DX Commander, king of the Radial. I've put 1000 feet (304.8M) of wire down for my vertical on 55 radials. I basically just cut them to fit the space, some as short as 8 feet long, some upwards of 33 feet long, and that is almost 4 wavelengths at 80M (actually it's a full 4 wavelengths on the phone portion of 80M) and stopped putting radials down when I ran out of wires. It was because of videos like this and your others, that I learned that "good enough" is actually VERY good enough. Not gonna miss 1dB of signal.
Thank you for being practical. I'm still new at this and tend to get tangled in details and imaginary perfection. Watching the "manual labor" part of this was a nice trip back home. As a guitarist and former soundman, so many instant repairs were required on the spot. There is something pleasant about making stuff work. I enjoy your videos and always discover something new.
Great video, I have shied away from vertical’s with radials do to my garden size, you have just taken away that fear of trying one, using shorter radials with no substantial loss is a BIG WIN for me. Now to get off my can and order one Thanks
Good video. Simple wire antennas has always given me a lot of joy. I have made lots of antennas of what my friends call the "WET-vertical" and we used it on multiple IOTA and DX-expeditions with good results. All you need is wire, some string and an SO-239 (female coax connector). These antennas have been used mostly on 160/80/40 as I live in the city and have a small yard I tend to work the lower bands at my summer house (cottage) in the country. I usually use pine trees to hang my wire vertical from. On 40 and 80 it is possible to get the full height but not on 160, There i will simply let the radiating wire lean over the top of the tree and slant to the side downwards. It becomes a "slanting inverted-L" One could also use plastic masts from example spiderbeam or if one wants to go on a budget, fishing poles work great on 20m and up. Good results for me is working more than 150 DXCC on 40m over a weekend, 180+ DXCC on 80m and doing 160m DXCC in less than a year. Usually I will get 50-65 countries on 160m during a major contest weekend. Forgot to mention, that is barefoot.
Excellent results. Excellent designs and deployment of wire antennas. Kudos! I am now trying for 100 countries on HALF wat with my wire antennas. The quest has slowed but I am at 69 countries so far. The quest will continue, it is very FUN. 73
Callum, crimping is mostly for mechanical stress relief and electrical connectivity. But soldering gives you the best connectivity and encapsulates the wire conductors within the solder connection. Minimize you soldering iron contact, and use rosin code flux to accelerate your heat transfer. Best to solder (as you did) and not rely on the crimp. 73 de KD6UYK (Tim).
I was getting all excited about this DX Commander - until I watched multiple videos showing the guys stringing LONG lines of radials. I have just enough room for the Commander, but very limited space to stretch out radials. Especially at even lengths. Your video here shows how the antenna should still work even if only done in a 180° (or even 90º!) spread. This gives me hope that I might be able to make this antenna work for me in my backyard (garden to you UK folks - ha). I've learned to love your informative videos. I've only been into HF for about two months so I'm soaking up as much info as I can.
A good piece of revision for me to see this video again. I'll be doing this in a few weeks when my ground has dried out. Hopefully you will be able to do your radial experiments now in the new place.
Most of my radials are ~62 feet long, and when I tried putting multiple radials on one connector all it did was make laying and stretching them a nightmare of entanglement. After that I just painstakingly added each radial one at a time with its own ring to the bolt. On retrospect, my radial field is over kill, 40 some of those 62 foot radials plus a whole mess of 30 foot radials, on very good conductive soil. Then again, my Hustler 6 is a sledgehammer on every band I use it on with 200 watts barefoot.
Broadcasters here in the US almost fanatically belive in the pioneering 1930s RCA vertical antenna research. Basically, two things are going on at the bottom of a vertical radiator. It has RF current from the coax pushed through it to create the "radiated" electric and magnetic fields. The current varies over the height of vertical element but if it's 1/4 wavelength high (or short but made to look like it's 1/4 wavelength with a loading coil, etc., or otherwise pretending to be a 1/4 wavelength) the current is maximum at the bottom. The ground, connected to the coax shield, also has current flowing through it (opposite polarity) -- a maximum closest to the vertical element. With all this current in the ground near the vertical element it's a good idea for the ground there to have low resistance. Broadcasters put a "screen" or wire mesh from the antenna out a few feet. When an amateur puts down lots of radials he/she makes the area close-in dense with copper--with the same effect as the screen/copper mesh. Current in the ground (radial) system travels along the radials away from (and back to) the bottom of the antenna. Broadcasters "fool" that current into thinking it's feeding a low resistance by making the ground radials (which carry most of that current) 1/4 wavelength long. That's a magic number. Looking into an un-terminated 1/4 wave line, the near end looks Ike the inverse of the impedance at the far end---the inverse of an open circuit (which is theoretically a short)---a low impedence at the near end. Ground wires of any length other than odd multiples of 1/4 wave will behave like a higher resistance ( and complex impedance) than the magic 1/4 wave radials. They tend to lower the current in the whole antenna. So always TRY to (1) have dense copper surrounding a vertical antenna and (2) have "many" radials, each one as close to 1/4 wave long as practical. US
Callum, dare I say, if you stick a nail on that 3m mark you could double your line back, and safe yourself a few trips. (Then on the return, just half the wire at the nail, boom 2 trips 4 wires. ? I helped? I do systems.
I purchase 250 foot rolls of brown colored lamp cord for my radials cut to 16' and then split for two radials, I double this to create four radials per connector (crimped and soldered per Callum's video). I have 48 radials for the permanent multib-band vertical and additional set of 32 x 16' radials and two sets of 16 x 16' radial for portable operation. For the portable radials I use anderson powerpole connectors for very quick deploy of either multiband vertical set up or fast monoband config or when setting up a quick parasitic 10, 12, 15 17, and 20m 2 element array. For faster deploy for the multiband portible I have a radial plate with 32 x 16' radial attached with the radial bundles coiled with velco straps for faster deployment
Very nice video. I’m brand spanking new to HAM. I love your content, it’s really helped me get my head around antennas. I’d love to pick your brain sometime!
Thank you for reply, I was too lazy to put individual radials. Also it was easier to lay out the radial(?) and roll up at the end of field day. One day some one will be able to tell me if there is any effect. Hey it works. Informative video Thank you John ZL4RO
Not totally on-topic but I'm jealous of your new Workshop, and it's great to see another experienced engineer using blunt side-cutters to soft-crimp generic motor connectors (rather than using the rubbish 2 quid tools). And then soldering - just enough so the solder flows through the crimp. Looks easy on video, but try teaching students that skill! Good to "meet" you on here Callum, and I look forward to watching more. Channels like this are appreciated by Hams across the globe. Regards and 73 de Peter G6EPN
Yes indeed you make it look easy. It IS easy, after a few thousand times you do it - right? I can usually do that kind of soldering, but it comes after some voluminous self-training (after initial blunders). Ha!
Just discovered your videos on UA-cam. Excellent, and extremely informative and helpful to my understanding of the hobby. I’ve got my license here in the states but no equipment. 🤣🤣 Thank you.
Nice! Doesn't matter if that rusts a bit because it's TX only.. I heard about the guy who did that with chicken mesh and after three years could hardly hear anything!
Thx. Running a Hustler 4BTV with 32 radials to date , ground current still climbing , I have equipment to measure this rf current. , Proof that more radials are better. Many say at above like 50 radials I will get less and less advantages in lower ground losses. Commercial broadcasters use up to 120 radials to get ground losses very low. When I first put up the hustler I used only 2 radials. ( Because I was in a hurry to try out my new antenna ). It was crap compared to now!!! I could tell,. Many tries calling DX, many so so and fair signal reports. Now. WAY different !!! You NEED radials. Period.
When I added the 80 inverted L I layed down 42 10 foot radials. which puts me at 1.6 wave lengths of wire on the ground for 80. In MMANA the extra wire does show useful improvements on the higher freq bands in the low end of the take off angle.
Cal LOVED the music my friend very nice .saving my money to get one of the RD COMMANDERS. got to figure out which one. Portable or at the QTH, semi permanent. That's one I must figure out . Probably use need the 40 - 10. I have a metal building very close by you think I will have a problem with that. As far as transmission and receiving. 73 my friend de KN4CBS
I have 28 at 5 meters each= 140 meters. Doing well, Longest contact 10,800 miles on my DX Commander Classic. For the fun of it, I am doubling it to see the outcome. :-)
Hi Calum, thanks for restoring some videos, are you able to restore som of the antenna design videos? It was on my list to start with that. Regards. PD1MV
I already have 48 videos uploaded and another 50 or so in the pipe and will release one-a-day.. Also check my Playlists. Some of the ones NOT yet released are available on Playlists.. Then we will start re-making the older ones.. In the meantime, they are still all available over at Odysee (. com). SOme of the very old ones though, although the content was pretty good, I didn't get to the point quick enough..
Thank you for this video Callum. I can’t wait to get my DX Commander Signature that I just ordered. I have to ask though, what song was that around the 17 minute mark? I liked it a lot.
hello Callum, i,m thinking of buying the sig 9 version to replace my hf vertical , i have a 125 ft efhw for top and harmonics for the other bands i made it witha9.1 balun, it works very well and it'll stay up as a back up ant. I'm interested in the sig 9 as it does need guy wires i would be able to get out approx 8 radials, hows about 1 1/4 for each band would that be enough, can you drive a copper earthing rod in the ground and run an earth to that would it act as a counterpoise? or is it not needed, many thanks GW4
Mike.. Honestly, just lay down a load of small radials.. Don't both with earthing rod.. That won't assist.. It's the return currents.. If you are concerned, just remember "small and lots"..
S9o when you have a DX commander antenna that covers mant frequencies do you only make the radials cut to the lowest band , lets say 80m or do you need 80m which covers 40 (20m radials or equivalent ) then 20 which covers 15 (5m radials or equivalent ) then 17 that gets 12m, then 10m which would be 2.5m radials. What do you do when there are multiple bands involved? Cover the lowest or each band with its own radials that also covers the next highest harmonically related band? 80 gets 80 skips 60 but gives you 40 ect. OK fund the answer below, just cut them to the lowest band covered by the antenna. I'll try to go for 32 20 meter radials.
OK, so think lower bands.. Let's say we get 40m just right.. So 16 x 1/4 wave. Or maybe 32 x 1/8 wave. Then all higher frequencies are covered anyway and in this case, 80m will be marginally down (actually, only about 1/4 of dB down) because it will have equiv of having 8 x radials.
Well done for helping Raisa. Just a quick question. Does the diameter of the wire matter for the radials ? I have been using a vertical with a few radials and they are all very thin (cannot remember the AWG now). Thanks and 73''s. Marcelo ZL1MTO
WHAT is the gauge size of your wire in the roll??? it looks quite small and it has plastic cover over it??? thanks fo the info, you know that on certain old barn you will see sheet metal about 36x120 inch long for the roof and i saw some guy taking one of these sheet and buried it in the ground so it would be the ground for their verticals,,is it good? 73 du Quebec Gervais ,ve2ckn
Q: I ve got an full metal/tin double garage and was thinking of using it's roof and walls instead of radials. Would that be eaven remotely efficient? Any difference how it would work on HF, UHF, VHF?
There is a dutch contester that has a 1/4-wave vertical on his shop roof doing exactly what you are talking about. Cant remember his call now but he is usually the strongest dutch station I can hear on 40m. Now, metal roofs are made of pieces of squares, I dont know if the paint or whatever they are covered in insulates but perhaps they can all be interconnected. 73
sorry cal, I got confused. you made a profound statement a few times: "were only talking about 3dB". That is 3db between a bunch of radials and what? an unterminated weave? Thanks! love the videos!
Actually, most of the time, it's not even 3dB.. ALlow me to correct your confusion again when I do another video on radials.. Basically, don't be worried about numbers or lengths. They'll all work.
Hi mate, I just bought the DX Commander Classic. Would there be a problem if I install the antenna on a sloped tiled roof and connect the radials to the roof rain gutters using them as a counterpoise?
Hi callum, I have still to erect my DX Commander i purchased from you but will i need to do 2-4 wavelenths for each band the antanna does at the relative lenths. does that make sense eg if i have 20, 40 and 10 then i will need 4 wavelenght radials for each etc
Hi Callum. Do you know if a robot lawnmower will work if I bury it's navigation wires and leave my radials where they are? And will it affect the antenna?
I wrote to the manufacturer asking about how tight their 820kHz signal is and does it produce any harmonics. That was my ONLY worry. Worst case scenario if switch it off when operating. Else all good.
@@DXCommanderHQ Yes I would imagine that its safest to never have them both switched on at the same time. If I see the robot trying to seduce my DxCommander I will know something is wrong :) Thanks for your reply Callum.
Thanks for your videos. Very informative. I just got into the hobby and got my license. I do have a question about radials. Can you extend an existing radial with a wire nut, soldering or some other method? Would it be better to just run a new wire for the new desired length?
Seeing is believing but on the other hand, Rudy's reputation is several perentage points above mine. If you want "seeing is believing, you need to do it yourself : )
Cal, QUESTION you may have addressed. I am looking at 2 things: for DX C Signature compared to a shortened vertical, what's the pattern difference especially on 40/80m? You may already have done this on your modeling video but I don't see it. Maybe a future topic?? De WO8USA🇺🇸🇺🇸🇺🇸
Yes.. Dr George Brown discovered that for SHORT radiators, 120 was optimum - but as Rudy Severns (and me) discovered, for pure quarter waves, 16 is good, 32 is maybe an overkill..
1st Glad to see back on the air so to speak! So say for your any one of your multi-band verticals, Do you make the the radials based on say the 40m band or 10m band or ??
@@DXCommanderHQ That is HE answer I needed. I was thinking I needed to cut them for 1/4 of 80 then 1/4 of 20 lets say. I thought I needed to cut radials to cover each of the individual vertical wires covering each band on the antenna (but not the harmonically related band that is a freebee). I see I dont need to do all of that.
Question: what would be the effect of water gets in the far end of the radials? Would it make sense to touch each open end with some CA or a thin silicone (or even petroleum jelly like you use on your SO connectors?)
So basically. A quarter wave vertical with 16 quarter length radials, in a circle. Basically a flat satellite dish. So I have both the MFJ1979 and the MP1C antennas. I want to work 40m, which would be 33ft for a 1/4. I would need 16 to get that gain. Using those same radials, I could use it on other bands that have shorter radials. Instead of having radials for 20m, I could use the radials for 40m and have +/- the db?
Yes Andre. OR you could cut ALL those radials in half and add them back in to give you 32 1/8 wave. And of course on 20m, that would give you 32 1/4 wave and on 10m that's 32 full wavelength.. You are correct.
In the main you can... Now, I have not done this experiment - but others have (undocumented apart from some nice emails). I think it depends on quality of ground under the system and a few other fun facts that we don't understand. BUT it's a bit like putting a mag-mount for VHF on the car roof..
@@arekjot4771from what I have seen and read from DXC it’s about total length of wire down, not a specific pattern or length. See the parts where he mentions working out of a 90 degree or 180 degree position.
I saw a guy tuning his radio to 40 meters with a wolf river coil. Initially using a bunch of 16’ radials. Best he got was around 2.0 SWR. He then added 33’ radials one at a time. 40 was looking better. Once he got to 4 33’ radials 40 was practically flat. Just saying.
You are mistaking a coil driven element for a pure 1/4 wave. The two are very different as pointed out in the paper by Dr George Brown 100 years ago. Shortened verticals need MUCH more of a ground plane to compensate for the losses. Even then, they never work as well. Just saying.
I don't know.. We have two benches (two units) the nice plastic grey stuff was made for my by a local company.. The other one is called "Farm Grey" paint! LOL
I'm one of those broadcast engineers who cringe.... :) For AM BCB, the most common configuration is 120 1/4 wave radials (1 every 3 degrees). They're usually buried, a foot or so. At the station where I worked, many of the radials were exposed, due to soil erosion, over the years.
Haha.. Do the math. You were conned! Unless its not a full q/wave. Then 120 is important. See Dr Brown's research. Shorter than full q/wave means more radials.
@@DXCommanderHQ 120 1/4 wave radials is the standard. I don't know why that particular number was adopted. The station I worked for was on 1550 KHz. But the University that owned it had received it as a donation (I guess there IS a Santa Claus), and its original frequency had been 590 KHz. So those radials were 400 ft long. That would be an 800 ft circle, on the property! But they cheated. The radials went under the fence, into the surrounding desert9which was public land).
Radials have always been an interesting discussicion, I gave up on the lengths bit. I use this for a 40M 1/4 wave ground mounted verticle, for field day. I have a reel of 1mm transformer wire, collected over the years. I guess could be up to a kilometer in length all the joints soldered. I attach to the insulator base earth point. start at the antenna, go out 1/4 wave length across about 1/2 meter pegging at each bend and back to and around the insulator at the base of the mast. the mast,, radials start looking like a maltese cross and then fill in the empty spaces, same way. Looks pretty and works very well for the range required. Takes time to put them all out. Have to watch some plonker does not drive over it with his car.@#$%. Your thoughts?? Dud Charmers used to say a 1/4 w circular disc of copper sheet was the perfect earth system. wouldn,t want to foot the bill for that.
John, you would probably find that you could half the radial length and scatter them out and not see any difference. Actually, I am unsure what the impact is of connecting the ends in one continuous "loop".. But if it were me, for my "Once-per-year" outing like this, I would go with 30 x 5m radials and an easy-to-handle wire, connecting 4 radials per connector (because 4 is easy to lay out with human hands) and scatter them out as best I could... Works for me.
If you do them 180 degrees, you'll have a very asymmetric radiation pattern, I've actually tested this. You might actually WANT this if you are only transmitting one direction and trying to block noise from the other.
Yes that is worth considering. I operate on a net where I am trying to get contacts from the west of me. Slight advantage could be helpful, so the layout of the radial field could be designed for best result.
