Vertical Antennas, Ground Planes and Radials for Ham Radio - MMANA-GAL
Вставка
- Опубліковано 2 сер 2021
- In this video, we discuss vertical antennas, ground planes, and radials for ham radio. We also use a tool called MMANA-GAL to do some antenna modeling.
Please consider supporting TheSmokinApe Channel on Patreon Here: / thesmokinape
Links to products in the video: www.amazon.com/shop/TheSmokinApe
As an Amazon Associate I earn from qualifying purchases.
Check out my Antenna Playlist: ua-cam.com/users/playlist?list...
If you liked this video you can see more like it here:
/ thesmokinape
You can also follow me on Twitter and Instagram:
/ thesmokinape
/ thesmokinape
I never fail to learn something from your videos. Thanks! 😀👍
Glad to hear it Jason! Thanks for the comment and the support 👍
Wow, I just got around to watching this video and it was brilliant. Once again, you've managed to explain a complex topic and have it make sense for a knuckle head like myself. I downloaded the software and it is a game changer for working with antennas. Thank you so much for this and all your other videos!
Thanks for watching Hugh, glad the video was helpful 👍
If you have a ground mounted vertical with 4 1/4 wave radials, you will actually improve your signal by cutting the radials in half and using the extra wire in order to make 8 1/8 wave radials which uses the same total length of wire. This generally holds true for 16 or less radials.
Nice vid BTW. 73 de WD5DHK
Thanks for the comment Ray and for checking out the video!
Nice illustration of antenna modeling Ape
Thanks Kevin, glad you liked it 👍
Great video Ape! I like the approach of your comparisons between the vertical and dipoles at different heights.
Thanks HoH, glad you liked it 👍
Great video Mr Ape. Very easy to see comparisons between antennas without breaking a sweat. Very helpful.👍🤠
Thanks Don, glad you liked it 👍
Great way of showing the different radiation patterns for the antennas. Also the ever increasing Subject of radials. Cheers, 73
Thanks Gary, glad you liked it 👍
What a Great 'Simple' vidclip..... So well explained and demonstrated .... Best wishes to ALL from NZ
Howdy Keith, glad you liked it!
You’re well grounded Ape. Looking forward to this one
Lol, thanks Hayden 👍
Great video!!! Never did I understand ground plane when my grandfather explained it. Then again, I was seven years old :-) lol As I got older and was studying for my Tech lic. it hit me. He always would use a door screen as a mat for the antenna to sit on eliminating ground rails. I also recalled him sanding the coating off the four surrounding ends of the "Door Screen mat" and connecting four short wires to each corner with alligator clips. I used the same setup to this very day for ground plane. Great times, great memories, again wonderful video. Thank You!!!
Glad you liked the video and thanks for watching. Also, the door screen ground plane has been shown in a few recent videos... what's old is now as they say!
What a great video! I'm just starting out and need some basics on antennas. Thank you.
Glad you liked it Jeff, thanks for watching!
You know I watch ALOT of ham radio videos here on UA-cam. Yours are the only one where at the finish I do not have more questions then when I started.
Awesome John, thanks for watching 👍
Fantastic job on covering this information 👍👍
Glad it was helpful 👍
Another great video! MMANA-GAL is a great tool!!
Thanks Bearded Ham, it is a pretty handing tool for sure!
Good video, great explanation and I learned a great deal about antenna's!! Good work and I'll be watching more of your videos!
Hey Keyser, glad you liked it 👍
On par with the Great Ape's, er, the Great Ape .... you. Like your explanations and the way you present. And as you often call attention to, the superb artwork. Give us more!!! A patron.
Haha, thanks for the support and for checking out the video! Glad you liked it 👍
Very good and clear demo of the use of that modelling software. 👍👍👍
Could you address the question of optimizing radials for a multi-band ground-mounted vertical, please.
Thanks James, glad you liked it... I will put the multi-band vertical on the list.
