g4ilo wrote: > I don't know if that is a dig at one of the arguments I have made in the past,
Certainly not directed at you as an individual. I just feel that things like sustained throughput which includes the effect of FEC & processor gain in the case of SS need to be included. So it's not as simple as 2.2khz bandwidth divided by 128 bps as a figure of merit. Skip's testing did show that for it's 2.2khz bandwidth, ROS was not the leader in throughput. What will never be known is if multiple ROS signals could have shared that bandwidth without interference, or if it could have lived in large signal (SSB, FM, etc) areas without interference. > but I do believe that 2.25kHz ROS was too wide for our existing HF bands. > Regardless of the merits or otherwise of a mode, people can't go on inventing > new modes unless they can also come up with a place for them to be used that > doesn't squeeze out existing users. Here we disagree somewhat. I would mostly agree for areas like 40m, especially if multiple channels were used like ROS did. But I don't agree that a new & otherwise legal mode that is SSB width should be excluded just because the bands can be crowded. If we followed your recommendations, SSB, SSTV, PSK, all the digital modes, etc would never have been allowed to be used. This is not to be construed that the approach the ROS implementor took was a model of how things should proceed! > the chances of finding 2.25kHz of 20m unoccupied are pretty slim at any time. > If the mode is otherwise legal, it's up to the operator to find a hole to operate. That's not a matter for legislation. :-) Personally, I think we missed a chance to see what could be done with an AFSK based SS approach in the wider & less used bands. Test in the strong signal areas, where interference to legacy modes would be minimal. Maybe DSSS between the FM frequencies on 10m where there would not be interference to each other. Use a wider spreading sequence to increase processor gain (and improve noise performance). Add in a CDMA approach to allow multiple users in the same slots. There are many possibilities which could be explored. If your point is that 3 SSB width slots in the crowded 40m data section was not appropriate, I agree! Other bands? Not so sure. :-) Have fun, Alan km4ba
