Amateur Digital Voice

Amateur Digital Voice has been with us for several years now. Former Chelmsford Amateur Radio Society member Charles Brian G4GUO (he moved to West Sussex a few
years ago) did the pioneering work on this back in the late 90's.

The recent dramatic increase in Digital Voice on the HF bands has been due to availability of free software which means anyone with a PC and a HF SSB transceiver can run
this exciting new mode.

The great advantages of Digital Voice are the better audio quality, similar to FM, and freedom from the pops and crackles that mar HF voice signals. In addition, because Digital Voice is a constant amplitude mode it doesn't suffer
from the audio breakthrough problems with Hi-Fi's and other electronic evices that you can get with high power SSB.

The system that most Amateurs are now using is derived from the DRM standard which was developed for digital Medium Wave and Short Wave broadcast stations.
The transmited signal occupies a bandwidth of just 2.3 kHz so can be used with any HF SSB transceiver using just a standard PSK31 or SSTV sound card to rig interface.

The software for this mode can be downloaded from:
http://www.qsl.net/hb9tlk/hamdream/

Trevor M5AKA

Other recent stories..