|
Why?
Antennas seemed to have evolved into structures that
are parallel or at right angles to the earths surface Why is this or is it asthetics that is driving this thinking? My research on the subject evolves around the vector formation of radiation and where the addition of the vectors involved which creats radiation is at an angle to the radiator.. This suggests that for best radiative advantage it is this vector that should be parallel to the earths surface and not the physical radiator. This appears to be born out by following my Gaussian approach to radiator design. So the question of habitual arrangement of antenna arrays parallel or at right angles to the earths surface as being the best arrangement needs some sort of validation. Any thoughts as to why it should be so and the scientific facts that support it? Art |
Why?
"art" wrote in message ups.com... Antennas seemed to have evolved into structures that are parallel or at right angles to the earths surface Why is this or is it asthetics that is driving this thinking? My research on the subject evolves around the vector formation of radiation and where the addition of the vectors involved which creats radiation is at an angle to the radiator.. This suggests that for best radiative advantage it is this vector that should be parallel to the earths surface and not the physical radiator. This appears to be born out by following my Gaussian approach to radiator design. So the question of habitual arrangement of antenna arrays parallel or at right angles to the earths surface as being the best arrangement needs some sort of validation. Any thoughts as to why it should be so and the scientific facts that support it? Art yes, there are many... but none that you will want to hear. |
Why?
"art" wrote in message ups.com... Antennas seemed to have evolved into structures that are parallel or at right angles to the earths surface Why is this or is it asthetics that is driving this thinking? My research on the subject evolves around the vector formation of radiation and where the addition of the vectors involved which creats radiation is at an angle to the radiator.. This suggests that for best radiative advantage it is this vector that should be parallel to the earths surface and not the physical radiator. This appears to be born out by following my Gaussian approach to radiator design. So the question of habitual arrangement of antenna arrays parallel or at right angles to the earths surface as being the best arrangement needs some sort of validation. Any thoughts as to why it should be so and the scientific facts that support it? Art What angle did you derive was the best angle to mount an anenna? Please show experimental data to backup your conclusions. Jimmie |
Why?
On Mon, 26 Mar 2007 22:27:13 -0400, "Jimmie D"
wrote: "art" wrote in message oups.com... Antennas seemed to have evolved into structures that are parallel or at right angles to the earths surface Why is this or is it asthetics that is driving this thinking? My research on the subject evolves around the vector formation of radiation and where the addition of the vectors involved which creats radiation is at an angle to the radiator.. This suggests that for best radiative advantage it is this vector that should be parallel to the earths surface and not the physical radiator. This appears to be born out by following my Gaussian approach to radiator design. So the question of habitual arrangement of antenna arrays parallel or at right angles to the earths surface as being the best arrangement needs some sort of validation. Any thoughts as to why it should be so and the scientific facts that support it? Art What angle did you derive was the best angle to mount an anenna? Please show experimental data to backup your conclusions. Jimmie Oh, and don't forget to correlate that angle to include the effects of local objects, terrain, and other variables so that everyone can construct THIER antennas to match the ascetic ideal of similarly aligned angles of radiation -- Raymond Sirois - KU2S http://www.hamxam.org 10-10 #70270 |
Why?
Art wrote:
"Any thoughts as to why it sgould be so and the scientific facts to support it?" We have plumb lines and bubble levels which allow easy determination of vertical and horizontal directions. We often inhabit a nearly horizontal plane If we are as likely as not to communicate with any particular direction, an omidirectional vertical antenna makes sense. An inclined wire would favor some direction to the detriment of another. Sure a slopimg wire works but doesn`t reach maximum height or length as effectively as a vertical or horizontal wire would. Why a straight dipole and not a V-shaped element? The V-shape corrupts the nulls at the ends of the straight wire. Vertical and horizontal antennas are not solely accidents of history. Best regards, Richard Harrison, KB5WZI |
Why?
