Ham Voicing includes free and open-source software written by other people. Their copyright notices and licence terms are reproduced below.
Codec2 1.2.0 (github.com/drowe67/codec2) provides the low-bitrate digital voice codec used for M17. A 25-file subset of the voice sources is compiled into the app; FreeDV and the OFDM modems are not included.
Codec2 is free software. You may modify it, and reverse engineer your modifications for the purpose of debugging them, under the terms of the LGPL-2.1. The complete licence text ships inside the app and is available from the Codec2 project.
The source. The upstream release is at github.com/drowe67/codec2 (version 1.2.0). For at least three years from when you received the app we will also send you the exact Codec2 files it was built from, with our changes (a subset of the files and a generated version header), free of charge — ask at unixeer@gmail.com.
libgsm 1.0.22 (quut.com/gsm) provides the GSM 06.10 full-rate codec used for EchoLink audio. A 14-source subset is compiled into the app, built without WAV49 framing.
“Any use of this software is permitted provided that this notice is not removed and that neither the authors nor the Technische Universitaet Berlin are deemed to have made any representations as to the suitability of this software for any purpose nor are held responsible for any defects of this software. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.”
Copyright © 2010 the mbelib author; portions © the DroidStar project
Licensed under the ISC licence.
“Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies. THE SOFTWARE IS PROVIDED ‘AS IS’ AND ISC DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.”
These provide the AMBE-family voice codecs used by DMR, D-STAR, System Fusion, P25 and NXDN. The ISC licence permits modification, and four corrections were made and are marked in the source: a Hamming error-correction table shared between two decoders that turned one bit error into two; a mistyped quantiser step size; a missing factor from the published synthesis equation; and a D-STAR gain that was encoded one way and decoded another. The complete licence text and the list of changes ship inside the app.
Copyright © 2026 Yousuf AL Balushi (A41UX) / Unixeer
MIT licensed.
The speech analysis and parameter coding that drive the codecs above are an original implementation, written from TIA-102.BABA — the published Project 25 vocoder standard. No copyleft vocoder source was consulted in writing it. This is what allows the five AMBE networks to be included in the app at all.
Ham Voicing’s M17 implementation is original code written from the published M17 specification and verified against the M17 Project’s reference test vectors. No M17 Project source code is compiled into the app.
Copyright © Jonathan Naylor, G4KLX, and the MMDVMHost contributors. GNU General Public License, version 2 — not linked.
Ham Voicing’s DMR and P25 support was written with the MMDVMHost sources open, and they are the reference for how those protocols look on the wire: the burst layouts, the parity-check equations of the Golay, Quadratic Residue, Hamming and Reed–Solomon codes DMR uses for call setup, and the fixed record headers a P25 reflector expects. Those are interoperability facts fixed by ETSI TS 102 361 and by the P25 standard — an implementation reproduces them exactly or it does not work on the air. The error-correcting tables in the app are computed from their generator matrices rather than copied, and the test suite proves each code has the minimum distance its name claims. No MMDVMHost code is compiled into the app. MMDVMHost made amateur digital voice reachable for a great many operators, and this app would have been considerably harder to build without it.
ircDDBGateway copyright © Jonathan Naylor, G4KLX and contributors; xlxd copyright © the XLX developers. GNU General Public License, versions 2 and 3 — not linked.
Ham Voicing’s D-STAR support speaks DExtra to XRF and XLX reflectors. These projects are the reference for that wire format — the control and keepalive datagrams, the 56-byte header, the 27-byte voice frame, the checksum polynomial and its byte order, and the sync and scrambler constants — and for what a reflector actually checks before accepting a connection. A reflector accepts those exact bytes or drops the link, so there is nothing there to choose. The implementation is original code and no source from either project is compiled into the app.
Reflector data provided by DVRef, under the Creative Commons Attribution 4.0 International licence. The bundled snapshots that ship with the app were taken from the Pi-Star host files (© Andy Taylor, MW0MWZ), which are themselves built from DVRef; the XLX/URFD registry originates from xlxapi.rlx.lu.
The live refresh moved to DVRef on 14 September 2026, at the direct request of Andy Taylor MW0MWZ — “Please don't pull the files for your project from the PI-Star repo, the host files are now created by DV-Ref.” The app now reads DVRef's own directory API, and the attribution DVRef return with each response is stored with the data rather than restated by us.
The reflector, master and talkgroup lists Ham Voicing offers come from directories those projects publish for exactly this purpose. The app ships a dated copy so it works with no internet, and refreshes when it can — the picker shows the snapshot date it is carrying. The list of BrandMeister masters offered for DMR is the bundled copy alone: it comes from the Pi-Star host files and is not refreshed. No credentials are included: the password column the upstream files carry is deliberately dropped, so the list cannot be used to connect as anyone. Every reflector is run by volunteers, and keeping these lists current is work that somebody does for nothing.
The text of the app is set in Tajawal, an Arabic and Latin typeface by Boutros International. The Open Font License permits bundling it inside an app; the font file is included unmodified. The complete licence text ships inside the app, under About → Licences & Notices → Tajawal typeface, and is published at scripts.sil.org/OFL.
The app is built with Flutter and uses open-source Dart packages. The full list of those packages and their licences is shown inside the app under About → Licences & Notices → Flutter and Dart packages.
Data lookup powered by RadioID.net — © RadioID Inc. Used by written permission granted 8 September 2026. Not redistributed.
P25, DMR and NXDN put a numeric radio ID on the air and no callsign, so a station appears as 3183458. With “Show callsigns” enabled, Ham Voicing asks RadioID for the callsign belonging to an ID it has just heard and shows that instead.
RadioID approved this use in writing for low-volume, non-commercial, read-only lookups. Only the number heard on the air is sent — never your callsign, your logins, or your own radio ID — and only that number and the callsign returned are stored, on your device. No copy of the RadioID database is bundled with the app, and none is permitted to be: their approval excludes it. There is no search function; the app can only resolve an ID it has actually heard. The feature can be switched off in Settings and fails silently back to the number when offline.
Operators may supply their own RadioID API key in Settings. No key is built into the app.
EchoLink® is a registered trademark of Synergenics, LLC. The other network, protocol and project names mentioned in the app and on this site — among them AllStarLink, BrandMeister, D-STAR, DMR, M17, NXDN, P25 and System Fusion — belong to their respective owners, and are used only to say which networks the app can reach.
Ham Voicing is an independent client. It is not affiliated with, endorsed by or sponsored by any of those networks or their owners.
If you have a question about the licensing of any component, email unixeer@gmail.com.