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Docs Morse & Communication SDR Decoding Morse

SDR Decoding Morse

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Decoding the beacon's Morse automatically from an SDR recording: the software options and the settings that make decoding reliable.

SDR Decoding Morse

The beacon transmits Morse so any receiver can decode it, and software decoders make the receiving side effortless. This page is the software path.

The pipeline

SDR -> audio (FM demodulated) -> decoder -> text

The decoder needs clean audio: the beacon’s tone must be the dominant sound in the passband, with the correct speed setting.

The decoder options

ToolPlatformNotes
CW decoders in SDR appsThe SDR software itselfBuilt-in, good for live
Standalone CW decodersDesktop / mobileAccept audio files or live input
Web-based decodersBrowserPaste a recording

The Morse Decoder Tools page has the full list with setup notes.

The settings that matter

SettingValue
Speed (WPM)Match the beacon’s setting (default 12)
Filter bandwidthNarrow around the tone: 200 - 500 Hz
Tone frequency700 Hz (see Audio Tone Details)
Noise gateOn: keeps hash from becoming characters

The failure modes

SymptomCause
Garbage charactersSpeed or filter mismatch
Missing charactersSignal too weak, or the noise gate too aggressive
Everything decodes wrongThe recording is distorted (see Audio Recording Guide)

The verification

A decoder that reads the test recording correctly (see Audio Recording Guide) will read the live signal: the same audio path, the same settings. Verify once, then trust the setup.