The ground de-tunes radials , so ground mounted antennas dont need quarter wave radials. They need to return as much energy as the can to the ground plate collector under the antenna. That way the ground losses are reduced. A ground mounted antenna will aproach 36+jO near resonance and with a great ground image ..so any ground resistance is seen in series with radiation resistance. Having lots of symetrical radial ( spokes ) helps keep down the ground loss resistance. My personal experience is s minimum of 30 radials at least 25 ft for the lower bands these will be better as well at higher frequencies. Broadcast Engineers for AM stations usually put down over 100 radials to ensure low ground losses and low angle coverage.
Great info Dean, thanks!
Don't forget Dean under 90 degrees your mast is capacitive reactive. Thus electrically it looks like a capacitor. Infact the system as a whole is. You draw the real world losses in as resistance too. Just to touch briefly on the number of radials. Volumes have been written on this. But for the very reason you can use bare or insulated radial with no difference. This means the energy is inducted as compared to conducted into the ground. Rather more like a transformer. Once max transfer is obtained .... more copper in the ground is stepping the line of diminished returns. Cheers all great work.
Nice video SA! 🤘📻⚡️ Thanks!
Thanks Tommy, glad you liked it 👍
So much great info!
Thanks Ape 👍👍
👍🍻
Great explanation! Thank you!
Thanks Gaptastic, glad you liked it 👍
Good video, very informative.
Thanks Paul, glad you liked it 👍
Wish I had watched this extremely clear and concise treatment before taking license exams....
Well I am glad you watched now, thanks William 👍
Multi-band Vertical here with 45 Radials in the main Works OK over the years. MANY... HI have learned to never put an aerial at odd Quarter Wave lengths high as main radiation goes straight up.. Great again many thanks .over 200 Countries worked with 5 Watts
Sounds like a great antenna 👍
Thanks for explaining this. It makes sense now.
HLTW TeamReplay for the win.
Glad you liked it No Code, thanks for the support 👍
For best performance sparse radials (
Thanks for the info 👍
Thanks Ape. Nice explanation of the different variables. Do both horizontal and vertical antenna types benefit from radials or just vertical antenas? In my case I have a Dipole hovering above radials that I put down for a vertical antenna, will they help it as well?
Yeah, that should help as well. We we model antennas ground composition plays a huge role in impacting radiation patterns. Given that real ground isn't the best ground (hard to believe) we can add artificial ground to help. Thanks for watching Keith!
Great Video
Thanks YAEC, glad you liked it 👍
I put up a 92' tall vertical using a drone as a skyrocketing to drop a fishing line over the tallest branch of a tree. The antenna was supported at the top by 3' of vinyl tubing tied to a nylon rope which went to the tie point on the ground. The 14awg copper wire was hanging Straight down and connected to porcelain insulator where it connects to the coax. This antenna worked fantastic. Relative to my horizontal longtime, it typi c ally was 3 to 15db higher signal strength on 75 through 20m than the reference horizontal ant.
Due to high winds, the antenna came down after 3 days of phenomenal dx.
I decided to ruggedize the improved suspension with 5' of guy wire with ptfe tubing over it so it doesn't chafe on the branch and cut the rope. There is 3 feet of vinyl cord etween the vertical wire and the guy wire, which runs horizontal across branches before going down vertical. Only the top 3 feet of wire are parallel to this steel guy wire 3 feet away. However this ruggedized antenna mount has poor performance. I thought my coax switch was wire backwards because rhe reference ant was outperforming the vertical after the update.
I am still trying to get my head wrapped around the fact that 3 feet of steel 3 feet away from. The main radiator would drastically degrade antenna se sitivity.
That is a cool sounding antenna, it is crazy how "stuff" can impact an antenna so much.
@@TheSmokinApe I'm starting to think propagation conditions are partly to blame. A couple of days later, and on some bands, the vertical does better. But there are still 2/3 of the stations come in better on the horizontal, particularly on 75m. My last vertical excelled on 160m, but this one seems to be about the same as the short horizontal wire.
