For those of you interested in the Next Generation Beacons project a new software package for the DDS unit has just been released (1.2.0). New features are WSPR-15 among others: http://www.rudius.net/oz2m/ngnb
The Next Generation Beacons platform is open to others and the software can easily be adapted to other modulations and sequences. Furthermore, is the new platform frequency and time locked to GPS. Thus the frequency accuracy is better than 5 mHz.