Sunday, June 03, 2018

FreeDV digital voice story on WIA broadcast via FreeDV

The recursion appeals to me, here is a story about the new FreeDV 700D mode complete with comparison with SSB. I heard the story via the relay over FreeDV 1600 from Adelaide.


Interestingly I find digital voice decoded is more intelligible in a small external speaker than in headphones.

After the broadcast relay, Mark, VK5QI conducted a callback on 700D with stations VK3PR, VK3RV, VK5DGR and VK5APR. We often got perfect signals despite some interesting selective fading such as this on VK3RV.


The broadcast on FreeDV is at 10am Sunday Adelaide time on 7.177MHz.

700D uses much less bandwidth than sideband, here's a waterfall comparison David VK5DGR sent me this morning.


One thing to note (it confused me) is that FreeDV uses the same sideband as normal voice on each band. This is unlike other digital modes which generally use upper sideband everywhere.

Installing FreeDV 1.3 on Ubuntu or Debian

Not everyone likes to build from source. You can download and install FreeDV 1.3 (which you need for the new 700D mode) as follows:


Download these files:

http://launchpadlibrarian.net/372108070/libcodec2-0.8_0.8-2_amd64.deb
http://launchpadlibrarian.net/372171996/freedv_1.3-1_amd64.deb

In a terminal go to the Downloads folder and:

sudo dpkg --install libcodec2-0.8_0.8-2_amd64.deb
sudo dpkg --install freedv_1.3-1_amd64.deb


No comments: