NEW CHA F-LOOP 2.0 from Chameleon Antenna is NOW AVAILABLE!

Poor troll, spitting venom as usual! I'm so sorry for you and your weak behavior. You can believe whatever you want if you please! Your lack of decorum and childish behavior are exemplary...

 

Does Duffy examine or calculate the effect the proximity of "ground" has on losses in a low-height dipole too? Has anyone ever verified NEC-4 'ground-effects' modeling as well? To be honest in evaluating antenna performance one really needs to specify the environment in which operation is desired. With a low dipole, losses mount on account of E-field (dielectric) losses AND displacement current (resistive dissipation) losses in the ground beneath the antenna. A loop experiences lower reactive 'near-field' E-field losses on account of the "closed" nature of the loop's circuit and the concentration of electric flux *in* the capacitor, as opposed to ALL the space surrounding a dipole (WHICH include lossy "ground" for a low dipole). Simply concentrating on one antenna's performance to the exclusion of factors which adversely affect other antenna is a 'game' one sees quite often. Consider instead the relative trade-offs in losses.

These factors I mention become increasingly important on the low bands, such as 160 meters where it is impossible for 99.9 percent of operators to achieve even 1/4 wavelength spacing above ground. The contrast in loop versus dipole performance at low height has represented itself as quite prominent in my experience with both antenna types on the low bands and in favor of the loops.

 

My error Carl, I thought you might want to see the math. Instead of attacking my math, can you dispute it? What behavoir is weak or childish? I presented a technical reply to yor statements that refuted them.
All I have ever done is ask questions about statements that I saw as questionable. I have never seen a single accurate response to my questions.
I posted ONE time on Julian's YouTube asking for verification of some statements. Instead, of a reply, my post was deleted. I even signed it Thank you.
I have no issue with any other company. And again, I have no financial interest in the W4OP loop.

 

I have NO horse in this race. Just want to point out that before your math 'lesson', you did offend his Intellect... Not a sure way to win someone to your side.

 

I'm not easily offended!! I'm just tired of that none sense egocentric trolling.

 

I agree- and that was a poor decision on my part. Please accept my apology Carl- I mean this sincerely. Perhaps we can agree to disagree, and take this discussion to private email.

Dale W4OP

 

Hi Carl,
You are not using Steve's calculator correctly. In the "Added Loss Resistance" field you HAVE to add in a value of resistance until the calculated field "Bandwidth" matches the measured 2.62:1 bandwidth of your antenna. If you do not do this, then the calculator assumes your mechanical connections are perfect- that is zero resistance and that your capacitor has infinite Q- an impossible situation. Why Steve made the 2.62:1 (-3dB) field a dependent variable instead of an independent variable only Steve can say.

Dale W4OP

 

After watching this spectacle, I'd never buy anything from either of you.

 

As a relatively new ham this kind of stuff has been frustrating to me. You're not sure who you can believe and I'm not one of those people that's sent stuff to test and review so I have to rely on what I can see or read on the web and we all know that "if it's on the internet, it must be true". Actually you can often see through certain reviews but nothing can replace actually using an item.

After discovering that the quality of materials in the Chameleon appeared to be significantly better than the Alpha along with Chameleon offering the power compensator, I bought the Chameleon. When I received the Chameleon it was definitely the better constructed antenna along with better quality accessiories so I sold off the Alpha and took a partial loss.

In Alpha's defense I will say that while I owned the Alpha I made 38 or 39 QRP contacts in the short part of an afternoon during the NC QSO Party but the contacts weren't that far away. Even still, they were successful contacts.

At this time I haven't used the Chameleon long enough or under the same band conditions to form an opinion of it as far as being able to have a similar day like I had with the Alpha. As we all know, QRP can be tricky. I've made some contacts with the Chameleon all but one time that I set it up so I'm hopeful that I made the right choice between at least those two manufacturers.

After researching mutliband portable verticals I feel like I'm caught in the same pi$$ing contest as what's happening with the loops so I've kind of come to the conclusion that my $20 MFJ Hamtennas that I've tuned to the middle of the band and I've talked all over the world from my mobile appear to be the safest bet for now. I can't picture myself buying the Alpha after seeing their current construction and real world reviews. At this time I can't say I'm ready to buy another Chameleon product until I see how things play out with the loop. That's not a negative comment towards Chameleon, I'm just being practical.

 

Thanks for your reply Dale
First I have to say I don't like the marketing brouhaha either, regardless of who it comes from. I've said this to Carl and other companies of employing this method of promotion in amateur radio. The difference is I usually do it quietly, in a private discussion.
Dale, should we understand your enthusiasm toward Alpha antenna, Alexloop, Chameleon Antenna, and G4TPH is heartfelt, and only meant to Enlighten the rest of the amateur radio Community to the awful marketing practices of these businesses? I am not sure that is true!
Before I continue, I am no stakeholder in Chameleon or any other business. Although it is said I get paid for reviews, I don't! I am just a guy who enjoys sharing the world of amateur radio, the outdoors, and the survival mindset.

Ok Dale, I can't debate about a manufacturers level of engineering skills. I just find it incredible that you are willing to ignore a fine product because you beleive someone without an advanced degree in engineering, would not possibly be able to build something superior to your own product. A product with your callsign on it, which you hold a patent application for, which is licensed(?) to LNR for production and sales.

