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Does phasing verticals work better than dipole?
First... what is phasing of verticals.
My 40 m dipole is only 30' up...would vertical phasing be an improvement? What would be the dimensions of the vertical and spacing distance? |
"bb" wrote in message ... First... what is phasing of verticals. My 40 m dipole is only 30' up...would vertical phasing be an improvement? What would be the dimensions of the vertical and spacing distance? probably. depends on how tall you can make verticals and if you can put enough radials under them. a square array of 4 vertical's 1/4 wavelength on a side can outperform a 2 element beam at 120' at some times on some paths, and most of the time on a few long paths in my experience. phasing 2 inverted L's can perform as well as and sometimes better than a single inverted V. just remember, the verticals probably won't be better close in, so when you compare them do it with stations that are a good distance away. |
bb wrote:
First... what is phasing of verticals. Essentially the same as phasing of horizontal elements. If you turn a 40m horizontal Yagi on it's side and bury half of it under a good ground plane, you have a vertical beam. My 40 m dipole is only 30' up...would vertical phasing be an improvement? Maybe, maybe not. At my QTH, the vertical noise is 2 s-units higher than the horizontal noise rendering any vertical antenna virtually unusable. No vertical that I have ever tried could overcome that -10 dB disadvantage. But your QTH could be entirely different from mine. It is possible, but not likely, that your vertical noise is lower than your horizontal noise. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil Moore wrote in message ...
bb wrote: First... what is phasing of verticals. Essentially the same as phasing of horizontal elements. If you turn a 40m horizontal Yagi on it's side and bury half of it under a good ground plane, you have a vertical beam. My 40 m dipole is only 30' up...would vertical phasing be an improvement? A single vertical would be an improvement over a dipole at 30 ft if working dx. Two phased would be even better. If you aren't working dx, but more close in stations within a few hundred miles, you would be better off phasing parallel dipoles for gain. A bit of gain nearly equal to a 2 el yagi, and about an average 20 db f/b. Maybe, maybe not. At my QTH, the vertical noise is 2 s-units higher than the horizontal noise rendering any vertical antenna virtually unusable. No vertical that I have ever tried could overcome that -10 dB disadvantage. But your QTH could be entirely different from mine. It is possible, but not likely, that your vertical noise is lower than your horizontal noise. If you are using the vertical for long haul, the increased received noise is a non issue. The signals will override the noise. IE: the noise might be 2 s units higher, but the signal increase over the low dipole will likely be more than that. The vertical still wins overall. Noise was never an issue when I used mine. The increased signals always overrode it by a good amount. You didn't see this because you didn't use yours for long haul. Many times my GP was nearly as quiet as the dipole. If there is no vertically polarized local noise, there is little difference between the two. At the moment I have three antennas on 160. An inv L, a top load vertical, and a Z dipole. All receive about equal noise as far as S meter reading. The dipole is just as noisy as the other two on that band. Only my indoor 16 inch small loop is really quiet...:/ MK |
Yes, phased verticals will outperform a dipole. The concept of phased
verticals involves two or more verticals, specifically spaced, and fed with specific lengths of feedline to control the phasing of the signals they're transmitting. Based on the spacing used, and the phasing arrangements, you can creat patterns of directed transmitted energy, just like a beam antenna - it *is* a beam antenna. Your best option now is to pick up a few books on basic antenna theory; I would suggest the ARRL Antenna Book, and Low-Band DXing by ON4UN... Mike KI6PR El Rancho R.F., CA "bb" wrote First... what is phasing of verticals. My 40 m dipole is only 30' up...would vertical phasing be an improvement? What would be the dimensions of the vertical and spacing distance? |
Mikey wrote:
Yes, phased verticals will outperform a dipole. Some phased verticals will outperform a dipole, depending upon how one defines "outperform". A dipole at a decent height can have a 7 dB gain over a 1/4 WL monopole. A two-element phased vertical cannot equal that figure over average ground. Reference: Fig 10, Chapter 8, The ARRL Antenna Book, 15th edition. The maximum gain figure for a two-element phased vertical is 4.7 dB over a 1/4 WL monopole. The average is about 3 dB depending on spacing and phasing. That same graphic is Fig 11, Chapter 8, on the ARRL Antenna Book CD, ver 2.0. EZNEC sez my simple 130 ft. dipole at 40 ft. has a gain of 10.8 dBi on 10m with a take-off-angle of 12 degrees. It would take quite a vertical array to equal that. (Then I would have to somehow overcome a +10 dB vertically polarized noise level. :-) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil Moore wrote in message ...
