Thank you both very much for focusing on elevated radials! I've been preaching the benefits to POTA activators (and any ham who would listen) for almost 5 years now. Just one correction, @8:10 you mentioned my POTA PERformer antenna with two elevated radials. They should be 90 degrees apart (not 60 degrees) for higher efficiency, gain and slight directivity within the span of the radials. And both of these radials are linked radials providing incremental wire (via spade connectors) for each band. However, I don't have to extend the wire for each band, I just insert a short non-conductive segment in the line to terminate the radial at that point for the band of operation. I'm always happy to share my free PDF with anyone that's interested in the computer models, photos, parts list and complete build instructions. Keep up the great work gentlemen! 😀73 KJ6ER, California
Or would laying out the radials with a 60 degree separation create greater directionality? At this point, I'm probably the last person to try figuring that out by modeling, so I ask others who may have the answer.
@@Sagart999 When I computer modeled the PERformer antenna, I tried a variety of radial spans from 20 degrees to 120 degrees, looking at both the modest gain and directionality they provided. I found through multiple iterations that the 90 degree span provided the optimal span for both factors. As radials move closer together, they interact (which is not good) compromising the gain and disrupting the antenna radiation pattern. I recommend using 90 degrees 😀73 KJ6ER
Great show as always. If you’re looking for an idea for another show, for those of us who don’t have the electronic knowledge if you were too, take the points that you’re making in the show but draw them out on a diagram. Example front to back signal to noise ratio. If you were to draw that out to help make it more understandable that would be a great show. Thanks so much for all you do.
I have owned a SteppIR Crank-IR portable antenna for several years. It takes more time to setup than I would want for POTA but I do use it for Field Day and backyard operation. It uses a reel to adjust the vertical wire length against a fiberglass pole and a single radial with a reel to adjust the length when changing bands. I tune it with a Rig Expert analyzer. I use 2 electric fence poles for the ends of the radial. It needs 2 supports to allow the wire to return to the reel when adjusting. It works very well and is directional in the direction of the radial. I have also used a single elevated radial with a Buddi-stick vertical on a tripod. Buddipole sells a wire winder to use for the radial. You tune by changing the wire length on the winder. You do need to move the end support though. Phil, N3ZP
I have just built the PotaPerformer per Greg Mihran's plans (using the PVC PIPE and mirror mount with 17' Chameleon SS Whip). My goodness what a nice resonant antenna! At mid band phone SSB on 20-17-15-12M my SWR were 1.3 or less! On 10M I was at 1.5 SWR but did not put in enough effort to dial in the SWR. I noticed that IF you forget to take out (or adjust the counterpoise length) via the link(s) the SWR for that specific band is not good. So then the raised linked counterpoise is indeed a part of the radiating system. I have yet to experiment with the counterpoise height(s) and thus the angles. Also, perhaps RCA or Banana Plugs could be used for joining the links if you happen to have them handy. Also at Tractor Depot, they have plastic fence posts with a metal spike at the base which are REALLY nice for the linked CounterPoises' Thanks to you all... on with the FUN! Art W1SWL
The 4dB front to back seems plausible with the single radial. But don’t forget that this means that the weaker side is now weaker than an omni directional 1/4 wave and that the stronger side with the single radial is only about 2dB stronger than an omni directional vertical with 2 raised radials at 180 degrees from each other. So establishing the initial baseline for measuring is pretty critical in the first place.
