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Stefan Wolfe wrote:
wrote in message ups.com... First let me say that, in amateur radio use, the term "CW", when used to mean a mode of radio communication, is universally defined as "Morse Code radiotelegraphy by means of an on-off keyed carrier". The literal "continuous wave" meaning does not apply. Stefan Wolfe wrote: wrote in message ups.com... The big question is whether the signals (keyed carrier vs. keyed audio tone) look different on a spectrum analyzer. If they don't, why should FCC care? I agree that it doesn't matter to the FCC as long is the keyed audio tone is coupled to the radio with EM waves such as with light (optoisolators), RF or wires (electrical connections). However, if you couple the keyed audio carrier acoustically, speaker-to-mike using only sound waves, then that is J3E and only permissible in the voice portion of the band. No, that's just not true - *IF* the rig and tone are clean enough. Problems arise when the tone is not a pure sinusoid, or the transmitter does not have adequate carrier- or unwanted sideband-suppression. But that's not what is being discussed here. Feed a Morse-Code-keyed audio tone that is a pure sinusoid into an SSB transmitter of sufficient quality, and the result is "CW". It doesn't matter how the tone gets into the transmitter, as long as the process doesn't introduce other tones or artifacts. If I were to whistle nearly pure sine waves (I am a good whistler, perhaps you have seen paintings of my mother :-)) in Morse code into the mike input, it might look like CW and sound like CW but it would really be J3E, hence illegal in the CW sub-bands. No, that's not true, unless the whistle isn't a pure sine wave. Using acoustic coupling (J3E), it becomes a slippery slope; first computer generated tones, then human whistling, then humming and before you know it, "talking" (di dah di dah etc.. and finally, "words" :-)) Not a slippery slope at all. All that matters is what it looks like to a spectrum analyzer. If the whistle is a pure sine wave, the output will be a single carrier. But if it's not a pure sine wave, the result will be spectrally different, and illegal. From a regulations standpoint, it does not matter how the signal is generated. What does matter is that it meets the standards of spectrum purity. Now you might argue that a simple "CW" transmitter using keyed Class C stages and vacuum tubes can be much simpler, more electrically efficient, and certainly more elegant than a newfangled computer-SSB-transceiver-kluge-setup, yet deliver a signal of equal quality. That's true - but it's a different issue. I give up. You keep talking about how the signal looks when it is *received*. No, I don't. I'm talking about what the signal produced by the transmitter looks like on a spectrum analyzer I keep talking about how the true A1A signal is supposed to be *transmitted* (your last paragraph is exactly that but you dismissed it). The basic point is this: FCC doesn't care *how* you generate a "CW" signal, as long as it meets the technical requirements. Part 97 is not concerned with how you receive, only how you transmit. Not "how" you transmit but "what" you transmit. The characteristics of the transmitted signal are what matters, not the technology used to generate it. I agree it is true that you can fool anyone on the receiving end as long as you can make the signal look like A1A on a spectrum analyzer. Not about fooling anyone. It's about meeting the technical requirements for signal quality. That might be difficult because the sidebands generated by breaking a CW "square" wave would be present on my A1A transmission and you would somehow have to re-create them on your SSB pure tone transmission that is keyed in your tightly filtered audio circuit. But re-check the definition of A1A and you will see that there is only one way to *transmit* it. Show us. Post the definition that says the way the signal is generated matters to FCC. And A1A is the only FCC definition of "CW". Show us. It is a moot point because tone generated data (as a sinusoidal "mark" in your SSB transmission) is legal everywhere that CW is legal. The same is not true of the voluntary band plans. It it is important to know the difference, even if you think the difference makes no difference so to speak. And I said that whistling CW into the mike is J3E voice, not A1A, and the only thing that separates it from being legal on the CW sub-bands is the way the data is coupled, not how it is received or transmitted. The way the data is coupled makes no difference. What matters are the characteristics of the transmitted signal. In practice, I don't think anyone could whistle into a mike so perfectly as to produce a "CW" signal that would be indistinguishable from one generated by more conventional means. But that's not the point. You completely missed all of my points. No, I simply pointed out your errors in interpretation of the rules. |
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#2