Still not sure if the short length of guy wire up at the top is influencing the performance. I plan to test the coax this week and find out if there's damage somewhere along its length.
nice post. Any thoughts on those folks using window screens or chicken wire or faraday cloth for their ground planes?
Thanks Anthony. I’m sure those materials are good for capacitive coupling to the Earth but I’m also concerned with ground loss so I want a big field…. I’m gonna stick with radials 👍
Question, which part or section of a vertical antenna does the most radiating?
Thank you for the informative video.
It depends on the height of the antenna; a 1/4 wave will have more current at the bottom while a 5/8 wave will have more at the top.
Do you have any 3D pattern pictures of what happens if I can only lay out radials in 180deg?
great video. So would radials function as the ground plane if a 2m omni was mounted at 20m? What is the best antenna type to use on a tower and how would I go about determining the antenna mounting height? Thanks
The don’t as the ground plane. With elevated antennas to need to tune the radials which is easy enough. For a tower mounted 2m I’d look at the comet gp antennas 👍
So at what point do you measure a vertical dipoles height? The center feed? Nice presentation!
Yeah, at the feed point. Glad you liked it and thanks for watching LC 👍
Thank you for a well-explained video... 👍👍👍👍 (if I had 4 hands 😀 )
Haha, glad it was helpful!
I've just installed a 20M homebrew quarter-wave vertical mounted at about 7 ft up. I cut one radial of the same length as the vertical, and strung it horizontal a bit over 6 ft up in the air. I trimmed it to an almost 1:1 SWR. I didn't use a balun, rather, a simple (dipole) center insulator. From what I have read, the pattern of the antenna signal won't change that much in my scenario. Have you heard anything different than that? I'm going to do the same thing with a homebrew 15M quarter wave vertical soon.
I'd use at least one, the way you describe. Add more would make the antenna more omni-directional 👍
Could you show what would happen if you did however have an antenna against a fence, or in my case, the rear window of my truck and added 2 to 4 radials? You mentioned it would be an inconsistent radial pattern, but it's the only option for me. Is it better do not do anything or add a few radials to at least have some sort of radial pattern--even if it is "inconsitent"? By the way, I subscribed and liked, great info and content. I love the details and data shown on the computer vs. someone just talking without showing evidence.
In the case of your truck the actually truck is the ground plane and there’s no or minimal need for radials. I’m not sure how to model the truck as the ground plane 👍
Extremely good demo. I do have a question though that I would really like explained. How does a ground plane look modeled from a pickup truck that DOES NOT use a roof mount? I like many others, don't want to damage the roof of my truck. Therefore, after a ridiculously difficult search for such a mount, I found one for the rear edge of my bed, knowing full well this isn't deal for a ground plane, but it works. I'd like to see a model of such a mounting to see just how non-ideal it technically is. This also would apply to a commercial solution such as an ATAS-120 expected to be mounted on a bumper...
Thanks!- WA8QQU
So there is a few things here, you are right without a uniform ground plan you will get inconsistent radiation pattern. I'm not sure a vehicle, regardless of mount location would be anything but a compromise ground plane. You also have the issue of grounding (not ground plane) to make sure you have low noise an minimal interference. Thanks for the comment Dale.
Many thanks, very clear and useful
Will try to get that modelling programme.
Peter CT7ADL
Thanks Peter, it is pretty fun software to play with 👍
Nice video ... thank you.
Im looking to put my multiband vertical on top of my steel shed, but 1/4 lambda radials for each band is going to be a challenge, especially 40m and up.
Ive seen mfj and others, and also homebrew artifical ground tuning units. Im wondering if this would aleviate the need for measured (1/4 wave) radials?
Any thoughts?
Hey Luke. If you mount above ground you will need tuned radials for each band you want to work as you mentioned. If you mount on the ground the radials no longer need to be tuned.
@@TheSmokinApe hmmmm .... been thoroughly reading the chapters on the effects of ground in the ARRL Antenna handbook. Seems that alot of the onterpretation revolves around a minimum of 4 radials ... when the number of radials increases, the coupling between radials reduces the need for tuning of those radials.