On 26 Mar, 21:49, (Richard Harrison) wrote:
Art wrote: "Any thoughts as to why it sgould be so and the scientific facts to support it?" We have plumb lines and bubble levels which allow easy determination of vertical and horizontal directions. We often inhabit a nearly horizontal plane If we are as likely as not to communicate with any particular direction, an omidirectional vertical antenna makes sense. An inclined wire would favor some direction to the detriment of another. Sure a slopimg wire works but doesn`t reach maximum height or length as effectively as a vertical or horizontal wire would. Why a straight dipole and not a V-shaped element? The V-shape corrupts the nulls at the ends of the straight wire. Vertical and horizontal antennas are not solely accidents of history. Best regards, Richard Harrison, KB5WZI But the question is why? If you read thru the antenna handbooks they use vectors extensively but when it gets to take off angle there is no vectorial explanation of what determines TOA. I would like to see a vectorial explanation for TOA starting off with the two vectors eminating from the radiator which are relavent to the radiator angle with respect to earth. I also would like to see vectors that emulate propagation advantages following earths magnetic lines as apposed to those at right angles but as yet I have not tracked any down in the books. You refer to horizontal anternnas as not being "accidental" suggesting mathematical analysis yet I am not finding any documented proof other than emperical work. Time and time again this group will provide long threads regarding the mathematics of SWR, virtual this and that, tower wind loading, frequency, dielectrics yet when it comes to the very basics of a current passing along a conducor as a vector or just plain mathematics every bodies eyes just go blank. Is this something that is to hard to demonstrate or something hams don't care about until it is written in a book which we can then regurgitate? Art |
Why?
art wrote:
On 26 Mar, 21:49, (Richard Harrison) wrote: Art wrote: "Any thoughts as to why it sgould be so and the scientific facts to support it?" We have plumb lines and bubble levels which allow easy determination of vertical and horizontal directions. We often inhabit a nearly horizontal plane If we are as likely as not to communicate with any particular direction, an omidirectional vertical antenna makes sense. An inclined wire would favor some direction to the detriment of another. Sure a slopimg wire works but doesn`t reach maximum height or length as effectively as a vertical or horizontal wire would. Why a straight dipole and not a V-shaped element? The V-shape corrupts the nulls at the ends of the straight wire. Vertical and horizontal antennas are not solely accidents of history. Best regards, Richard Harrison, KB5WZI But the question is why? Because except for some very specialized applications there is nothing to be gained by using anything other than horizontal or vertical elements and it is the simplest way to make things. Have you ever heard of a helix? snip crap -- Jim Pennino Remove .spam.sux to reply. |
Why?
Art wrote:
"---yet I am not finding any documented proof other than emperical work." As usual, Terman has answers. See page 882 of his 1955 opus: "Effect of Ground on the Directional Pattern of Ungrounded Antennas - Image Antennas." It`s in the book; math, diagrams, tables, as needed to imagine what happens. Best regards, Richard Harrison, KB5WZI |
Why?
Jim Pennino wrote:
"Have you ever heard of a helix?" Most would likely enjoy Kraus` story of his invention of the axial-mode helix in his 3rd edition of "Antennas". This is a choice book! Best regards, Richard Harrison, KB5WZI |
Why?
On 27 Mar, 10:20, (Richard Harrison) wrote:
Jim Pennino wrote: "Have you ever heard of a helix?" Most would likely enjoy Kraus` story of his invention of the axial-mode helix in his 3rd edition of "Antennas". This is a choice book! Best regards, Richard Harrison, KB5WZI I have his second edition and I find no mention of radiation from the beginning where current is applied onwards. Have you found anything that can contribute other than empirical grounds? You have avoided the question so far |
Why?
On 27 Mar, 09:55, (Richard Harrison) wrote:
Art wrote: "---yet I am not finding any documented proof other than emperical work." As usual, Terman has answers. See page 882 of his 1955 opus: "Effect of Ground on the Directional Pattern of Ungrounded Antennas - Image Antennas." It`s in the book; math, diagrams, tables, as needed to imagine what happens. Best regards, Richard Harrison, KB5WZI Thank you for that I will get right on it. I presume it does give direct relationships between electrical and magnetic vectors relative to the conductor and ground ! |
Why?
Richard Harrison wrote:
Jim Pennino wrote: "Have you ever heard of a helix?" Most would likely enjoy Kraus` story of his invention of the axial-mode helix in his 3rd edition of "Antennas". ' "No," he replied, "I've tried it and it doesn't work."' |
Why?