Mikey wrote: Yes, phased verticals will outperform a dipole. Some phased verticals will outperform a dipole, depending upon how one defines "outperform". It's more depending on the distance worked. A dipole at a decent height can have a 7 dB gain over a 1/4 WL monopole. His is at 30 ft. Yea, it might have 7 db max gain over the vertical. If he's working within 500 miles... A two-element phased vertical cannot equal that figure over average ground. Are you saying he should avoid radials, and use only the fairly lame "average ground"? No wonder none of your verticals work well... Cecil, I got news for you. A GOOD 2 el phased vertical setup would trounce a dipole at 30 ft at long distances past 1000 miles. A single GOOD vertical will beat the dipole on the same longer paths. Of course, I'm talking real verticals with the proper number of radials per height in wavelength, not some shortened loaded storebought junk, with no radials. Reference: Fig 10, Chapter 8, The ARRL Antenna Book, 15th edition. The maximum gain figure for a two-element phased vertical is 4.7 dB over a 1/4 WL monopole. The average is about 3 dB depending on spacing and phasing. That same graphic is Fig 11, Chapter 8, on the ARRL Antenna Book CD, ver 2.0. Gain fiqures are very misleading in this case. Tells only about half the story. You are causing more confusion than anything, because you don't properly apply the antennas to their proper jobs/paths. You never saw good results with yours because you misapplied it by using it for short paths, and also stunted it's performance by using too few radials. It never had a chance. EZNEC sez my simple 130 ft. dipole at 40 ft. has a gain of 10.8 dBi on 10m with a take-off-angle of 12 degrees. It would take quite a vertical array to equal that. (Then I would have to somehow overcome a +10 dB vertically polarized noise level. :-) What direction is all this gain? What will happen when you have to work someone in one of your nulls? Heck, I bet many of my old 5/8 ground planes would have equaled or beat your signal on 10m, to *most* people. I don't ever remember being beat by a simple dipole. In fact, when I used ground planes on 10m, I considered a horizontal dipole to generally be inferior. I know the ones I had were inferior to my ground planes at paths 1500-2000 miles away. And yes, some were long, and should have shown gain. They were over a wavelength high also. I wonder how your 10.8 dbi on 10m dipole would stack against my Cushcraft A4S beam? It has less gain according to the specs. But, I bet it beats your dipole on 10m in any direction if mounted at the same height. BTW, none of my 10m ground planes showed a 10 db increase in noise over my dipoles or other wire antennas. MK |
Mark Keith wrote:
You are causing more confusion than anything, because you don't properly apply the antennas to their proper jobs/paths. You never saw good results with yours because you misapplied it by using it for short paths, and also stunted it's performance by using too few radials. It never had a chance. I didn't say anything about my vertical, Mark. I merely quoted The ARRL Antenna Book and EZNEC results. Your (biased) argument is with them, not with me. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil Moore wrote in message ...
