HRN 193: Digital Voice is Exploding (maybe)

“This will be the year” for digital voice to explode in Ham Radio. That’s the prediction from David Rowe VK5DGR. David created CODEC2, the first open-source, really low bit-rate voice codec for amateur radio and more. He’s got several projects cooking to make digital voice work better and for more uses, on HF and VHF/UHF.

This program covers three related topics:

– The SM-1000 “speaker-mic” for FreeDV on HF.
– Improvements in CODEC2 and FreeDV aimed at making it work as well or better than SSB in weak-signal and noisy HF conditions
– A new VHF system using TDMA for one-frequency repeaters that won’t need in “input” frequency, and won’t need a duplexer.

David and Gary weave these topics into a conversation aimed at hams who don’t use DV now, but are curious about what it might bring in the future.


David’s Blog (details on FreeDV/CODEC2 development:

Interview with David on “Linux in the Ham Shack” (with 3% more badgers)…

David’s 2011 talk on CODEC2 at the ARRL/TAPR DCC:

The 2011 DCC’s banquet talk – “The Village Telco” – David’s project to provide extremely low cost telephone service in East Timore, Africa.


Author: CVRC

Crescenta Valley Radio Club is an organization over half a century old. Our members are amateur radio operators who share interests in radio and service to our community. Members help new members starting the hobby as well as helping other members with technical and operational problems of getting on the air. We keep ourselves up to date with the technological changes by inviting expert speakers to our meetings. CVRC closely supports GEARS (Glendale Emergency Auxiliary Radio). Many members are in both organizations and have provided communications for an emergency at Glendale Memorial Hospital, and with Cruise Night, the Montrose Christmas Parade, and various local themed running events. We meet once a month on the second Thursday of the month at USC Verdugo Hills Hospital at 7:00PM. Every Sunday we hold two nets. On our 445.680 repeater, we hold the No Chit Chat net at 7:50PM, and at 8:00PM, we switch to our 146.025 repeater for the Whats Going On Net. Both repeaters are located on top of Mount Thom and share use the city's antenna tower. Their power is backed up by both batteries and an emergency generator. We have several annual events. In June, we participate in the National Field Day by setting up several stations in Verdugo Park and operating completely "off the grid". Every August we have a barbecue in Crescenta Valley Park with a Fox Hunt activity where the members try to locate a hidden transmitter. When December comes around we come together for a traditional holiday dinner.

Share This Post On