I've been using the 1/4 vertical with 2 elevated radials for a while and it has been performing very well. If you haven't tried this yet please do! I haven't made linked radials but have some cut for 20m-6m. I also made a lightweight version for SOTA, that uses a wire vertical and a banana plug. One thing to note is you need a choke at the feed point to prevent the coax from becoming part of the counterpoise. --K5OHY
Correct. The common mode choke at the antenna feedpoint is very important. I've only recently begun experimenting with the 2nd elevated radial. There is significant interaction with the first tuned radial, that I haven't totally conquered yet. I'll get there.😅 KZ9V KZ9V
I will be trying a variation when we are on top of a hill next to a lighthouse at Cooktown, Far North Queensland, Australia, for the lighthouse weekend. It will be a telescopic whip mounted on a four metre high stainless steel tripod. The interesting test will be how much that tripod acts as a counterpoise, whether we still need a wire counterpoise (which I suspect we will), whether the counterpoise length will still be a quarter wavelength or shorter, and whether it will be better to drop the tripod to its lowest height of about a metre. Lots of questions but no answers yet.... VK4BOB
That’s the sun of ham radio. You never know until you try, but even then past performance does not guarantee your future signals I’m going back to mag loops. Having a bit of success, but I’d like to do some comparisons between them and my vertical
Very interesting!! So only one tuned counterpoise is sufficient? Is there a preferred direction where the counterpoise is pointing when laid out?? I wonder if you can do a fanned counterpoise to cover all the bands being tuned laid in the direction you wanted? what tool do you use to tune, just via vswr? I have a NanoVNA?
Built mine this weekend. Got contacts on 20, 17, and 15, but 12 and 10 are dead this weekend. Radio is a QDX, and QTH is "in a hole." I was having a QSO with someone 1000 km away who assured me that it didn't work. Basically, this thing is a bent dipole, with one leg vertical.
Yes. That's pretty much it. And we all know that monoband dipoles work great. But in many portable deployment situations, the necessary supports for a dipole aren't available, so something like this vertical with an elevated tuned radial is a very viable alternative. KZ9V
Recently tried center-loaded 12 foot endfed vertical with one 12 foot radial on plastic fence post with folded faraday cloth attached at the end (near the top of fence post). First contact on 20 meters S7 into Brazil from my midwest location. In other words, the raised, folded faraday cloth can keep the radial shorter than usual, good for public spaces. I will have to try two radials at 60* and see if that helps. ❤❤❤
Unless the 12 ft. radial wire was also center loaded (like the 12 ft. vertical element it's not going to be a tuned radial. I'm trying to visualize the role of your Faraday cloth. Does the Faraday cloth touch the ground, or is it elevated just like the 12 ft. radial wire? KZ9V
@@davewhite7679 radial clips to folded faraday cloth near the top of the plastic fence post. Nothing is touching the grass or dirt. Faraday cloth was simply folded into a tight 20 x 4 inch rectangle held together with plastic spring clips. The alligator clip at the end of the radial hung down a couple inches from the top of fence post to (loosely) hold up the cloth. I will further experiment with wrapping the cloth around the plastic fence post and securing it better with velcro strips. I had S7-S9 signals into Europe during the IOTA Contest (same session). I think raising the faraday cloth at the end of the raised radial has merit and needs further trials.
I use one of the cheap Ali Express 1/4 wave verticals 3ft of the ground. Tuned linked radial for 20-10 m 3ft off the ground. New Zealand to Toronto Canada 9,000 miles with 20w lasr week. 73 Steve ZL1YX
I have purchased a used multi band vertical (I have not installed it yet). How do I tune both the antenna and the radials? Do you have a video regarding this? This commercially made antenna is 10 meters through 80 meters.
The real question is 6 dB gain compared to what. The yagi numbers are usually compared to a dipole or an isotropic radiator. I’m guessing the 6 dB number is compared to a ground mounted vertical. Not the same thing at all. As to the ground plane elements, I like to end the element into a small bungee cord. Say 1/4 inch diameter and about a foot long. Attach the other end to the anchor. The elastic keeps the wire taunt, with a bit of give if needed.
Correct. In my testing of the single elevated tuned radial, the 6+ db gain figure is more accurately described as the front-to-back ratio favoring the direction of the single radial. The 4+ db "gain" was the actual performance improvement (in the direction of the single radial) compared to traditional ground wire radials or Faraday cloth ground plane deployment. KZ9V
Yes it is. The Buddistick comes with a counterpoise that's on a winder. You can lengthen or shorten the wire depending on what frequency you are transmitting on. That process is a little cumbersome, but you can use the linked radial idea with the buddistick for a faster setup.
