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Hash: SHA1 In Klystron writes: Paul W. Schleck " wrote: Klystron writes: 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. [...] In your model, only a single axis of data is transmitted - the time of day. That seems like a great deal of infrastructure and energy consumption to transmit a single data quantity. The equivalent infrastructure for weather transmission (marine and air) is even more elaborate and expensive. Can you see that is an outrageously inefficient way to distribute a small quantity of information? Transmitting 50 kilowatts from a single site capable of covering most of North America, using groundwave propagation, independent of solar activity, is an "outrageously inefficient way to distribute a small quantity of information?" Well, I do hope that you are hurrying to write your Congressman to demand that the National Institute of Standards and Technology put an immediate end to this grave outrage, and profound waste of taxpayer's money that has been going on for decades. After all, what does the NIST know about technology, or useful communications? Perhaps as little as the engineers and marketers in the economically successful and useful product field of WWVB watches and clocks, in your estimation. 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. My understanding is that they use SMS for fairly trivial communications, like what they will have for lunch or where they will meet at the mall. A rough equivalence might be SMS users objecting to the use of the SMS system by people who are sitting at full-size computers or by people who have connected keyboards to their phone. If they were to complain that "typing" pidgin English (like "HOW R U?") with your thumbs on a tiny telephone keypad was the one true way to use SMS, then I think I could agree that there was an equivalence. You might ask those kids why they also use conventional e-mail, despite having SMS availability. I think you are underestimating the power of SMS. As for the comparison to E-mail, I don't have to ask, as journalists have already done so, including this recent article from Slate: http://www.slate.com/id/2177969/pagenum/all/ Simply put, young people find appeal in the immediacy of small, but low-latency messages sent in relatively large numbers over a long period of time, and the information transmitted is far more rich and meaningful that what you imply above. In many respects, this type of communication is not stilted or limited, but almost provides the immediacy of a conversation, without having to run up your voice minute charges or leave your other callers unable to reach you due to the long-term busy signal. Young people do still use E-mail, but in circumstances for which it is the better choice. They are not seeking some overall best "general purpose communications" to get their messages across to each other. 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. [...] Again, it is for the exchange of a single axis of data - geographic location. Please stop tying to pass off these single purpose, dedicated systems as examples of general purpose communications. I didn't realize that only "general purpose communications" were considered worthwhile. Your previous reply argued that it was undesirable to use such a low-speed technology as Morse code given that there were many higher-speed alternatives (faster by "orders of magnitude" you said). I replied to you that fastest is not always best. Other issues (previously enumerated by me) might actually dictate the choice of lower-speed communications as the best choice. I also don't see "general purpose communications" mentioned in Part 97. Many "single purpose, dedicated systems" are used by amateurs, and help fulfill amateur radio's Basis and Purpose. In many cases, a "single purpose" technology is far more useful than a misfit, one-size-fits-all, "general purpose" one. Before we make too many assumptions about an undefined term, perhaps you can describe what types of "general purpose communications" you would consider to be worthy goals for the Amateur Radio Service, and which "single purpose" technologies you would like to see eliminated? Would you also kindly define what is a "single axis of data," in terms familiar to those involved in communications engineering and technology? What, then, would be "multiple axes of data?" 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 My understanding is that Morse-based beacon identifications are read by computerized devices and are not "copied" by the pilots. I doubt that you could find very many current pilots who could copy any Morse at all. So, in other words, you are actually agreeing with my previous reply to you that there are many useful Morse code based communications technologies that do not actually require memorized, in-head, copy of Morse code. I'm glad that we agree on something. [...] 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." There is nothing about that that is unique to Morse. Any type of RF link would be usable in that way. Yes. That is somehow a point of disagreement between us? In what way? I did acknowledge that you could re-engineer the NCDXF beacon system with one that uses, say, PSK31, but the bandwidth and data rate limits would still remain. A PC with a soundcard would still be usable for that system, as you note. I'm sure that the author of Faros could also quickly adapt, and make a PSK31 version of his NCDXF beacon recording software package. 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? Hams used to deride digital communications as "pulse" and tell tales about the way that it squandered bandwidth. They made it out to be something along the lines of spark-gap. Look for articles about "pulse" communications in old (1960's and 70's) issues of QST and Popular Electronics. Considering the lead time needed to develop a new mode, I think it is unreasonable not to go back at least that far. I believe that the anti-digital curmudgeons delayed the implementation of digital modes by a matter of decades. It is interesting to note that the most widely used digital modes (for 2-way radio, not for broadcast) were developed either in Japan (Icom/JARL DV) or under the auspices of a police organization that has no ties to radio, except as consumers (APCO 25). Wow, these curmudgeons must have been very powerful and effective in their obstructionism if they undermined entire areas of communications technology development in this country over the last 30-40 years. I didn't realize that our national technology infrastructure was so inflexible and lethargic that it could not recover from these influences, even after so many decades. [...] Furthermore, if the only technologies that you believe should be saved from being thrown away are those at 14.4 kBaud and up, Can you point to something in my post that makes such a claim? Just the introduction to your previous article, where you directly compare the Baud rate of Morse code with that of "obsolete" telephone modems. You stated that their data rates differed by "orders of magnitude," implying that communications technologies that were "orders of magnitude" slower than telephone modems could be dismissed as obsolete. Following the natural extension of that argument, then the only technologies that could be favorably compared to such telephone modems, and meet your argued standard of non-obsolete, could only be realized on high VHF and up. As I argued previously, use and advocacy of Morse code has no bearing on the current deployment of such technologies, as no Morse code test has been required to access them for at least 17 years. The Technician-class license has existed for far longer, and has only a minimal Morse code examination. The only technology that I have derided as being too slow as to have value is Morse code that is sent by hand (less than 100 baud). So, to summarize: slow-speed (less than 100 baud) PSK31 : "Good" similar order-of-magnitude speed Morse code: "Bad" So, it's not the speed you object to, it's the use of Morse code? Couldn't you have just stated that, and not gone to the trouble of bringing in other arguments like speed and bandwidth, or whether a communications technology is sufficiently "general purpose" or not, regardless of whether something "general purpose" would be the best choice in a given circumstance? Just say that you don't like Morse code. Others would at least give you credit for honesty. The Navy shut down its VLF network on the grounds that the data rate was inadequate. Perhaps it is time for the amateur community to take a similar step. References please? A Google search returns no evidence that Navy stations like NAA in Cutler, Maine have gone off-line. Are you possibly thinking of their ELF experiments that were recently ended? Even if so, what competing technology is the Navy contemplating that will reliably contact our submarine fleet that has "gone deep" under many fathoms of RF-attenuating sea water? I also didn't realize that amateur radio had similar "networks" that would need to be shut down. 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. That last paragraph is incoherent. Could you rephrase it? Looked pretty coherent to me, but for your benefit, I'll dissect it in detail: "If you are saying that someone *else* should have developed these technologies ..." In other words, amateur radio has failed to meet some standard of technology development. Other people were somehow "wasting" their time doing other things. "... (other than you, of course) ..." What have you done to make amateur radio a better place? Have you written your Congressman? Petitioned the FCC? Worked in the communications engineering and technology field? Developed amateur radio software and hardware solutions? You seem to be knowledgeable on many technical subjects, including the history of that technology over many decades. Did you try to change things, or are you asserting that you did not have the skills or abilities to help do so, even working with others over many decades? "... and since they haven't, then someone *must* be blamed, ..." I was implying that you were seeking scapegoats, as it is easier to blame others than look in the mirror. "... well, you can't really dictate how the world should turn out without taking an active role to help make it that way." In other words, Lead, Follow, or Get Out of the Way. "Sidewalk Superintendents" have very little influence on society. What is your choice? Also, some people seem to confuse actual solutions to problems (whether in amateur radio, or on the newsgroups) with a contest over who can become the most "outraged." To quote Jim Kelley, AC6XG: "Outrage, and a buck-fifty, will get us exactly what?" -- 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) iD8DBQFH5r/66Pj0az779o4RAnicAJ9csNsCmha8ssxAArkza8p3pxwIhACfZ v4O BXSruHeICy8G0AOT+mCOhPo= =tMJk -----END PGP SIGNATURE----- |
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