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#21
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![]() Scott Dorsey wrote: wrote: My greatest fear is that the FCC will totally do away with code in it's testing requirements, which will logically lead to a mass spectrum reassignment to make more room for voice and we will likely loose our valuable spectrum space in the process. But once the last license goes to SK what's to stop the FCC from giving it all away? Well, one of the nice things about code is that you don't _need_ very much bandwidth. And with modern DSP you should be able to make IF filters even narrower than my old R-390... should be possible to cram hundreds of carriers into the space of one SSB channel. So true, and low bandwidth helps CW get though when SSB would be impossible. However, don't forget that CW can be done quite nicely with a cheap computer, some simple cables and some free software without learning it. I suppose that one could argue that a human ear can hear what a computer can't, but I'd be willing to argue that point in favor of the computer. I'll be willing to bet that there won't be much improvement over CW in the raw "get the message though under bad conditions" power with the new digital modes using the same bandwidth as CW. Simple is under-rated in my book. As an operating mode CW is alive and well and likely to stay, however it will be computer driven more and more as the art dies off and new blood is not required to learn it as well as the old. Change is neither good or bad, it's just change. -= Bob =- |
#22
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![]() "Leroy" wrote in message news ![]() On Wed, 27 Sep 2006 12:32:22 -0700, bob_deep wrote: I sometimes listen in on 10 meters but don't hear much there. A bit of CW every now and then, but not much of anything, usually. Maybe I'm listening at the wrong times? Or is it mostly vacant and just freebanders buying the 10 meter rigs? Has much to do with where we are in the sunspot cycle. A couple or three years from now 10 meters will start to be much busier. It's my misfortune I got my upgrade to General a year before the dead bottom of the cycle. At the age of 74 I'm just hoping to be around long enough to see what the high point in the cycle sounds like.(G) Harold KD5SAK |
#23
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![]() "Leroy" wrote in message news ![]() On Wed, 27 Sep 2006 12:32:22 -0700, bob_deep wrote: [SNIP] I was under the impression that CW would get through under worse conditions and/or with lower power requirements than other modes. Yes that can be true. They speak of PSK as being low power but that is only low transmit power. It takes more power to generate a 25w PSK signal than a 100watt CW signal. Computers draw a lot of power. Does no one run "flea power" anymore? There are a lot of QRP (low power) hobbyists. I sometimes listen in on 10 meters but don't hear much there. A bit of CW every now and then, but not much of anything, usually. Maybe I'm listening at the wrong times? Or is it mostly vacant and just freebanders buying the 10 meter rigs? Bad point in the sunspot cycle for 10 meters. It does open occasionally but not like it does at the peak of the sunspot cycle. Right now it is not open every day (although it may be open for a while each week). And the time of day it is open tends to be when people are working, doing errands after work, etc. Dee, N8UZE |
#24
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![]() wrote in message ps.com... Scott Dorsey wrote: wrote: My greatest fear is that the FCC will totally do away with code in it's testing requirements, which will logically lead to a mass spectrum reassignment to make more room for voice and we will likely loose our valuable spectrum space in the process. But once the last license goes to SK what's to stop the FCC from giving it all away? Well, one of the nice things about code is that you don't _need_ very much bandwidth. And with modern DSP you should be able to make IF filters even narrower than my old R-390... should be possible to cram hundreds of carriers into the space of one SSB channel. So true, and low bandwidth helps CW get though when SSB would be impossible. However, don't forget that CW can be done quite nicely with a cheap computer, some simple cables and some free software without learning it. I suppose that one could argue that a human ear can hear what a computer can't, but I'd be willing to argue that point in favor of the computer. Actually, you would lose such an argument. There are many hams who have proven that they can decipher better than the computer. The computer hardware or software requires the following characteristics in the received transmission to work: 1. A strong signal 2. No distortion on the signal such as occurs from aurora, meteor scatter, etc. 3. The code sent is nearly equal in quality to that sent by a computer. Some one using paddles may achieve that but if they are sending with a manual key or bug, that is highly unlikely. I have frequently been able to copy better than the computer and my code skills are quite modest. The only time it beats me is when the code meets the above three criteria and is too fast for me to copy. I'll be willing to bet that there won't be much improvement over CW in the raw "get the message though under bad conditions" power with the new digital modes using the same bandwidth as CW. Simple is under-rated in my book. I'm not sure I understand what you are saying here. Did you leave something out? As an operating mode CW is alive and well and likely to stay, however it will be computer driven more and more as the art dies off and new blood is not required to learn it as well as the old. Change is neither good or bad, it's just change. While change is neither good or bad, sometimes the results of change can be undesireable. Dee, N8UZE |
