FreeDV - Free Digital Voice

FreeDV - Free Digital Voice

Digital Audio over HF SSB

FreeDV Resource Page


FreeDV is a GUI application for Windows, Linux and MacOS (BSD and Android in development) that allows any SSB radio to be used for low bit rate digital voice.

Speech is compressed down to 1600 bits/s then modulated onto a 1.25 kHz wide 16QPSK signal which is sent to the Mic input of a SSB radio. On receive, the signal is received by the SSB radio, then demodulated and decoded by FreeDV. Communications should be readable down to 2 dB S/N, and long-distance contacts are reported using 1-2 watts power.

FreeDV was built by an international team of Radio Amateurs working together on coding, design, user interface and testing. FreeDV is open source software, released under the GNU Public License version 2.1. The FreeDV modem and Codec 2 Speech codec used in FreeDV are also open source.

Links and Download - Main site

Latest Windows version
Macintosh OS X
Debian package repository, Wheezy x86 and amd64

Red Hat Enterprise Linux repository set-up RPM
Red Hat Enterprise Linux 6 repositories, i686 and x86_64
Fedora repository set-up RPM
Fedora repositories, Fedora 17, 18, 19, i686 and x86_64
Android source code

Groups and Help

Use the FreeDV Online Finder to rendezvous with other users, see what frequencies they are using and coordinate skeds (Broken - fixing it)

Join the new digitalvoice Mailing List to chat with others and exchange ideas about using digitalvoice and FreeDV!

Breaking News!

About the Mailing List

This mailing list is provided to discuss all topics related to digital voice transmissions over the Amateur Radio HF spectrum.

Google Groups Subscribe to digitalvoice / FreeDV
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FreeDV - Free Digital Voice
Updated: 12-Jun-13 -