Let us do a bit of fact checking
- You say on your PAR website "The primary design goal was to offer a loop, at lower cost, than what is available but with better performance, high quality construction and features not found on the currently available loops. To that end, this design has almost 100 parts, many of which require considerable machining to achieve excellent fit."
- - Cost LNR lists the W4OP loop at 329.99USB. If you add the tripod adapter, and the case the price increases. If you add te 6m kit, the price increases again. If you add shipping the price increases again. the Alexloop and Chameleon F loops include carrying case in the price (not hidden) the Chameleon has the tripod adapter integrated into the product at no extra charge. The Chameleon also has free worldwide shipping, and includes coax cable. Hell the P-LOOP even has the tripod adapter integrated into its base, and comes with the tripod. It also has the larger main and coupling loop kits. So yours/LNR sites are telling parts of the truth, but not the entire truth.

- Efficiency. Your comparisons (also copied word for word on LNR site) are based on your "calculations" but as far as I can tell, you have never actually had any of these competing loops in your hands, or given them to an individual lab for independent testing. Just so we understand. You have a patent pending on a loop with your callsign, sold by a company PAR (your company) made a deal with, which allows them to manufacture the W4OP loop, yet you are not a stakeholder? Ok, if we are to take this as truth, why are you basing your comparisons on the products as they existed 3 years ago? Alpha and Chameleon have larger standard loops as well as even larger main loop kits, and Chameleon has main and coupling loop kits which are larger and more efficient than your own (sorry I meant LNRs) W4OP Loop? Why have you not yet added the larger main and coupling loops and run your efficiency calculation again, publishing those results on yours and LNR websites? You said "The W4OP loop has no need to a booster kit",Ok fair enough. This tells me you and LNR don't understand how or the conditions man portable operators work in. An operator reviewing the W4OP loop on eham even said "The W4OP main loop is too big". The reason the Alpha, Chameleon, and Alexloops are smaller is not because they don't understand physics. It is because they understand they field operator! You can't manage that large loop in the conditions I normally operate in. So a smaller, lighter (even when its less efficient) loop, is more practical, than your larger, more efficient system. So I am agreeing with you on efficiency, but explaining what is obvious to a man portable operator.

Look Dale, I have an entire list of things which rips apart your marketing. I just don't see any need to go through it here. The main point is like the others, you present your truth which LNR copies word for word and pastes on their website. The difference is tey are not attacking you or LNR on every forum post you make. The problem with the tesxt found on yours and LNR websites, is it is limiting the truth to only those parts which work out best for the LNR W4OP loop (which has your callsign and you have a patent application for, but are not a stakeholder). The thing is, your math skills are excellent, you know others might not compete there with you, so you focus your marketing attacks of these small amateur radio antenna builders, in the only place you can, that is in the physics! Not my style, but you'll have to expect, people are going to call you and LNR out on it.

I am going to try to get one of the W4OP loops here to do an apples versus apples comparison. We are not going to just look at the math and models. We are going to take them to the field and test them in a way which is acceptable to the majority of hams interested in this thread.
we will look at
- ease of deployment
- time to setup
- weight
- break-down size
- and most important performance on all bands.

After the video shoot, I can give the W4OP away to some lucky operator who could only dream about it. The only winners will be operators who hate marketing, forum bullies, or simply want a truthful comparison about these products. By the way, you still have the W4OP loop on PAR pages, a company you are the president of.

Finally, It is very difficult to make a difference between You Dale, and LNR. I see LNR copies your out of date comparison material word for word so at the very least, you're trying to push sales of the loop with your callsign on it. I get that, but I don't think you should pretend you are not a stakeholder.
I'll get in touch with LNR. I'll get the loop here and validate your hostility toward other ham manufacturers. If it's awesome, we will know it. If it's better than the others, we will know that. If it is not so practical in the field, we will also get to know that.
From this point, i will stop hijacking Carls thread, and move this topic to my blog.
I promise you, it will be open and fair. I might even invite some of the other ham radio bloggers in EU to come up and validate the tests.

Kind regards
Julian

 

That's ok because I was done here anyway.....

- C

 

Good quality measurement is always needed to cement the point, but seems to not yet be available due to the tedium and detail required to do objective meaningful testing. I'm no expert on Loop Design, but I can say that I appreciate the math driven arguments. Sans good quality reproducible measured data, Math and Model are king - and I appreciate Dale's points, and references to Owen's always interesting and usually correct work.

 

This reminds me of the Ford Mustang versus the Fiat Spider back in 1978/79. The Mustang had greater horsepower, more torque, a higher top end, ... From an Americans perspective, it was a better "sports" car. It beat the Spiders specs in every way Ford tested. Fiat countered with a slalom test! The Mustang failed. It simply could not stay on a curved road. On paper it should have won.
have a good day operators.

 

Well, "model this." That's my opening gambit ... now onto the serious stuff!

"Modeling" (by OD) says the antenna used for the WSPR test run (six continuous hours) depicted in the image below was perhaps 'not worth the trouble' and nothing remarkable (not OD's exact words) as expressed in this online discussion (note: viewing on this website requires registration)

http://www.vklogger.com/forum/viewtopic.php?f=41&t=12406

... but note how *few* other US stations (about 5 plus me) are spotted by the Japan station JH1GYE in that six hours out of ALL the other US stations operating on the band!!!

The antenna that did this marvelous 'work' for me was a loop. Not a terribly small loop for 40 meters, but a tuned-loop nonetheless about 8 ft on a side (square) resonated with a capacitor and used on 40 meters not very high above ground:




Point being, LET'S get some field reports before falling back on only "modeling and math." When the modeling is incomplete, inaccurate or the modeling tools are misused and abused myth and speculation gets spread around as if it were truth and gospel.

BTW, I don't recall seeing the 'validation' testing of NEC4 with regard to 'grounds' and antenna performance. Maybe there has been some work in this area back when ...

Jim

PS I got similar results in the same time period with the same loop and a Russian spotting WSPR station as shown here: