David Rowe, VK5DGR, has been a guest target since QSO Today episode 16 with Bruce Perens, K6BP because of David's seminal work with audio codecs for digital audio on HF. David has a strong background in digital voice, a technology that is now the foundation for all of the telephony and voice over IP that we do. As an advocate of open source and the consummate teacher, David shares all of his work while educating us with his blog, rowetel.com. VK5DGR is Eric, 4Z1UG's QSO Today.