What kind of ground do i choose when i put the ground plane on a concrete roof with “roofing” on it ?
How do i setup the simple vertical file like the one you are using?
If you are not mounted on the actual ground you will need to tune your radials to the lowest frequency you will be working, and that ain't very easy. This was an included file that I edited. Good luck with the project and thanks for watching Albert.
Learn something with every video
Awesome, as always thanks for the support Thump 👍
Bro I made my first antenna today a dipole, with a BNC connector and copper wire I striped off old cable T.V coax if that's what it is called lol and soldered them to electric connectors the ones with the hole in it lol, that I connected to the BNC post. I can't solder if my life depended on it. They look not that good but its solid. I ran it throw the Nano VNA-H4 my wife just got me alls I had to do was make is shorter and its ready to go. Going to try it out tomorrow, I have a question I'am gone make a ground plane antenna how big can the sheet of copper be that I attach the radials to its for UHF and it will be off the ground at least roof high and can I use copper ? Every video I see they use aluminum.thanks for making videos and sharing your knowledge.
You can use copper to make a ground plane, I would make the radials 1/4 wave of the lowest band you will operate on. Good luck!
Hi Mr Ape. Question: If we put down radials in order to improve conductivity of the ground, why does all videos regarding this subject show insulated wire radials? Would bare copper radials not be better? Second question: All videos shows multiple single wire radials spreading in all directions from the centre point. What would the effect be if we for instance weave a "net" of bare copper wire with the same radius as the single wire radials? In the case of such net, should it be insulated from the physical ground (sand/soil) or bare copper on the ground? I have watched hours and hours of videos on radials but still have these questions keeping me awake at night 🙂
Hi. I suppose bare copper would be better but would probably suffer from corrosion issues. And if you think about it, most elements do have some insulation on them. I think the net would help with ground reflection, I like that idea 👍
I have a Stryker sr-2k antenna mounted on the trunk of my ford crown Victoria p71 and I was wondering how many radials on a ground plane should I use to improve a great deal,oh and my swr is 1:00 on channel 1 and 1:00 on channel 40 right now I want to know if the ground plane would help for the better Thank You Happy Holidays!
Hey Terell. It's my understanding that for mobile installs the vehicle is actually used as a ground plane and radials are not necessary.
Ok I appreciate the info take care and Happy Holidays
On a vertical mounted on the ground, what if one uses a large plate of metal (aluminum) instead of individual ground plane wires? Would that work?
It would, you might have to play with the dimensions 👍
Cool program. Is that available for purchase or fred down load? It would come in handy.
Hey Chris, they have a free and a paid version: gal-ana.de/promm/Help/
@@TheSmokinApe Thanks for the link. I will check it out!
i was expecting the graphs scale to change when adding the comparisons, assuming the scale was in dbs, and it seems to me the scale is in distance, am i right?
In dB
I don't understand why we get more and more gain in every direction when you add more radials? Is it changing the effieciency of the antenna perhaps? I always thought gain was achieved by compressing the beam and focusing it to where you want it.
You are correct in that it is about compression of the radiation pattern. The radials stop signals from being absorbed into the ground and help with that compression.
Yes, it is an increase in efficiency. In other words, reducing losses.
A typical AM broadcast station has 120 radials, 1/4 wave in length. The purpose is to reduce losses to near zero.
I have heard that 1/2 wave antennas don't need a ground plane is this correct?
No. Any vertical will perform better with a ground plane 👍
how about verticals mounted above ground, say 10' for 20 meters? and how about radials?
When you mount above ground, you would use tuned verticals. I have not done a video modeling that.
Should I ground my mag-mount antenna?
You can but many people just mount them to stuff like cookie sheets for a ground plane 👍
Would a metal roof work as a ground plane?
Yeah, plenty of people do that 👍
Refracted or reflected back down to earth from the Ionosphere?
Reflected is probably the better word.
