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On Thu, 11 Oct 2007 11:21:29 -0700, Robert Smts wrote:
Frnak McKenney wrote: --snip-- On Tue, 09 Oct 2007 22:35:29 -0700, Robert Smts wrote: Frnak McKenney wrote: I'm in Richmond, Virginia and I'm trying to noticeably improve my reception of WWV's 10MHz signal from Fort Collins, Colorado. --snip-- Frank, can't you erect anything outside at all? A 10 metre dipole, is after all, only about 5 metres long. And if you can't do that, what kind of attic do you have? If your house is oriented correctly, you could even build a three element wire yagi pointed west inside the attic. --snip-- I definitely think I'm missing something, but then, I haven't really made it that far into the Antenna Handbook. Anyway, thanks for the suggestion. You're welcome. Your characterisation of the antenna as above is correct, and hopefully your attic is correctly oriented. Of course if you can put it outside, fixed wire beams are often very useful. If I'm following the ARRL handbook correctly, I want the elements laid out _across_ the incoming wavefront. For Fort Collins to Richmond, that is, going west to east, that would mean I'd want to string the wires/elements north-south. Naturally (per Murphy, the patron saint of Data Processing) my house is oriented E-W. Which does still, as you point out, leave the possibility of building something outdoors. Still, my current indoor loop seems to be picking up a nice strong signal. It was upright when I first started testing, but it wound up being laid flat at some point in the past few days -- about the time I discovered that I had been mis-tuining it. Wonder which had more effect: my changes, or atmospherics? grin! Anyway, thank you for your time and suggestions. I did some looking around on the 'web for introductory material to help me understand the ARRL Antenna Handbook and stumbled onto these: Antenna Newcomers and the Language of Antennas http://www.cebik.com/tales/nc.html Antennas from the Ground Up http://www.cebik.com/gup/groundup.html Some really nice propagation plots. Now, if there were just some simple way of figuring out which way the antenna is oriented relative to the plots... "It's an imperfect universe" grin! Frank -- Anyone who is not genuinely addicted to the search for knowledge is unlikely to have the psychological energy to be a true scholar in any field. But in history this work clearly resembles more that of a detective than that of a scientist -- a search for and judgment of particular evidence rather than a repeatable experiment. The detective side of historical research needs skill, background, and intuition. -- Robert Conquest, "The Dragons of Expectation" -- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all) |
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#2
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Frnak McKenney wrote:
If I'm following the ARRL handbook correctly, I want the elements laid out _across_ the incoming wavefront. For Fort Collins to Richmond, that is, going west to east, that would mean I'd want to string the wires/elements north-south. Naturally (per Murphy, the patron saint of Data Processing) my house is oriented E-W. Which does still, as you point out, leave the possibility of building something outdoors. You're following it correctly only if you're using elements which are no longer than about 5/4 wavelength. The direction of maximum gain isn't longer perpendicular to the wire if the wire is longer. This is covered very will in the _Antenna Book_. Still, my current indoor loop seems to be picking up a nice strong signal. It was upright when I first started testing, but it wound up being laid flat at some point in the past few days -- about the time I discovered that I had been mis-tuining it. Wonder which had more effect: my changes, or atmospherics? grin! As I mentioned in my other recent posting, there's no way for you to tell. Anyway, thank you for your time and suggestions. I did some looking around on the 'web for introductory material to help me understand the ARRL Antenna Handbook and stumbled onto these: Antenna Newcomers and the Language of Antennas http://www.cebik.com/tales/nc.html Antennas from the Ground Up http://www.cebik.com/gup/groundup.html Some really nice propagation plots. Now, if there were just some simple way of figuring out which way the antenna is oriented relative to the plots... "It's an imperfect universe" grin! You can duplicate the plots for the kinds of simple antennas you're dealing with, with the free demo version of EZNEC available from http://eznec.com. In the View Antenna display, select View/Objects, then check the "2D Display" box. Then you'll see a 2D plot superimposed on the view of the antenna, to show how the two are related. When viewing a 3D plot, the View Antenna display rotates along with the 3D pattern, so you can see how they're related if you keep both windows open. Roy Lewallen, W7EL |
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#3
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On Sun, 14 Oct 2007 17:20:32 -0700, Roy Lewallen wrote:
Frnak McKenney wrote: --snip-- Still, my current indoor loop seems to be picking up a nice strong signal. It was upright when I first started testing, but it wound up being laid flat at some point in the past few days -- about the time I discovered that I had been mis-tuining it. Wonder which had more effect: my changes, or atmospherics? grin! As I mentioned in my other recent posting, there's no way for you to tell. I noticed. Yesterday all those really clear tones and voice segments vanished while I wasn't paying attention. I can still hear enough WWV on occasion to know it's still there, but it's not even close to being strong enough to start the clock running. Anyway, thank you for your time and suggestions. I did some looking around on the 'web for introductory material to help me understand the ARRL Antenna Handbook and stumbled onto these: Antenna Newcomers and the Language of Antennas http://www.cebik.com/tales/nc.html Antennas from the Ground Up http://www.cebik.com/gup/groundup.html Some really nice propagation plots. Now, if there were just some simple way of figuring out which way the antenna is oriented relative to the plots... "It's an imperfect universe" grin! You can duplicate the plots for the kinds of simple antennas you're dealing with, with the free demo version of EZNEC available from http://eznec.com. In the View Antenna display, select View/Objects, then check the "2D Display" box. Then you'll see a 2D plot superimposed on the view of the antenna, to show how the two are related. When viewing a 3D plot, the View Antenna display rotates along with the 3D pattern, so you can see how they're related if you keep both windows open. Thanks for the pointer; I didn't knwo that there was a free version available. I'll check it out when I get a chance Frank -- "Don't be afraid to take a big step if one is indicated. You can't cross a chasm in two small jumps." -- David Lloyd George, British Statesman -- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all) |
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