February 06, 2014

FreeDV: A new way to talk on HF

KN5G in QSO with WB9TLH with FreeDV.
by KN5G - This is a screen shot of the FreeDV, or digital voice software application. This software basically lets you hook up an microphone to your computer, the computer and software compresses and digitizes your spoken words and then sends the digital information to your radio transceiver where the data is transmitted over the air to another amateur radio operator running the same software. Once the data is received it is decoded by the FreeDV software and played back by the computer on the receiving end. This is all done in real time by the way.

So what's the point you might ask?
The biggest advantage is that the audio information can be compressed in the computer and when it is transmitted over the air it only takes a small portion of the bandwidth that a common Single Side Band signal occupies. Another advantage is that the information can be transmitted from point A to point B with a fraction of the power needed to complete the same exchange of information when using the Single Side Band mode. So, rather than needing a kilowatt of power to work DX around the world using SSB, you could do the same with a 100 watt HF radio and the digital voice mode. 

I think we will see a lot more of this digital voice in the future as more amateurs adopt the mode and the software is revised and updated with more options.  Check out the "FreeDV" website here.