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#1
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I am getting ready to put up my masts (5 of them) for a 160m
full wave loop. For the most part I am using recycled telescoping tv masts which will be up around 50+ feet. The masts are metal. There will be a pulley at the top of the mast and the antenna will be pulled up with a dacron rope. The question is what material to use for the guy wires on the masts. Is there a compelling argument not to use wire guys because they might be of lengths that will resonate or otherwise detract from the anticipated effectiveness of this antenna, or is this a non issue, given that the mast is already metal anyway, and the rope to the insulator holding up the antenna wire (#14 hard drawn braided copper) will be approximately 10 feet away from the top of the mast. Wire for the guys (three sets of four wires, eg. one set for each of the top three tiers) would be easier, and somewhat more permanent than rope. If I were to use the dacron rope for the guys, then I would put up pulleys (that is 12 pulleys just on one mast) so that a new rope could be threaded up there in the future without the mast coming down. For all practical purposes wire guys would be permanent. If wire is used is it necessary to break up the lengths of the guys with dielectric strain insulators or is this a non-issue with this antenna design. The physical loop circumscribed by the actual circumstances of mast placement is approx. 588 feet. The loop needs to be about 540 feet, this difference of 48' will be absorbed by the 5 dacron ropes pulling up the antenna, that is why I am saying the antenna wire will be about 10' away from the tops of the masts. It is anticipated that the antenna will be fed by diy ladder line from one of the corners. Any pointers or useful information is welcome. tnx, -bill |
#2
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On Sat, 17 Apr 2004 18:14:58 GMT, zeno wrote:
I am getting ready to put up my masts (5 of them) for a 160m full wave loop. For the most part I am using recycled telescoping tv masts which will be up around 50+ feet. Hi Bill, You are on the threshold of being able to do much more for slightly more effort. Let's suppose you use wire with insulators to break them up (generally only advised as a must below tower mounted beams so that opportunistic resonances don't mess up directionality and tune). Further, let's suppose all wires at the top have a good metal connection to the mast. Further, let's suppose each of these wires is broken such that the first insulator(s) is more than 25 or 30 feet above ground (straight down, I am not measuring along the wire). Nothing else matters beyond what you would then do for general construction. I presume that all masts are driven into the ground (or at least are not insulated from ground); and that at each mast you could build a radial ground screen of eight to a dozen wires as broad as those first set of insulators are out from the mast (probably 20 to 30 feet each). You then have the opportunity of developing four broadband vertical antennas (each with a gamma feed because of the grounded situation). There's a good chance they would operate on 80M without too much effort (you might push them to 160). Most of the work is in the top connection, and the first set of insulators - beyond that no commitments are needed if you simply decide to walk away later. That is easy with little difference in the up front effort. 73's Richard Clark, KB7QHC |
#3
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Richard,
Interesting, even if a bit above my current point in the learning curve. Generally, I am experimenting with antennas here, trying to find the junction between theoreticl concepts, and the physical realities of the real estate, building, and trees, etc. just all hams do, I am sure. Antenna #1 is now up, it is an OCF stung between to trees, not bad. But now I am moving on to #2 which is this proposed 160m full wave loop. I have collected a handful of these old masts (junk yards, the local dump etc.) nice material to have on hand. Here is more detail of the proposed loop, so that I can better glean something constructive from your intriguing ideas. Only one of the proposed masts will be resting on the ground out in the middle of the orchard. Three are attached to buildings (adding height) and one is attached to a sturdy wooden "telephone" pole (again adding height and a way of mounting). The idea of putting radials in the ground does not seem practical for most of these masts, however, your idea is intriguing none the less. Since I have a bunch of masts to play with, and I am in the antenna experimental mode, and have rural real estate to play around in, I am wondering about the antenna you have suggested. Maybe we are talking about the possibility of Antenna #3 here. Am I to understand that a promising antenna (you call a broadband vertical) can be made from a single 50 foot telescoping tv metal mast, the base of which is at ground level, utililizing the guy wires as part of the antenna system, with a system of radials in the ground underneath? How would I best feed this antenna, and would it be worthwhile with just this single mast, and what advantages would such an antenna have over others that I might construct? At this point, I have only made plans for various