#25
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From: Dee Flint on Wed, Sep 27 2006 4:32 pm
wrote in message Scott Dorsey wrote: wrote: My greatest fear is that the FCC will totally do away with code in it's testing requirements, which will logically lead to a mass spectrum reassignment to make more room for voice and we will likely loose our valuable spectrum space in the process. But once the last license goes to SK what's to stop the FCC from giving it all away? Well, one of the nice things about code is that you don't _need_ very much bandwidth. And with modern DSP you should be able to make IF filters even narrower than my old R-390... should be possible to cram hundreds of carriers into the space of one SSB channel. The old R-390 was designed to work with 12 KHz SSB. Cram as much as you can...:-) Even so, at 300 Hz bandwidth per OOK CW there would be room only for 40 of them in 12 KHz bandwidth. :-) So true, and low bandwidth helps CW get though when SSB would be impossible. However, don't forget that CW can be done quite nicely with a cheap computer, some simple cables and some free software without learning it. I suppose that one could argue that a human ear can hear what a computer can't, but I'd be willing to argue that point in favor of the computer. Actually, you would lose such an argument. There are many hams who have proven that they can decipher better than the computer. The computer hardware or software requires the following characteristics in the received transmission to work: Dee, your judgement is based solely on available "morse decoder" equipment. Hardly state-of-the-art and not optimized for anything but strong signals with little distortion. Relatively cheap equipments on the market. One reason for not bothering with true state-of-the-art computer-aided decoding is that there isn't any ROI, no "return on investment" of trying to make such a thing. I have seen/heard one "intellectual exercise" by a programmer that DOES work well under distortion, weak signals, noise, etc. [there was some discussion about that in here a few years ago] That wasn't done for money-making purposes, just to see if it could be done with modern PC platforms. With a bit more work it could do quite well in terrible signal environments. That there's so little opening in the market is under- standable when you consider that NO other radio service but amateur bothers with OOK CW for communications. Well, not quite. The millions of keyless automotive key fobs now in use in the USA use OOK CW. But, that data rate is well above human comprehension. Some of the garage door openers and other remote 'security' transmitters also use OOK CW in a similar fashion. Now I grant you that those key fob transmitters can't "work DX on HF with CW" but then the ham rigs can't unlock automobiles either. :-) I have frequently been able to copy better than the computer and my code skills are quite modest. The only time it beats me is when the code meets the above three criteria and is too fast for me to copy. You mean you actually USE one of those cheap morse decoders? [ tsk, tsk... ] :-) I'll be willing to bet that there won't be much improvement over CW in the raw "get the message though under bad conditions" power with the new digital modes using the same bandwidth as CW. Simple is under-rated in my book. I'm not sure I understand what you are saying here. Did you leave something out? Only his last sentence is a bit vague. However, "simple" is what comprises the now-available-on-the-market decoders, all relativly cheap compared to what the COULD be. As an operating mode CW is alive and well and likely to stay, however it will be computer driven more and more as the art dies off and new blood is not required to learn it as well as the old. Change is neither good or bad, it's just change. While change is neither good or bad, sometimes the results of change can be undesireable. "Undesireable" for whom? A minority of amateur radio hobbyists of today or the future of amateur radio? Are you thinking that "the needs of the few outweigh the needs of the many?" That's not egalitarian just quite selfish. If the FCC eliminates the manual telegraphy test from US amateur radio license testing, it will NOT take away YOUR privileges of amateur radio operation. At worst it may cause you some emotional upset. [the FCC is not concerned with the emotional mental health of citizens, just regulation of US civil radio] Is there something "stopping" any new amateur licensee from taking up manual morse code skills now? I don't think so. There doesn't seem to be anything in last year's NPRM about "prohibition against radiotelegraphy." That NPRM only involves the manual telegraphy test for GETTING INTO amateur radio. Every single allocated mode in US amateur radio is OPTIONAL for any licensee to use within the defined scope of their license class. The only two bands where the FCC allocates ONLY "CW" is in 6 and 2 meter bands; no-code-test Technicians can use radiotelegraphy there. In fact, the FCC allocates manual radiotelegraphy on nearly EVERY amateur band, the full band not just some slices. If manual radiotelegraphy is so good-glorious-glamorous, why aren't more radio amateurs embracing it now? Just WHY do you feel compelled to argue for the retention of that manual telegraphy test and the retrograde "glamour" of it to hold back amateur radio? |
