Re: Topband: Elevated Radials EPILOGUE
ON4UN's series of books have always had way too many individual assumptions and we all know what happens then. Those books offer a place to start and then apply your own unique soil and local conditions and change as needed. Carl KM1H - Original Message - From: "Buck wh7dx" To: Sent: Wednesday, March 06, 2013 3:42 PM Subject: Re: Topband: Elevated Radials EPILOGUE There is some good stuff in ON4UN Low Band Book - Chapter 9-10 on Elevated Radials. He suggests that an elevated system would be even better above ground versus on the ground in poor conditions. References 0.1 wave height or less. For 160m that could be 50 feet down. In Section 2.2.7 K3LC says that there is no point in raising radials any higher than 6 meters on 160 or 3 meters on 80 meters. Such a height would be between 0.2db of what can be achieved with 64 buried radials... N7CL says they need to be higher The perfect on ground system might be 50-100 1/4 wave ground radials... In 2.1.2 he warns of trusting modeling because of outside factors. 9-12 Figure 9-18 (modeling) regarding 160m gain using 1/4 wave is interesting over average ground. If you wanted max. it suggests using 120 - 80meter radials. But the difference between 120 (1.5 dbi gain) and going with 32 (1.0 dbi gain) would make one wonder if it was really worth it for another 1-2 miles of wire.. work? 0.5 dbi gain? The Conclusion in 9-14 is interesting.. basically saying.. "Take the example of an 80-meter vertical over average ground: going from a lousy eight 20-meter long radials to 120 radials would only buy you 1.4db of gain, which is less than what I think it is in reality. In very good ground that difference wold be only 0.7 db!" 2.1.3.2 - "From these almost 70-year old studies, we can conclude that 60 quarter-wave long radials is a cost effective optimal solution for amateur purposes. K3NA's work in 2.3.1.3 talks about using 1/16 wave radials.. not going beyond 48.. but that doesn't match up with N6BV's work several years prior. In 2.2 Elevated Radial and beyond it's gets really interesting and less conclusive? The Conclusion States - "If you want to play it extra safe, and if you have the tower height, get the radials up as high as possible and add a few more. Use a ground screen if you have it. "It all is very logical. Get away from the lossy ground or hide the lossy ground with a dense screen using many radials. No free lunch!". This was one book and it goes on. All of this sounds like a great episode for Ham Radio Myth Busters... 73, Bryan WH7DX [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Mr. & Mrs. B and is intended for use only by the individual or entity to which it is addressed, or where ever the hell it ends up, and will almost certainly contain information that will offend a large portion of the population, which isn't our concern. If you are not the intended lucky recipient, or it appears that this mail has been forwarded to you without the proper authority of the Wizard of Email or Al Gore, you are notified that any thought, use, or consumption of this email is entirely your choice. In such case, Bon AppetitNote: A $.02 Internet Tax was charged for receiving this email and all funds were given to some family somewhere in America or the U.N Have a nice day. _ Topband Reflector - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1430 / Virus Database: 2641/5652 - Release Date: 03/06/13 _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
Now in the most recent 22nd Edition of the ARRL Antenna Book... 3-14 - It goes on to say that a few elevated radials should perform as well as a large number of ground radials And that the signal will improve quickly with just a little elevation... Interesting graph - Figure 3.27 - you need to get to about 30 ground radials to equal 4 elevated. The elevated needed to be symmetric... It goes on from there. I suspect the fairly recent (??) information on the advantages of elevated has let to at least one military study and a ton of other information on the internet... talk about reconditioned AM stations with elevated radial? Buried is safer - but it requires a lot more work and money. But if you can use 8 (???) elevated radials versus 60 buried on 160M we're talking a mile difference in wire. Don't get me wrong, I'm new to this and by no means knowledgeable in the field - but I can say that after reading these two very well know books.. and a ton of stuff on the Internet - which is my specialty.. It's a little confusing.. It's time for Myth Busters Ham Radio. It should be fairly simple I would think.. Poor ground - (X) number of elevated at a specified wave length height - symmetrically laid out... Decent ground - (X) ground or (X) elevated at this wave length height.. etc That should do it for me. If anyone has more "real life" info on this.. email me at my call sign + @hawaii.rr.com 73 Bryan WH7DX [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Mr. & Mrs. B and is intended for use only by the individual or entity to which it is addressed, or where ever the hell it ends up, and will almost certainly contain information that will offend a large portion of the population, which isn't our concern. If you are not the intended lucky recipient, or it appears that this mail has been forwarded to you without the proper authority of the Wizard of Email or Al Gore, you are notified that any thought, use, or consumption of this email is entirely your choice. In such case, Bon AppetitNote: A $.02 Internet Tax was charged for receiving this email and all funds were given to some family somewhere in America or the U.N Have a nice day. _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