Absolutely! Elevating just 2 tuned (quarterwave) radials increases the radiation efficiency for any quarterwave antenna to over 90% versus 2 surface/ground radials with only about 30-35% efficiency. But remember, elevated radials need to be 'tuned' for the band of operation while ground/surface radials do not. That could be a construction challenge as you tune the screwdriver across the bands. In that case, you would need to include two elevated tuned radials per band which would be a lot of elevated radials for a portable or mobile operation. Not so much of an issue if permanent 😀73 KJ6ER
@@KU8RLY Roger! Great location up high. Yes, u can drape 2 radials per band on ur roof … you can consider them already elevated. I did the same thing a while back with a Tarheel screwdriver and it worked great. Keep the same band radials opposite each other 😊 73 KJ6ER
I am using my portable JPC-12 at home for 10 meters. The antenna feed point is elevated roughly 4 1/2 feet using the extensions and ground spike. I have 2 elevated radials that are roughly 1 1/2 feet at the ends. South facing radial is tuned and north facing radial is untuned. This configuration has given me a 1.02:1 SWR across the enter technician segment of the band. My question is do you think this still gives me an omnidirectional pattern, or would it be stronger in the direction of the tuned radial?.......KC1UER
Without knowing the exact length of the 2nd radial and some computer modeling, it's hard to say for certain. My guess is that there's probably minimal current flow in the untuned radial and that it's having almost no beneficial impact on either the impedence match or performance. KZ9V
@@davewhite7679 the untuned length is about 18 feet. When I tried to shorten it to match the tuned radial, the SWR went way up. The nanoVNA shows an impedance of 49 ohms at lowest SWR reading.
@@KC1UERMuch like you, I've recently been experimenting with adding a 2nd tuned radial. I have noticed some significant detuning of the first radial when the 2nd radial is attached, so that's still a work in progress with mine.😂 KZ9V
Thank you both very much for focusing on elevated radials! I've been preaching the benefits to POTA activators (and any ham who would listen) for almost 5 years now. Just one correction, @8:10 you mentioned my POTA PERformer antenna with two elevated radials. They should be 90 degrees apart (not 60 degrees) for higher efficiency, gain and slight directivity within the span of the radials. And both of these radials are linked radials providing incremental wire (via spade connectors) for each band. However, I don't have to extend the wire for each band, I just insert a short non-conductive segment in the line to terminate the radial at that point for the band of operation. I'm always happy to share my free PDF with anyone that's interested in the computer models, photos, parts list and complete build instructions. Keep up the great work gentlemen! 😀73 KJ6ER, California
Or would laying out the radials with a 60 degree separation create greater directionality? At this point, I'm probably the last person to try figuring that out by modeling, so I ask others who may have the answer.
@@Sagart999 When I computer modeled the PERformer antenna, I tried a variety of radial spans from 20 degrees to 120 degrees, looking at both the modest gain and directionality they provided. I found through multiple iterations that the 90 degree span provided the optimal span for both factors. As radials move closer together, they interact (which is not good) compromising the gain and disrupting the antenna radiation pattern. I recommend using 90 degrees 😀73 KJ6ER
Great show as always. If you’re looking for an idea for another show, for those of us who don’t have the electronic knowledge if you were too, take the points that you’re making in the show but draw them out on a diagram. Example front to back signal to noise ratio. If you were to draw that out to help make it more understandable that would be a great show. Thanks so much for all you do.
Got mine built, trying it Tuesday
I have owned a SteppIR Crank-IR portable antenna for several years. It takes more time to setup than I would want for POTA but I do use it for Field Day and backyard operation. It uses a reel to adjust the vertical wire length against a fiberglass pole and a single radial with a reel to adjust the length when changing bands. I tune it with a Rig Expert analyzer. I use 2 electric fence poles for the ends of the radial. It needs 2 supports to allow the wire to return to the reel when adjusting. It works very well and is directional in the direction of the radial. I have also used a single elevated radial with a Buddi-stick vertical on a tripod. Buddipole sells a wire winder to use for the radial. You tune by changing the wire length on the winder. You do need to move the end support though. Phil, N3ZP
I had radial on a 14avq vertical.trimmed them to freq. Worked great.
I have just built the PotaPerformer per Greg Mihran's plans (using the PVC PIPE and mirror mount with 17' Chameleon SS Whip). My goodness what a nice resonant antenna! At mid band phone SSB on 20-17-15-12M my SWR were 1.3 or less! On 10M I was at 1.5 SWR but did not put in enough effort to dial in the SWR. I noticed that IF you forget to take out (or adjust the counterpoise length) via the link(s) the SWR for that specific band is not good. So then the raised linked counterpoise is indeed a part of the radiating system. I have yet to experiment with the counterpoise height(s) and thus the angles. Also, perhaps RCA or Banana Plugs could be used for joining the links if you happen to have them handy. Also at Tractor Depot, they have plastic fence posts with a metal spike at the base which are REALLY nice for the linked CounterPoises' Thanks to you all... on with the FUN! Art W1SWL
Thanks guys, good things to think about and experiment with.
The 4dB front to back seems plausible with the single radial. But don’t forget that this means that the weaker side is now weaker than an omni directional 1/4 wave and that the stronger side with the single radial is only about 2dB stronger than an omni directional vertical with 2 raised radials at 180 degrees from each other. So establishing the initial baseline for measuring is pretty critical in the first place.
I've been using the 1/4 vertical with 2 elevated radials for a while and it has been performing very well. If you haven't tried this yet please do! I haven't made linked radials but have some cut for 20m-6m. I also made a lightweight version for SOTA, that uses a wire vertical and a banana plug. One thing to note is you need a choke at the feed point to prevent the coax from becoming part of the counterpoise. --K5OHY
Correct. The common mode choke at the antenna feedpoint is very important. I've only recently begun experimenting with the 2nd elevated radial. There is significant interaction with the first tuned radial, that I haven't totally conquered yet. I'll get there.😅
KZ9V
KZ9V
Good stuff, Gents. Thank you.
I will be trying a variation when we are on top of a hill next to a lighthouse at Cooktown, Far North Queensland, Australia, for the lighthouse weekend. It will be a telescopic whip mounted on a four metre high stainless steel tripod. The interesting test will be how much that tripod acts as a counterpoise, whether we still need a wire counterpoise (which I suspect we will), whether the counterpoise length will still be a quarter wavelength or shorter, and whether it will be better to drop the tripod to its lowest height of about a metre. Lots of questions but no answers yet.... VK4BOB
That’s the sun of ham radio. You never know until you try, but even then past performance does not guarantee your future signals
I’m going back to mag loops. Having a bit of success, but I’d like to do some comparisons between them and my vertical
I use fiberglass fence poles to elevate my radials, as many as 3 used for the 40M band, lol. Davey - KU9L
Very interesting!! So only one tuned counterpoise is sufficient? Is there a preferred direction where the counterpoise is pointing when laid out?? I wonder if you can do a fanned counterpoise to cover all the bands being tuned laid in the direction you wanted? what tool do you use to tune, just via vswr? I have a NanoVNA?
Built mine this weekend. Got contacts on 20, 17, and 15, but 12 and 10 are dead this weekend. Radio is a QDX, and QTH is "in a hole." I was having a QSO with someone 1000 km away who assured me that it didn't work.
Basically, this thing is a bent dipole, with one leg vertical.
Yes. That's pretty much it. And we all know that monoband dipoles work great. But in many portable deployment situations, the necessary supports for a dipole aren't available, so something like this vertical with an elevated tuned radial is a very viable alternative.
KZ9V
Recently tried center-loaded 12 foot endfed vertical with one 12 foot radial on plastic fence post with folded faraday cloth attached at the end (near the top of fence post). First contact on 20 meters S7 into Brazil from my midwest location. In other words, the raised, folded faraday cloth can keep the radial shorter than usual, good for public spaces. I will have to try two radials at 60* and see if that helps. ❤❤❤
Unless the 12 ft. radial wire was also center loaded (like the 12 ft. vertical element it's not going to be a tuned radial. I'm trying to visualize the role of your Faraday cloth. Does the Faraday cloth touch the ground, or is it elevated just like the 12 ft. radial wire?