Mark Keith wrote: You are causing more confusion than anything, because you don't properly apply the antennas to their proper jobs/paths. You never saw good results with yours because you misapplied it by using it for short paths, and also stunted it's performance by using too few radials. It never had a chance. I didn't say anything about my vertical, Mark. I merely quoted The ARRL Antenna Book and EZNEC results. Your (biased) argument is with them, not with me. I guess so then. I know that applying that info to the real world will not really pan out on longer low band paths despite what models might say about gain at a certain lower angle. It's below 10 degrees or so that really counts to long dx. Biased? Maybe so. But at least I've actually used a good full sized elevated vertical to be able to make an accurate opinion. Over a three or four year time span I might add. It's not like I'm speculating or just barking at the moon. I made nightly comparisons. I nearly wore my antenna switch out switching back and forth. When on a long path at 1500 miles or farther, not a single time was the vertical "in my case elevated ground plane" ever beat by the dipole I had at 36 ft. Not one. Nada. Zip. And at that 1500 mile mark to CA., the vertical was always 2 S units better. Always! Of course, you have fading where the peaks of each polarization swap back and forth, but the peaks of the vertical were always 2 s units stronger than the peaks of the horizontal dipole. And this was reciprical. I didn't have to get on the air reports to see which antenna was better to a certain place. Yep, I guess you could call me biased...I'd even take this farther and speculate that the dipole even at a half wave "65 ft on 40m" would have trouble beating the elevated vertical I had on long paths. After all, it's going to have to come up an average of 4 S units "average report given to me over the 36 ft dipole" to a long DX haul site to do it. "IE: TX to VK land". Do you think raising the dipole from 36 ft to 65 ft will give me 4 more S units to VK land? Maybe, but I really doubt it myself. W8JI's tests of high 160m dipoles, vs tower verticals tends to back me up on this. Tom once said he thought a high 160m dipole would surely tromp over the verticals and he put one up. I think modeling told him it would be better. But it didn't pan out. I seem to recall him saying it was a waste of time and tower space.. Or something along those lines...If I add to add anything for the benefit of the original poster, it would be to consider the path length, when deciding which to use. If he doesn't work dx, he probably doesn't want a vertical. He'd be better off with a dipole array. If he does, he oughta try one. If it's a good vertical, he'll like it. My dipole is so lame compared to my GP on 40m late at night, I actually quit getting on the air at night after I took it down. Instantly dropping 4 s units to VK land is no fun. I still have the antenna on the side of the house though, if I ever feel the need to brown the food over there. The guys running bobtail curtains, "basically a vertical phased array" did even better than I did. They were the only ones that could beat me consistantly every night. And they were mounted on the ground to boot, compared to my GP at 36 ft. There is power in the number of elements...:) MK |
Mark Keith wrote:
Yep, I guess you could call me biased...I'd even take this farther and speculate that the dipole even at a half wave "65 ft on 40m" would have trouble beating the elevated vertical I had on long paths. But, Mark, you are neglecting physical efficiency. Divide the performance by the amount of metal required for each antenna and see what you get. :-) My dipole uses 1/2WL of wire. Your vertical uses how many wavelengths of wire? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
On Thu, 19 Feb 2004 05:29:16 -0600, Cecil Moore
wrote: But, Mark, you are neglecting physical efficiency. On 18 Feb 2004 22:15:35 -0800, (Mark Keith) wrote: After all, it's going to have to come up an average of 4 S units "average report given to me over the 36 ft dipole" to a long DX haul site to do it. "IE: TX to VK land". Hi Mark, The Flat Earth Socialists invent new forms of "efficiency" to argue against success. With their logic, a dummy load is the world's best antenna (and quiet too). The are obviously seduced by their own math models where less current emerges from a resistor than goes in. ;-) 73's Richard Clark, KB7QHC |
Richard Clark wrote:
The are obviously seduced by their own math models where less current emerges from a resistor than goes in. ;-) What does your lumped circuit math model say about resistors used on a frequency where the resistor plus its leads is 1/4WL long? At that frequency, why are you surprised that the current in is different from the current out (in the presence of standing waves)? Heck, I have seen a GDO find the resonant frequency of a resistor with the leads shorted together (that's the entire circuit). Do you think the current is the same everywhere in a resistor that is a 1/2WL loop? -- 73, Cecil, W5DXP |
