100,000 kilometers, allowing them to penetrate conductive materials like seawater and earth. ELF is used for communicating with submarines and in geophysical surveys to study deep structures within the Earth's crust.",
  "subject": "Industrial electronics",
  "see_also": [
    "RF"
  ],
  "translations": {
    "de": "ELF",
    "es": "ELF",
    "fr": "ELF"
  },
  "url": "https://mlchart.com/terminology/industrial/elf/"
}