Lighting hit my house last weds night I lost my Ftdx101 two Kenwood 570”s my power supply a Ft 8800 and the 7300 and my AL80B and off center dipole, now I’m fighting my insurance company for the claim, I was looking at your antenna as a replacement but the insurance company is dragging that bloody butts, 73”s from Kg4Muk
Now wait a second. If you think that a 3db loss is insignificant, I totally disagree, That's half your power. Sometimes a small increase in power can make a big difference in understand ability..
Sometimes 3dB can make all the difference.. I have been after an extra 3dB on receive last 12-months! However, I would say 95% of the time, nobody would know.
Turn up the volume :) (seriously, I have an automated audio level plug in called Broadcast Compressor which should keep most of the talking just fine.. I turn down the volume for power tools though!)
Not yet.. That's about 5,000 installations and nobody has that one. Also, I've vever seen it myself. How strange. Mind you, all the copper is glue lined heat-shrink. Helps.
Best to put down a wholly inadequate number of radials so that when your partner is about to issue you with more jobs around the house you can sneak out to the garden and fit more radials...works for me...
Chicken wire anyone??????? Do hams really want to surround their verticals with all the junk around their antenna. I still like 1/2 wl antennas up at least 30 to 40 ft. The current popularity of efhw antennas is giving new life to antenna construction. But there are many ways to drive them other than the lossy 49:1 transformers. BTW, 3 db is half your power if you have forgotten.
Adding 3dB is double - oh, you knew that all along LOL! PS You can't see my radials. I installed them when the grass stopped growing too. Multibanding an end fed from 40m and up is a bit of an ask.. By all means send me a design though..
@@DXCommanderHQ Put .05 wl of wire after the 1/2 wire (at lowest freq.) and feed between them with an antenna tuner. (tuner can be balanced to ground but floating outputs work a little better) Works well and no hot transformers. Hams like auto everything. They are getting more lazy every day.
@@rickeaston3228 Oh well, you can feed anything with a tuner :) My old SG230 did everything. Best cheat there was. Worked fantastic too! Taught me nothing as well :)
@@DXCommanderHQ You can feed anything with the right transformer too. The point is that a 1/2 wl antenna has advantages over center fed dipoles. The feed method isn't what is important.
This man knows his stuff used his ideas to do my radial field and have talked all over the world 👍👍👍. Thanks mate.
No problem 👍
DX Commander, king of the Radial. I've put 1000 feet (304.8M) of wire down for my vertical on 55 radials. I basically just cut them to fit the space, some as short as 8 feet long, some upwards of 33 feet long, and that is almost 4 wavelengths at 80M (actually it's a full 4 wavelengths on the phone portion of 80M) and stopped putting radials down when I ran out of wires. It was because of videos like this and your others, that I learned that "good enough" is actually VERY good enough. Not gonna miss 1dB of signal.
You are spot on...
Read Chapters 9 & 10 of W1ZY's book for more info about this topic. You did the right thing.
Put my classic up today here in west Virginia and I'm truly amazed how easy it was and the tuning was spot on.. love my antenna!
Good man! Don't forget an eHam review! Yeah :)
Was just in Weston the other day. Beautiful state!
Thank you for being practical. I'm still new at this and tend to get tangled in details and imaginary perfection. Watching the "manual labor" part of this was a nice trip back home. As a guitarist and former soundman, so many instant repairs were required on the spot. There is something pleasant about making stuff work. I enjoy your videos and always discover something new.
Lovely comment. Thank YOU!
Great video, I have shied away from vertical’s with radials do to my garden size, you have just taken away that fear of trying one, using shorter radials with no substantial loss is a BIG WIN for me.
Now to get off my can and order one
Thanks
Brilliant!
That trick works great for wrapping extension cords as well. I always remember it as "OVER-worked, UNDER-paid" as I'm wrapping. Helps me keep rhythm.
Great tip!
Good video. Simple wire antennas has always given me a lot of joy.
I have made lots of antennas of what my friends call the "WET-vertical" and we used it on multiple IOTA and DX-expeditions with good results.
All you need is wire, some string and an SO-239 (female coax connector). These antennas have been used mostly on 160/80/40 as I live in the city and have a small yard I tend to work the lower bands at my summer house (cottage) in the country.
I usually use pine trees to hang my wire vertical from. On 40 and 80 it is possible to get the full height but not on 160, There i will simply let the radiating wire lean over the top of the tree and slant to the side downwards. It becomes a "slanting inverted-L"
One could also use plastic masts from example spiderbeam or if one wants to go on a budget, fishing poles work great on 20m and up.
Good results for me is working more than 150 DXCC on 40m over a weekend, 180+ DXCC on 80m and doing 160m DXCC in less than a year.
Usually I will get 50-65 countries on 160m during a major contest weekend. Forgot to mention, that is barefoot.
Yeah, 100+ over a weekend is always good fun!
@@DXCommanderHQ And all possible by a little wire.
Excellent results. Excellent designs and deployment of wire antennas. Kudos! I am now trying for 100 countries on HALF wat with my wire antennas. The quest has slowed but I am at 69 countries so far. The quest will continue, it is very FUN. 73
Uncle Roly is an true Expert. 💯👏👍🙋♂
You got that right!
Callum, crimping is mostly for mechanical stress relief and electrical connectivity. But soldering gives you the best connectivity and encapsulates the wire conductors within the solder connection. Minimize you soldering iron contact, and use rosin code flux to accelerate your heat transfer. Best to solder (as you did) and not rely on the crimp. 73 de KD6UYK (Tim).
Well, for spacecraft and stuff that vibrates, then sure so whatever.. But for radials, who cares! LOL
I was getting all excited about this DX Commander - until I watched multiple videos showing the guys stringing LONG lines of radials. I have just enough room for the Commander, but very limited space to stretch out radials. Especially at even lengths. Your video here shows how the antenna should still work even if only done in a 180° (or even 90º!) spread. This gives me hope that I might be able to make this antenna work for me in my backyard (garden to you UK folks - ha). I've learned to love your informative videos. I've only been into HF for about two months so I'm soaking up as much info as I can.
It'll work. Don't worry.
Plenty of 100W USA stations last night getting through.
A good piece of revision for me to see this video again. I'll be doing this in a few weeks when my ground has dried out. Hopefully you will be able to do your radial experiments now in the new place.
Most of my radials are ~62 feet long, and when I tried putting multiple radials on one connector all it did was make laying and stretching them a nightmare of entanglement. After that I just painstakingly added each radial one at a time with its own ring to the bolt. On retrospect, my radial field is over kill, 40 some of those 62 foot radials plus a whole mess of 30 foot radials, on very good conductive soil.
Then again, my Hustler 6 is a sledgehammer on every band I use it on with 200 watts barefoot.
Knuju
Broadcasters here in the US almost fanatically belive in the pioneering 1930s RCA vertical antenna research.
Basically, two things are going on at the bottom of a vertical radiator. It has RF current from the coax pushed through it to create the "radiated" electric and magnetic fields. The current varies over the height of vertical element but if it's 1/4 wavelength high (or short but made to look like it's 1/4 wavelength with a loading coil, etc., or otherwise pretending to be a 1/4 wavelength) the current is maximum at the bottom. The ground, connected to the coax shield, also has current flowing through it (opposite polarity) -- a maximum closest to the vertical element. With all this current in the ground near the vertical element it's a good idea for the ground there to have low resistance. Broadcasters put a "screen" or wire mesh from the antenna out a few feet. When an amateur puts down lots of radials he/she makes the area close-in dense with copper--with the same effect as the screen/copper mesh. Current in the ground (radial) system travels along the radials away from (and back to) the bottom of the antenna. Broadcasters "fool" that current into thinking it's feeding a low resistance by making the ground radials (which carry most of that current) 1/4 wavelength long. That's a magic number. Looking into an un-terminated 1/4 wave line, the near end looks Ike the inverse of the impedance at the far end---the inverse of an open circuit (which is theoretically a short)---a low impedence at the near end. Ground wires of any length other than odd multiples of 1/4 wave will behave like a higher resistance ( and complex impedance) than the magic 1/4 wave radials. They tend to lower the current in the whole antenna. So always TRY to (1) have dense copper surrounding a vertical antenna and (2) have "many" radials, each one as close to 1/4 wave long as practical.
US
Interesting.
Callum, dare I say, if you stick a nail on that 3m mark you could double your line back, and safe yourself a few trips. (Then on the return, just half the wire at the nail, boom 2 trips 4 wires. ? I helped? I do systems.
Love this video. I think you had it on your old channel, but it's such a great video that I watched it all over again. Great information!
Sweet Georgia Brown
@@hamradiotube Jesus Cheeses
I purchase 250 foot rolls of brown colored lamp cord for my radials cut to 16' and then split for two radials, I double this to create four radials per connector (crimped and soldered per Callum's video). I have 48 radials for the permanent multib-band vertical and additional set of 32 x 16' radials and two sets of 16 x 16' radial for portable operation. For the portable radials I use anderson powerpole connectors for very quick deploy of either multiband vertical set up or fast monoband config or when setting up a quick parasitic 10, 12, 15 17, and 20m 2 element array. For faster deploy for the multiband portible I have a radial plate with 32 x 16' radial attached with the radial bundles coiled with velco straps for faster deployment
Like the parasitic style!
Very nice video. I’m brand spanking new to HAM. I love your content, it’s really helped me get my head around antennas. I’d love to pick your brain sometime!
Yes OK!
Thank you for reply, I was too lazy to put individual radials. Also it was easier to lay out the radial(?) and roll up at the end of field day. One day some one will be able to tell me if there is any effect. Hey it works. Informative video Thank you John ZL4RO
Absolutely.. If it works :)
Not totally on-topic but I'm jealous of your new Workshop, and it's great to see another experienced engineer using blunt side-cutters to soft-crimp generic motor connectors (rather than using the rubbish 2 quid tools). And then soldering - just enough so the solder flows through the crimp. Looks easy on video, but try teaching students that skill! Good to "meet" you on here Callum, and I look forward to watching more. Channels like this are appreciated by Hams across the globe. Regards and 73 de Peter G6EPN
Hello Peter, you sound a great guy. Like it! Welcome :)
Yes indeed you make it look easy. It IS easy, after a few thousand times you do it - right? I can usually do that kind of soldering, but it comes after some voluminous self-training (after initial blunders). Ha!
Well that simplified the radials . Great info . Will be waiting for next video .:) good day Callum
Thanks 👍
Just discovered your videos on UA-cam. Excellent, and extremely informative and helpful to my understanding of the hobby. I’ve got my license here in the states but no equipment. 🤣🤣 Thank you.
No gear.. OK. You can listen on some webSDRs maybe..
An AM station nearby built a new tower and placed wire mesh under a parking lot and office building it really worked well.
Nice! Doesn't matter if that rusts a bit because it's TX only.. I heard about the guy who did that with chicken mesh and after three years could hardly hear anything!
@@DXCommanderHQ All the junctions were welded, at the time in the 80s it was a pretty big deal, they are still using the site.
@@DXCommanderHQ Wonder if the transmissions mess up the onboard computers of the cars.
Thx. Running a Hustler 4BTV with 32 radials to date , ground current still climbing , I have equipment to measure this rf current. , Proof that more radials are better. Many say at above like 50 radials I will get less and less advantages in lower ground losses. Commercial broadcasters use up to 120 radials to get ground losses very low. When I first put up the hustler I used only 2 radials. ( Because I was in a hurry to try out my new antenna ). It was crap compared to now!!! I could tell,. Many tries calling DX, many so so and fair signal reports. Now. WAY different !!! You NEED radials. Period.
You do need radials.. But from 16 to 64, there's less than 1.5dB. UNLESS you have some really crappy ground.
When I added the 80 inverted L I layed down 42 10 foot radials. which puts me at 1.6 wave lengths of wire on the ground for 80. In MMANA the extra wire does show useful improvements on the higher freq bands in the low end of the take off angle.
