Vertical Antennas 101: The Importance of Radials - How Many and How Long?
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- Опубліковано 20 сер 2024
- So many permutations BUT there IS science hidden behind the myths. Allow me to untangle this in just a few minutes. Here's the link I mentioned: • 12 Volts, 6 Men and 1 ...
Here's the radial pins: www.m0mcx.co.u...
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This instruction is brilliant. Thank you for taking the time to show us newbies how to set up radials. I was going all “obsessive compulsive” prior to seeing this. Hopefully I will have my DX Singnature 9 up and running this afternoon.
Glad it helped
I have 12 radials all 2.5metres in length. I use a Hustler 6-BTV, all bands are resonant, except 80m which is just under SWR 1:2 and needs an ATU. Using my IC-705 on 10 watts, I can get a signal right around the world using FT-8/CW. The antenna is mounted in a corner of the backyard. I’m pretty happy with my results.
Callum... hope to see more videos like this! Mixing antenna theory and practical experiments is the basis of learning ham radio!
More to come!
Me to, I love these videos!
I just want to say that I put one of the radials of my DXC rapide connected to the metal roof of my house due I have a small yard and I live in a HOA area and the results experimenting with this has been extraordinary, I have converged all the world with this antenna on FT8 and SSB! Thanks for the information about radials, many of us didn't know this thing! TI2GBB - Greg
Love these videos about verticals and radials. I use stainless steel wire for my ground radials. About 200m total length of wire in a three quarter circle and it works a treat. All hide up by the AstroTurf to keep her indoors happy.
Sounds great!
Excellent video Callum 👍🏻😊 I use your DX10 wire for mine and yes, you are so right, “disappeared into the lawn” in no time!!
Nice one!
Thank for the video. I added 15 radials at 20 foot long to my wolf river coil and my signal report where 5-4 to 5-9. Thank you for the help. Now just saving money to get one of the DX commanders.
Exactly what I needed. The space I have for the Signature 9 is up against a fence and I was not sure having a 180 degree field of radials would work. This perfectly answered my questions! Thanks so much. 73
Good to hear!
Thanks Callum for cleaning this up, I’ll be mailing you on when I can pop around to purchase one. 👍
Great! Drop me a line and grab my mobile number then you can drop me SMS / WhatsApp etc..
I can’t find your email address anywhere.
Exactly what I did , stuck the vertical in the corner of the garden and ran radials at 90 dec no problem !!
Fab!
Another great video Callum. You put the ‘rubber to the road’ with you simple yet complete explanations! 73s ND4A
Many thanks!
As soon as my radials disappeared cal I re added them so now have 1,318 meters down:) classic down today being cleaned up,new cable fasteners fitted(from you) and going up again ready for cqww ssb :) love my classic👍👍
Wow!
The more radials the lower the resistance seen at the base of the antenna. I hear so much about symmetrical grounds run along the ground or drooping to get more of a longer vertical effect. But all it does is make a bunch of horizontal antennas that cancel each other out. If you only have a few ( or big ones) going to one side it acts as a folded dipole and actually puts out a nice signal in a horizontal way. As long as it matches the coax the radio doesnt care if its a symetrical ground plane which radiates little or a horizontal radiator which gets out there.
Not having a lot of radial room I was able to put the antenna in the middle of a fenced portion of the yard with about 10 to 15 ft at 360 degrees around the antenna. I cut 32 three meter radials and installed the classic with 80m with that setup. It's worked great. Signal reports from friends about 150 miles away on 80m (daily emcomm net) were the best they've ever been. I mainly use all the other bands for FT8 and it works great. We have St. Augustine grass which is a carpet type so I ordered a bag of the 2 in stakes and should have ordered 2 bags. Our dog likes to run laps around the antenna so she will pull up a piece of radial occasionally and if I don't catch it the lawnmower will clip off whatever is exposed so I'm not sure exactly what's down now but it still works fine. The radials have all disappeared into the grass now so everything is good. Thanks!! Jack K5FIT
Fabulous!