There is some good stuff in ON4UN Low Band Book - Chapter 9-10 on Elevated Radials. He suggests that an elevated system would be even better above ground versus on the ground in poor conditions. References 0.1 wave height or less. For 160m that could be 50 feet down. In Section 2.2.7 K3LC says that there is no point in raising radials any higher than 6 meters on 160 or 3 meters on 80 meters. Such a height would be between 0.2db of what can be achieved with 64 buried radials... N7CL says they need to be higher The perfect on ground system might be 50-100 1/4 wave ground radials... In 2.1.2 he warns of trusting modeling because of outside factors. 9-12 Figure 9-18 (modeling) regarding 160m gain using 1/4 wave is interesting over average ground. If you wanted max. it suggests using 120 - 80meter radials. But the difference between 120 (1.5 dbi gain) and going with 32 (1.0 dbi gain) would make one wonder if it was really worth it for another 1-2 miles of wire.. work? 0.5 dbi gain? The Conclusion in 9-14 is interesting.. basically saying.. "Take the example of an 80-meter vertical over average ground: going from a lousy eight 20-meter long radials to 120 radials would only buy you 1.4db of gain, which is less than what I think it is in reality. In very good ground that difference wold be only 0.7 db!" 2.1.3.2 - "From these almost 70-year old studies, we can conclude that 60 quarter-wave long radials is a cost effective optimal solution for amateur purposes. K3NA's work in 2.3.1.3 talks about using 1/16 wave radials.. not going beyond 48.. but that doesn't match up with N6BV's work several years prior. In 2.2 Elevated Radial and beyond it's gets really interesting and less conclusive? The Conclusion States - "If you want to play it extra safe, and if you have the tower height, get the radials up as high as possible and add a few more. Use a ground screen if you have it. "It all is very logical. Get away from the lossy ground or hide the lossy ground with a dense screen using many radials. No free lunch!". This was one book and it goes on. All of this sounds like a great episode for Ham Radio Myth Busters... 73, Bryan WH7DX [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Mr. & Mrs. B and is intended for use only by the individual or entity to which it is addressed, or where ever the hell it ends up, and will almost certainly contain information that will offend a large portion of the population, which isn't our concern. If you are not the intended lucky recipient, or it appears that this mail has been forwarded to you without the proper authority of the Wizard of Email or Al Gore, you are notified that any thought, use, or consumption of this email is entirely your choice. In such case, Bon AppetitNote: A $.02 Internet Tax was charged for receiving this email and all funds were given to some family somewhere in America or the U.N Have a nice day. _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
1) If you have the space and work hours and money isn't an issue - go with 120 1/4 wave buried radials. That is a myth that stems from the FCC not requiring a ground system proof of performance when more than ~110 radials are used, and 120 radials is pretty much a waste of time for hams. At my location on 40 meters, somewhere about 15 radials got on the flat part of efficiency curve and on 160 about 30-40 radials gets really flat for changes. The only reason I have 100 radials on my 200 ft tower is I had the wire, I have a radial plow, I wanted lightning protection, and I used to hang horizontal antennas in that area so I wanted a counterpoise under them. 2) Good soil doesn't require as many radials.. someone was commenting on the AM towers be reconditioned - using elevated radials. That isn't a good rule. There are two cases of zero loss, perfect conductivity and no conductivity at all. Someplace between the two, loss will peak. I have a mixture of soil from swampy rich soil to red clay. My 40 meter vertical test was over a patch of red rocky clay, and it only needed ~15 radials to get on the flat part of the curve. 3) Elevated radials work better with poor ground conditions. Higher with lower bands.. 15-25ft on 160m.. That's not a good rule, or at least it is not a rule that has been substantiated. 4) You don't need as many elevated radials as ground radial.. (debate about 4 to 12 or so?) I'd say 12 but would like to see a study. Some say 2 or 4? Some, like N6LF, say 16 to be safe. Once you have the control antenna it's easy to start comparing real world results.How's 12 radials sound?Cut 4 off.. how's 8 sounds. The K.I.S.S. approach. I don't think it would be very hard to disconnect some radials and say - "how's the signal now?"... two guys with a walkie talkie making doing some tests cutting some wires etc... You would have to actually remove the radials to see the full effect. The best way is to start with empty soil and work upwards, not cut things. An A-B test comparison to a stable reference would be simple and reliable. 73 Tom _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
