As they say in the Classics "Sucks to be you" Brad VK2QQ
(Now running SSTV Mobile on 10.134, and Good Old Fashioned SSB Voice on 10.120, 10.125 and 10.1375) --- In digitalradio@yahoogroups.com, "kh6ty" <[EMAIL PROTECTED]> wrote: > > Rick, I prefaced my comment with " It is my belief that if "voice" of the > same bandwidth were allowed everwhere > "data" is allowed, the data segments of the bands would be overrun with > phone stations using DV." > > Perhaps it is not clear what I meant. For example, if someone comes up with > a DV of 300 hz bandwidth, it will quickly be widely used anywhere 300 hz > bandwidth signals are allowed, and the crush of phone users will leave > little space for modes like MFSK16 of the same bandwidth to operate, simply > because there will be so many people wanting to use phone instead of another > digital mode, like MFSK16, but that is just my personal belief. > > If there were a DV mode the same width as PSK31, then the same would prove > true, except that there are more spaces to use PSK31, because of its narrow > bandwidth, than there are digital operators looking for space (right now, > but changing). In fact there already is a sort of narrowband "DV" in my > DigiTalk program for the blind, which "speaks" the PSK31 text (at 50 wpm > text-to-speech), but, because going the other way (speech-to-text), still > has a 5% translation error rate at best, "speaking" must still be done by > typing, and that is a deterrent to many who might use PSK31 if they could > just speak into a mike and have errorless text go out over the air. > > As you point out, some sort of planned segregation is going to be inevitable > on shared bands. With phone and CW, there was a common language for > everyone, and sharing was possible by QRL or other Q signals on CW or the > equivalent on phone, but that sharing technique is useless when one mode > does not hear or understand another. We have yet to experience what it will > be like if everyone uses DV, there is not enough space to hold everyone, and > someone accidentally starts up on your frequency because propagation was > such he thought it was clear and did not happen to choose an alternate clear > frequency he could QSY to if he could just understand a request to do so. > > I believe the thing that makes it possible for PSK31 to have a space, for > example, is only that there is no true 31.25 Hz-wide phone mode. Of course, > the more narrow the mode, the more stations that will fit in any given slice > of spectrum, so it is advantageous to have the most narrow modes possible so > there is room for as many stations as possible. At some point, there will be > plenty of space, depending upon the demand, even if everyone used a voice > mode that is only 31.25 Hz wide. For example, if every RTTY contester only > used PSK63, there would probably be more than enough space so that during > contests, RTTY stations would not have to spread out so much. > > There was a psychological experiment some years ago in which scientists set > up two cages of rats, one overcrowded and one just at capacity. The rats in > the overcrowded cage ate each other until they were no longer overcrowded. > > Skip KH6TY > > > > > > > > > > > > It is almost for sure that if the FCC equated DV as being similar to any > > other digital mode, that DV would not take over the ever decreasing size > > of the text digital portions of the HF bands. There are several reasons: > > > > - the lower portions of the bands, historically used for the earliest > > text digital mode based on wetware decoding will likely see further > > reductions in that mode (CW), except during contest periods since almost > > no new hams are acquiring even basic CW skills, much less proficiency. > > This will allow for more space for text digital, assuming that text > > digital will be segregated in that manner. > > > > - since DV is likely to never be competitive with analog SSB for weak > > signals as analog due to the practical limitations of science. > > > > - if digital modes did increase in popularity, which would primarily be > > voice DV, there would be tremendous pressure to segregate digital and > > analog modes by a sizable majority of radio amateurs. And it works both > > ways, as you well noted, analog SSB is a serious hindrance to digital > > modes in general. > > > > - some phone bands are underutilized now, such as on 80 meters, with few > > stations on the lower end of the voice sub bands and yet CW and digital > > can be quite crowded in a space that is well under half of what we > > previously had. (And I admit was underutilized with that mix too). > > > > Unless we eventually go to bandwidth based bandplans, and at the same > > time do not segregate by mode (especially voice modes, whether analog or > > digital), then it would be entirely appropriate for hams to use narrow > > voice modes for spectrum conservation and do it in the appropriate > > bandwidth areas. Based upon comments made by Dave Sumner in the past, I > > am not sure that will be supported by ARRL, since he seems to suggest > > that even if we have bandwidth limits, we will not necessarily mix > > modes. In fact, it was at that point that I was no longer as supportive > > of the withdrawn ARRL proposals, because it will still not allow us the > > ability to use voice and data intermixed on the HF bands (even if only > > in small areas) which I consider to be one of the most unfortunate > > effects of our current rules. > > > > The best band plans are those that allow for the best use of a shared > > resource. If one part of the band is congested and another part is under > > utilized, that means the planning is flawed. And since conditions and > > events constantly vary, the best regulations are the minimum necessary > > to make more efficient use of the bands for the maximum number of shared > > resource users. > > > > 73, > > > > Rick, KV9U > > > > > > > > kh6ty wrote: > >> It is my belief that if "voice" of the same bandwidth were allowed > >> everwhere > >> "data" is allowed, the data segments of the bands would be overrun with > >> phone stations using DV. Phone is the easiest to operate and obviously > >> the > >> preferred mode. During the "bandwidth petition" discussions, it became > >> clear > >> that the phone people wanted to take over as much space as they could, > >> which > >> is understandable, since the phone bands are always overcrowded. > >> > >> I don't pretend to know the real reasoning behind the FCC determination > >> that > >> DV is phone (just like analog voice), but practically, it currently > >> serves > >> to protect digital mode operators from being overrun by a multitude of > >> phone > >> operators. In light of the fact that you can sometimes copy an analog > >> phone > >> signal through another analog phone signal, but cannot do that with DV, I > >> think we are fortunate that the FCC has taken the position they have. > >> > >> Skip KH6TY > >> > >> > > > > > > > -------------------------------------------------------------------------------- > > > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.5.516 / Virus Database: 269.17.6/1192 - Release Date: 12/21/2007 > 1:17 PM >
