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#11
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In article , Alun
writes: Fessenden demonstrated voice modulated spark operation as early as 1900. His methods have been verified by actual tests using replica transmitters and dummy loads. Fessenden transmitted voice over one mile during December 1900, possibly on the 12th, on Cobb Island, Maryland. Yep. You can even listen to re-creations of what it may have sounded like on-line. I posted the urls here some time back. By 1903, he had reached 50 miles. Of course in a way *almost all* spark transmitters use alternators, because except for simple spark coils, they *all* use AC generated by alternators... Fessenden's innovation was to use AC above the voice frequency range. Brilliant guy. Over 500 patents, in a variety of fields. Fessenden had a two-way transatlantic radiotelephone setup in operation by November of 1906 using alternator RF sources. The demo of Christmas Eve 1906 was repeated a week later (New Year's Eve). These events are well documented. As is DeForrest's later voice coverage of the New York yacht race, using a spark transmitter of the earlier type (no alternator) but using a regenerative detector with a triode tube. I can't remember when that took place, although it is in several books, but the triode (audion) patent discloses the regenerative detector and was issued in 1907, so the yacht race must have taken place around that period. Practical regenerative detection is generally credited to Armstrong in 1915. However, DeForest's use of voice communication at such an early date is another historic fact. Seems to me that Fessenden's transatlantic 2 way radiotelephone operation is the most significant of these early developments. Less than 5 years after Marconi claimed one-time one-way reception of a single coded letter, Fessenden had practical, repeatable, two-way voice transatlantic radio communications over a longer path, using much less power. 73 de Jim, N2EY |
#12
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#13
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N2EY wrote:
The original 1913 reason for technical qualifications was to prevent interference to nonamateurs caused by improper adjustment of amateur transmitters. How much interference to nonamateurs is caused by improper adjustment of amateur transmitters today? Reading the FCC enforcement letters, such interference today seems to be more a case of intentional modification of amateur equipment by a lawless few to operate on nonamateur frequencies. It seems that you have to violate rules "on purpose" several times before the FCC starts working on it. Modern equipment rarely causes problems (like excessive splatter or harmonics). I'm talking about stuff from the major manufacturers (Yeacomwood), not the "freeband" "linayes". And who hasn't, by mistake, operate the wrong mode in some subband? Like answering a foreign phone CQ on 7140? Oops... Most people will not make a habit of doing that, but once or twice over the years. The FCC realizes that errors do happen, and that most people will realize the error and correct it themselves without the FCC having to do anything about it. jgjyujklo;fgd |
#14
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Robert Casey wrote in message ...
N2EY wrote: The original 1913 reason for technical qualifications was to prevent interference to nonamateurs caused by improper adjustment of amateur transmitters. How much interference to nonamateurs is caused by improper adjustment of amateur transmitters today? Reading the FCC enforcement letters, such interference today seems to be more a case of intentional modification of amateur equipment by a lawless few to operate on nonamateur frequencies. It seems that you have to violate rules "on purpose" several times before the FCC starts working on it. I think it all comes down to complaints, too. Modern equipment rarely causes problems (like excessive splatter or harmonics). I'm talking about stuff from the major manufacturers (Yeacomwood), not the "freeband" "linayes". That's very true. And it raises the question of "why should hams have to know all sorts of theory stuff when the original reason for that knowledge is largely gone" (similar to the above anticodetest argument - and just as incomplete). And who hasn't, by mistake, operate the wrong mode in some subband? Me. I've *never* done that. Not by mistake, not intentionally either. Like answering a foreign phone CQ on 7140? Not even once. Oops... Most people will not make a habit of doing that, but once or twice over the years. Mistakes happen. But when you read the FCC enforcement letters, it becomes clear that mistakes, particularly technical ones, aren't really much of a problem anymore in the ARS. The FCC realizes that errors do happen, and that most people will realize the error and correct it themselves without the FCC having to do anything about it. That's why we have OOs. The OO program was instituted so that hams would find out about such problem from each other rather than FCC. 73 de Jim, N2EY |
#15
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On 4 Dec 2003 09:26:52 -0800, N2EY wrote:
Mistakes happen. But when you read the FCC enforcement letters, it becomes clear that mistakes, particularly technical ones, aren't really much of a problem anymore in the ARS. Technical mistakes were, and I would guess still are, handled by less formal warnings (a phone call or an Advisory Notice rather than a Notice of Violation or a Notice of Apparent Liability to Forfeiture, for instance) at least the first time around. Whatever works..... -- 73 de K2ASP - Phil Kane From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon |
#16
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N2EY wrote:
Robert Casey wrote in message ... N2EY wrote: The original 1913 reason for technical qualifications was to prevent interference to nonamateurs caused by improper adjustment of amateur transmitters. How much interference to nonamateurs is caused by improper adjustment of amateur transmitters today? Reading the FCC enforcement letters, such interference today seems to be more a case of intentional modification of amateur equipment by a lawless few to operate on nonamateur frequencies. It seems that you have to violate rules "on purpose" several times before the FCC starts working on it. I think it all comes down to complaints, too. Modern equipment rarely causes problems (like excessive splatter or harmonics). I'm talking about stuff from the major manufacturers (Yeacomwood), not the "freeband" "linayes". That's very true. And it raises the question of "why should hams have to know all sorts of theory stuff when the original reason for that knowledge is largely gone" Well, the FCC allows us to build and modify equipment for use on the ham bands, and it would be a good idea if we know what we are doing. At least be able to recognize things like wrong frequency (like out of band), severe harmonics, splatter, TVI, and such. Cell phone users don't have licenses, but they're not allowed to modify their equipment either. Same for CBers. A CBer isn't supposed to modify his radio to operate on 10m, but a ham could. It becomes a "ham radio set" and no longer a "CB set". If and when the FCC says "no homebrewing or modifying, off the shelf 'type accepted' rigs only, then the theory requirement gets weaker. I doubt the FCC would ever do that, as one of our reasons for existing is to encourage learning about radio and electronics. |
#17
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In article , Robert Casey
writes: And it raises the question of "why should hams have to know all sorts of theory stuff when the original reason for that knowledge is largely gone" Well, the FCC allows us to build and modify equipment for use on the ham bands, and it would be a good idea if we know what we are doing. Sure. Just like how the FCC allows us to send and receive Morse code on the ham bands, and it would be a good idea if we know what we are doing. Neither the use of Morse code nor the construction/modification of equipment is mandatory. Many hams enjoy amateur radio without doing either. At least be able to recognize things like wrong frequency (like out of band), severe harmonics, splatter, TVI, and such. Sure. Just like being at least be able to recognize most of the 43 symbols of the Morse Code when sent at the very slow speed of 5 wpm. Cell phone users don't have licenses, but they're not allowed to modify their equipment either. Same for CBers. A CBer isn't supposed to modify his radio to operate on 10m, but a ham could. Yet they often do just that. It becomes a "ham radio set" and no longer a "CB set". If and when the FCC says "no homebrewing or modifying, off the shelf 'type accepted' rigs only, then the theory requirement gets weaker. Usually such modifications require the high level of technical skill required to cut the blue wire or crush diode D17.... And such modifications are not mandatory at all. Most hams today use certified equipment, do they not? Which is more common on the amateur HF bands: hams using homebrew/seriously modified equipment, or hams using Morse code? Do you really think the written exams adequately test whether a ham can build or modify amateur radio equipment - particularly considering the wide range of bands, modes and technologies usable by hams? I doubt the FCC would ever do that, as one of our reasons for existing is to encourage learning about radio and electronics. IMHO they've been gradually watering down the theory tests for over 25 years. 73 de Jim, N2EY |
#18
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![]() "N2EY" wrote in message ... In article , Robert Casey writes: And it raises the question of "why should hams have to know all sorts of theory stuff when the original reason for that knowledge is largely gone" Well, the FCC allows us to build and modify equipment for use on the ham bands, and it would be a good idea if we know what we are doing. Sure. Just like how the FCC allows us to send and receive Morse code on the ham bands, and it would be a good idea if we know what we are doing. Bzzt, passing a code test is NOT required to use morse code on ALL ham bands. A "no-code" tech is free touse morse at whatever speed or skill level (or lack of skill level) one wants to. I have no recollection of anyone ever being cited by the FCC for "sloppy" or too slow a code speed. Have you? At least be able to recognize things like wrong frequency (like out of band), severe harmonics, splatter, TVI, and such. Sure. Just like being at least be able to recognize most of the 43 symbols of the Morse Code when sent at the very slow speed of 5 wpm. That isn't a requirement in terms of actual use of morse. Cell phone users don't have licenses, but they're not allowed to modify their equipment either. Same for CBers. A CBer isn't supposed to modify his radio to operate on 10m, but a ham could. Yet they often do just that. You know anyone that modified their cellphone? CBs we know about, cellphones...I doubt it. It becomes a "ham radio set" and no longer a "CB set". If and when the FCC says "no homebrewing or modifying, off the shelf 'type accepted' rigs only, then the theory requirement gets weaker. Usually such modifications require the high level of technical skill required to cut the blue wire or crush diode D17.... And such modifications are not mandatory at all. Most hams today use certified equipment, do they not? Certified against what? Which is more common on the amateur HF bands: hams using homebrew/seriously modified equipment, or hams using Morse code? Do you really think the written exams adequately test whether a ham can build or modify amateur radio equipment - particularly considering the wide range of bands, modes and technologies usable by hams? Did the novice test, even in 1960 adequuately do that? I say no, yet those novices were also free to "homebrew" or build it themselves. I doubt the FCC would ever do that, as one of our reasons for existing is to encourage learning about radio and electronics. IMHO they've been gradually watering down the theory tests for over 25 years. Frankly, the General test of 1960 wasn't all that theory difficult. Many of us just memorized some formulas and some circuit diagrams. Cheers, Bill K2UNK |
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