Great video Cal as always. So my garden has a classic with 160 m of radials. Works a treat. Over the summer had to take down and adjust. When I put back up I had not connected any radials! Went off with the family for the day. Came back home and did radio in the evening. Lots of good contacts. Only next morning discovered that the only grounding was via the coax haha! Pissed me off as it was back breaking to get the 160m of wire into the ground. Anyway, still glad I did. Great antenna ! Mark, 2E0MSR
Rudy is the best.........I have an autographed copy of his switching power supply book..... I run a pair of phased 1/4 wave verts on 40..............with thirty two 1/8 wave radials under each radiator. the array works........ cheers from New England to Old England, Mike K1FNX near Boston
Mike, all I can say is "Wow".
@@DXCommanderHQ Rudy is a famous switching power supply guru....... his book is one of the "Bibles"....... in the 80's every PS engineer had a copy of his book, Abe Pressman's books and "Reuben Lee" magnetics design book....... I'm retired 12 years and still have the books......
Thank you, learning something new every day before i take the plunge
Great to hear!
Thanks! I needed this video
No problem!
Thank you for explaining the effect of radials - I used your information to try and increase my DX range, but something 'weird' happended.
I have a Chameleon MPAS 2.0 portable antenna system - I set it up in the vertical configuration in my (small) back yard.
The antenna as it stands now consists of, from the ground up :
1) a ground spike (support & electrical grounding):
2) an encapsulated 'balun/unun',
3) a 133" vertical mast
4) a Chameleon 'Cap Hat'
5) finally a 105" vertical extension whip above the Cap Hat.
6) a singke 25' counterpoise / radial wire that attaches to the ground spike.
With this config I got swr's of 2.6, 1.2, and 1.75 on 40, 20, & 10 meters, respectively.
After watching your video, I cut and attached 8 (eight) 16.5' radials ( which add to a full wavelength on 40 meters) - all 14 gauge stranded copper, insulated wire.
Result: the swr's increased significantly across all bands -> 4.91, 2.55, and 2.6 on 40, 20, & 10m.
So I removed the 16.5' radials and added 2 (two) 33' (1/4 wavelength) radials, and the swr's decreased,
->( 3.2, 1.5, 2.6 for 40, 20, & 10 meters) but were still above the single 25' radial level.
This antenna, in the last config, DOES RADIATE. I have had RBN hits all the way from Hawaii, Fla, and Costa Rica, and SSB QSO's from Fla. to Alaska, all on 100 watts.
QTH is Vancouver Island on the west coast of Canada.
BUT, but, but ... these results don't make sense to me :
The 8 x 16.5' (1/8 wavelenght - which add up to a full wavelength on 40m) radials should have made the antenna MORE resonant on 40 metes, and thus should have the lowest SWR (reflected power ratio).
But it had the HIGHEST swr !
Callum, did I do something wrong, or do I just not understand the relationship between radials, resonance and swr?
Any advice would be appreciated. Thank you.
OK.. so my numbers and experiments are most appropriate to quarter wavelength radiators. Dr George Brown in the 1920/30s suggested that for smaller radiators, you need even more (as you have done actually). Now.. I honestly do not know your product that you are using and I am seriously only speculating.. So - *if* I was the designer of your antenna (and I have no real idea what it is - I am not disrespecting someone elses engineering) and it's not a quarterwave - but has coils etc than I might be tempted to give my customer the best SWR in a small to medium package. IN THE EVENT that you supply too good a radial field, it is possible the impedance went down too far, causing the SWR mismatch. We would need to understand the impedance (SWR is just a calculation from there). You *might* want to talk to the supplier and ask them politely what do THEY think is happening. They know their product and SHOULD have an idea of what is going on. Sorry for the large reply - I didn't have time to make it shorter!