#26
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"Leroy" wrote in message
news ![]() I was under the impression that CW would get through under worse conditions and/or with lower power requirements than other modes. Various digital modes do better under low SNR conditions than CW, but they do require a computer at both ends to perform the encoding and decoding -- some people don't like that fact, that you seemingly need "more equipment" to work such modes than you do with CW. It's a bit of a red herring, however, in that these days pretty much every single amateur radio being sold commercially has a processor (computer) in it anyway, and while some are strictly for "control" (not modulation/demodulation), the percentage that does have raw number crunching power increases every day, and within a decade it's a fair bet that over 90% of all commerical amateur radios will use DSP techniques for modulation and demodulation. (Cell phone went to DSPs somewhere between 5-10 years ago now...) Does no one run "flea power" anymore? Absolutely they do, and it's a really cool part of the hobby... but for every 100 amateurs, I would guess that the number running QRP on a regular basis is about 1. ---Joel |
#27
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![]() "Joel Kolstad" wrote in message ... "Leroy" wrote in message news ![]() every 100 amateurs, I would guess that the number running QRP on a regular basis is about 1. ---Joel My sole experience with QRP was accidental. I had reduced power to 5 watts to tune to a different band (17 meters) and forgot to turn the power back up. As a result I found myself speaking to a Swiss ham form my southern Oklahoma shack with 5 watts and getting a reasonably good signal report. I realize that for real QRPers 5 watts is high power, but for me it was an unusual pleasure. Moreso because bad weather had me using an indoor dipole mounted on the wifes sewing room ceiling (about nine feet above the earth). Harold KD5SAK |
#28
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kd5sak wrote:
Has much to do with where we are in the sunspot cycle. A couple or three years from now 10 meters will start to be much busier. It's my misfortune I got my upgrade to General a year before the dead bottom of the cycle. At the age of 74 I'm just hoping to be around long enough to see what the high point in the cycle sounds like.(G) Man, do anything you can to stick around. It's going to be good, and 10M FM is just more fun than anything. Get a PRC-8 and take lots of vitamin C. I predict that this next peak is going to be a really good one, at least as good as '78 was. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#29
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![]() Dee Flint wrote: wrote in message I'd be willing to argue that point in favor of the computer. Actually, you would lose such an argument. I don't think so, at least under most common operating conditions. There are many hams who have proven that they can decipher better than the computer. The computer hardware or software requires the following characteristics in the received transmission to work: 1. A strong signal Signal to noise ratio would be important, to be sure, however with the proper application of some limited computing power I'm sure one could construct a detector that would work with seriously low SNR. It is amazing what DSP's can do now days.. 2. No distortion on the signal such as occurs from aurora, meteor scatter, etc. Again, I've seen spectral displays that clearly show CW transmissions that could *not* be heard. 3. The code sent is nearly equal in quality to that sent by a computer. Some one using paddles may achieve that but if they are sending with a manual key or bug, that is highly unlikely. Sending code is not in question. Surely a computer is able to open and close the keying faster than a transmitter can possibly transmit. Also, remember that the faster you key, the higher bandwidth your signal will require and the higher the SNR will theoretically need to be for it to be decoded at the receiving end. I have frequently been able to copy better than the computer and my code skills are quite modest. The only time it beats me is when the code meets the above three criteria and is too fast for me to copy. I would contend that the software you are using is not utilizing the inputted signal at it's full potential. I've seen audio processing techniques that could pull out inaudible signals that where more complicated than CW would be. I would also ask if you where copying random characters or where you able to "fill in the gaps" by using the context? The latter would be a very different problem for a computer to solve. I'll be willing to bet that there won't be much improvement over CW in the raw "get the message though under bad conditions" power with the new digital modes using the same bandwidth as CW. Simple is under-rated in my book. I'm not sure I understand what you are saying here. Did you leave something out? I'm saying that if you pick any digital mode, restrict the bandwidth to that of the CW signal with the same data rate, keep the SNR the same with the same error rates, CW will be about as good as you can get. Not bad for an operating mode that has been around as long as CW. |