wire antennas. Do not have any verticals. The tower and beam are only a twinkle in my minds eye, and I have to visit that neighbor who has a 75 footer he is not using that he suggested might be for sale, but that is down the line a way. Meanwhile I am tree fishing here, and recycling masts when I can find them. I have more or less concluded, that my nicest 50 foot telescoping tv mast, is not the way to go for a "beam" and rotator, even the small ones, the engineering of such a project seems to court a Laurel and Hardy kind of fiasco in my imagination, at least until someone tells me that they did it and it was smooth sailing..... which is to say, I do not yet have a plan for some kind of antenna which can be rotated....whatever its desing might be..... man, there is so much to this antenna thing......it is what this is all about.....and I love it.... -bill Richard Clark wrote: On Sat, 17 Apr 2004 18:14:58 GMT, zeno wrote: I am getting ready to put up my masts (5 of them) for a 160m full wave loop. For the most part I am using recycled telescoping tv masts which will be up around 50+ feet. Hi Bill, You are on the threshold of being able to do much more for slightly more effort. Let's suppose you use wire with insulators to break them up (generally only advised as a must below tower mounted beams so that opportunistic resonances don't mess up directionality and tune). Further, let's suppose all wires at the top have a good metal connection to the mast. Further, let's suppose each of these wires is broken such that the first insulator(s) is more than 25 or 30 feet above ground (straight down, I am not measuring along the wire). Nothing else matters beyond what you would then do for general construction. I presume that all masts are driven into the ground (or at least are not insulated from ground); and that at each mast you could build a radial ground screen of eight to a dozen wires as broad as those first set of insulators are out from the mast (probably 20 to 30 feet each). You then have the opportunity of developing four broadband vertical antennas (each with a gamma feed because of the grounded situation). There's a good chance they would operate on 80M without too much effort (you might push them to 160). Most of the work is in the top connection, and the first set of insulators - beyond that no commitments are needed if you simply decide to walk away later. That is easy with little difference in the up front effort. 73's Richard Clark, KB7QHC |
#4
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On Sat, 17 Apr 2004 19:16:52 GMT, zeno wrote:
Am I to understand that a promising antenna (you call a broadband vertical) can be made from a single 50 foot telescoping tv metal mast, the base of which is at ground level, utililizing the guy wires as part of the antenna system, with a system of radials in the ground underneath? How would I best feed this antenna, and would it be worthwhile with just this single mast, and what advantages would such an antenna have over others that I might construct? Hi Bill, We will do this by stages. We are going to maximize what you already have: mast material. Grounded or ungrounded are immaterial - there are ways of getting RF into either. If grounded, this may require a drop wire described below (I was a little too enthusiastic about possibilities in the first post). The masts will be guyed. The trick here is to think in advance to be able to support ANY mission, vertical OR horizontal antennas. BOTH may be available at the same time. The usual vertical of 50 feet may resonate at several places in HF, but almost certainly not in the Ham bands - so we must expect some form of matching along the way. For ungrounded masts this can be done within a meter of ground so there is no going aloft to perform any jobs. For grounded masts you may wish to have a conductive yard arm, perhaps more accurately described not as a yard but as 18 inches, dropping a wire to ground for a 160M or 80M Gamma feed, or as a folded monopole. Note, I suggest 160M or 80M operation for an obviously too short vertical. This is where the guy wires come in handy. As described previously, think of them as the skeleton of an umbrella (no fabric, but ribs expanded out). With the use of insulators, this can be achieved so that you can construct what is called a "capacitive top hat." Such additions to verticals lower their resonance (but this does not imply it makes them 50Ohms - that is a separate issue). You want them to be resonant (so they will absorb and radiate power), but you will need to match them further (no different that any wire antenna for that matter). For 80M, this antenna will probably offer 20 to 30 Ohms (not bad, but not 50). For 160M, this antenna could offer 5 to 20 Ohms (becoming difficult, but not undo-able), but in all likelihood, it will also have reactance (the top hat will probably not be big enough). Now, why would you want another 160M antenna? The bad news is that horizontals in this band are abysmal performers even if you could get one up the minimum quarter wave (a long way from only 50 feet up). Verticals on the other hand use earth far more effectively for communication in this band (how many AM stations do you know of with horizontal antennas?). 80M sits on the borderline of earth characteristics where horizontals may do better, but this doesn't mean that verticals do poorer. Higher bands see earth differently, and verticals need height (lifted into the air) to compete; or they need to reside near a lake or the sea. However, most of this discussion gets very far afield. The point is to plan ahead, construct top hats (they will mix easily with your loop project) and think about the gamma drop wires if the masts are grounded. This is very little investment and you have four opportunities (this then brings experimentation with phased, vertical arrays - each mast driven separately through delay lines). 73's Richard Clark, KB7QHC |
