[hfsig] Re: [Flexradio] The final nail in the coffin of Morse ?
Robert McGwier rwmcgwier at comcast.netSat Jul 23 07:03:22 UTC 2005
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Right. I believe you. I am indeed hoping for a lot more than we can do now "officially" Bob N4HY Walt DuBose wrote: > Bob, > > I have to agree with Jeff. I don't think the Board's intent was for > anything but legacy AM voice having 9 KHz bandwidth...certainly not > data...especially not data. > > I believe that when the actual proposal is published, it will > specifically allow only legacy AM voice to have 9 KHz bandwidth and > all other modes must be not more than 3.5 KHz wide. > > The problem is "...Since OFDM - fade designed trellis QAM seems like > AM to me anyway." If the Board doesn't see it that way and sees that > 9 KHz bandwidth only applies to a legacy AM voice transmission, then > you are stuck with 3.5 KHz bandwidth. > > I hate like heck to throw cold water on you notion; but, I'm afraid > that the Board didn't intend for the a 9 KHz bandwidth signal to be > anything but legacy AM voice and their proposal will have the > exemption specifically for legacy AM voice and thus all other modes > are stuck to 3.5 KHz bandwidth. > > Specifically, the ARRL prosal will follow this thought process... > > "The regulation-by-bandwidth issue dominated the Board's second > meeting > of the year in Windsor, Connecticut. After a great deal of give > and take > among its members, the Board ultimately okayed raising the maximum > bandwidth the EC had proposed for frequencies below 29 MHz from > 3.0 kHz > to 3.5 kHz. A provision permitting the continued use of > double-sideband > AM with bandwidth of up to 9 kHz was retained." > > "Significantly, the Board also agreed that maximum permitted > bandwidth > should be defined in terms of necessary rather than occupied > bandwidth. > In addition, the modified proposal removes the exception for > independent > sideband (ISB) emissions--apparently not used in the Amateur > Service-- > and drops certain mode restrictions on Novice and Technician class > operators." > > "The ARRL proposal would leave two important FCC rules unchanged. > §97.307(a) says: "No amateur station transmission shall occupy more > bandwidth than necessary for the information rate and emission type > being transmitted, in accordance with good amateur practice." > §97.101(a) > reads: "In all respects not specifically covered by FCC Rules each > amateur station must be operated in accordance with good > engineering and > good amateur practice." > > So what then? On the one hand the Board says the bandwidth will be no > more than 3.5 KHz except AM which can be 9 KHz wide and then says that > no transmission shall occupy mode bandwidth than necessary for the > information rate and emmision type being transmitted. > > So is OFDM a transmission type? What does "No amateur station > transmission shall occupy more bandwidth than necessary for the > information rate and emission type being transmitted" really mean? Ok > so perhaps this is the outlet. > > So if my OFDM data transmission required 15 KHz to transmit 50 Kbps, > is that OK? > > IMHO the only thing to do is to start now and write our own proposal > to the FCC in a technical yet easily to understand format. A real > challange...technical yet easily to understand. > > We are going to have to "one up" the ARRL so than any proposal they > present will seem like (because it will be) a proposal that doesn't > advance technology and the state of the communications art, rather one > (ours) that promotes experimentation in the advancement of the > communications art. > > The case must be clearly made that in data communications that > increased throughput and robustness will require bandwidth wider than > 3.5 KHz and it will be necessary to define high-speed and robustness > as well as show, through the use of live (on-the-air) demonstrations > or computer modeling/channel simulation the superiouity of any new > mode or types of modes. > > My greatest fear in all this is that it will NOT foster further > development or the need for SDRs. If this is true (with the passage > of this sort of restrictive bandwidth as the League is proposing), > then we can show that the League's proposal is NOT advancing the state > of the art, rather preventing experimentation and advancement of the > state of the communications art. > > On 23 Jul 2005 at 12:46 AMBob wrote: > >I don't think 9 Khz would be widely tolerated without a specific say > so. I am >not talking about theoretical legal limits. I could put a > 200 Khz wide signal >on 20 meters in a few seconds by reaching over > and turning on my FSK >transmitter on my Gnu Radio USRP and it is > likely no one would even know I was >there. I am talking about > "officially sanctioned" or blessed operations of the >type (say) Walt > could take and put into ARES, RACES, FEMA, etc. sites. > > And yes, the proposal needs to be a recognized mode that we can > present to and to be used by ARES, Red Cross, FEMA, etc. > > I believe that this will take the concerted effort on many individuals > part to > make a bandwidth proposal to the FCC. > > 73, > > Walt/K5YFW > > > Jeff King wrote: > >> There is effectively no bandwidth limit for OFDM modulations on HF as >> we speak, > > > other then they be documented so not clear to me how the ARRL > proposal will > > cause anyones dreams to come to fruition. > >> >> On Sat, 23 Jul 2005 02:28:49 +0000, Robert McGwier wrote: >> >>> You know my feelings already. These suggestions will enable real HF >>> modems for the first time. I would not have dreamed of building a >>> reasonable HF modem until the League proposals were brought >>> forward. It would have just been a waste of time. I would have >>> been run out of amateur radio for even suggesting doing MS188- >>> 110A,B, etc. on (say) 20 meters in the phone band. Now I can see >>> doing some serious work and it actually could be interesting at >>> last. We could have 19-50 Kbps NVIS modems kicking some real butt >>> in 9 Khz bandwidth. Since OFDM - fSince OFDM - fade designed >>> trellis QAM seems >>> like AM to me anyway. ;-). ade designed trellis QAM seems >>> like AM to me anyway. ;-). Imagine having really serious digital >>> voice over NVIS channels with S9 signals on 40 meters and running 5 >>> watts. Bring it on! >>> >>> >>> Bob >>> >>> >>> >>> DuBose Walt Civ AETC CONS/LGCA wrote: >>> >>> >>>> First, the NPRM was not strictly an ARRL proposal, in fact, it >>>> didn't appear to me to be the major proposal or proposal that the >>>> FCC used to draft the NPRM. >>>> >>>> Ok Bob, we know your views on CW, which are similar to my feelings, >>>> but what about the Board's decision to limit HF bandwidth to 3.5 >>>> KHz with a 9 KHz exemption for AM? Don't we need wider bandwidths >>>> for high-speed, robust data modes? Isn't the bandwidth limitation >>>> going to be a greater factor in hingering the growth of amateur >>>> radio than the Morse Code issue? >>>> >>>> Walt/K5YFW >>>> >>> >>> >>> >>> _______________________________________________ hfsig mailing list >>> hfsig at lists.tapr.org https://lists.tapr.org/cgi- >>> bin/mailman/listinfo/hfsig >> >> >> >> >> >> _______________________________________________ >> hfsig mailing list >> hfsig at lists.tapr.org >> https://lists.tapr.org/cgi-bin/mailman/listinfo/hfsig >> >> > > >
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