How does a DX Commander Work?
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- Опубліковано 26 сер 2024
- The technique is simple but some people still think there must be relays, coils and traps. No. Let me explain. Callum, Founder, DX Commander.
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The DX Commander vertical works the same way a "Fan Dipole" works. Depending on what band the RF you're sending up the feedline is, it "ignores" the non-resonant elements and uses the resonant ones automatically. Without going into reactance and all the tech mumbo jumbo, basically the RF will want to go to the closest elements that present a 50 ohm load to the transmitter.
Easiest way to imagine it is that the RF is like a lightning bolt or arc, It will take the easiest path back to your radio. Pretty cool!
Yeah, when I learned how my fan dipole worked, oh wait and then Add a coil and boom! I learned so much. By the way Callum is an EZNEC wizard 😆
The answer to the question.. the DX Commander works great!
And it works very well indeed, even in my high noise environment I can make contacts I can not make with another antenna. Thanks for putting in all the time and work developing your version of the multi-band vertical. Jack K5FIT
Thanks Jack!
The DX Commander is the best antenna for the money by far!
Works great for me. It's every bit as good as my Hustler 5BTV, which has over 1000 feet of radials in the ground under it. The DX Commander hears just as well, is usually a little quieter, and near as I can tell there is very little difference in TX quality. It seems that I can hear and be heard just as well on either antenna at any given time.
@@Brian424 👍
Building a fan dipole (for 40 and 60 meters) was where I saw how the lengths of the 1/4 wave driven elements change by the band; 20 is essentially twice as long as the 10 meter element, 40 is twice as long as 20 and so on, it also showed, as you did in this video, how higher frequencies can use an element cut for a lower frequency, like the 40 and 15 meter relationship. Building that dipole is what pushed me to buying a DXC.
Hey Bruce - yes like octaves are on a piano!
What a beautiful analogy: square peg in a round hole for the non-matching elements/frequency.
W8BFO here thanks for the video mate - for the record, I have had my trusty DX Commander outside through 3 summers/winters here in West Virginia. It's the dog's bollocks for the money. I even worked the illustrious Callum on 20 meters using just a few hundred bananas. Stay well Cal.. 73s from good ole US of A.
Lovely!
Great explanation Cal. Thanks for all you do. 73
Thank you for the support!
Another good video! Made me wonder how I would explain it:
"Wiggles are like people, they will always look for the easy way out and that's the wire which is cut (resonant) to match their frequency". 😁👍
Love it!!
It was explained to me many years ago that RF, electricity and also water will always take the easiest path, the one with the least restriction, resistance, impedance.
Perfect Ray!
All those things actually take all available paths, proportional to how easy each path is, rather than just the easiest path.
DX COMMANDER ANTENNA IS A GREAT ONE.
Well… it does work! I just got done with the NVQSO party and got 81k points using my classic! Still absolutely love this antenna!!!
Yes Tyler!!
I'm still waiting to make a clever accident. Lol. The thing is, you followed trough and made it a success. 👍😉
Luck and grit.. They go together I guess :)
A swing set (that you played on as a kid) is a pendulum with a natural resonant frequency. When you push (drive) your swing at the 'right' time (i.e. frequency) your swing passenger starts to very easily swing with higher amplitude, because you're forcing, or driving, the system at it's natural resonance. If, on the other hand, you push your swing passenger much less frequently, or much more frequently, you're forcing off the natural resonance, and your day on the swing set quickly comes to an end. Exactly the same math as for your wire but mechanical vs RF electrical system. Basically, what Callum said. ;)
Beautiful!
got to love simple Callum I've heard guys say I can build that on the cheap but they will not have the best fiberglass pole on the market or everything you've put into the DX Commander Thanks for making verticals fast and easy and can't wait for the next new revision you got instore for us maybe the Signature Classic???????? great stuff as always Callum de W9US
Signature "Classic" soon... Hang on..
Once tuned it works very well.
Yes Ed!
Cracking Vid Cal
Thank you Martin!
Not sure if you will see this but I was watching a video by Peter Waters of Waters & Stanson. Anyway he discusses elevated radials vs ground mount radials. I’m curious if you’ve done any real testing, where you elevate a DX Commander about 2-3 meters high and then experiment with elevate radials.
No need. Lucky for us Rudy Severns did all that work for us. Peter only tells you what he's trying to sell anyway! LOL
Nice video Cal - excellent antenna (classic owner). Mark, 2E0MSR
Hey Mark! Trust all is well fella..
Hi Callum, I think I’ll be getting one of your antennas in the near future. But if I have to site it up against the fence and therefore only been able to put radials 180 degrees around the antenna would this be an issue on the efficiency of the antenna. Look forward to hearing from you asap.
Regards
Mark
Mark, no problem.. Watch for Monday's video (tomorrow). I will demonstrate this..
Cheers Callum lol forward to watching it. I’ll be getting in touch with you by email regarding a new antenna.
How Does a DX Commander work? It Works Bloody Well, thank you... just an amazing piece of kit... Video over! just kidding... Great video Cal and an even better antenna!
Thanks 👍
For me it’s a beautiful antenna that works very well. Great job Callum.
WD5ENH
Steve
Thanks 👍
I don’t even need to watch the video, it’s magic. The end. You’re welcome.
Haha. That's funny!
I am really confused, you explained the wiglies but where do the bananas come into this? 😜
Honestly, if you don't know that private joke, I apologise. Just ignore the bananas.. Thanks.
Is there a problem with parasitic coupling with the other wires in the vertical being so close?
No.. However, energy attracted by any other elements is immediately re-radiated as a fan-dipole would.
Ok, what if instead of ground elements you replace them with a 40 meter copper disk about half an inch thick?