On Thu, 19 Feb 2004 12:19:20 -0600, Cecil Moore
wrote: The are obviously seduced by their own math models where less current emerges from a resistor than goes in. ;-) What does your lumped circuit math model say about resistors I'm not interested in Flat Earth Socialist rhetoric. |
Richard Clark wrote:
I'm not interested in Flat Earth Socialist rhetoric. Looks like you are trying to delete and hide the fact that a resistor plus its leads has a resonant frequency that can be measured. At that resonant frequency, do you think the current is the same everywhere along the resistor and leads? Remember, you were scornful of such a concept. What I have done is presented a situation where lumped circuit theory totally falls apart as it does in physically large mobile loading coils. That's one reason that distributed network theory was invented. Flat Earth thinking equates to using lumped circuit theory for applications where it simply doesn't work. -- 73, Cecil, W5DXP |
On Thu, 19 Feb 2004 13:32:15 -0600, Cecil Moore
wrote: Richard Clark wrote: I'm not interested in Flat Earth Socialist rhetoric. Looks like you are trying to delete and hide Mark's experience eclipses this nonsense of Flat Earth Socialist rhetoric. |
Richard Clark wrote:
Mark's experience eclipses this nonsense of Flat Earth Socialist rhetoric. Mark hasn't tried a 130 foot dipole on 10m at the same height as his vertical in the direction of one of the four 11 dBi at 7 deg lobes. Even with a perfect ground, his vertical tops out at about 5 dBi, a full s-unit below the dipole's best lobes. Flat Earth thinking equates to asserting that a vertical monopole will beat a +11 dBi beam (or lobe). -- 73, Cecil, W5DXP |
Richard Clark wrote,
On Thu, 19 Feb 2004 13:32:15 -0600, Cecil Moore wrote: Richard Clark wrote: I'm not interested in Flat Earth Socialist rhetoric. Looks like you are trying to delete and hide Mark's experience eclipses this nonsense of Flat Earth Socialist rhetoric. Hi Richard, Cecil doesn't believe in measurement and experience. He's the last of the Scholastics. 73, Tom Donaly, KA6RUH |
On Thu, 19 Feb 2004 14:19:45 -0600, Cecil Moore
wrote: Richard Clark wrote: Mark's experience eclipses this nonsense of Flat Earth Socialist rhetoric. Mark hasn't tried You have tried even less = more nonsense of Flat Earth Socialist rhetoric. |
|
Tdonaly wrote:
Cecil doesn't believe in measurement and experience. He's the last of the Scholastics. If someone experiences a 5 dBi monopole beating a 11 dBi beam, I am skeptical. -- 73, Cecil, W5DXP |
On Thu, 19 Feb 2004 16:05:14 -0600, Cecil Moore
wrote: If someone experiences a 5 dBi monopole beating a 11 dBi beam, I am skeptical. Hi All, The statement above is the poster child of the lack of demonstrables. It is a binary comparison that leads to one of two conclusions based on incomplete discussion. In the linear world, there are many, many factors that go into judgemental determinations instead of these two rather threadbare characteristics that are only inferentially associated to a more profound observation. Such vague statements lead cfa proponents to claim their dipole designs whip standard FCC implementations of monopoles. Then when you examine the data, yup, the FCC design eclipses their generalities couched in neo-academia by 20 to 30dB. Such is the stuff of Flat Earth Socialism that huffs and puffs dusty tomes with speculations of long leaded resistors against the unequivocal evidence of peer judged field work. 73's Richard Clark, KB7QHC |
Cecil Moore wrote in message ...
Mikey wrote: Yes, phased verticals will outperform a dipole. Some phased verticals will outperform a dipole, depending upon how one defines "outperform". A dipole at a decent height can have a 7 dB gain over a 1/4 WL monopole. A two-element phased vertical cannot equal that figure over average ground. Reference: Fig 10, Chapter 8, The ARRL Antenna Book, 15th edition. The maximum gain figure for a two-element phased vertical is 4.7 dB over a 1/4 WL monopole. The average is about 3 dB depending on spacing and phasing. That same graphic is Fig 11, Chapter 8, on the ARRL Antenna Book CD, ver 2.0. EZNEC sez my simple 130 ft. dipole at 40 ft. has a gain of 10.8 dBi on 10m with a take-off-angle of 12 degrees. It would take quite a vertical array to equal that. (Then I would have to somehow overcome a +10 dB vertically polarized noise level. :-) Cecil, It is extremely hard to follow this thread as many comparisons are vague i.e. frequency, length of antenna e.t.c. You are not helping things when you talk of a 130 foot dipole and its use on ten meters. I think calling that antenna a dipole is misleading to say the least For ten meters I would call it something more than a dipole. To talk of a simple dipole having 10 db gain on this group is more than misleading it is an attempt to confuse. Can you imagine me entering the 160 metre discussion and discussing my collinear dipole in the vertical position as just a "simple " dipole and with no buried ground plane at that? If you are going to continue to compare antennas then the info must be factual and completely comparible or you do not have a legit comparison. I came in late but I read all the postings on this thread and the comparisons are all over the place and hard to follow, so back to what I was doing which is more productive. Have fun, will pop back later when the postings get to over 200. Art |
bb wrote:
"Would vertical phasing be an improvement? Vertical antennas launch waves along the surface of the earth. Vertical antennas tend to have a null directly overhead. According to B. Whitfield Griffith, Jr. in "Radio-Electronic Transmission Fundamentals", the field intensity at 10 miles from an antenna will be 1000X stronger at 0.5 MHz than at 5.0 MHz if the soil conductivity is 10 mmhos/m (sort of ordinary) and if the same power is being radiated on both frequencies. High attenuation of the groundwave at high frequencies was the reason frequencies above 1500 KHz were thought no good in the early days of radio. Sea water has a conductivity of about 5000 mmhos/m, or about 500X better than ordinary earth. So, the lower HF spectrum is good for some maritime and tropical broadcasting services in island areas. Antennas need to be located near the water`s edge to avoid excessive loss in traversing land to get to the water. Salt air is not the best environment for a shortwave broadcast station. Shortwaves traveling along the earth`s surface are severely attenuated. Though I worked for years in shortwave broadcasting, I never saw a shortwave broadcast station that used vertical polarization. Shortwave stations are usually sited away from the sea coast for protection and equipped with horizontal antennas to launch sky waves, not ground waves. The broadcaster wants to concentrate energy both horizontally and vertically to useful azimuths and elevation angles. These ideally are tailored to the broadcast target. The broadcaster gratefully accepts any useful reflection from the earth but does not tend to rely much upon it. There is no inviolable rule of one type or even of one polarization of antenna being best for all situations. There are many types. Kraus lists 24 types "as a preview to more detailed treatments." If you would really make your own discriminating choices instead of relying upon the advice of others, you would need to carefully study some book like Kraus` "Antennas". Best regards, Richard Harrison, KB5WZI |
Art, KB9MZ wrote:
"---the comparisons are all over the place and hard to follow." When the title reads: "Does phasing verticals work better than a dipole?" that could be expected to evoke confusing replies. Hams play antenna favorites, often when the favorites aren`t justified. I think it would be worth while to see what the most successful DXers actually use. ON4UN has tried to do this in "Low-Band DXing". Many use separate antennas for receiving and transmitting. The goal is signal to noise ratio on reception. The goal is effective radiated power on the target for transmission. Many Beverages are listed to receive the DX signal. At 80m, there are Yagis, slopers, Vees, etc. to transmit. At 160m, there are quite a few inverted Vees and other antennas which seem to trend to vertical polarization. The antennas may be too large to rotate and omnidirectionality may be accepted without so much struggle. Multiple directional transmitting antennas might be a better solution if the resources are available. You may only need a few hundred acres. Best regards, Richard Harrison, KB5WZI |
Cecil:
[snip] What I have done is presented a situation where lumped circuit theory totally falls apart as it does in physically large mobile loading coils. That's one reason that distributed network theory was invented. Flat Earth thinking equates to using lumped circuit theory for applications where it simply doesn't work. -- 73, Cecil, W5DXP [snip] As you well know 19th century electromagnetic field [EMAG] theory has been supplanted by modern 20th century quantum electro-dynamics QED, just as EMAG supplanted the circuit theory of the 18th century, and QED is "lumped" *not* "distributed". What??? Hey... give it up man! Distributed is passe... Even the latest Scientific American has an article on "Loop Quantum Gravity" the latest *lumped* physical theory, where the final three holdouts for the continuum and those discredited *distributed* theories, i.e. gravity, space, and time itself [i.e. Einstein's celebrated 20the century theory of general relativity] are now found to be "lumped" and are in fact comprised of purely discrete quanta. Time is not continuous or distributed but proceeds in tiny steps measured in Planck times of 10^-43 seconds. Space is also quantized in chunks of cubic Planck lengths of about 10^-99 cc's. See: Lee Smolin, "Atoms of Space and Time", Scientific American, January 2004, pp. 66-75. Quanta and lumps rule! -- Peter K1PO Indialantic By-the-Sea, FL [counting grains of sand on the beach today... :-)] |
Cecil Moore wrote in message ...