I'd like to read whatever information (real results) you guys have on this. My email is my call sign with @hawaii.rr.com Thank you Milt for your info. Nice setup!If I understood it correctly - the buried and elevated were comparable. I've read most of the well known books on this and it's not conclusive.. after all these years - I would expect it be more certain. I don't think the data is getting out there perhaps or I haven't seen it.A study done working with low band grounding etc... Things like 1) If you have the space and work hours and money isn't an issue - go with 120 1/4 wave buried radials. 2) Good soil doesn't require as many radials.. someone was commenting on the AM towers be reconditioned - using elevated radials. 3) Elevated radials work better with poor ground conditions. Higher with lower bands.. 15-25ft on 160m.. 4) You don't need as many elevated radials as ground radial.. (debate about 4 to 12 or so?) I'd say 12 but would like to see a study. Some say 2 or 4? Once you have the control antenna it's easy to start comparing real world results.How's 12 radials sound?Cut 4 off.. how's 8 sounds. The K.I.S.S. approach. I don't think it would be very hard to disconnect some radials and say - "how's the signal now?"... two guys with a walkie talkie making doing some tests cutting some wires etc... During the 160M SSB there was a guy in CA who was 59 the whole time into Hawaii. I called him back on the last day and asked what he was using.. I forgot what he said, but he switched his antennas and he went from a solid S9 to S5. He said that sounds about right.That was a huge difference. I was using a 160m dipole up about 30ft at the center and 10 feet on the ends. I'm sure that wouldn't model very well but I was 56 to him. I do need to model in my sloping terrain to ocean etc.. That poorly modeled dipole that would be shooting up 90 degrees or something can go 5000+ miles. That's what I'm talking about.Why bother with a ton of wires and work unless you can see a real world difference. I'm putting in an inverted L with the FCP ground to see how that compares to my low dipole (radials are hard for me) My results will be based on - "Jack (W2XX), let me switch my antenna and tell me how you copy me."If it's not a noticeable difference I might want use that extra coax connection for something else later. $.02 [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Mr. & Mrs. B and is intended for use only by the individual or entity to which it is addressed, or where ever the hell it ends up, and will almost certainly contain information that will offend a large portion of the population, which isn't our concern. If you are not the intended lucky recipient, or it appears that this mail has been forwarded to you without the proper authority of the Wizard of Email or Al Gore, you are notified that any thought, use, or consumption of this email is entirely your choice. In such case, Bon AppetitNote: A $.02 Internet Tax was charged for receiving this email and all funds were given to some family somewhere in America or the U.N Have a nice day. _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
Buck I think a lot of people have already done these kinds of tests. Tom and others have given a pretty thorough run-down of the different factors and results to expect. And, it all mostly agrees with modeling. There are a lot of real world differences such as type of ground, nearby terrain levels, buildings, overhead wires, and so on. Then, there are economic factors. About all you can do is to put up whatever you can live with at your locale. Or, you could buy a perfect location somewhere and operate a remote station via an internet link. - Wes Attaway (N5WA) --- 1138 Waters Edge Circle, Shreveport, LA 71106 318-797-4972 (Office) - 318-393-3289 (Cell) Computer Consulting and Forensics -- EnCase Certified Examiner --- -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Buck wh7dx Sent: Sunday, March 03, 2013 12:39 PM To: topband@contesting.com Subject: Re: Topband: Elevated Radials EPILOGUE I can't believe that no one has put this really important question to bed already. If I had the land and an existing vertical with a large buried radial system and another tower available.. I would try it out for the sake of Ham Radio :-)) Put up another 160M vertical.. contact a few friends from around North America or International and take some notes. Put 2 1/4 wave elevated radials