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#81
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John Smith wrote:
... Hmmm, from your statements, and text--if adhered to, most-certainly suggests, they must be following your advise, surely! The "alligators", or, i.e., stations which are all mouth and no ears ... However, I am willing to debate, argue, stand-behind, etc., all which I have said ... I actually HAVE built my antennas, and continue to do so ... indeed, my statement is, "Only lamers buy them." Regards, JS P.S. Just in case you wondered, yes, I did purchase a couple, in the early days ... Regards, JS |
#82
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RHF wrote:
This is Why I refer to Amateur Radio as "The Craft" : The Mastery* of the Body of Knowledge and Practices related to the Science and Art of Radio Operating. * All Praise Be To Them That Do. -but- that is not me : for i remain simply a plain old shortwave radio listener : who keeps his swling "k-i-s-a-p" = keep/ing it simply and practical I enjoy sending intelligence from point A to point B without wires. I enjoy making spikes (not Xmas trees) on my FSH-313. My work involves UHF FM transmitters of between 10 mW and 250 mW. These need to go 300-500 feet (flawlessly). This is very similar to my hobby (what I enjoy). I can't believe they pay me to do this. |
#83
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On Dec 28, 8:38*pm, Telamon
wrote: In article , *John Smith wrote: RHF wrote: [stuff] RHF, I have no bone to pick with you, don't fall victim to trolls here which just wish to "stir up chit", to mask their ignorance ... SNIP - Now that is funny. One Trolling idiot posting - a response to another trolling idiot "don't fall - victim to the Trolls". - - -- - Telamon - Ventura, California Ah Telamon - You know me all too well ~ RHF |
#84
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On Dec 29, 5:50*am, Dave wrote:
RHF wrote: This is Why I refer to Amateur Radio as "The Craft" : The Mastery* of the Body of Knowledge and Practices related to the Science and Art of Radio Operating. * All Praise Be To Them That Do. -but- that is not me : for i remain simply a plain old shortwave radio listener : who keeps his swling "k-i-s-a-p" = keep/ing it simply and practical - I enjoy sending intelligence from point A to point B without wires. *I - enjoy making spikes (not Xmas trees) on my FSH-313. *My work involves - UHF FM transmitters of between 10 mW and 250 mW. These need to go - 300-500 feet (flawlessly). -*This is very similar to my hobby (what I enjoy). -*I can't believe they pay me to do this. Dave - You Are One of The Lucky Ones. - enjoy ~ RHF |
#85
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RHF wrote:
On Dec 29, 5:50 am, Dave wrote: RHF wrote: This is Why I refer to Amateur Radio as "The Craft" : The Mastery* of the Body of Knowledge and Practices related to the Science and Art of Radio Operating. * All Praise Be To Them That Do. -but- that is not me : for i remain simply a plain old shortwave radio listener : who keeps his swling "k-i-s-a-p" = keep/ing it simply and practical - I enjoy sending intelligence from point A to point B without wires. I - enjoy making spikes (not Xmas trees) on my FSH-313. My work involves - UHF FM transmitters of between 10 mW and 250 mW. These need to go - 300-500 feet (flawlessly). - This is very similar to my hobby (what I enjoy). - I can't believe they pay me to do this. Dave - You Are One of The Lucky Ones. - enjoy ~ RHF . I do. Thanks. |
#86
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On Dec 27, 12:57*pm, John Smith wrote:
Billy Burpelson wrote: ... Say what? He said he "ain't here to be a ham", so why would he want to transmit? Well, consider me a "different type of ham." *In that, I always construct my antennas to receive the best signal for the application at hand, ALWAYS--transmitting is only a secondary consideration. *As, I have never found an antenna which has been found to receive the most efficiently fail to do so in xmit mode. *Given both xmitter and receiver have the same input impedances ... I do, frequently, see hams adjust the antenna, and its' type, for the xmitter--and the best readings which can be obtained in that mode. *I pay far more attention to how the antenna receives ... I can always crank up power on this end, should I ever find it necessary--I don't know what the guys capabilities on the other end is/are ... Regards, JS JS, Good Antenna Building Concept : You Can't Talk To Them -unless- You Can First Hear Them. ~ RHF |
#87
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RHF wrote:
... - Now that is funny. One Trolling idiot posting - a response to another trolling idiot "don't fall - victim to the Trolls". - - -- - Telamon - Ventura, California Ah Telamon - You know me all too well ~ RHF . Problem is, telemundo does not use the term "newsnet troll" correctly. His definition: "newsnet-troll = anyone not agreeing with me or pointing out inaccuracies in my text." Quite obviously, most here will appear as a troll, to telemundo ... sad, so very, very sad. :-( Regards, JS |