On 27 mar, 19:47, "art" wrote:
On 27 Mar, 10:20, (Richard Harrison) wrote: Jim Pennino wrote: "Have you ever heard of a helix?" Most would likely enjoy Kraus` story of his invention of the axial-mode helix in his 3rd edition of "Antennas". This is a choice book! Best regards, Richard Harrison, KB5WZI I have his second edition and I find no mention of radiation from the beginning where current is applied onwards. Have you found anything that can contribute other than empirical grounds? You have avoided the question so far Hello Art, Radiation from accelerating charge is fully understood (from theory and verified practically), hence antenna theory. When you take the complete formula for fields (near and far) generated by a short wire segment (hertzian dipole), you can calculate the far and near field (magnitude, orientation, phase, etc) from every construction. The only problem is that you have to know the current distribution in your construction. It is not of interest whether the charge is excited by just a voltage source or EM radiation (like in reflection of waves on conductors and dielectrics). This is done in many FEM programs. Of course in many practical circumstances it is easier to use the "laws" from other people (that are derived from basic theory). One of the results are the Fresnel formulas for reflection. When you know the properties of the soil at the operating frequency, you can calculate the complex surface impedance and hence the complex reflection coefficient. Just mentioning words as "curl", "vector", "Gaussian" etc, doesn't make sense without further information. Best Regards, Wim |
Why?
On 27 Mar, 12:22, "Wimpie" wrote:
On 27 mar, 19:47, "art" wrote: On 27 Mar, 10:20, (Richard Harrison) wrote: Jim Pennino wrote: "Have you ever heard of a helix?" Most would likely enjoy Kraus` story of his invention of the axial-mode helix in his 3rd edition of "Antennas". This is a choice book! Best regards, Richard Harrison, KB5WZI I have his second edition and I find no mention of radiation from the beginning where current is applied onwards. Have you found anything that can contribute other than empirical grounds? You have avoided the question so far Hello Art, Radiation from accelerating charge is fully understood (from theory and verified practically), hence antenna theory. When you take the complete formula for fields (near and far) generated by a short wire segment (hertzian dipole), you can calculate the far and near field (magnitude, orientation, phase, etc) from every construction. The only problem is that you have to know the current distribution in your construction. It is not of interest whether the charge is excited by just a voltage source or EM radiation (like in reflection of waves on conductors and dielectrics). This is done in many FEM programs. Of course in many practical circumstances it is easier to use the "laws" from other people (that are derived from basic theory). One of the results are the Fresnel formulas for reflection. When you know the properties of the soil at the operating frequency, you can calculate the complex surface impedance and hence the complex reflection coefficient. Just mentioning words as "curl", "vector", "Gaussian" etc, doesn't make sense without further information. Best Regards, Wim- Hide quoted text - - Show quoted text - Wim I accept all of what you write . I can get the angle from computor programs based on Maxwell. but the computor program is not enough! I would like to see a mathematical proof of the tip angle required of a vertical to provide a wave front at 90 degrees to the tip angle. I see graphs of tip angles for a long legged "v" in Terman but not for a simple vertical or horizontal radiator. Can you point me to a paper that burrows deeply into this question either over a perfect ground or in free space? Art |
Why?
On 27 Mar 2007 10:51:27 -0700, "art" wrote:
I presume it does give direct relationships between electrical and magnetic vectors relative to the conductor and ground ! Hi Art, As this is all very elementary stuff, of course Terman does. 73's Richard Clark, KB7QHC |
Why?
Art wrote:
"I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI |
Why?
On 27 Mar, 15:12, (Richard Harrison) wrote:
Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art |
Why?
|
Why?
Art wrote:
"Could you quote from the books that you are referring to the angle relative to the radiator, that`s it?" O.K.. but the angle is relative to the horizontal in the statement. Termans 1955 opus on page 804 says the strength of radiation from a short vertical antenna is proportional to the cosine of the elevation angle. That`s right because at zero angle, radiation is maximumm as cosine of zero degrees is 1, and cosine of 90 degrees is zero. Best regards, Richard Harrison, KB5WZI |
Why?