@@DXCommanderHQ Thank you very much Callum. I appreciate you taking the time to reply. It's basically a 'base loaded vertical that is grounded, 19.8 ft high, with a clover leaf cap-hat half way up.
I will email Chameleon and ask them the same question.
I was also thinking about getting your new 'signatue' dx antenna now that it does not require guy wires (back yard is way too small to guy the 'dx commander'), but I would only be able to lay down multiple 1/8 lamda radials for 40m due to size restrictions.
Thank you again.
PS - Let me know if they reply to you!
As I'm watching this I'm having a few ah-ha moments, connecting dots from my license study tests and things other people have told me. I appreciate helping me KNOW what I'm doing versus just doing what someone tells me to do.
That's it!
That was enlightenment always did wonder about where to place the radials at if it made a difference
In the words of Joe Strummer, Rudie can't Fail. Thanks for addressing some questions I've had.
No problem!
Great video as always, Callum. Thank you so much for showing me how to make sense of it all. I'm soon (as soon as the postal service delivers) putting up a Hustler 4-BTV in a permanent configuration, yet the spot I have available is not conducive to laying out long radials in all directions. About 32 radials that are around 12 feet in length should do it. Thanks again for a very well done, informative, and useful video. 73 de K5SFC!
G'luck!
Quality video and great info, thank you! Nitpick, @ 1:59 the line _not_ reached is 2.6 not 2.5, each gradation is 1/5 or .2, so looks like 2.58 or so ;)
OK! I mean.. well, what can I say.. We can all see the graph.. :)
My radials are ~3 meters long because that's how far I could go in my garage (i really need to clean up!). I have 5 of them in each bundle because that's what fit into the alligator clips. I have 4 bundles because that's what fits in the bag I pack them in. I never once gave a thought to whether this is a "good" radial setup or not. It's what I can do and it makes contacts. Little point in caring beyond that I suppose.
Indeed, why worry Matt!
Pretty much what I did. Works great!
I'm using 20 radials with 2.7m, because they happened to be clones of some wire I had cut for something else.
They work great in any band I tried (40m, 15m, 12m, 11m, 10m)!
Great!
I found some surplus military comms wire zip cord 2 conductors at about 22ga steel conductors. It was 76.00USB per KM in 500m put ups. I am building a radial field using it for my signature 12.4 DXC. I am mixing 2.5m, 5m and 10m and planning to put down 640 meters total or 8X WL for 80meters. I can get 12 radials attached to each of the connectors on the ground plate. I may also look at driving four ground rods near in the radial field to give a better ground plane and connecting with wide copper strapping to the ground plate.
John, that's better than me.. And I'm starting a 160m project soon and wondering if I have enough!
@@DXCommanderHQ oh due tell 160m project... sounds great. would guess a coil loaded or inverted L with the Nebula? or a BIG Ole LOOP... ?
You are so empowering. Sent you some email (BEFORE seeing this), and thank you for humoring me.
You are so welcome!!
What about a ground plain instead of radials. A local radio station used zinc galvanized 10' width chicken wire 2" mesh covering an acre under their 3 tower AM broadcast station. They had the strongest signal in the region.
I must expect it would foil any attempts to dig a garden though, and ground hogs might hate you!
CHicken wire.. I heard about the fella that did that and was plagued with crackles and pops for years as it rusted away.
@@DXCommanderHQ The capacitance most likely .
I have dry harsh soil to spread my radials on and when they get pinned if we get the rains in california like we did last year they will melt into ground by spring.
Also ... I noticed your ham shack doubles as your music room. I am both a crappy drummer as well as a crappy guitarist. Good to see those instruments!
Haha.. Yeah, band comes around on a Thursday!
Iceland Antenna area look at all the ground radials 63°51'01"N 22°27'57"W
I'll look..
People worry too much trying to get everything perfect.
You've answered alot of questions for me Callum. Thanks for the great video. 73 de GI8WFA.
