FreeDV Digital Modes

Whats new in Digital voice over HF radio?

Download FreeDV Digital Voice for HF


FreeDV is a GUI application for Windows and Linux that allows any SSB radio to be used for low bit rate digital voice.

Speech is compressed down to 1400 bit/s then modulated onto a 1100 Hz wide QPSK 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.

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 FDMDV modem and Codec 2 Speech codec used in FreeDV are also open source.

A good place to try the FreeDV digital voice software is on 14.236. Enjoy

New Upgrade as of version 0.96.6
May 2014: More repairs to T/R control.

The new version 0.96 provides a 1600 bit-per-second mode that communicates at much lower signal levels than previously. Communications should be readable down to 2 dB S/N, and long-distance contacts are reported using 1-2 watts power. A compatibility mode for communication with the older 0.91 version is included. An executable program for Windows is presently available, Linux and other platforms are coming soon.

Here is a good video showing FreeDV in use on the 20mtr band.

Old now but it was the start of digital voice over HF. DRMDV 2.0 DRMDV is the next generation of digital voice over HF SSB. DRMDV offers increased robustness and interference rejection with improvements over the WinDRM implementation.

Digital Voice Mode
FDMDV is the latest digital voice mode on HF – it caters to high quality digital voice under poor band conditions, in only 1100Hz bandwidth!.
More information about the mode will be posted soon – please check back often for new updates!
Download here
Read the FDMDV Usage Documentation v1.4b in PDF format to learn how to use, configure and optimize your FDMDV “in above download”
Join the new digitalvoice FDMDV Mailing List to chat with others and exchange ideas about using digitalvoice and FDMDV
Breaking News!
Weekend AOR Digital Voice Net will is QRV every Saturday / Sunday – Summer 2:00PM EDT, 1800 UTC, Winter 2:00PM EST, 1900 UTC – 14.236 QRG USB. WinDRM / FDMDV Digital Voice Net follows at 3:00PM EDT, 1900 UTC , Winter 3:00PM EST 2000 UTC – 14.236 QRG USB