Richard Clark, W7QHC wrote:
"-you know, the basic stuff of propagation." I may be able to respond to a question, but I don`t write books. On the question of ground conductivity and polarization: Soil loss makes vertically polarized waves tilt forward in the direction of their travel as if dragging their feet. It`s not all bad as this tilt makes a horizontal antenna, the Beverage, receive these vertically polarized waves well. Best regards, Richard Harrison, KB5WZI |
Why?
On 27 Mar, 15:12, (Richard Harrison) wrote:
Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. snip. Being uncertain of what Art really wants, doesn`t stop me from advising snip Bingo Just as I thought, you are bull****ting like the rest of them. All you have is the answer for the question you want me to ask so you can then look good. When you give that same answer to any question that I actually ask it sure removes any possible credability. If you all had been nice to the MIT guy he may have come back and give you a tutorial again to set you straight, but I suspect he left for the same reasons that other experts left. I accept that none on the thread has a clue so it is reasonable to close down this thread to allow you to get back to badger Walt. I believe that each poster has provided an average of ten posts on Walt's article which suggest that Walt is having a bad time with communicating his message like me. My bet is that half of the posts aren't even relavent to the subject at hand! That's tough for anybody.Richard you have posted four times with lots of words on this thread but at the very end you admit that you have no idea what the thread was all about. So what were your answers meant to apply to so I can oblige you with supplying the question that you want... to the answer you have already so you can spout off. No ........forget it. ............FINI.......... Art Best regards, Richard Harrison, KB5WZI |
Why?
I readily admit I have not discovered whhat Art asked for. My first
guess was: Why are most antennas either horizontal or vertical. I tried to give a thoughtful and honest answer. Sorry it didn`t satisfy. Best regards, Richard Harrison, KB5WZI |
Why?
"Richard Harrison" wrote in message ... I readily admit I have not discovered whhat Art asked for. My first guess was: Why are most antennas either horizontal or vertical. I tried to give a thoughtful and honest answer. Sorry it didn`t satisfy. Best regards, Richard Harrison, KB5WZI I looked up the references, seems good to me. Jimmie. |
Why?
|
Why?
On 27 Mar 2007 16:39:52 -0700, "art" wrote:
On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The take-off angle of a dipole in free space? The angle with respect to what? Walt, W2DU |
Why?
On 31 Mar, 14:36, Walter Maxwell wrote:
On 27 Mar 2007 16:39:52 -0700, "art" wrote: On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The take-off angle of a dipole in free space? The angle with respect to what? Walt, W2DU- Hide quoted text - - Show quoted text - Always zero Walt since it takes two dipoles to tango. |
Why?
Art wrote:
"Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over perfect ground." If possible, look at Terman`s1955 opus page 882: "Effect of Ground on the Directional Pattern of Ungrounded Antennas - Image Antennas." In free space, no reflecting surface is nearby to distort the pattern of a radiator. Terman gives the familiar radiation of a 1/2-wave dipole in space in Fig. 23-4(a) on page 867. Terman says on page 883: "For purposes of calculation, it is convenient to consider that the reflected wave is generated, not by reflection, but rather by an "image" antenna located below the surface of the ground." The summation of the direct and reflected waves from a horoizontal wire above the earth often has serious consequences as Terman notes on page 885: "Consequently, to obtain strong radiation in directions approaching the horizontal using a horizontally polarized radiating system, it is necessary that the height of the antenna above the earth be in the order of one wavelength or more." Terman shows the vertical radiation patterns for a horizontal wire at various heights above the earth in Fig. 23-21 on page 884. Note that half-wave elevation concentrates most energy into a good elevation angle for sky wave reflection at some frequencies and distances. Best regards, Richard Harrison, KB5WZI |
Why?
