When you say ICOM digital voice modes, are you referring to the D-Star system developed by JARA? This is a "sort of" open system, although it is not quite as open as some of us initially thought. The vocoder uses the proprietary AMBE product so that does complicate things. Also it does not seem to have the most open documentation.
Some hams have started some preliminary work on a more open standard but not much has come of it as yet that you can see on the web. There is a beginning opendstar.org that has a few files posted. D-Star is only possible on the VHF and higher bands since it is much too wide for HF use. Even then, it suffers from low quality audio compared to current analog technology when signals are good. The main attribute is that you can trade off audio quality for narrower bandwidth. The current AOR approach to DV is proprietary and I don't see how it can succeed as anything other than a minor niche product. It is very costly at about the price of a low end HF rig and is not compatible with the freely available DV computer sound card modes which work about as well. Its main attribute is that you can use it for mobile use without a computer. The problem with any HF DV is that it really is not very practical as it requires very good signals to work adequately and amateur radio often is challenged with weak signals. 73, Rick, KV9U Jack Hamilton wrote: > > Is this the reason why the AOR and ICOM digital voice modes are not > available in sound card programs? Is the problem in the sound chip, the > main CPU, or somewhere else (the serial interface, for example)? > > > >
