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dumphfdl

HFDL decoder for long-range oceanic aircraft datalink

What it does

Decodes HFDL, the HF datalink aircraft use where there is no VHF ground station — over oceans, poles and deserts. It demodulates the shortwave carriers, tracks the ground-station network, and with libacars decodes the application layer, including position reports from aircraft several thousand kilometres away.

Why you would want it

It is the one aeronautical mode that does not need line of sight, so it is the only way to hear datalink traffic from mid-ocean with a receiver at home. It also rewards an HF antenna you may already have for amateur bands, and it decodes several ground stations at once from a single wideband capture if your SDR has the bandwidth.

Before it will work

An HF-capable SDR — an RTL dongle alone will not do, since HFDL lives between roughly 2 and 22 MHz. Airspy HF+, an upconverted RTL, or anything SoapySDR reaches with HF coverage. libacars must be installed first, which the catalog sequences.

How it installs

  • source (cmake) from https://github.com/szpajder/dumphfdl/archive/refs/tags/v1.7.0.tar.gz
  • build dependencies: patch, build-essential, cmake, pkg-config, libglib2.0-dev, libconfig++-dev, libliquid-dev, libfftw3-dev, libsoapysdr-dev, libsqlite3-dev
  • SCOPE.md listed dumphfdl as DragonOS Tier 1 — "apt-installable or an upstream .deb". It is neither: absent from Debian stable and unstable and from every target's apt, measured in containers. It is a source build, and that correction is recorded in dragonos-tier1-inventory.md.

Binaries this produces:

  • src/dumphfdl

Known problems

liquid-dsp is a hard requirement and the version matters — upstream needs 1.3.0 or newer. Skywave ships dumphfdl in its ISO but its published installer scripts do not build it at all, which is one of the clearest signs that those scripts and that image have diverged.

Keeping it current

  • probe: github tags
  • strategy: rebuild
  • Tagged releases, infrequent. Last commit on the default branch 2025-11-02 (verified 2026-08-28 from the branch head — D-032).

Where to get help with the software itself

GitHub issues at https://github.com/szpajder/dumphfdl/issues.

Source: catalog/packages/dumphfdl.yaml