#30
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![]() wrote in message oups.com... Dee Flint wrote: wrote in message I'd be willing to argue that point in favor of the computer. Actually, you would lose such an argument. I don't think so, at least under most common operating conditions. Define "common operating conditions". For a contester, common operating conditions often include murderous QRM. Yet contesting is common. I've always maintained that one can construct various scenarios such that there is one where the particular mode under discussion is "the best". For ragchewers, common operating conditions often include manually sent CW. There are many hams who have proven that they can decipher better than the computer. The computer hardware or software requires the following characteristics in the received transmission to work: 1. A strong signal Signal to noise ratio would be important, to be sure, however with the proper application of some limited computing power I'm sure one could construct a detector that would work with seriously low SNR. It is amazing what DSP's can do now days.. Yes and there are some very fine software programs already available. But even so they fail before the "EAR" fails, assuming a trained and experienced operator. 2. No distortion on the signal such as occurs from aurora, meteor scatter, etc. Again, I've seen spectral displays that clearly show CW transmissions that could *not* be heard. So I've seen displays of many types of signals that cannot be heard. That is an entirely different issue from distortion. When the auroras start playing, PSK (as an example) is so distorted that no matter how strong the signal, the computer cannot decipher it. If a CW signal is distorted but loud enough to hear, the human ear/brain combo can still decipher. 3. The code sent is nearly equal in quality to that sent by a computer. Some one using paddles may achieve that but if they are sending with a manual key or bug, that is highly unlikely. Sending code is not in question. Surely a computer is able to open and close the keying faster than a transmitter can possibly transmit. Also, remember that the faster you key, the higher bandwidth your signal will require and the higher the SNR will theoretically need to be for it to be decoded at the receiving end. Receiving is the issue. If the received code was manually sent, the computer often fails. I have frequently been able to copy better than the computer and my code skills are quite modest. The only time it beats me is when the code meets the above three criteria and is too fast for me to copy. I would contend that the software you are using is not utilizing the inputted signal at it's full potential. I've seen audio processing techniques that could pull out inaudible signals that where more complicated than CW would be. I''ve tested everyone I could find. I'm one of those people who gets pleasure out of trying all the new gadgets & software I can find and afford. I've also seen inaudible signals pulled out of all kinds. That's quite feasible when the bands are in good shape. Add a little thunderstorm activity, geomagnetic disturbances, solar flares, etc and the machine can't decipher them. It's not a matter of signal strength but a matter of signal quality. I would also ask if you where copying random characters or where you able to "fill in the gaps" by using the context? The latter would be a very different problem for a computer to solve. Yes it is a different matter. Humans definitely have the edge on "fill in the gaps". I'll be willing to bet that there won't be much improvement over CW in the raw "get the message though under bad conditions" power with the new digital modes using the same bandwidth as CW. Simple is under-rated in my book. I'm not sure I understand what you are saying here. Did you leave something out? I'm saying that if you pick any digital mode, restrict the bandwidth to that of the CW signal with the same data rate, keep the SNR the same with the same error rates, CW will be about as good as you can get. Not bad for an operating mode that has been around as long as CW. Ok, I understand. Actually many digital modes are, by their nature, narrower than CW already. You would have to open up the filter to get to the same bandwidth. Again the key item is quality of signal. For example, aurora induces phase shifts on PSK (phase shift keying) and makes it undecipherable. It also induces phase shifts in voice and CW. It gives the voice & CW signals a buzzy, raspy sound. Yet you can often understand voice when PSK is undecipherable. CW, when there is a phase shift, sounds like a series of buzzes but can still be copied if you are used to it. And yes CW does a fine job and will continue to be advantageous under certain conditions. Dee, N8UZE |
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