KZ9V
@@davewhite7679 radial clips to folded faraday cloth near the top of the plastic fence post. Nothing is touching the grass or dirt. Faraday cloth was simply folded into a tight 20 x 4 inch rectangle held together with plastic spring clips. The alligator clip at the end of the radial hung down a couple inches from the top of fence post to (loosely) hold up the cloth. I will further experiment with wrapping the cloth around the plastic fence post and securing it better with velcro strips. I had S7-S9 signals into Europe during the IOTA Contest (same session). I think raising the faraday cloth at the end of the raised radial has merit and needs further trials.
I use one of the cheap Ali Express 1/4 wave verticals 3ft of the ground. Tuned linked radial for 20-10 m 3ft off the ground. New Zealand to Toronto Canada 9,000 miles with 20w lasr week.
73 Steve ZL1YX
I have purchased a used multi band vertical (I have not installed it yet). How do I tune both the antenna and the radials? Do you have a video regarding this? This commercially made antenna is 10 meters through 80 meters.
The real question is 6 dB gain compared to what. The yagi numbers are usually compared to a dipole or an isotropic radiator. I’m guessing the 6 dB number is compared to a ground mounted vertical. Not the same thing at all.
As to the ground plane elements, I like to end the element into a small bungee cord. Say 1/4 inch diameter and about a foot long. Attach the other end to the anchor. The elastic keeps the wire taunt, with a bit of give if needed.
Correct. In my testing of the single elevated tuned radial, the 6+ db gain figure is more accurately described as the front-to-back ratio favoring the direction of the single radial. The 4+ db "gain" was the actual performance improvement (in the direction of the single radial) compared to traditional ground wire radials or Faraday cloth ground plane deployment.
KZ9V
Is the Buddistick Pro an example of a elevated counterpose antenna?
Yes it is. The Buddistick comes with a counterpoise that's on a winder. You can lengthen or shorten the wire depending on what frequency you are transmitting on. That process is a little cumbersome, but you can use the linked radial idea with the buddistick for a faster setup.
Great topic!!! 73!
Im.curious. would elevated radials also help a screwdriver antenna, such as the atas?
Absolutely! Elevating just 2 tuned (quarterwave) radials increases the radiation efficiency for any quarterwave antenna to over 90% versus 2 surface/ground radials with only about 30-35% efficiency. But remember, elevated radials need to be 'tuned' for the band of operation while ground/surface radials do not. That could be a construction challenge as you tune the screwdriver across the bands. In that case, you would need to include two elevated tuned radials per band which would be a lot of elevated radials for a portable or mobile operation. Not so much of an issue if permanent 😀73 KJ6ER
@gregmihran8616 I ask, because I mounted an atas120 on the roof on my home, and I just have a couple radials laying across the roof of my home.
@@KU8RLY Roger! Great location up high. Yes, u can drape 2 radials per band on ur roof … you can consider them already elevated. I did the same thing a while back with a Tarheel screwdriver and it worked great. Keep the same band radials opposite each other 😊 73 KJ6ER
Thanks !
I am using my portable JPC-12 at home for 10 meters. The antenna feed point is elevated roughly 4 1/2 feet using the extensions and ground spike. I have 2 elevated radials that are roughly 1 1/2 feet at the ends. South facing radial is tuned and north facing radial is untuned. This configuration has given me a 1.02:1 SWR across the enter technician segment of the band. My question is do you think this still gives me an omnidirectional pattern, or would it be stronger in the direction of the tuned radial?.......KC1UER
Without knowing the exact length of the 2nd radial and some computer modeling, it's hard to say for certain. My guess is that there's probably minimal current flow in the untuned radial and that it's having almost no beneficial impact on either the impedence match or performance.
KZ9V
@@davewhite7679 the untuned length is about 18 feet. When I tried to shorten it to match the tuned radial, the SWR went way up. The nanoVNA shows an impedance of 49 ohms at lowest SWR reading.
@@KC1UERMuch like you, I've recently been experimenting with adding a 2nd tuned radial. I have noticed some significant detuning of the first radial when the 2nd radial is attached, so that's still a work in progress with mine.😂
KZ9V