Well spotted.. and good work!
Cal LOVED the music my friend very nice .saving my money to get one of the RD COMMANDERS. got to figure out which one. Portable or at the QTH, semi permanent. That's one I must figure out . Probably use need the 40 - 10. I have a metal building very close by you think I will have a problem with that. As far as transmission and receiving.
73 my friend
de KN4CBS
You will be surprised with the metal building. It's never as bad as we think.. Erm.. Possibly aim for the DXC Expedition. Lovely antenna.
I have 28 at 5 meters each= 140 meters. Doing well, Longest contact 10,800 miles on my DX Commander Classic. For the fun of it, I am doubling it to see the outcome. :-)
Oh! What fun!!
Thank you for sharing the truth about antennas, and the awesomeness of vertical ground plane antennas for DXimg. You are a champion. 73. KO6DEV.
Thank you kindly
I only ever use 180 degrees at home and it’s always worked for me with lots of contacts with 32 radials at 2.5m long.
Perfect!
Hi Calum, thanks for restoring some videos, are you able to restore som of the antenna design videos? It was on my list to start with that.
Regards. PD1MV
I already have 48 videos uploaded and another 50 or so in the pipe and will release one-a-day.. Also check my Playlists. Some of the ones NOT yet released are available on Playlists.. Then we will start re-making the older ones.. In the meantime, they are still all available over at Odysee (. com). SOme of the very old ones though, although the content was pretty good, I didn't get to the point quick enough..
Thank you for this video Callum. I can’t wait to get my DX Commander Signature that I just ordered.
I have to ask though, what song was that around the 17 minute mark? I liked it a lot.
Found it! ua-cam.com/video/7jHcszxmKRw/v-deo.html (it's also direct at EpidemicSound.com)
hello Callum, i,m thinking of buying the sig 9 version to replace my hf vertical , i have a 125 ft efhw for top and harmonics for the other bands i made it witha9.1 balun, it works very well and it'll stay up as a back up ant. I'm interested in the sig 9 as it does need guy wires i would be able to get out approx 8 radials, hows about 1 1/4 for each band would that be enough, can you drive a copper earthing rod in the ground and run an earth to that would it act as a counterpoise? or is it not needed, many thanks GW4
Mike.. Honestly, just lay down a load of small radials.. Don't both with earthing rod.. That won't assist.. It's the return currents.. If you are concerned, just remember "small and lots"..
S9o when you have a DX commander antenna that covers mant frequencies do you only make the radials cut to the lowest band , lets say 80m or do you need 80m which covers 40 (20m radials or equivalent ) then 20 which covers 15 (5m radials or equivalent ) then 17 that gets 12m, then 10m which would be 2.5m radials. What do you do when there are multiple bands involved? Cover the lowest or each band with its own radials that also covers the next highest harmonically related band? 80 gets 80 skips 60 but gives you 40 ect.
OK fund the answer below, just cut them to the lowest band covered by the antenna. I'll try to go for 32 20 meter radials.
OK, so think lower bands.. Let's say we get 40m just right.. So 16 x 1/4 wave. Or maybe 32 x 1/8 wave. Then all higher frequencies are covered anyway and in this case, 80m will be marginally down (actually, only about 1/4 of dB down) because it will have equiv of having 8 x radials.
Well done for helping Raisa.
Just a quick question. Does the diameter of the wire matter for the radials ? I have been using a vertical with a few radials and they are all very thin (cannot remember the AWG now). Thanks and 73''s. Marcelo ZL1MTO
Not at all. Thin is fine - right down to individual strands of an ethernet cable - probably thinner!
WHAT is the gauge size of your wire in the roll???
it looks quite small and it has plastic cover over it???
thanks fo the info,
you know that on certain old barn you will see sheet metal about 36x120 inch long for the roof and i saw some guy taking one of these sheet and buried it in the ground so it would be the ground for their verticals,,is it good?
73 du Quebec
Gervais ,ve2ckn
DX10 is 2.4mm and the PVC is extremely specialist..
Q: I ve got an full metal/tin double garage and was thinking of using it's roof and walls instead of radials. Would that be eaven remotely efficient? Any difference how it would work on HF, UHF, VHF?
There is a dutch contester that has a 1/4-wave vertical on his shop roof doing exactly what you are talking about. Cant remember his call now but he is usually the strongest dutch station I can hear on 40m.
Now, metal roofs are made of pieces of squares, I dont know if the paint or whatever they are covered in insulates but perhaps they can all be interconnected. 73
Yes, people have done this.
You could use a hydraulic crimp tool from Harbor Freight (if you have them in England).
Oh yes, I could have a tool for everything. Imagine the storage space :)
sorry cal, I got confused. you made a profound statement a few times: "were only talking about 3dB". That is 3db between a bunch of radials and what? an unterminated weave? Thanks! love the videos!
Actually, most of the time, it's not even 3dB.. ALlow me to correct your confusion again when I do another video on radials.. Basically, don't be worried about numbers or lengths. They'll all work.
Hi mate, I just bought the DX Commander Classic. Would there be a problem if I install the antenna on a sloped tiled roof and connect the radials to the roof rain gutters using them as a counterpoise?
As long as you can EASILY Maintain it and get to it easily - AND it's safe, why not.
Callum what do you think about the Hustler 6btv antenna?
Never had one. Maybe ask on the discord.io/discord server. There are some people that have swapped.
Hi callum, I have still to erect my DX Commander i purchased from you but will i need to do 2-4 wavelenths for each band the antanna does at the relative lenths. does that make sense eg if i have 20, 40 and 10 then i will need 4 wavelenght radials for each etc
Any radials / any length to suit your property / location.
Hi Callum. Do you know if a robot lawnmower will work if I bury it's navigation wires and leave my radials where they are? And will it affect the antenna?
I wrote to the manufacturer asking about how tight their 820kHz signal is and does it produce any harmonics. That was my ONLY worry. Worst case scenario if switch it off when operating. Else all good.