Refracted
If you can lose performance by having a dipole to high… Can you lose performance on a vertical by having the radials be too long?
It will have an impact but not necessarily a negative one 👍
No...the ground plane gets a reflected image of the monopole but negative. That forms the other leg of the dipole. That projected charge distribution onto the ground plane is spread out, and electrically looks like another leg of the antenna with opposite polarity. If you draw this on a graph centered on zero, you'll notice that the left and right sides will cancel out when added. That forms the equivalent charge at the origin of the graph. Then the y axis charge is reflected into the -y side. Bam...you get the second leg.
The radials do not need to be 1/4 wave, try 1/8 and go up. Most of the electric field will be close to the center of the monopole b/c E ~ 1/r^2.
A ground plane cannot reflect, b/c it has a very low impedance. Current wants to flow there. The actual ground can be reflective when it's got enough minerals in it for support an electric field (dielectric) but too much resistance to conduct currents well. The reason to use a vertical antenna is b/c you want a transverse wave. If you wanted to send signals up for NVIS, an inverted V dipole works well, or a slant EFHW.
You can reduce the number of radials if you connect them in a circle.
This is helpful information, thank you.
@@TheSmokinApe I admit I had to review a lot of material lately so it's fresh in my mind.
U don't always have to have radials .. on a end fed antenna the antenna will use any structure near or earth or ..the coax itself will.be the counterpoise... Now in traditional antenna theory...the more radials the lower the impedence at the feed point ..also the better the counter poise the lower the standing wave ..and lower take off angle of radiation.. the veeticle antenna that's end fed at very low height the radial isn't needed ...because it uses the coax and earth ...but at very hight heights the veeticle will perform better with radials...with this being said height is not always best without counterpoise .at hight veeticle antenna... But at very low height without radials can work DX very well and very forgiving...don't even need
No you don't "need" them, its better if you do...
Im curious... with all the AI floating around these days... has anyone asked one of these programs to model the perfect antenna?
Id be curious to know that result (i mean, if they can do art...?)
I haven’t heard of anyone doing that but it seems like a pretty god idea 👍
Don't these radials become an obstacle for mowing the lawn?
They sure can. Some folks will burry them in inch or so below ground or use ground clips to keep the in place.
Haha, thanks for the support DK5ONV 👍
@@TheSmokinApe You welcome buddy, you doing a great job and that needs to be honored big time
Either you like those headphones or sum one is dictating through them 😉😆which is it ?? ☺️🤪🤔
Lol, my handler was telling me what to say! Thanks for watching Kevin 👍
This will help.
The unbalanced antenna like a ground plane,
has one (vertical element) that is changing its electrical charge at the radio frequency
and of course charge or voltage has to be between two points.
So, when the vertical element becomes positively charged,
the electric field lines are directed towards the different charges (the radials).
As this is a rapid and constant changing charge,
the changes that travel along those electric field lines create rotating magnetic fields around the path of the changes.
this causes a chain direction outwardly.
The trick is to look at your antenna like a capacitor
and draw the imaginary electric field lines that occur between the vertical (active) element and the radial(s).
Then you know that the magnetic rotating fields will rotate around the path of those lines.
Then you know that the direction of propagation is 90 degrees to the direction of the electric field lines
and away from the source.
Easy to imagine once you can picture it
and you will no longer need modelling software.
73 de VK3VKe ⚡🙏⚡
Great post and info, thanks CH 👍
@@TheSmokinApe It makes figuring our radiation patterns on typical antennas easy.
Gets a bit more complicated with much longer elements though as you have to consider the relative phasing of each part of the lengthy elements...
Easy for typical dipoles and ground planes etc though...
Like a 1/4 wave ground plane with horizontal radials, the pattern is a line half way between the vertical and radials.
If the radials are angled downwards,
find the line half way between and that will be your take off angle. ⚡🙏⚡
73 de VK3VKe ⚡🙏⚡
@@crazyham again, fantastic info that’s spot on 👍