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Surfin’: Developing New Digital Voice Software, Continued

12/02/2011

By Stan Horzepa, WA1LOU
Contributing Editor

This week, we check back in and discover VK5DGR’s amazing progress in the digital voice software field.

The September 10, 2010 installment of Surfin’ considered at the results of one year of digital voice codec smithing by David Rowe, VK5DGR.

Fifteen months later, David has announced: “I'm in the process of releasing a 1400 bit/s version of Codec 2. Through efficient quantization of the Line Spectrum Pairs (LSPs), I have reduced the bit rate from 2500 to 1400 bit/s with only a small change in quality. This bit rate makes the codec very useful for digital voice over HF radio channels.”

David adds that building a 1400 bit/s communications quality speech codec is a highlight of his career. That is saying a lot considering VK5DGR's amazing ride thus far.

You can check out David’s progress by visiting his blog and website and/or by joining the Freetel-codec2 mailgroup where David announces most of his happenings.

Thank you Anthony Cutler, KE7HQY, for the heads-up concerning VK5DGR’s achievement.

Until next time, keep on surfin’!

Editor’s note: Stan Horzepa, WA1LOU, likes the unusual in radio. To contact Stan, send e-mail or add comments to the WA1LOU blog.



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