{
  "patent_number": "US 1342885",
  "country": "US",
  "title": "How Edwin Armstrong Invented the Superheterodyne Radio Receiver",
  "original_title": "Method of receiving high-frequency oscillations",
  "summary": "A foundational 1920 patent by Edwin Armstrong that describes the superheterodyne circuit, the technology that allowed radios to tune into specific stations clearly and reliably.",
  "what_it_does": "The patent describes a method for receiving high-frequency radio signals by converting them into a lower, intermediate frequency before processing. By mixing the incoming signal with a locally generated oscillation, the device creates a beat frequency that is easier to amplify and filter. This process allows a radio to isolate a single broadcast station from the crowded airwaves without losing signal quality. It essentially acts as a high-precision filter for invisible radio waves.",
  "what_it_does_not_cover": [
    "Does not cover the basic concept of radio transmission itself.",
    "Does not cover digital signal processing or software-defined radio techniques.",
    "Does not cover the vacuum tube hardware components themselves, only the circuit arrangement."
  ],
  "filed": "1919-02-08",
  "granted": "1920-06-08",
  "expires": "1939-02-08",
  "status": "expired",
  "holder": "Individual",
  "holder_url": "https://patentbrief.org/company/individual",
  "inventors": [
    {
      "name": "Edwin H Armstrong",
      "url": "https://patentbrief.org/inventor/edwin-h-armstrong"
    }
  ],
  "times_cited": 31,
  "tags": [
    "telecommunications",
    "consumer_electronics"
  ],
  "abstract": null,
  "url": "https://patentbrief.org/patent/us/1342885/superheterodyne-radio-armstrong",
  "markdown_url": "https://patentbrief.org/patent/us/1342885/superheterodyne-radio-armstrong/md",
  "google_patents_url": "https://patents.google.com/patent/US1342885",
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}