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Hash: SHA1 In Klystron writes: wrote: [...] So if the word PARIS is sent 50 times in 1 minute, that minute is divided into 2500 dit times. Which is 41.66 bps. [...] It still seems like an awfully slow data rate. I have seen people throw 14400 Baud modems in the garbage because they considered them to be so slow as to be worthless. A data rate of 42 bps is about 3 orders of magnitude slower than that. Many types of communications vary over many orders of magnitude of information rate, yet are considered useful and up-to-date. For example, the Casio WaveCeptor on my wrist: http://www.eham.net/reviews/detail/2497 receives a ~ 1 Baud Pulse Position Modulated (PPM) signal from radio station WWVB in Fort Collins, Colorado, which transmits on 60 kHz. It takes about a minute to send the complete time code to synchronize my watch. Slow? Yes. Useful? Yes, very much so, especially when considering the coverage and reliability that can be obtained from such a low-bandwidth, groundwave-propagated, Very Low Frequency (VLF) signal. The watch only needs to receive the time code at most once per day, which it does so automatically in the early hours of the morning sitting on my desk or dresser. A faster data rate would require something other than a VLF signal, and would not improve much on the quality or usability of the communications. It would definitely increase the price. Witness the much greater success in the marketplace of WWVB-based watches versus more advanced, higher bandwidth, but much more expensive, "Smart Personal Object Technology" (SPOT) watches: http://www.spotstop.com One of the most current and widely used communications technologies among young people is cellular telephone text messaging: http://en.wikipedia.org/wiki/Text_messaging (sometimes also called "Short Messaging System" or SMS) According to this recent demonstration on the Tonight Show with Jay Leno: http://www.youtube.com/watch?v=AhsSgcsTMd4 the realizable data rates are comparable in order of magnitude to that of fast Morse code that can be sent and received by human operators. Just try telling a teenager with an SMS-capable cellular telephone that it should be thrown in the trash because it isn't fast enough, or isn't of sufficiently novel technology, and see his or her reaction. To give you an amateur radio example, the Automated Position Reporting System (APRS): http://www.aprs.org uses 1200 Baud AFSK packet. Faster, but still an order of magnitude slower than technologies you imply should be thrown out. Since APRS reports important, but compact, telemetry at periodic intervals, the technology meets the requirements of many users utilizing VHF radios and Terminal Node Controllers (TNC's). Again, substituting much higher data rates would really not improve the technology or better meet the requirements of the users which it serves. To even give you a Morse code example, consider the simplicity and effectiveness of the NCDXF beacons running on the HF bands: http://www.ncdxf.org/beacons.html A relatively low data rate On-Off Keyed (OOK) Morse Code signal is able to quickly convey to the listener the quality of the communications link, and required link budget, to various points around the globe. All that is needed to be transmitted is a station identification, and the same symbol (in this case the letter "V") sent at 10 dB power steps from 100 Watts to 0.1 Watt. Complex modulation/demodulation equipment to achieve "orders of magnitude" faster data rates would not only not fit on the HF bands, they would not seem to offer much improvement in the quality of the service. I suppose one could implement a beacon network using something like PSK31: http://www.psk31.com/ which might even be able to demonstrate realizable communications link budgets below 0.1 Watt. But even that advanced digital mode would only have data rates comparable to Morse code. Though the NCDXF beacon network is a Morse code service, note that Morse code knowledge is really not necessary to utilize it effectively. A synchronized time base and a chart of which station transmits at which time would enable very fast determination of the link budget to the beacon locations. If you can't remember what a "V" sounds like in Morse Code (". . . _" like the intro to Beethoven's Fifth Symphony), I suppose you could put that on the chart as well. After all, the use of similar charts are how pilots usually decode the Morse code identifications of aeronautical beacons. There are even a number of excellent software packages linked from the NCDXF site above that could automatically monitor the signals, decode the Morse, and record the quality of the communications paths over time. One such package is Faros: http://www.dxatlas.com/Faros/ one of many advanced signal processing software packages for amateur radio that exploits the ubiquitousness of of inexpensive personal computers with sound cards in most home ham "shacks." Focusing simply on information rate disregards other aspects of the communications and the channel over which it is transmitted. These important aspects include the bandwidth and propagation characteristics of the available channel, the complexity of the required transmitting and receiving equipment, the amount of data that needs to be transmitted, and how quickly and often it needs to be conveyed. Single-attribute measuring contests may be fun, even ego-boosting to some, but are really not very useful or impressive to those who actually design and use practical communications systems. It just seems inconsistent with the way that so many hams have fought tooth and nail to hold onto Morse and to hinder the move toward digital modes. I'm not sure that I understand your line of reasoning here. You are implying cause-and-effect. In other words, use and advocacy of Morse code somehow directly contributed to the obstruction of other technologies. Can you give direct evidence of specific examples? If you are implying that licensing requirements obstructed the development of advanced digital modes, that really doesn't appear to be the case. Witness the success of Tucson Amateur Packet Radio (TAPR): http://www.tapr.org and the Radio Amateur Satellite Corporation: http://www.amsat.org which have developed or championed many promising digital technologies, developed by amateurs with widely varying degrees of Morse code operating skills. Furthermore, if the only technologies that you believe should be saved from being thrown away are those at 14.4 kBaud and up, those technologies are only practically realizable on amateur radio bands at high VHF and up. Such bands have been open to licensees without need of a Morse code test for going on 17 years now. Even before then, these bands were accessible to Technician-class amateurs since at least shortly after World War II, with a license that only required a minimal, 5 WPM (essentially individual character-recognition) Morse code test. If you are saying that someone *else* should have developed these technologies (other than you, of course), and that since they haven't, then someone *must* be to blame, well, you can't really dictate how the world should turn out without taking an active role to help make it that way. -- Klystron - -- 73, Paul W. Schleck, K3FU http://www.novia.net/~pschleck/ Finger for PGP Public Key -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (SunOS) iD8DBQFH5epg6Pj0az779o4RAvfbAJ4kewTvCX5mqHimGwfXkK tQCusKFwCgxKPZ ovhE2D69Thi8oiiqsv5I9X8= =4RMi -----END PGP SIGNATURE----- |
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