@@DXCommanderHQ Yes I would imagine that its safest to never have them both switched on at the same time. If I see the robot trying to seduce my DxCommander I will know something is wrong :) Thanks for your reply Callum.
Keep it up Cal.
Thanks, will do!
Thanks for your videos. Very informative. I just got into the hobby and got my license. I do have a question about radials. Can you extend an existing radial with a wire nut, soldering or some other method? Would it be better to just run a new wire for the new desired length?
Either/ or. Doesn't matter. More shorter rather than fewer longer.
@@DXCommanderHQ Thank you
At 3:50 -- I hope you put that test onto your To Do list. Seeing is believing.
Seeing is believing but on the other hand, Rudy's reputation is several perentage points above mine. If you want "seeing is believing, you need to do it yourself : )
Cal, QUESTION you may have addressed. I am looking at 2 things: for DX C Signature compared to a shortened vertical, what's the pattern difference especially on 40/80m? You may already have done this on your modeling video but I don't see it. Maybe a future topic?? De WO8USA🇺🇸🇺🇸🇺🇸
OK, so the 12.4m is probably about 1dB down on a HUGE 80m q/wave vertical. The rest of the bands behave as a q/wave.
A little overkill perhaps but in the main well done. The FCC once required 120 radials for commercials. Steve N7VS
Yes.. Dr George Brown discovered that for SHORT radiators, 120 was optimum - but as Rudy Severns (and me) discovered, for pure quarter waves, 16 is good, 32 is maybe an overkill..
I enjoy your videos very much!
Glad you like them!
1st Glad to see back on the air so to speak! So say for your any one of your multi-band verticals, Do you make the the radials based on say the 40m band or 10m band or ??
I base mine on lowest frequency I'm going to use it..
@@DXCommanderHQ That is HE answer I needed. I was thinking I needed to cut them for 1/4 of 80 then 1/4 of 20 lets say. I thought I needed to cut radials to cover each of the individual vertical wires covering each band on the antenna (but not the harmonically related band that is a freebee). I see I dont need to do all of that.
Finally I know , and 180degree will work for me
Question: what would be the effect of water gets in the far end of the radials? Would it make sense to touch each open end with some CA or a thin silicone (or even petroleum jelly like you use on your SO connectors?)
Er.. OK, you will not see any change in your life - but you COULD make little loops and glue-line-heat-shrink them.
Hi Callum, does wire size matter for the radials? Would it be ok to use 24awg for radials?
Yes - just fine.
So basically. A quarter wave vertical with 16 quarter length radials, in a circle. Basically a flat satellite dish.
So I have both the MFJ1979 and the MP1C antennas. I want to work 40m, which would be 33ft for a 1/4. I would need 16 to get that gain. Using those same radials, I could use it on other bands that have shorter radials. Instead of having radials for 20m, I could use the radials for 40m and have +/- the db?
Yes Andre. OR you could cut ALL those radials in half and add them back in to give you 32 1/8 wave. And of course on 20m, that would give you 32 1/4 wave and on 10m that's 32 full wavelength.. You are correct.
Which version of DX Commander is best for permanent installation and covering 10-80 meters?
Ah. I got this one twice. See other comment :)
As always, Gold to watch your videos. 73s
Wow, thanks!
I'm guessing (ideally) if you have a dxcommander which does 40m , then you need 4 x 40m of wire down, 160m radials. 16 x 10m ?
For perfection on 40m, yes. However the difference to putting down half that is not noticable.
I'm jealous of your work bench. I have no place to work and have to make sure my wife is out of the kitchen when I do things like cut radials..
Mike M0MSN is the same :)
You only need 3 or 4 radials. They should be slanted 40 to 45° from vertical for best performance. The antenna can be tilted for talking skip.
Kevin, I believe you have fallen into the myth trap :)
How do radials work for a vertical on my house roof? Can I place them on the roof and let them drape over the rain gutter?
In the main you can... Now, I have not done this experiment - but others have (undocumented apart from some nice emails). I think it depends on quality of ground under the system and a few other fun facts that we don't understand. BUT it's a bit like putting a mag-mount for VHF on the car roof..
Hey, how about 5/8 vertical antenna for 20m band? What should be the lenght of radials and how many of them should I use? Newbie to ham radio here
You can do that but you would need to match it with a small coil.
@@DXCommanderHQ thanks for your answer. But what about radials for 5/8 vertical? Can they be the of the same length as for 1/4 wave?
@@arekjot4771from what I have seen and read from DXC it’s about total length of wire down, not a specific pattern or length. See the parts where he mentions working out of a 90 degree or 180 degree position.
Can you just use the fence (if it is metal) for radials?
COuld do.. Frank;ly nothing beats a good set of real radials.. But everything works..
Client: How many radials do I need? DXC: Yes. 😁
HAHAHA
You waterproof the connector end but what about wicking from the other end?
Modern PL259s SHOULD have a rubber grommit that will seal it up. Not the old crappy dollar for 10.. :)
@@DXCommanderHQ I was talking about the radials. Stranded wire will wick moisture. Over time this wicking may cause issues inside the jacket, I think.
I saw a guy tuning his radio to 40 meters with a wolf river coil. Initially using a bunch of 16’ radials. Best he got was around 2.0 SWR. He then added 33’ radials one at a time. 40 was looking better. Once he got to 4 33’ radials 40 was practically flat. Just saying.
You are mistaking a coil driven element for a pure 1/4 wave. The two are very different as pointed out in the paper by Dr George Brown 100 years ago. Shortened verticals need MUCH more of a ground plane to compensate for the losses. Even then, they never work as well. Just saying.
That's is the way I would make them.
What is the surface material on your work bench? K9RJ
I don't know.. We have two benches (two units) the nice plastic grey stuff was made for my by a local company.. The other one is called "Farm Grey" paint! LOL
I'm one of those broadcast engineers who cringe.... :) For AM BCB, the most common configuration is 120 1/4 wave radials (1 every 3 degrees). They're usually buried, a foot or so. At the station where I worked, many of the radials were exposed, due to soil erosion, over the years.