#5
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Richard,
tnx a bunch for this fb. I am going to digest it a bit while I go out and mow the weeds around the prospective antenna mast sites (in my usual effort to convert manual labor into my preferred fantasies). I do see your important point about anticipating future possibilites before these beasts are already committed in the air, I like that approach. You have also inspired me to re-examine some of those carelessly glossed over chapters in the various Antenna books here at the shack. We will undoubtedly need to continue this qso a bit more for me to fully apply your ideas to the particularities here. So, to understand something basic: What you are talking about is not necessarily interferring in any way with the 160m loop project, but rather to anticipate additional antenna experiments utilizing the poles (masts). If the vertical antenna ideas are later explored, would each mast be a separate antenna requiring its own coax feed line? btw, my newbie's facination with the ladder line fed 160 loop has to do with its multi-band promise. To tell the truth, I have heard very little on 160m here. Seems like (at least with the new 80m OCF (up 30' ++ depending on which end) I am hearing alot on 20, 40, and 80 with this old Knwd 530. Sure beats the old tube Hallicrafters I was using only a few months ago when I started my process of catching up with 50 years inactivity....! I might end up one of those hams that loves the old tube gear, but also uses the latest technology as well.....those fancy Icoms are kind of tempting....but what do I know.... bill Richard Clark wrote: On Sat, 17 Apr 2004 19:16:52 GMT, zeno wrote: Am I to understand that a promising antenna (you call a broadband vertical) can be made from a single 50 foot telescoping tv metal mast, the base of which is at ground level, utililizing the guy wires as part of the antenna system, with a system of radials in the ground underneath? How would I best feed this antenna, and would it be worthwhile with just this single mast, and what advantages would such an antenna have over others that I might construct? Hi Bill, We will do this by stages. We are going to maximize what you already have: mast material. Grounded or ungrounded are immaterial - there are ways of getting RF into either. If grounded, this may require a drop wire described below (I was a little too enthusiastic about possibilities in the first post). The masts will be guyed. The trick here is to think in advance to be able to support ANY mission, vertical OR horizontal antennas. BOTH may be available at the same time. The usual vertical of 50 feet may resonate at several places in HF, but almost certainly not in the Ham bands - so we must expect some form of matching along the way. For ungrounded masts this can be done within a meter of ground so there is no going aloft to perform any jobs. For grounded masts you may wish to have a conductive yard arm, perhaps more accurately described not as a yard but as 18 inches, dropping a wire to ground for a 160M or 80M Gamma feed, or as a folded monopole. Note, I suggest 160M or 80M operation for an obviously too short vertical. This is where the guy wires come in handy. As described previously, think of them as the skeleton of an umbrella (no fabric, but ribs expanded out). With the use of insulators, this can be achieved so that you can construct what is called a "capacitive top hat." Such additions to verticals lower their resonance (but this does not imply it makes them 50Ohms - that is a separate issue). You want them to be resonant (so they will absorb and radiate power), but you will need to match them further (no different that any wire antenna for that matter). For 80M, this antenna will probably offer 20 to 30 Ohms (not bad, but not 50). For 160M, this antenna could offer 5 to 20 Ohms (becoming difficult, but not undo-able), but in all likelihood, it will also have reactance (the top hat will probably not be big enough). Now, why would you want another 160M antenna? The bad news is that horizontals in this band are abysmal performers even if you could get one up the minimum quarter wave (a long way from only 50 feet up). Verticals on the other hand use earth far more effectively for communication in this band (how many AM stations do you know of with horizontal antennas?). 80M sits on the borderline of earth characteristics where horizontals may do better, but this doesn't mean that verticals do poorer. Higher bands see earth differently, and verticals need height (lifted into the air) to compete; or they need to reside near a lake or the sea. However, most of this discussion gets very far afield. The point is to plan ahead, construct top hats (they will mix easily with your loop project) and think about the gamma drop wires if the masts are grounded. This is very little investment and you have four opportunities (this then brings experimentation with phased, vertical arrays - each mast driven separately through delay lines). 73's Richard Clark, KB7QHC |