How about using wire mesh on the ground?
When replacing radials, do you dig up the old ones or just lay the new ones on top?
Good questions.. Hang fire on the wire-mesh, I'll cover that maybe later in the week..
Sent you George Brown's original paper on Discord. Beware - lots of Greek! But an interesting and comprehensive study from June 1937.
Brilliant! Thanks for the Greek :)
Hello cal I have a question when you say a 1/4 wavelength are you talking about a specific band. I know this question will help a lot of new hams including my self. If possible can you explain length in feet and cm. I’m only asking because I know how to cut 1/4 for a specific ban. But what about a multi band like your antenna which I have one and enjoy
All 1/4 wave elements are proportional to the wavelengths. To calculate a wavlength, take 300 and divide by the freq in Mhz. so 300 divide by 14.2 = 21.05 (that means 21 metres). So although we talk about the 20m band, it's actually 21 metres!). If you want feet and inches, ask Google to convert the number.
@@DXCommanderHQ thank you sir. Much appreciated
You should not use stranded wires for radials for long time.
They will soak up water and oxidize short period of time.
Therefore use only solid tinned copper wire .
The stranded wires I’ve used were all useless in less than a season .
The stranded wires were all brokened and oxidized.
Had to redo
Depends on the insulation. I have found that with DX10, it seems to soak up only a few inches - then stops.
what about a little HS tube at the ends of the radials? That would stop the moisture, yes? @@DXCommanderHQ
Anyone have a link for purchasing the green stakes Callum uses to pin down the radials
Hello! Just search google for "dx commander radial pins" and it should come up for you :)
Now I am gonna build a 1/4 wave vertical antenna. Is there any benefit to elevating the bottom of the vertical part of the antenna and sloping the radials?
Something like the Crushcraft AR2XB design, interesting. Lends to my question as to a ground plain instead of radials maybe over a steel roof on a chimney mount?
If you want to raise the vertical element of your antenna I suggest that you only raise the vertical element of your antenna by 12 to 18 inches above the ground and then you can connect the radials and let them slope from the radial plate to the ground and use at least 12 to 20 Radials for the ground plain and you will find that the antenna will have no problem with transmission or receive. I have tried several radials about four and a half feet above the ground and sloping to the ground and I have been making contacts as far away as a thousand miles from my location and made over a hundred and fifty different contacts from my vertical antenna. At present I am only using 8 radials for my antenna. I have been on 40 meters and twenty meters when I was making the contacts. So yes you can slope the radials and and be able to make contacts with your antenna.
None at all. Rudy also did some work on this.. For any REAL giain, you need to get your HF antenna WAY UP in the air. However 4 raised radials WILL work but Rudy discovered some weird "sh*t" that I never bothered trying to understand. Bottom line is once you have a few on the deck, you are fine.
Thank you!
You're welcome!
Can wire screen be substituted for the wire radials, how big of screen or screen sections needed?
Anything works as "radials" - however it's genuinely tough to beat a radial field.
3db is alot when doing DXCC!!
It is a lot.. But the good news, just a few and you've bolted on about 2dB :)
Optiomem, radiation pattern?
&tuned coaxial cable.
@1/4 >< wave,
Check internet since many variables..
no radials , just bunch them up at the base on a heap , works .
Im thinking of a stealth telescopic flagpole antenna at my apartment 2nd story balcony, can i do just some free hanging radials , will it help? Is that sort of like a counterpoise?
One hanging radial will make it into a vertical dipole. Perfect!
Will radials on a slope (hill going up behind antenna) affect the radiation pattern of the antenna?
Good question.. This will answer :) ua-cam.com/video/JZFuOzKY8gg/v-deo.html
Thanks Callum, for getting me interested in amateur radio. Great videos. Question:- Would it be effective if you had a ground spike on the bottom of your antennas? This would make it easier to erect the antenna, but would it effect the radials if you added a ground spike on the DX Commander.