#88
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In article ,
John Smith wrote: RHF wrote: ... - Now that is funny. One Trolling idiot posting - a response to another trolling idiot "don't fall - victim to the Trolls". - Ah Telamon - You know me all too well ~ RHF . Problem is, telemundo does not use the term "newsnet troll" correctly. His definition: "newsnet-troll = anyone not agreeing with me or pointing out inaccuracies in my text." That is just a comprehension impaired interpretation. Quite obviously, most here will appear as a troll, to telemundo ... sad, so very, very sad. :-( You have a great imagination but you don't know how to usefully apply it. -- Telamon Ventura, California |
#89
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RHF wrote:
... JS, Good Antenna Building Concept : You Can't Talk To Them -unless- You Can First Hear Them. ~ RHF . Well, I'd like an antenna like this one (see URL, below.) He comes into my location in the low valley of CA like a door buster, from his secret location in NV. Jumping the high Sierra Mountains in a single leap! grin http://www.smeter.net/w6obb/antenna-farm.php Regards, JS |
#90
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Here's why antenna efficiency is important for transmitting but not for
HF receiving. First, the definition of efficiency: For a transmitting antenna, it's the fraction of the power applied which is radiated. The remainder is turned into heat. For receiving, it's the ratio of the power which is delivered to the receiver to the power which could be delivered to the receiver if the antenna had no loss. The efficiency of a given antenna is the same when transmitting and receiving. Sometimes people use "efficiency" to mean other things -- this is the meaning of the term in all antenna literature and texts. Consider this communications system: transmitter - antenna - propagation path - antenna - receiver - listener A receiver unavoidably adds noise to the received signal. So if no noise is injected in the propagation path, the signal/noise ratio is the ratio of the signal entering the receiver to the noise created by the receiver's input circuitry. This is generally the case at VHF and above. When receiver noise dominates, as above, increasing the receive antenna's efficiency increases the signal arriving at the receiver, so the signal/noise ratio improves. This allows you to hear the signal better. But it only works for VHF and above. HF is a different story. At HF, there's a lot of atmospheric noise (injected in the "propagation path" part of the system), and unless the receive antenna and receiver are exceptionally bad, the atmospheric noise is much greater than the noise created by the receiver. I mentioned a simple test in my last posting, to see whether this is the case -- just disconnect the antenna. If the noise level drops, atmospheric noise dominates. It's not hard to make a receiver that atmospheric noise will dominate with a 3 foot whip antenna at HF. So at HF where atmospheric noise dominates, the signal/noise ratio is the ratio of the signal entering the receiver to the atmospheric noise entering the receiver. Compare this to the situation described above for higher frequencies. Now let's see what happens when we improve the efficiency of an HF receiving antenna. Because both the signal and the dominant noise come from locations in front of (that is, on the transmit side of) the antenna, improving the efficiency of the antenna makes both the signal and noise greater in the same proportion when they arrive at the receiver. There's no improvement at all in the signal/noise ratio. The effect is the same as turning up the receiver volume control. The only way you can improve the signal/noise ratio is to somehow favor one over the other, such as by making the antenna directional. And an inefficient, directional antenna like a Beverage or small loop will nearly always enable you to hear better in some directions than an efficient, nondirectional antenna because directionality helps and inefficiency doesn't hurt. How about transmit antenna efficiency? The signal strength from the transmit antenna is proportional to the antenna's efficiency. (It also depends on other things, but I'm just talking about efficiency here.) So if the efficiency of the transmit antenna increases from, say, 33% to 66%, the power levels of the signals at the receive antenna and the receiver double, and there's no change to the received noise, on either HF or VHF and above. So improving the transmit antenna efficiency always improves the signal/noise ratio at the receiver, in this case by 3 dB. That's why you can hear bunches of HF stations with a very inefficient antenna, but they won't hear you if you try to transmit using that same antenna -- it's because the noise is injected into the system between you. And it's likely that you'll be able to hear stations just as well with the very inefficient antenna as with a much larger, efficient one. Roy Lewallen, W7EL |
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