#6
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On Sat, 17 Apr 2004 20:46:06 GMT, zeno wrote:
We will undoubtedly need to continue this qso a bit more for me to fully apply your ideas to the particularities here. Hi Bill, That's the whole point of this group. So, to understand something basic: What you are talking about is not necessarily interferring in any way with the 160m loop project, but rather to anticipate additional antenna experiments utilizing the poles (masts). Exactimundo. If the vertical antenna ideas are later explored, would each mast be a separate antenna requiring its own coax feed line? Yup - any, all, or none depending upon where the future leads. 73's Richard Clark, KB7QHC |
#7
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Hi Richard,
I think at least one of the metal masts I will be using to hang the 160m loop might lend itself to the vertical antenna you suggest. It is the one that is a full 50' in height, and will be out in the middle of the orchard where ground radials can be installed easily. Unfortunately this particular mast is the one farthest away from the shack, approx. 500 feet. Questions: 1. For reference purposes, what is the exact description (name) of this vertical? Any recommendations for information in print about this concept? 2. What band, or bands, would it be good for? (Assuming the guy wires are generally in the position of effectivenes as guy wires.) 3. Would it be monoband, tuned to an exact f, or possibly multiband? 4. Where would one attach the feed line and would a run of 500' to the shack still be worth the effort? 5. If I understand, the antenna is comprised of the mast itself (with telescoping sections securely and electrically bonded to each other) plus the "extension" of calculated lengths of the four guy wires, utilizing insulators at precise points before being attached to ground anchors. 6. How would the mast be mounted to the ground? Should it ideally be isolated from ground or contiguous with the ground? Theortically I could build a short wooden platform or something. 7. Other than the mast itself, the four guy wires, and some kind of system of radials in the ground, are there any other elements to this antenna that I should know about or be thinking about? Bill Richard Clark wrote: On Sat, 17 Apr 2004 18:14:58 GMT, zeno wrote: I am getting ready to put up my masts (5 of them) for a 160m full wave loop. For the most part I am using recycled telescoping tv masts which will be up around 50+ feet. Hi Bill, You are on the threshold of being able to do much more for slightly more effort. Let's suppose you use wire with insulators to break them up (generally only advised as a must below tower mounted beams so that opportunistic resonances don't mess up directionality and tune). Further, let's suppose all wires at the top have a good metal connection to the mast. Further, let's suppose each of these wires is broken such that the first insulator(s) is more than 25 or 30 feet above ground (straight down, I am not measuring along the wire). Nothing else matters beyond what you would then do for general construction. I presume that all masts are driven into the ground (or at least are not insulated from ground); and that at each mast you could build a radial ground screen of eight to a dozen wires as broad as those first set of insulators are out from the mast (probably 20 to 30 feet each). You then have the opportunity of developing four broadband vertical antennas (each with a gamma feed because of the grounded situation). There's a good chance they would operate on 80M without too much effort (you might push them to 160). Most of the work is in the top connection, and the first set of insulators - beyond that no commitments are needed if you simply decide to walk away later. That is easy with little difference in the up front effort. 73's Richard Clark, KB7QHC |
#8
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Richard,
I just remembered, there will be three tiers of guy wires (four wires at each level), one set at the top, one set ten feet down from that, another ten feet down from that,etc.. Can all of these guy wires be part of the antenna system? Like you mentioned, kind of a "umbrella skeleton". It might be tricky to make sure that the guy wires both bond to the circular ring around the mast which the wires attach to, and to make sure that this metal ring also bonds well to the mast, I will have to think about a good technique here. I guess I could carefully weld them in place (normally they are tightly fitted to the pole, but can still slide up or down), I am sure you have seen these old tv telescoping masts, they seem fairly standard. Bill zeno wrote: Hi Richard, I think at least one of the metal masts I will be using to hang the 160m loop might lend itself to the vertical antenna you suggest. It is the one that is a full 50' in height, and will be out in the middle of the orchard where ground radials can be installed easily. Unfortunately this particular mast is the one farthest away from the shack, approx. 500 feet. Questions: 1. For reference purposes, what is the exact description (name) of this vertical? Any recommendations for information in print about this concept? 