up in the air.. 10ft. Then try 30ft.. take some notes. How did the control sample compare (buried radials). Should give you an idea of propagation and changes. Put 4 1/4 wave in the air.. (if you noticed a difference with 10ft and 30ft - don't bother with the weaker one) any difference with 4 versus 2? - I'd bet there is... Put 12 1/4 wave in the air...how does that compare? Pretty close to Control Sample??What are the real world results. If it's one "S" unit and I don't need to lay a mile-plus of wire buried in the ground.. that might be enough. I don't think people want to have a ton of elevated radials in the air either - and I'm reading that you don't need to. If you don't want to go with elevated - then bury as many in the ground as you can - have fun... Surely, someone has the room and energy (friends) to give us all the "final" answer to this question. It would be a blast to do. We'll all pitch in some beer money. Please post the results.. :-) P.S. Can someone with a tower also test out a low dipole around 30 ft and then go to 60, 90 and 120 and post the results. I'm thinking a pulley and rope and some quick 10 minutes adjustments for real world results... that one's easy. Bryan WH7DX [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Mr. & Mrs. B and is intended for use only by the individual or entity to which it is addressed, or where ever the hell it ends up, and will almost certainly contain information that will offend a large portion of the population, which isn't our concern. If you are not the intended lucky recipient, or it appears that this mail has been forwarded to you without the proper authority of the Wizard of Email or Al Gore, you are notified that any thought, use, or consumption of this email is entirely your choice. In such case, Bon AppetitNote: A $.02 Internet Tax was charged for receiving this email and all funds were given to some family somewhere in America or the U.N Have a nice day. _ Topband Reflector _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
I can't believe that no one has put this really important question to bed already. Since the results vary with installation and soil, and since no one considers "it depends" a good answer, the debate will never end. If I had the land and an existing vertical with a large buried radial system and another tower available.. I would try it out for the sake of Ham Radio :-)) I've already done that using field strength readings. I'm sure others have also. P.S. Can someone with a tower also test out a low dipole around 30 ft and then go to 60, 90 and 120 and post the results. I'm thinking a pulley and rope and some quick 10 minutes adjustments for real world results... that one's easy. I already did that. I made thousands of A-B-C comparisons between high dipoles, low dipoles, and a reference vertical. For a period of time I even had two dipoles at 250 feet or so phased. The problem is what works here for what I do can be considerably different than other places and what someone else wants. VK3ZL also compared a shorter vertical with a ~100-foot high dipole for a long period of time. All of these tests were "blind" A-B tests. The problem is results vary not only with the installation and location, but also with the distance, time of day, and solar conditions. Bob and I both pretty much settled on verticals, as did ZL3REX and others. Anyone who has made extensive A-B comparisons likely gets a chuckle out of "I took down an antenna and put up another one and it was difference" statements. It takes a long time period of many direct A-B comparisons to reach dependable conclusions. 73 Tom _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
Brian and any other interested party, Although it is not exactly the test you are proposing, for all intents and purposes the information I have will give you a quite good summary of your suggested testing. Both TX antennas described below perform VERY, VERY well. I have constructed and have used for some years with excellent results at N5BG/NI5T the following installation. 40' of Rohn 25 to an insulated base. Above the insulated base is 80' of Rohn 25 with a Force 12 C4XL as a top hat. 15 each, 1/4 WL long radials slope down from 40' to ~10'-15' AGL. This past year at a location 50 miles separated from the above described installation I constructed a full sized (120' tall) ground mounted and insulated Rohn 25 vertical with 64 each, 1/4 WL long, insulated radials laying on top of the ground. This is the first time I have had the ground space to construct a 'textbook' antenna. This location was operated under the call sign N7GP. The two locations are both in DM52, one inside of New Mexico and the other in Arizona. During some of the recent Top Band contests both stations have been active simultaneously and have been received by various RBN sites around the country. I have a set of jpeg images of the comparisons of the signals from the two stations at 8 different RBN sites across the USA during the CQ 160 CW 'test at the end of January. Both stations were running