Oh, that’s a shame - to close because of the skip dstance.
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The FCC classifies both SSB and digital voice as voice modes and we put them in the voice subband. Data-oriented digital modes go with CW and RTTY. So for us, a separate mode key makes sense.
Digital voice should have a solid SNR advantage over SSB. As far as I can tell, D-Star and DMR do not have an advantage. They were designed for features, not weak signal performance. They support things useless for amateurs, like encryption.
VK5DGR (David Rowe) is doing some great work in weak signal digital voice. Right now, it sounds differently weird than SSB, but already works at worse SNR than SSB. This is an area where amateurs really are advancing the state of the art. Commercial digital voice hasn’t improved much since the voice comms for Skylab.
wunder
Most of the commercial digital handset system all use the DSI Codec that first came to most amateur attention in D-Star. It’s the same codec for DMR and System Fusion and P25 (I think).
It’s old but is available as a ready to use solution in hardware or for implanting as IP in your own SoC. Still sounds rubbish. 
I think DMR uses the proprietary AMBE codec in a 2400 bps channel. There are two channels.
David Rowe is working on open source codecs for 1300 and 700 bps. That’s like doing voice comms over a 1200 baud Hayes modem.
wunder
Yes AMBE at 2k4 with 1k2 FEC ISTR.
Hi Andy,
Re code name for these modes why not DA for digital audio. (Initially I thought of reversing the letters DV for ie Voice, Digital, but that might scare people off)
One of the inhibitors to people taking up any digital voice mode is the lack of a common system across makers.
Could the big makers make a multimode box with FM, D-star, Fusion, P25 and Motorola’s DV all in the one box?
One of the factors that boosted FM activity in VK was the recycling into the amateur community of FM radios from Taxi fleets and Country Fire Brigades as they upgraded. Maybe in a decade or so we will see the current crop of commercial digital radios entering the amateur market for a low price.
73
Ron
Hi Ron,
DV is the abreviatiion used elsewhere for Digital Voice, so I don’t think changing it here to DA is a good idea.
Ed.
Hi Ed,
Just trying to avoid brand issues.
You must be a senior manager. When I had a life they used to say to me “I don’t think changing …is a good idea” at least once a month.
73
Ron
VK3AFW
DV is the term used by amateurs that encompasses voice modes using digital encoded audio. But it’s much,much more than just digital audio. Whilst unwieldy,it would be perfectly possible to send and receive digital audio using CW or semaphore or Aldis lamps… that is not DV!
Err? DV is a brand ??? which one please?
73 Ed.
Hi Andrew
The number of contacts made is certainly impressive and gratifying.
I suspect you are reflecting on the relative ease of making a qualifying number of contacts using the DMR box, compared with the frequently more difficult task of making the 4 contacts using the fm or SSB modes. I guess while the DMR devices are still novelties in VK1 there is a bigger potential audience for them.
Hope DMR interest remains strong among the locals and continues to provide the contacts.
Andrew VK1DA/VK2UH