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#31
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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 |
#32
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![]() Joel Kolstad wrote: I think I'm pretty much in agreement with you... 5 WPM is not an unreasonable barrier to entry, and I don't particular oppose keeping it around, but I do think it seems awfully arbitrary, and this refelcts somewhat poorly on hams as a group trying to present themselves as modern and professional. Well, we agree that we should keep this requirement, but I don't agree that CW should seen as reflecting poorly on us hams. CW operation, albeit old fashion, remains a useful skill that I think should be encouraged. I do acknowledge that the new digital modes and computer based CW does make CW skills less necessary, but I don't think we should consider it old fashion or out of date. -= Bob =- |
#33
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#34
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![]() wrote in message ... On Tue, 03 Oct 2006 23:15:13 GMT, "U-Know-Who" wrote: Not if it keeps you off HF. but it doesn't tom you know that BTW, you never did say what you use the AL-80 for. Keeping warm in the winter? |
#35
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![]() U-Know-Who wrote: wrote in message ... On Tue, 03 Oct 2006 23:15:13 GMT, "U-Know-Who" wrote: Not if it keeps you off HF. but it doesn't tom you know that BTW, you never did say what you use the AL-80 for. Keeping warm in the winter? i don't own one you are showing that you can't or don't read the posts your coment very well |
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