Richard Clark wrote: Mark's experience eclipses this nonsense of Flat Earth Socialist rhetoric. Mark hasn't tried a 130 foot dipole on 10m at the same height as his vertical in the direction of one of the four 11 dBi at 7 deg lobes. Even with a perfect ground, his vertical tops out at about 5 dBi, a full s-unit below the dipole's best lobes. Actually, I have tried it on 10m and most other bands. "I do have 80m dipoles". But no, the dipole never beat the 5/8 GP. I've also tried a 40m dipole. Flat Earth thinking equates to asserting that a vertical monopole will beat a +11 dBi beam (or lobe). It's like when I was out camping using a ladder line fed 80m, 130 ft dipole. I tried it on ten. It was pathetic due to the overly high takeoff angles. I'm talking terrible. We couldn't contact anyone, although we could hear a few. Bad...And yes, when modeled, that antenna had the same gain you claim with yours, being it was exactly the same. Lamest 10m antenna I ever used. My whip on the car beat it like a lost step child. In any direction. Like I said, gain numbers don't always tell it all. MK |
Cecil Moore wrote in message ...
Mark Keith wrote: Yep, I guess you could call me biased...I'd even take this farther and speculate that the dipole even at a half wave "65 ft on 40m" would have trouble beating the elevated vertical I had on long paths. But, Mark, you are neglecting physical efficiency. Divide the performance by the amount of metal required for each antenna and see what you get. :-) My dipole uses 1/2WL of wire. Your vertical uses how many wavelengths of wire? Good grief.....What an argument you have here, Cecil....Like the amount of wire used is pertinent to performance. But if you must know, my GP used 5 lengths of 1/4 wave material. The radiator being fully self supporting aluminum. The other four 1/4 wave lengths were of that high $$$$ stuff called wire. Really broke me that antenna did...:( MK |
Peter O. Brackett wrote:
QED is "lumped" *not* "distributed". What??? Hey... give it up man! Distributed is passe... Quanta and lumps rule! Well Peter, I have been trying to teach the Flat Earth engineers about the difference between movement of electrons and movement of photons but it hasn't made much of a dent in lumped concrete brains. Maybe you can say something about electron movement (dQ/dt) Vs the photons generated by the acceleration of those electrons. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Mark Keith wrote:
Actually, I have tried it on 10m and most other bands. "I do have 80m dipoles". But no, the dipole never beat the 5/8 GP. Fed with coax, and no doubt, laying on the ground. It's like when I was out camping using a ladder line fed 80m, 130 ft dipole. I tried it on ten. It was pathetic due to the overly high takeoff angles. I'm talking terrible. Perhaps, you had a cold solder joint (maybe on purpose so you could report what you are reporting?) Your results just don't make sense. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Mark Keith wrote:
Good grief.....What an argument you have here, Cecil... Good grief, Mark. Would you please learn what :-) means. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Richard Harrison wrote:
Art, KB9MZ wrote: "---the comparisons are all over the place and hard to follow." When the title reads: "Does phasing verticals work better than a dipole?" that could be expected to evoke confusing replies. Hams play antenna favorites, often when the favorites aren`t justified. I agree. Note what Cecil posts: "A dipole at a decent height can have a 7 dB gain over a 1/4 WL monopole. A two-element phased vertical cannot equal that figure over average ground." If you go by what Cecil says, you would get the impression a vertical, or vertical array would never have a chance over the dipole. Lets look at modeling with a clear head. The original posters dipole is at 30 ft. Ask Cecil to run that through the program and see where that 7dbi gain is at. Heck, I'll save all the trouble. It's at 89 degrees, or straight up. Whats the gain at 10 degrees? -4.32 dbi. 5 degrees? -10.17dbi. "using eznec over medium "real/high accuracy" ground" Whatta a dx buster. :( Lets run my 40m GP through the program. Same ground specs. Max gain is 4.38dbi at 11 degrees. At 10 degrees gain drops to 4.37dbi. No real change. At 5 degrees, 3.41 dbi gain. I don't know about you, but when working DX or any low angle path, I know which antenna I'll be using. See, even modeling "proves" what I say. :) But my real world results over a good period of time verify this. And others have also. W8JI for one. I have no real favorite, except as applies to a certain path. I always had BOTH a dipole and a