legal limit power over a period of ~3 hours providing an excellent comparison of signal strength at various distances from DM52. The images are only about 40 Kb per image, so they are not large files. I will be glad to send them to anyone who requests them in a direct E-Mail. I also have high resolution jpeg images (2-3 Mb) of the towers and close up views of certain parts of the antennas for those who are more interested in the details and might like to view those also. Happy Monday to everyone out there in radio land. de Milt, N5IA -Original Message- From: Buck wh7dx Sent: Sunday, March 03, 2013 11:38 AM To: topband@contesting.com Subject: Re: Topband: Elevated Radials EPILOGUE I can't believe that no one has put this really important question to bed already. If I had the land and an existing vertical with a large buried radial system and another tower available.. I would try it out for the sake of Ham Radio :-)) --SNIP-- Bryan WH7DX - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.2899 / Virus Database: 2641/6135 - Release Date: 02/26/13_ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
I can't believe that no one has put this really important question to bed already. If I had the land and an existing vertical with a large buried radial system and another tower available.. I would try it out for the sake of Ham Radio :-)) Put up another 160M vertical.. contact a few friends from around North America or International and take some notes. Put 2 1/4 wave elevated radials up in the air.. 10ft. Then try 30ft.. take some notes. How did the control sample compare (buried radials). Should give you an idea of propagation and changes. Put 4 1/4 wave in the air.. (if you noticed a difference with 10ft and 30ft - don't bother with the weaker one) any difference with 4 versus 2? - I'd bet there is... Put 12 1/4 wave in the air...how does that compare? Pretty close to Control Sample??What are the real world results. If it's one "S" unit and I don't need to lay a mile-plus of wire buried in the ground.. that might be enough. I don't think people want to have a ton of elevated radials in the air either - and I'm reading that you don't need to. If you don't want to go with elevated - then bury as many in the ground as you can - have fun... Surely, someone has the room and energy (friends) to give us all the "final" answer to this question. It would be a blast to do. We'll all pitch in some beer money. Please post the results.. :-) P.S. Can someone with a tower also test out a low dipole around 30 ft and then go to 60, 90 and 120 and post the results. I'm thinking a pulley and rope and some quick 10 minutes adjustments for real world results... that one's easy. Bryan WH7DX [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Mr. & Mrs. B and is intended for use only by the individual or entity to which it is addressed, or where ever the hell it ends up, and will almost certainly contain information that will offend a large portion of the population, which isn't our concern. If you are not the intended lucky recipient, or it appears that this mail has been forwarded to you without the proper authority of the Wizard of Email or Al Gore, you are notified that any thought, use, or consumption of this email is entirely your choice. In such case, Bon AppetitNote: A $.02 Internet Tax was charged for receiving this email and all funds were given to some family somewhere in America or the U.N Have a nice day. _ Topband Reflector
Re: Topband: Elevated Radials EPILOGUE
Good Day All, Well, after sifting through all of the responses to my original posting, and reviewing the different sites recommended by specific denizens of Topband, I've come to the conclusion that I will have to stick to my current design of 24 radials, each 1/8-wave long, per "L"... I believe that a minimum of two elevated radials would be the absolute minimum that I would have liked to try at my location---unfortunately, physical limitations of the property here would allow extended radials (i.e. going off in opposite directions to one another) beneath just one element in my 3-element array: the other 2 elements would benefit from a fully extended (& elevated, of course) single radial only, with the other "twin" being meandered about the property lines of the real estate that is available here... While this arrangement might prove to be an effective compromise of sorts---compared to the questionable system that I currently employ---I don't know that I'd want to commit next year's Topband DX season to an arrangement that might be grossly inferior to what I now have, as tempting as any elevated set-up might be...and the current ground system has carried me through some 7 years of reasonably reliable & faithful service to date... So---bad knees notwithstanding!---I guess I'll have to stick to the "tried & true" here, & hope that the propagation gods might render me better assistance next season, than they have this year. Thanks again for all of the input that I received from everyone... ~73!~ de Eddy VE3CUI - VE3XZ _ Topband Reflector