It would do nothing materially to your signal at all other than assisting lightning.. However, if you wanted a little spike to easy of tilting, like a hinge, sure!
How crucial is it to have the radials within the harmonic, that is, wavelength of the band? I always thought the purpose of ground radials was to bond to the earth, not create a counter poise on the ground.
If you are talking about specific lengths, then ignore it. Lengths are not critical at all.
Great Video Cal, 73’s
Thanks for the visit
My buddy N2ewm has a shunt feed vertical 125’ long up the tower insulated from tower. Ran 120 full length 12awg radial and he run 20 over s9 prior he had 60 and about half the output. He also tested at 85-90 radials and was about a 10-15 over s9. I was surprised as I trust the On4un and he say rules of diminishing returns was in the area of 64 🤔🤔??? He vertical works a treat but his 160sky loop at 120’ high produces a 40 over s9 I’m about 200 miles away. He tried NY to SC and was about the same strength on both. Ops forgot to mention he also runs a 10m 4 element Yagi on the tower as a cap hat too how much that help I’m not sure 🤔
Well, I like to keep things easy.. Very difficult to compare like for like etc..
@@DXCommanderHQ no way would I ever well I’m contemplating a vertical like yours and may be a 4” wide copper sheet but in a roll maybe do 16 1/4w as you say. I’m not one who likes extra work but I do strive for best efficiency where I can.
Think my next project is a 8” coil wound inside a 3D printed coil form then a 7’ mast with a spiral cap hat similar to hiQ mobile but bigger coil. I’m contemplating 3/16” copper mandrel bent. Then sun how rigging a plunger roller to make it multi banded but need to hire a cad guy to make the part files to send out for quotes
with 127 radials, you may as well have a huge chequerplate steel plate around the antenna! 😮
Haha yes!
I don't use any radials on a 22ft vertical and with 100 watts talk from Cleveland to South America, Europe, Africa etc. on 15/12/10 meters.
If it's an "end-fed" you won't need any but for 40m, you would need a 20m pole :)
What about installing the DX Commander about two or three meters above ground level with raised radials?
I have installed several home brewed vertical antennas with raised radials and the difference between on the ground radials and just a few raised radials is like night and day. The raised radials are to my ears far superior to several radials on the ground. Several S units higher according to many I have talked to. Received signals are far higher also.
Just got my DX Commander and am thinking about setting it up with raised radials......is that possible and is it a good idea before I put for the effort to put the antenna up?
Everything is possible.. You COULD do it. There are pitfalls.. But I'm sure you'll work it out :)
@@DXCommanderHQ I did it! It works GREAT and only just a few radials . Installed my DX Commander two meters above ground using a fiberglass pole and a piece of wood drilled with a hole in it holding it in position with a band clamp on the fiberglass pole. The pole is held in position with a piece of angle iron pounded three feet into the ground using a fence post hammer and the pole is held in position on the angle iron with a couple of stainless steel band clamps.....very easy. The various length radials are held in position with trees in my back yard using screw eyes and rope.
I liked my DX Commander now I LOVE my DX Commander.
How many Watts can the DX Commander handle? I just need to run a pair of 3-500Z tubes into it
At 14MHz, we tested 1,600W at 65 seconds. Above that and the little loop can get hot so we developed a work-around. Soon to be in the manual (I'm writing a Unified user guide right now!)
So given your dx commander antenna, setup radials for the lowest band? What happen to the upper bands? Measurable difference?
I don’t understand.. This is an experiment.
Can you cut them in half again and add them back in? So basically 1/16 wave.
Yes but eventually they will just be too small. For 80m I was using radials at just over 3m long. That’s SHORT!