vertical. Sure, in the day, I'd almost always be on the dipole. Out to about 800 miles or so, it was a draw. Could go either way. But over 1500 miles, no contest. The vertical was king of the hill. Believe me, if the dipole was actually better, I'd be the first to say so. I haven't even ventured into multi elements yet.. :/ Or the belief that any small extra noise really matters, when the DX signal increase almost always overrides it. You would only worry about the extra noise on the vertical if you were misapplying it and trying to work higher angle stateside stuff. I think it would be worth while to see what the most successful DXers actually use. True! I think you'll find most use verticals, or vertical arrays to transmit for the most part on the low bands. Many schemes are used for receiving. ON4UN has tried to do this in "Low-Band DXing". Many use separate antennas for receiving and transmitting. The goal is signal to noise ratio on reception. The goal is effective radiated power on the target for transmission. Many Beverages are listed to receive the DX signal. At 80m, there are Yagis, slopers, Vees, etc. to transmit. At 160m, there are quite a few inverted Vees and other antennas which seem to trend to vertical polarization. An inv Vee is still going to be mostly horizontal on that band, unless it's really high, and the legs are very steeply sloped. The antennas may be too large to rotate and omnidirectionality may be accepted without so much struggle. Multiple directional transmitting antennas might be a better solution if the resources are available. You may only need a few hundred acres. Size may well influence many to vertical on 160m due to space constraints. But, I'm still of the opinion that there is an advantage to vertical polarization at night on any band that the primary skip takes the dark path instead of day. I don't really think this applies to day paths too much though for some reason. BUT!, I still think vertical can do very well on the high bands. With a single element, it puts more of your power where you really want it. At low angles. Only on say 20m to stateside stuff might you use the higher angles a low dipole might provide. I do usually prefer a dipole on 20m for "average" use. But I usually prefer a 5/8 GP on 10m if I can't have a yagi. MK -- http://web.wt.net/~nm5k |
Cecil Moore wrote:
Mark Keith wrote: Actually, I have tried it on 10m and most other bands. "I do have 80m dipoles". But no, the dipole never beat the 5/8 GP. Fed with coax, and no doubt, laying on the ground. Yep, fed with coax, but being the mismatch wasn't that large in the real world, the loss shouldn't have been overly bad. Actually, I think it was nearly resonant. or under 3:1 anyway...The antenna was at 36 ft. Hardly on the ground. It's like when I was out camping using a ladder line fed 80m, 130 ft dipole. I tried it on ten. It was pathetic due to the overly high takeoff angles. I'm talking terrible. Perhaps, you had a cold solder joint (maybe on purpose so you could report what you are reporting?) Your results just don't make sense. Worked fine on 80 and 40. My results make sense to me. But I'm a flat earther. Well, unless I'm high up in a jet. Then I can tell it slightly curves a bit. But when I'm on the ground, the earth does seem fairly flat. So it must be...MK -- http://web.wt.net/~nm5k |
Art Unwin KB9MZ wrote:
Cecil, It is extremely hard to follow this thread as many comparisons are vague i.e. frequency, length of antenna e.t.c. You are not helping things when you talk of a 130 foot dipole and its use on ten meters. I think calling that antenna a dipole is misleading to say the least In the Marine Corps, they call this a cluster#$%^...MK -- http://web.wt.net/~nm5k |
Mark Keith wrote:
Lets run my 40m GP through the program. Same ground specs. Max gain is 4.38dbi at 11 degrees. At 10 degrees gain drops to 4.37dbi. Unfortunately, my 130 ft dipole at 50 ft. used on 10m shows 10 dBi gain at 10 degrees. I don't know about you, but, seems to me, 10 dBi at 10 degrees beats 4.37 dBi at 10 degrees unless you live in a different reality from me which is entirely probable. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Mark Keith wrote:
Yep, fed with coax, but being the mismatch wasn't that large in the real world, the loss shouldn't have been overly bad. Egads, that is the whole problem. The mismatch was terrible. It's like when I was out camping using a ladder line fed 80m, 130 ft dipole. I tried it on ten. It was pathetic due to the overly high takeoff angles. Absolutely false! The TOA of a 130 ft. dipole on 10m is about 10 degrees. MOM+physics, not your feelings, dictate that fact. But when I'm on the ground, the earth does seem fairly flat. So it must be...MK Yep, that's what the Catholic priests told Galileo so it must be true. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Mark Keith wrote:
Art Unwin KB9MZ wrote: Cecil, It is extremely hard to follow this thread as many comparisons are vague i.e. frequency, length of antenna e.t.c. You are not helping things when you talk of a 130 foot dipole and its use on ten meters. I think calling that antenna a dipole is misleading to say the least In the Marine Corps, they call this a cluster#$%^...MK Sorry, but in Texas, two wires are the same as two (conductive) poles. We conceive our poles as fishing poles, and go on from there. :-) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil wrote,
But when I'm on the ground, the earth does seem fairly flat. So it must be...MK Yep, that's what the Catholic priests told Galileo so it must be true. -- 73, Cecil http://www.qsl.net/w5dxp Careful, Cecil. The last time I wrote something like that I got an irate email from a fellow who accused me of Catholic-bashing. Actually, those Catholic priests knew the Earth is round, Aristotle told them so. They might have taken an assertion that the Earth wasn't the center of the universe with a grain of salt, though. 73, Tom Donaly KA6RUH |
Cecil Moore wrote:
Mark Keith wrote: Yep, fed with coax, but being the mismatch wasn't that large in the real world, the loss shouldn't have been overly bad. Egads, that is the whole problem. The mismatch was terrible. No, it wasn't terrible. Not by a long shot. But I'm sure height, surroundings, etc, etc influenced this outcome. On paper, yes, it *should* have been bad. This sure wasn't the problem in the next example. It's like when I was out camping using a ladder line fed 80m, 130 ft dipole. I tried it on ten. It was pathetic due to the overly high takeoff angles. Absolutely false! The TOA of a 130 ft. dipole on 10m is about 10 degrees. MOM+physics, not your feelings, dictate that fact. My feelings had nothing to do with it. My friend, who was the one that wanted to get on 10m in the first place, called people until he was blue in the face. Not a single one answered him. It was like all our signal was shooting off into space overhead. Which is what was happening for some reason. It wasn't excess tuner loss, because I always use the bare min inductance needed to tune. It wasn't the feedline. It was overly high angles of radiation. Probably because the antenna was fairly low. The TOA of a 130 ft dipole will depend on the height above ground. You state gain numbers, yet you don't ask how high the dipole I used was. It's the all important "missing link". The dipole we used was probably 15-20 ft off the ground. Model that on 10m at 20 ft and see how it looks. Probably even worse at 15 ft. Looking at the elevation plot, the angle of max gain is 24 degrees at 0 degrees azimuth angle, and 28 degrees at 90 degrees angle. I show negative gain "dbi" at all angles below 10 degrees. Compare this with a lowly 10m 1/4 wave GP at 8 ft off the ground. This leaves the sloping radials at 2.5 ft off the ground. Max gain is at 13 degrees. You don't see negative gain until 4 degrees or less. It will beat your gain-daddy dipole in most all directions on long low angle paths or ground/space wave I suspect. I know my mobile antenna trounced the one we used. MK -- http://web.wt.net/~nm5k |
Cecil Moore wrote:
Mark Keith wrote: Lets run my 40m GP through the program. Same ground specs. Max gain is 4.38dbi at 11 degrees. At 10 degrees gain drops to 4.37dbi. Unfortunately, my 130 ft dipole at 50 ft. used on 10m shows 10 dBi gain at 10 degrees. I don't know about you, but, seems to me, 10 dBi at 10 degrees beats 4.37 dBi at 10 degrees unless you live in a different reality from me which is entirely probable. -- 73, Cecil http://www.qsl.net/w5dxp Thats Cecil alright. I know it's not a sears imposter. Use his 10m specs to compare to my 40m specs...Totally valid comparison... Not...MK -- http://web.wt.net/~nm5k |
Cecil Moore wrote:
Mark Keith wrote: Art Unwin KB9MZ wrote: Cecil, It is extremely hard to follow this thread as many comparisons are vague i.e. frequency, length of antenna e.t.c. You are not helping things when you talk of a 130 foot dipole and its use on ten meters. I think calling that antenna a dipole is misleading to say the least In the Marine Corps, they call this a cluster#$%^...MK Sorry, but in Texas, two wires are the same as two (conductive) poles. We conceive our poles as fishing poles, and go on from there. :-) Actually, it's not calling it a dipole that bothers me...:/ MK -- http://web.wt.net/~nm5k |
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