Haha.. Do the math. You were conned! Unless its not a full q/wave. Then 120 is important. See Dr Brown's research. Shorter than full q/wave means more radials.
@@DXCommanderHQ 120 1/4 wave radials is the standard. I don't know why that particular number was adopted. The station I worked for was on 1550 KHz. But the University that owned it had received it as a donation (I guess there IS a Santa Claus), and its original frequency had been 590 KHz. So those radials were 400 ft long. That would be an 800 ft circle, on the property! But they cheated. The radials went under the fence, into the surrounding desert9which was public land).
great stuff cal!
Appreciate it!
Love this video!!!
Radials have always been an interesting discussicion, I gave up on the lengths bit. I use this for a 40M 1/4 wave ground mounted verticle, for field day. I have a reel of 1mm transformer wire, collected over the years. I guess could be up to a kilometer in length all the joints soldered. I attach to the insulator base earth point. start at the antenna, go out 1/4 wave length across about 1/2 meter pegging at each bend and back to and around the insulator at the base of the mast. the mast,, radials start looking like a maltese cross and then fill in the empty spaces, same way. Looks pretty and works very well for the range required. Takes time to put them all out. Have to watch some plonker does not drive over it with his car.@#$%. Your thoughts?? Dud Charmers used to say a 1/4 w circular disc of copper sheet was the perfect earth system. wouldn,t want to foot the bill for that.
John, you would probably find that you could half the radial length and scatter them out and not see any difference. Actually, I am unsure what the impact is of connecting the ends in one continuous "loop".. But if it were me, for my "Once-per-year" outing like this, I would go with 30 x 5m radials and an easy-to-handle wire, connecting 4 radials per connector (because 4 is easy to lay out with human hands) and scatter them out as best I could... Works for me.
can hi use the fence aswell plz calum
Can do.. I honestly do not know if it's better or worse.. Mine are bonded to the fence..
so is it 5 wavelengths of radials no matter the length of each one?
I would say 4-5 wavelengths.. Try not to go less than about 1/8th wavelength. Saying that, my 80m /P radials are 5% wavelength!
the revealed mystery 24 radials per band fantastic 24 radials 40 meters, 24 radials 20 meters, 24 radials 11mts roe 1,1 spectacular TX RX EC5APA
Yes :)
Thanks!
Welcome!
Callum my favorite bret! Ham harder my friend.
Yo! Big John! (love that handle!!)
0.4 wavelength gives optimum earth for frequency all in total us hams recommend
There is no "optimal". Depends on radiator lengths and numbers. Salt water is even better.. :)
If you do them 180 degrees, you'll have a very asymmetric radiation pattern, I've actually tested this. You might actually WANT this if you are only transmitting one direction and trying to block noise from the other.
Yes that is worth considering. I operate on a net where I am trying to get contacts from the west of me. Slight advantage could be helpful, so the layout of the radial field could be designed for best result.
Fantastic explanation! -W8OKN
Glad it was helpful!
Thank you Sir.
You are most welcome
Lighting hit my house last weds night I lost my Ftdx101 two Kenwood 570”s my power supply a Ft 8800 and the 7300 and my AL80B and off center dipole, now I’m fighting my insurance company for the claim, I was looking at your antenna as a replacement but the insurance company is dragging that bloody butts, 73”s from Kg4Muk
Oh Wayne! I was lucky, my insurance paid out. Good luck.
Is it directional @ 180 or 90 degrees?
Now.. I don't fully understand the question Ed.. So sorry! Feel free to drop me an email (in case I miss your response!)
Nice stripper! You should have an Amazon affiliate link for the tools you use. What is it?
Erm.. I don't know what tool I used sorry.
The best number of radials is determined by your property size.
Now wait a second. If you think that a 3db loss is insignificant, I totally disagree, That's half your power. Sometimes a small increase in power can make a big difference in understand ability..
Sometimes 3dB can make all the difference.. I have been after an extra 3dB on receive last 12-months! However, I would say 95% of the time, nobody would know.
The video's audio levels are a bit low.
Turn up the volume :) (seriously, I have an automated audio level plug in called Broadcast Compressor which should keep most of the talking just fine.. I turn down the volume for power tools though!)
@@DXCommanderHQ Sounds fine to me, on my studio monitors in a treated room. Cheers!
Show any copper and water plus power will rapidly convert them to copper oxide.
Not yet.. That's about 5,000 installations and nobody has that one. Also, I've vever seen it myself. How strange. Mind you, all the copper is glue lined heat-shrink. Helps.
안녕하세요
ever heard of cookin foil?
Oh yes.
Best to put down a wholly inadequate number of radials so that when your partner is about to issue you with more jobs around the house you can sneak out to the garden and fit more radials...works for me...
Brilliant!
Use chicken wire better radial field cheap cheerfully and works
Be careful.. ua-cam.com/video/yvkm9Cf9IO4/v-deo.html
Chicken wire anyone??????? Do hams really want to surround their verticals with all the junk around their antenna. I still like 1/2 wl antennas up at least 30 to 40 ft. The current popularity of efhw antennas is giving new life to antenna construction. But there are many ways to drive them other than the lossy 49:1 transformers.
BTW, 3 db is half your power if you have forgotten.
Adding 3dB is double - oh, you knew that all along LOL! PS You can't see my radials. I installed them when the grass stopped growing too. Multibanding an end fed from 40m and up is a bit of an ask.. By all means send me a design though..
@@DXCommanderHQ Put .05 wl of wire after the 1/2 wire (at lowest freq.) and feed between them with an antenna tuner. (tuner can be balanced to ground but floating outputs work a little better) Works well and no hot transformers. Hams like auto everything. They are getting more lazy every day.
@@rickeaston3228 Oh well, you can feed anything with a tuner :) My old SG230 did everything. Best cheat there was. Worked fantastic too! Taught me nothing as well :)
@@DXCommanderHQ You can feed anything with the right transformer too. The point is that a 1/2 wl antenna has advantages over center fed dipoles. The feed method isn't what is important.
Radiation PATTERN?
Buggered...?
Radiation patterns of verticals on internet.. easy.