What would that do to your gain?
What would that do to the whole RF physics?
Your wallet wouldn't gain, that is for sure ;) Cheers
Making the copper disc more than a few thousands of an inch thick would not help. :-)
Ignoreing the cost, it would be irrelevant. A few ground radials work just fine. Video coming out shortly about this..
K, so follow up question here. I got the commander 9. Instead of putting the base into the ground for the antenna to go onto, I put a fence post into the ground like 3ft (no concrete) and it stands above the ground another 3 ft. I then made and attached the yellow base that usually goes into the ground to a tilt base that is attached to the top 18" of the the fence post. The commander 9 will slide over this tilt, so the base plate will sit at the top of the fence post. My situation is, to do the radials, they will need to go down to the ground about 3 ft to the ground then spread out from there. Will having the radials going down abt 3 ft to the ground from the base plate and then spreading out across the ground interfere with anything on how the radials or antenna work? (Or will having the antenna raised abt 3 feet cause and detrimental effect on the antenna?) My placememt of the antenna needed to go into some landscaping, hence the needed tilt design. This way though i can tilt it down anytime without lifting it off to remove it like is typical for the commander 9. What say you on how this will affect the antenna or radials?
Try it.. I have only put my radials about 30cm / 12-inches above ground but others have reported success..
Wonder how a non-resonant vertical (popular brand with 27ft or 43ft) performs vs a fan vertical like the DX Commander? I suspect the Commander has better take off angles/lobes in the upper bands? (20-10m)
I sustepct too. Also nothing to get "hot", other than maybe the connection points at the end of the elements (under serious QRO).
Have you ever given a roll-up version of a dx commander any thought? As in even more light-weight by hanging it from a tree instead of a fiber mast? Sorry Cal, just brainstorming a bit. 73's from PD1XAN.
You COULD do this with all the bit and leave the pole behind.. The only problem is getting some tangles maybe..
How does the DX Commander function when you have housing around you? I live in a city.
Not a lot. Most of it is fairly transparent to RF
Dumb question, and theoretically speaking, what would happen if you had separate elements for 40 and 15? Would RF on 15 just go to the 15 element, or would it try to split between the 40 and 15 elements?
They would be shared BUT the longer element presents a better match so most of your signal would use longer one.
@@DXCommanderHQ Thanks. I was asking because my 40 meter antenna is a homemade double bazooka dipole and it doesn't seem to work for 15 at all.
A touch off topic for this DX Commander video Callum, but something that I've been meaning to ask for a few years.
I was at my brother's wedding and during the service a radio transmission kept being heard over their speaker system. I can't remember if call signs were being used, so I don't know if it was CB or HAM transmissions being picked up. The Vicar (a real one) told me later that It'd been happening for a while and they hadn't fixed it.
Would it be the length of the speaker wires being resonant with the transmission frequency or their stereo/PA system's feed wires to amp picking it up and then amplifying it or some other magic? I wish I'd known more to ask them what they'd tried to resolve it.
Probably speaker wires. Possibly mic. Ferrites near the amplifier would probably fix it.
@@DXCommanderHQ Cheers Callum.
If it was speaker wires, does that mean you could luckily cut a wire to the correct length, attached to speakers, and pickup a frequency without a powered system and/or receiver? (I clearly don't know much about radio, but RF does interest me somewhat)
@@TheVicar Anything with an amplifier in it is ready made to pick up AM transmissions like CB. The wires don't need to be resonant, just a little RF needs to couple in and the amp will demodulate it and amplify it. I would think the signal is getting into the mic cables rather than the speaker wires. Telephones, computer speakers, amplifiers pretty much anything turns into a receiver. Putting a 0.1uF or 0.01uF filter cap across the inputs often takes care of it.
@@stargazer7644 Many thanks, as I don't know very much about RF. But what you say would match with the fact that it was only happening when the PA was being used for the readings in church.
I must say it was a bit off putting during the service but didn't spoil the day at all.
Cheers!
OK, I saw mentions of something called TV DX and I ended up here as my first stop to understand what exactly TV DX is. My apologies, but my takeaway from this video is that it is some sort of simple antenna that works great. Nonetheless, what do you use these antennas for? I still do not understand what DX is. Thanks!
Hello. It is probably not your thing.. We use these for ham radio. The term "DX" is basically "long distance". It's all about shortwave radio. Thank you for your comment.
@@DXCommanderHQ Thanks for that. My grandfather was big into HAM radio back in the 1970/80s. He had a large antenna mounted on the back of his house. He really enjoyed spending time in his small home office sitting in front of his radio after he retired from the railroads. I have no idea what ended up happening to all of his gear; it has been gone for decades. Again, thanks.
Yeah, that's what we do! LOL
I'm getting ready to erect a 50ft aluminum tower. I had planned to put a mast in that will be 15ft above the tower for a dualband vertical on top, a set of 13 element vertical polarized 2m, then a cross mast with a 17 element vertical and 19 element horizontal 440mhz, then another set of 13 element horizontal 2m, then a 5 element 6m.
I'm brain storming if i could insulate the bottom from ground and shunt feed the tower. Would it possibly resonate at 80m with the beams acting as a compasidence hat?
Also could I add stand-offs at the top for 40, 20,and 10m vertical elements downto the base.... Am I thinking to big or does it sound reasonable?
Yes apparently this can be done - but it's beyond me because I've never looked at it..
@@DXCommanderHQ thank you for your response. Now i just have to play with the coil on my shunt ground
How does it work? Doingy doingies and wiggly wigglies. That's how!
Oh yes!
Ohhhhh... it's about an antenna.
Callum, don't cover your mouth when you speak. Cheers
When you can cure me of Autism and ADHD, I'll consider it.