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wrote in message ups.com... Show us. I don't usually accept usenet challenges for cites since I have other things to do but what the hey, you seem like a decent guy so I made an exception: §97.3 Definitions. (c) The following terms are used in this Part to indicate emission types. Refer to §2.201 of the FCC Rules, Emission, modulation and transmission characteristics, for information on emission type designators. (1) CW. International Morse code telegraphy emissions having designators with A, C, H, J or R as the first symbol; 1 as the second symbol; A or B as the third symbol; and emissions J2A and J2B. M = Modulation Type N None A AM (Amplitude Modulation), double sideband, full carrier H AM, single sideband, full carrier R AM, single sideband, reduced or controlled carrier J AM, single sideband, suppressed carrier B AM, independent sidebands C AM, vestigial sideband (commonly analog TV) F Angle-modulated, straight FM G Angle-modulated, phase modulation (common; sounds like FM) D Carrier is amplitude and angle modulated P Pulse, no modulation K Pulse, amplitude modulation (PAM, PSM) L Pulse, width modulation (PWM) M Pulse, phase or position modulation (PPM) Q Pulse, carrier also angle-modulated during pulse W Pulse, two or more modes used X All cases not covered above N = Nature of modulating signal 0 None 1 Digital, on-off or quantized, no modulation 2 Digital, with modulation 3 Single analog channel 7 Two or more digital channels 8 Two or more analog channels 9 Composite, one or more digital channel, one or more analog X All cases not covered above I = Information type N None A Aural telegraphy, for people (Morse code) B Telegraphy for machine copy (RTTY, fast Morse) C Analog fax D Data, telemetry, telecommand E Telephony, voice, sound broadcasting F Video, television W Combinations of the above X All cases not covered above Note that, in general, every permitted CW emission is AM and has a "1" in the middle. Note that it must be in Morse (I assume you agreed with that). J2 (SSB) is allowed (for what it's worth) but note that it must be either keyed on/off or quantized (*digital*). Note that in no case is any form analog modulation permitted in the FCC definition. It may only be on/off keyed or "on/off" by digital modulation. Tones are analog transmissions. You cannot use the RTTY "mark" tone as FCC-defined CW. Checkmate. |
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#3
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Stefan Wolfe wrote:
wrote in message ups.com... Show us. I don't usually accept usenet challenges for cites since I have other things to do but what the hey, you seem like a decent guy so I made an exception: Thank you §97.3 Definitions. (c) The following terms are used in this Part to indicate emission types. Refer to §2.201 of the FCC Rules, Emission, modulation and transmission characteristics, for information on emission type designators. (1) CW. International Morse code telegraphy emissions having designators with A, C, H, J or R as the first symbol; 1 as the second symbol; A or B as the third symbol; and emissions J2A and J2B. M = Modulation Type N None A AM (Amplitude Modulation), double sideband, full carrier H AM, single sideband, full carrier R AM, single sideband, reduced or controlled carrier J AM, single sideband, suppressed carrier B AM, independent sidebands C AM, vestigial sideband (commonly analog TV) F Angle-modulated, straight FM G Angle-modulated, phase modulation (common; sounds like FM) D Carrier is amplitude and angle modulated P Pulse, no modulation K Pulse, amplitude modulation (PAM, PSM) L Pulse, width modulation (PWM) M Pulse, phase or position modulation (PPM) Q Pulse, carrier also angle-modulated during pulse W Pulse, two or more modes used X All cases not covered above N = Nature of modulating signal 0 None 1 Digital, on-off or quantized, no modulation 2 Digital, with modulation 3 Single analog channel 7 Two or more digital channels 8 Two or more analog channels 9 Composite, one or more digital channel, one or more analog X All cases not covered above I = Information type N None A Aural telegraphy, for people (Morse code) B Telegraphy for machine copy (RTTY, fast Morse) C Analog fax D Data, telemetry, telecommand E Telephony, voice, sound broadcasting F Video, television W Combinations of the above X All cases not covered above Note that, in general, every permitted CW emission is AM and has a "1" in the middle. If we're talking about the non-voice parts of the AM bands, I agree. Frequency-shift Morse is allowed elsewhere but that's a different issue. Note that it must be in Morse (I assume you agreed with that). Other codes are allowed, but if they are used, the designation is different because they are considered data modes. J2 (SSB) is allowed (for what it's worth) but note that it must be either keyed on/off or quantized (*digital*). Note that in no case is any form analog modulation permitted in the FCC definition. It may only be on/off keyed or "on/off" by digital modulation. Agreed - but that on-off keying may be accomplished in any way that results in the transmitted signal meeting the requirements. Tones are analog transmissions. You cannot use the RTTY "mark" tone as FCC-defined CW. Not if there's also a space tone. But that's not what's being discussed. If you have an SSB transmitter of good quality (meaning good carrier and unwanted sideband suppression), and you feed a sine wave audio tone into the audio input, the resulting RF output is a single carrier frequency. If you then turn the audio tone on and off with Morse Code timing, the result is a Morse Code keyed RF carrier that is no different than a Morse Code keyed RF carrier generated any other way. In the cited regulations, I see no mention of how the signal is generated, only what the resulting RF output characteristics are. Checkmate. By whom? ;-) 73 de Jim, N2EY |
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