2. What band, or bands, would it be good for? (Assuming the guy wires are generally in the position of effectivenes as guy wires.) 3. Would it be monoband, tuned to an exact f, or possibly multiband? 4. Where would one attach the feed line and would a run of 500' to the shack still be worth the effort? 5. If I understand, the antenna is comprised of the mast itself (with telescoping sections securely and electrically bonded to each other) plus the "extension" of calculated lengths of the four guy wires, utilizing insulators at precise points before being attached to ground anchors. 6. How would the mast be mounted to the ground? Should it ideally be isolated from ground or contiguous with the ground? Theortically I could build a short wooden platform or something. 7. Other than the mast itself, the four guy wires, and some kind of system of radials in the ground, are there any other elements to this antenna that I should know about or be thinking about? Bill Richard Clark wrote: On Sat, 17 Apr 2004 18:14:58 GMT, zeno wrote: I am getting ready to put up my masts (5 of them) for a 160m full wave loop. For the most part I am using recycled telescoping tv masts which will be up around 50+ feet. Hi Bill, You are on the threshold of being able to do much more for slightly more effort. Let's suppose you use wire with insulators to break them up (generally only advised as a must below tower mounted beams so that opportunistic resonances don't mess up directionality and tune). Further, let's suppose all wires at the top have a good metal connection to the mast. Further, let's suppose each of these wires is broken such that the first insulator(s) is more than 25 or 30 feet above ground (straight down, I am not measuring along the wire). Nothing else matters beyond what you would then do for general construction. I presume that all masts are driven into the ground (or at least are not insulated from ground); and that at each mast you could build a radial ground screen of eight to a dozen wires as broad as those first set of insulators are out from the mast (probably 20 to 30 feet each). You then have the opportunity of developing four broadband vertical antennas (each with a gamma feed because of the grounded situation). There's a good chance they would operate on 80M without too much effort (you might push them to 160). Most of the work is in the top connection, and the first set of insulators - beyond that no commitments are needed if you simply decide to walk away later. That is easy with little difference in the up front effort. 73's Richard Clark, KB7QHC |
#9
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On Sun, 18 Apr 2004 18:10:13 GMT, zeno wrote:
Hi Richard, I think at least one of the metal masts I will be using to hang the 160m loop might lend itself to the vertical antenna you suggest. Hoist wire for the rest! After all, you are already doing that aren't you? It is the one that is a full 50' in height, and will be out in the middle of the orchard where ground radials can be installed easily. Unfortunately this particular mast is the one farthest away from the shack, approx. 500 feet. Questions: 1. For reference purposes, what is the exact description (name) of this vertical? Any recommendations for information in print about this concept? Folded Unipole (N. O. L.); Type UG; NORD; Triangular Folded Unipole (VOA aboard the USCGC Courier) "The Amateur Radio Vertical Antenna Handbook," Capt. Paul H. Lee, N6PL 2. What band, or bands, would it be good for? (Assuming the guy wires are generally in the position of effectivenes as guy wires.) Folded Triangular Unipole is 45 feet tall and rated from 3 to 10.5 MHz NORD 30 feet tall and rated from 2 to 4 MHz; Folded NOL Unipole is 0.124 wavelength tall; Type UG is 0.048 wavelength tall. 3. Would it be monoband, tuned to an exact f, or possibly multiband? Depends on antenna type and number of guy wires. The devil is in the details as the saying goes. 4. Where would one attach the feed line and would a run of 500' to the shack still be worth the effort? At the base. Run an exciter to a remote amp. That is, put your loss into the cheapest signal to boost. Move the shack ;-) 5. If I understand, the antenna is comprised of the mast itself (with telescoping sections securely and electrically bonded to each other) plus the "extension" of calculated lengths of the four guy wires, utilizing insulators at precise points before being attached to ground anchors. Exactimundo. 6. How would the mast be mounted to the ground? Should it ideally be isolated from ground or contiguous with the ground? Theortically I could build a short wooden platform or something. Folded Unipoles (which are wide band within the band of interest and some bands are very wide) are fed with their base at ground potential (add radials here). The feed point is through a cap, up the drop wire. that is descending from the conductive (half) yard arm. The other types are fed in series (the base insulated from ground). Comparisons should be studied. If building an insulated base is no problem, shorting it to ground becomes an easy option. 7. Other than the mast itself, the four guy wires, and some kind of system of radials in the ground, are there any other elements to this antenna that I should know about or be thinking about? Don't forget the drop wire. Search the web for Folded Unipoles (verticals) for illustrations to make this clearer. There is also a series cap to tune it. It is basically a very big gamma match. By varying the diameter of the drop wire to the mast diameter, you get transformer action that boosts or lowers the feedpoint R. As most of these are very short antennas with very low radiation resistance, the wire diameter to mast diameter ratio often boosts that value to 50 Ohms without too much problem. WARNING, this boost does not raise efficiency! That remains a function of the radiation resistance compared to structure Ohmic loss and ground loss. The feed point R is simply a boosting of BOTH the radiation resistance AND those loss Rs too. 73's Richard Clark, KB7QHC |