@@DXCommanderHQ I’m more or less looking to create temporary radial fields for POTA. I’ve been watching a bunch of videos on the subject. There’s so many theories and opinions that I’ve found. I’m basically looking to use a telescoping 1/4 wave on a ground stake. 40-10m including the WARC bands which aren’t really multiples of anything. Obviously 40m is going to have a loading coil at the bottom. Some say 11.5’ and at least six & some say 3 33’. Almost all say more shorter are better than fewer longer. I’m trying to keep as small of a footprint as possible so passersby don’t trip on them.
Do they need to be tuned? I’m finding mixed theories on that as well. It’s not very feasible to have 4 wavelengths of radial wires for 40m for a POTA operation. I’ve seen some experiments where the SWR increases having too many radials. Can you see how I’m so confused?
Thanks for your wonderful videos Callum. 73 de W2ITG
Hi Callum, what do you think about elevated radials? have you try a comparison between elevated radials and buried radials? Tnx in advance. 73 Mauri
Long, long LONG story.. But no. Only because it's a bit of science that is just too difficult to really get down to - AND a DX Commander would need at least 12 radials, every one would need to be a different length..
@@DXCommanderHQ Tnx
I just purchased the Hustler 4BTV For my 1st ham radio antenna. I also purchased your DX radial ground plate. I decided to mount the antenna approximately 5- 1/2 ft. off ground level. Would 6 or 8 Radials at the approx 45' angle be adequate?? I will primarily be using 20M.. I have the same choice you just described off the edge of my yard next to a large church With a metal roof and a tree, Or in the center of my yard clear of obstacles, Yet in the way of my Yard mowing. Going to wait till Spring time to build
Only 5 feet off ground..? Personally, I wouldn't bother.. Why not go to ground level and lay them on ground... But either would work (ish).
@@DXCommanderHQ I'm just going by the dozens of videos that I've watched on UA-cam from people all over the world, That say if you raise It off the ground about 2 m, You can use less radials a 45゚ angle, And supposably get a better performance. Like I said I'm new to this, That's why I was asking a professional. I talk to a technician at DX engineering And he told me I would only need 2 resonant radials if I raise it 6' off the ground, I do find that statement questionable, But I was thinking more like 6 or 8. (I don't know) I was just looking for some solid advice, Whether it is worth it to string out over 30 radials through my yard On the ground as opposed to only having 6 to 8 to deal with if elevated 6' above the ground.
Thanks , Dan, from Pennsylvania 🇺🇸
@@DXCommanderHQ OK, After reading👉👀👈 the DX engineering manual for this antenna, I decided to go with ground mount with the DX Tilting base assembly To help me get it tuned easier. Gonna be a Raidal wire field day this coming Spring 😁
Thanks for the great info..
question for the ages Callum enough said lol good stuff Callum enjoy your day de W9US
Hi Callum , I know this is the wrong video , did you make that CB 1/4 wave ground plane you had planned for use with your 18 meter pole ?
I just started assembling it today.. However, I have promised a few things I *MUST* get done before any more builds.. The new Unified User Guide for our own products (I'm editing that tonight and just taking a break for a moment) and also our new Website. Needs a final push. AFter that, I can go "play" again!
@@DXCommanderHQ You might have to bleep a few QSO , the last time I was on CB radio there was some terrible language lol , people playing music over you it was mayhem ha ha , prob all quite now though , still be interesting to see the DX on the thing …thanks for the reply ..I remember a girl on there her handle was martini , anytime any place anywhere lol , 73 MW7ANT.
nice 1 cal radials make sense and bring db gain
hmm...i wonder if you keep going if you'll eventually hit euler's number. aka the number 'e'. :P
We shall see
I have 18 of them 3m long and hearing the whole world 👍
Fab!
I think for some of us hams, ROI factors in sooner than diminishing returns. But hey, if you have a fat wallet and you want to be able to brag about having the most bananas, go for it.
Why not simply use some Faraday cloth vs trying to lay out a bunch of radials...simple to lay out and easy to pick up when the wife complains or you need to.dig a trench through your radial field.
OK, you do that .. Happy days.