Julian, thanks for your comments. Yes, laws are laws. Also the Hammurabi rule "If a man puts out the eye of an equal, his eye shall be put out" was a law but I don't think that it would be of great help in our modern society.
I agree with you that simulations should be performed prior to any other "on air" experiment. I think that this is already a common practice nowadays or at least that nobody interested in a serious development would omit to perform it today. I also agree that amateur bands are not just an experimenter's playground but this implicitly means that they are not exclusive to "communicators". If I were an experimenter I would like to see acknowledged my right to make my experiments somewhere in our bands. I would have no interest interfering other users activity, I would just need a portion of the spectrum where me or other amateurs on the other side of the Atlantic Ocean were not considered criminals just because we are validating a model on the field. I don't agree that we should use modes which have already been invented and stop looking for new ones. Research and development in communications and in information theory are everything but dead. Turbo codes were submitted to the attention of the research community just fiftheen years ago, when many had already missed the hope that the Shannon channel capacity could be really approached. Should Berrou, Glavieux and Thitimajshima have made more use of what had been already invented instead of experimenting what had not be done yet? And what about those who dedicated their time inventing new efficient algorithms to decode LDPC (or Gallager's) codes, as David MacKay did few years later? Koetter (unfortunately passed away at a still young age), one of the two researchers who found an algebraic soft decision method to decode better than before the Reed-Solomon codes, as those used in Joe's JT65, published his work in 2003 or so. Should we have stopped our alternatives to knowledge and technologies available in 2002? I don't think so. We should better keep up with news and new modes. Nico, IV3NWV --- In digitalradio@yahoogroups.com, "g4ilo" <jul...@...> wrote: > > Laws are laws, whether you like them or not. And, in this particular context, > is it actually necessary to go on the air to carry out experiments of this > type? As has been mentioned in several posts. there are ionospheric > simulators that permit the testing of different modes. > > The amateur bands are not just an experimenter's playground. They are also > used for communication. And communication becomes increasingly difficult when > you have a Tower of Babel of different, mutually incompatible modes competing > for the same frequencies. > > There are dozens of data modes that have been developed in the last few years > and most now simply lie unused because not enough people were interested in > using them to make it possible to have everyday contacts. Would it not be > better to make more use of the modes we already have than keep on inventing > new ones? > > I think that before any mode is allowed off the simulator and into general > use it should be proven to have benefits not provided by any pre-existing > modes, as well as to justify its use of bandwidth. I think there is an > argument for setting aside a small section of space for on-air > experimentation with unapproved modes. But the situation where existing users > of the bands suddenly have their activities disrupted when people start going > mad with some flavour of the month new mode is unacceptable, and the controls > the FCC exercise over amateurs in the USA do at least go some way to prevent > this. > > Julian, G4ILO