#10
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![]() Richard Clark wrote: On Sun, 18 Apr 2004 18:10:13 GMT, zeno wrote: Hi Richard, I think at least one of the metal masts I will be using to hang the 160m loop might lend itself to the vertical antenna you suggest. Hoist wire for the rest! After all, you are already doing that aren't you? This goes back to my original question, should I use rope or wire for the guys on these masts. If I use the dacron rope I would use pulleys so i can later change out the rope if need be without taking down the masts. My concern with using wire as guys (as was usually done with old tv masts on roofs) was that all these lengths of wire in the proximity might in some way adversely effect my 160m loop. Using wire guys would be easier. Aside from all this additional complication of anticipating some kind of future vertical antenna system I barely understand at this point, is it definitely ok to use wire as guys? I might just use wire guys, not broken up with insulators, not worrying about these future antenna possibilities. These masts are simply too far away from the shack, but I need to guy them just to put them up. When using metal masts for wire antennas, what is the standard practice for guying these masts? Folded Unipole (N. O. L.); Type UG; NORD; Triangular Folded Unipole (VOA aboard the USCGC Courier) "The Amateur Radio Vertical Antenna Handbook," Capt. Paul H. Lee, N6PL 2. What band, or bands, would it be good for? (Assuming the guy wires are generally in the position of effectivenes as guy wires.) Folded Triangular Unipole is 45 feet tall and rated from 3 to 10.5 MHz NORD 30 feet tall and rated from 2 to 4 MHz; Folded NOL Unipole is 0.124 wavelength tall; Type UG is 0.048 wavelength tall. I will not really understand this antenna until I can see a simple picture of it somewhere, and, since I am a beginner, would need to know what purposes such an antenna might serve me at this point, eg. is there a particular band or a particular advantage that I cannot get elsewhere with my other more common antenna systems. I am at a point where I am simply looking for possible worthwhile antennas I can construct hoping that one or two might prove effective. You did mention something about the advantages of vertical over horizontal and I was not sure which band you were referring to. At this point I have not considered any vertical antennas, but am open to verticals, if not the folded unipole you are discussing, maybe some other kind of vertical. At this point I don't know anything about verticals really other than the hassel of putting in radials. I like the idea of a mast being an antenna and the guy wires being part of the antenna, but what I need is a child's picture book illustration of such an antenna and why such an antenna would be the bees knees for me. Here is what I currently (and practically) understand about the antenna you are discussing. It is a vertical folded dipole of some kind in which the 50' mast is one leg, another drop wire from the top is the other half (which I assume is fed somewhere in the middle of this drop wire by hooking up coax feed line). In addition to this folded dipole (vertically oriented) and with one leg (the mast) much greater diamter than the other half (drop wire), it has a bunch of guy wires attached to the mast at various points which somehow add something to the antenna, the guy wires need to be some special length. There needs to be an elaborate radial system underneath threaded through the orchard with weeds growing on top of them and not shallow enough to get caught in the mower. To even use this antenna, on whatever mysterious band it is good for, I would have to make special electronic accomodations to deal with the loss resulting from the feedline being greater than 500 feet to the shack (or move the shack closer to the antenna), eventually this long feedline would have to be in conduit and buried. I think that it would be easier just to put up another mast, closer to the shack, just for the purpose of exploring this antenna, rather than bend over backwards to make use of a mast out in the field just because it is there. These old telescoping tv masts are plentiful at the county dump, I will keep collecting them. It is conceivable I could put one up with a feedline less than 200 feet to the shack, that shouldn't be any problem with loss, no? But I still need to know, or be reminded, in the simplest of terms, why I want such an antenna, and what special advantages it might have on what bands I might eventually be excited about. |
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