Art wrote:
"Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over perfect ground." If possible, look at Terman`s1955 opus page 882: "Effect of Ground on the Directional Pattern of Ungrounded Antennas - Image Antennas." In free space, no reflecting surface is nearby to distort the pattern of a radiator. Terman gives the familiar radiation of a 1/2-wave dipole in space in Fig. 23-4(a) on page 867. Terman says on page 883: "For purposes of calculation, it is convenient to consider that the reflected wave is generated, not by reflection, but rather by an "image" antenna located below the surface of the ground." The summation of the direct and reflected waves from a horoizontal wire above the earth often has serious consequences as Terman notes on page 885: "Consequently, to obtain strong radiation in directions approaching the horizontal using a horizontally polarized radiating system, it is necessary that the height of the antenna above the earth be in the order of one wavelength or more." Terman shows the vertical radiation patterns for a horizontal wire at various heights above the earth in Fig. 23-21 on page 884. Note that half-wave elevation concentrates most energy into a good elevation angle for sky wave reflection at some frequencies and distances. Best regards, Richard Harrison, KB5WZI |
Why?
On 1 Apr, 09:34, (Richard Harrison) wrote:
Art wrote: "Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over perfect ground." If possible, look at Terman`s1955 opus page 882: "Effect of Ground on the Directional Pattern of Ungrounded Antennas - Image Antennas." In free space, no reflecting surface is nearby to distort the pattern of a radiator. Terman gives the familiar radiation of a 1/2-wave dipole in space in Fig. 23-4(a) on page 867. Terman says on page 883: "For purposes of calculation, it is convenient to consider that the reflected wave is generated, not by reflection, but rather by an "image" antenna located below the surface of the ground." The summation of the direct and reflected waves from a horoizontal wire above the earth often has serious consequences as Terman notes on page 885: "Consequently, to obtain strong radiation in directions approaching the horizontal using a horizontally polarized radiating system, it is necessary that the height of the antenna above the earth be in the order of one wavelength or more." Terman shows the vertical radiation patterns for a horizontal wire at various heights above the earth in Fig. 23-21 on page 884. Note that half-wave elevation concentrates most energy into a good elevation angle for sky wave reflection at some frequencies and distances. Best regards, Richard Harrison, KB5WZI Very good, all accepted, I am now in a position to ask the real question of "why" where the starting point is acceptable to all. .. I model a dipole in free space to obtain its impedance, this dipole was resonant at right angles to the ground and resting on the ground. I also modelled another dipole over the ground and tipped it over about 5% of its WL but letting the length grow until the dipole was resonant over ground ( ground means perfect ground as per Mininec) I then placed this tipped dipole in free space and noted its impedance. In all cases the impedance in free space was the same though not resonant! In all cases over ground the dipoles were resonant. Why were both dipoles over ground resonant? Why did the program model the dipole at a tipped angle for resonance when given total freedom instead of modeling a dipole at right angles to ground? Regards Art |
Why?
"art" wrote in message oups.com... On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie |
Why?
On 1 Apr, 14:37, "Jimmie D" wrote:
"art" wrote in message oups.com... On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it if you are familiar with the study of waves and fields in electro magnetics.(grin) And there are a couple of people that stand above all others that will possibly provide as to why it is logical. Stand by quietly to listen and learn,you don't have to post if you have nothing to contribute! Read what Richard Harrison has kindly provided and use that as a solid base to think about I have worked very hard to get to this particular point in a thread so as to cut of diversionary talk at the outset. We have an observation, now we need the explanation............Should be a very short thread if we only count contributors with possible explanations as to what has been observed. I'll leave it to others to discern who are the real educated contributors and who are the lemmings. Regards Art |
Why?
On 31 Mar, 14:36, Walter Maxwell wrote:
On 27 Mar 2007 16:39:52 -0700, "art" wrote: On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The take-off angle of a dipole in free space? The angle with respect to what? Walt, W2DU- Hide quoted text - - Show quoted text - Perhaps Walter you are really serious with the above question!!!!!! You have two reference planes, the radiator and the plane of maximum gain(ie. for vertical polarization) Therefor 90 degrees minus the angle between both planes equal "take off angle". Regards Art |
Why?
art wrote:
On 31 Mar, 14:36, Walter Maxwell wrote: On 27 Mar 2007 16:39:52 -0700, "art" wrote: On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The take-off angle of a dipole in free space? The angle with respect to what? Walt, W2DU- Hide quoted text - - Show quoted text - Perhaps Walter you are really serious with the above question!!!!!! You have two reference planes, the radiator and the plane of maximum gain(ie. for vertical polarization) Therefor 90 degrees minus the angle between both planes equal "take off angle". Regards Art Of course he is serious. There are no planes in free space for a dipole. The dipole defines a line, not a plane. Since the pattern of a dipole in free space is a circle viewed from the end, and a cardioid from the side, there is no plane there either. You are plain confused about planes. -- Jim Pennino Remove .spam.sux to reply. |
Why?
art wrote:
On 1 Apr, 14:37, "Jimmie D" wrote: "art" wrote in message snip prior babbling The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it Or, he knows what he is talking about and you are just babbling again. snip remaining babbling nonsense -- Jim Pennino Remove .spam.sux to reply. |
Why?
"art" wrote in message oups.com... On 1 Apr, 14:37, "Jimmie D" wrote: "art" wrote in message oups.com... On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it if you are familiar with the study of waves and fields in electro magnetics.(grin) And there are a couple of people that stand above all others that will possibly provide as to why it is logical. Stand by quietly to listen and learn,you don't have to post if you have nothing to contribute! Read what Richard Harrison has kindly provided and use that as a solid base to think about I have worked very hard to get to this particular point in a thread so as to cut of diversionary talk at the outset. We have an observation, now we need the explanation............Should be a very short thread if we only count contributors with possible explanations as to what has been observed. I'll leave it to others to discern who are the real educated contributors and who are the lemmings. Regards Art Actually my short answers are short because they are to the point if I can find one in your ramblings.The point I made illustated an obvious fault and inconsistencey with your reasoning which you deflect with insults because you have no answers. I know what I had had no value to anyone else but since you were makeing an iirelevant connection between tilt angle of a V antenna and polarization I thought it may give you some pause for thought. Obviously a wasted effort on my part Jimmie |
Why?
On 1 Apr, 16:05, wrote:
art wrote: On 1 Apr, 14:37, "Jimmie D" wrote: "art" wrote in message snip prior babbling The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it Or, he knows what he is talking about and you are just babbling again. snip remaining babbling nonsense -- Jim Pennino Remove .spam.sux to reply. Jim Pennino, it was only a short time ago that you showed your ignorance of electrical laws (gaussian) by calling it nonsense and babling. Now you are attempting to concilidate your position of ignorance, and doing quite well at it I might add. I suggest you accept the same advice I gave Jimmie if you want to avoid being blown away by electric laws once again. Art |
Why?
On 1 Apr, 16:23, "Jimmie D" wrote:
"art" wrote in message oups.com... On 1 Apr, 14:37, "Jimmie D" wrote: "art" wrote in message groups.com... On 27 Mar, 15:12, (Richard Harrison) wrote: Art wrote: "I have his (Kraus`) second edition (Antennas) and I find no mention of radiation from the beginning where current is applied onward." I think I have that edition too. If you review the chapter on "Point Sources" you`ll find: power patterns, a power theorem and its application to isotropic sources, rediation intensity, source with hemispheric power pattern, unidirectional cosine power pattern, etc., etc.. The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a host of others is greatly expanded and improved. It is worth the investment. Being uncertain of what Art really wants, doesn`t stop me from advising him to start by having a look at the famous Sommerfeld formula on page 804 of Terman`s 1955 opus. It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile from a short vertical transmitting antenna given a certain ground conductivity and other conditions. Best regards, Richard Harrison, KB5WZI Richard, I have lots of books but as yet have not found the answer even tho many have posted none appear to really have an answer other than to throw stones. You apparently have found the answer! Could you quote from the books that you are refering to the angle of radiation relative to the radiator, thats it ? If you can't understand that then relay to me the angle of a radiation front relative to a radiator, I'm sure some other people are interested in what you found. Even better, let me know the TOA of a dipole in free space and how much it varies to that of the same dipole over a perfect ground. Use a computor program if you like, anything that sheds light on the matter . The books say that a horizontal "v" antenna should be tipped for max gain, doesn't that raise your interest about the reasoning and mathematics behind this? Jimmie D asked me to state this angle but I have only a expensive computor program that doesn't give the math with the answer. Please read off the angle and the specifics so we all can move on, I don't want a 160 thread postings some thrust upon Walt Art The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it if you are familiar with the study of waves and fields in electro magnetics.(grin) And there are a couple of people that stand above all others that will possibly provide as to why it is logical. Stand by quietly to listen and learn,you don't have to post if you have nothing to contribute! Read what Richard Harrison has kindly provided and use that as a solid base to think about I have worked very hard to get to this particular point in a thread so as to cut of diversionary talk at the outset. We have an observation, now we need the explanation............Should be a very short thread if we only count contributors with possible explanations as to what has been observed. I'll leave it to others to discern who are the real educated contributors and who are the lemmings. Regards Art Actually my short answers are short because they are to the point if I can find one in your ramblings.The point I made illustated an obvious fault and inconsistencey with your reasoning which you deflect with insults because you have no answers. I know what I had had no value to anyone else but since you were makeing an iirelevant connection between tilt angle of a V antenna and polarization I thought it may give you some pause for thought. Obviously a wasted effort on my part Jimmie- Hide quoted text - - Show quoted text - No Jimmie, Richard Harrison gave a very clear starting point to my question which I might add was about an observation about dipoles. The "v" antenna was a subset of the discussion about the possibility of take of angle relative to the plane of antennas generally. None of the above refer to making a salad as you put it. I would point out however that the subject of TOA is a sutle question that relates to both instances but I will leave it up to you to determine that if you wish. On the subject of making a salad that was your statement not mine that you refer to as insulting. Cool down for a while and then step back in Art |
Why?
art wrote:
On 1 Apr, 16:05, wrote: art wrote: On 1 Apr, 14:37, "Jimmie D" wrote: "art" wrote in message snip prior babbling The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it Or, he knows what he is talking about and you are just babbling again. snip remaining babbling nonsense -- Jim Pennino Remove .spam.sux to reply. Jim Pennino, it was only a short time ago that you showed your ignorance of electrical laws (gaussian) by calling it nonsense and babling. Now you are attempting to concilidate your position of ignorance, and doing quite well at it I might add. I suggest you accept the same advice I gave Jimmie if you want to avoid being blown away by electric laws once again. Art Like all your other posts, this one makes no sense either. As I understand it, you want to blow me? -- Jim Pennino Remove .spam.sux to reply. |
Why?
On 1 Apr, 17:35, wrote:
art wrote: On 1 Apr, 16:05, wrote: art wrote: On 1 Apr, 14:37, "Jimmie D" wrote: "art" wrote in message snip prior babbling The V antenna is a terminated traveling wave antenna the dipoles that you have been refering to are standingwave antennas. You are comparing apples and oranges. The best I can tell is that all other references you made to tilt have been perpedicular to the direction of the wave front. The V antenna is tilted in the direction of the wave front, more apples and oranges. Throw in some grapes and pineapple and we will have fruit salad. Jimmie- Hide quoted text - - Show quoted text - Jimmie, You are way to quick with your answers which means you are not commited to follow thru in serious thinking. There is a perfectly logical reason for it Or, he knows what he is talking about and you are just babbling again. snip remaining babbling nonsense -- Jim Pennino Remove .spam.sux to reply. Jim Pennino, it was only a short time ago that you showed your ignorance of electrical laws (gaussian) by calling it nonsense and babling. Now you are attempting to concilidate your position of ignorance, and doing quite well at it I might add. I suggest you accept the same advice I gave Jimmie if you want to avoid being blown away by electric laws once again. Art Like all your other posts, this one makes no sense either. As I understand it, you want to blow me? -- Jim Pennino Remove .spam.sux to reply.- Hide quoted text - - Show quoted text - Wow, I didn't know you lived near San Francisco. Your pattern of life is certainly different to that of the Mid West. I suppose if you must live near your "friemds" then you must go where the action your looking for is at. Hopefully you live at a long distance from schools and your computor is scanned regularly by the authorities.I had suspected from your postings that you were not "normal" as well as being uneducated. I am going to plonk your posts as I don't wish to be associated with you in any way especially that kind of talk. You make me shiver.... YUK |
Why?
art wrote:
Nothing but babble as usual. -- Jim Pennino Remove .spam.sux to reply. |
| All times are GMT +1. The time now is 12:58 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com