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sigma4 article is online

People consider experts superior beings while forgetting that they are normal human beings who have the same mind that any human being has.

Whenever a person learns more about a subject, his mind becomes more rigid and less creative. Brain connections are developed when we use our minds more in creative ways but when we develop a single minded way of thinking sooner or later we will fail to see anything except what we have already learned. (Avanti was able to think outside the box with their invention of the sigma4)

An expert won't listen to you then evaluate your words but he will just compare whatever you say to his already existing database. If anything you said matched something he tried earlier then he will quickly predict the end results you will get.

However what most experts fail to notice is that past experience is never an indication of future results. Just watch how experts give recommendations about stocks and you will laugh. When they recommend a stock that keeps falling they shortly change their minds and recommend selling it and when it starts going up again they quickly recommend buying it.

Not all "experts" meet the your view of what an expert is. There are those that clearly do, and those that are no where close.

The most knowledgeable are those that aren't afraid to explore new ideas. This type of expert has a completely different approach, and if they tell you something isn't going to work, or you have something wrong (in the form of an absolute, not an opinion) they have several reasons for why that would be. They likely have access to reputable sources that go far beyond your knowledge on the matter as well. To them knowledge is only part of the story, what they really seek is understanding.

This type of expert isn't afraid to try things out. If you give them an idea they have yet to explore, they will explore it. That being said, their exploration of your idea can easily take them in a different direction, and a far different result.

A word of warning, be careful about absolute statements and implications such as your idea on experts. We humans like to fit things into nice little categories, however, very rarely do those categories fit all possibilities. There is far more than one or two kinds of "expert" in this world.


The DB
 
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Just to clarify, I'm sticking to this issue of CMC because the inaccurate claim has been made that Sigma "could" generate 2dbd "if" the mast length were ideal. That suggests all of the performance we have seen could be hiding in this one area. It makes this point key since it is the difference between everything and just being a unity gain 1/2 wave. I say that theory is disposable once you consider the advantages remain even with the coax and mast isolated.
 
Eddie,
No im not saying you should see more gain in free space,
Im saying the opposite is true.
 
Not all "experts" meet the your view of what an expert is. There are those that clearly do, and those that are no where close.

The most knowledgeable are those that aren't afraid to explore new ideas. This type of expert has a completely different approach, and if they tell you something isn't going to work, or you have something wrong (in the form of an absolute, not an opinion) they have several reasons for why that would be. They likely have access to reputable sources that go far beyond your knowledge on the matter as well. To them knowledge is only part of the story, what they really seek is understanding.

This type of expert isn't afraid to try things out. If you give them an idea they have yet to explore, they will explore it. That being said, their exploration of your idea can easily take them in a different direction, and a far different result.

A word of warning, be careful about absolute statements and implications such as your idea on experts. We humans like to fit things into nice little categories, however, very rarely do those categories fit all possibilities. There is far more than one or two kinds of "expert" in this world.


The DB


No offense meant, of course there's all kinds of people in this world. I am not that narrow minded. My post was directly in response to the Shockwave's post regarding an expert. It read like he was trying to close the door on the discussion and I feel there is more to come from anyone who wishes to comment.
 
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No offense meant, of course there's all kinds of people in this world. I am not that narrow minded. My post was directly in response to the Shockwave's post regarding an expert. It read like he was trying to close the door on the discussion and I feel there is more to come from anyone who wishes to comment.

L.B. Cebik was not a self proclaimed expert in the field of antennas. He earned that title and the respect of many. I was hopeful the door would be open to discussion however many of the theories being presented here simply don't make sense much less fit the antenna. If someone's theory suggests the 2dbd is coming from mast CMC and we know there is a choke and insulator present, I absolutely have to call BS. Then when they ignore the work of DB who made a model that could show CMC on the cone and that gain can be focused on the horizon, I have to call the lack of response to it denial.
 
The last question wasnt correctly answered by anyone..

New one:
When do we have a situation where we have a current moving though a conductor
which creates a magnetic H field....but NO radiation.

I must have missed that previous question... I'll have to go back and see if I can find it...

The first thing I think of when it comes to currents with no radiation is a feedline. It could be because the feedline was shielded like coax, or it could be because the feedline was constructed with a parallel conductor with current that is 180 degrees out of phase like ladder line. I know DC current was mentioned for this and that is a correct answer, however, I don't think that answer fits the context of this thread.

(edit : ps...bonus points for those who can name a situation where a current is traveling through a conductor but we do not have a magnetic H field .....you will receive 1 like and a thumbs up !)

I wonder if this was the previous question.

If you have current, by definition you have a magnetic H field. It is possible to contain the field, or cancel it out with an H field that is out of phase as I described above, but as I said, if you have electric current of any kind you have an H field.

The DB
 
Hello All

Just short ...as truly time is limited....its 0630 now...and still need coffee hihi....possible some time this evening. (constructing a house)

Yes, the correct answer to the first one would have been never....
gammegatter already knew that...
There always is an H field if you have current moving though a conductor.

And yes, it can be confined, as in the case of `coax`.

In case of no radiation.....transmission line,
Not really in the context of this thread...others...

I asked cause...well it was either that or to ask ....

For the... what is it ...10th time...
Donald....please answer my questions...etc...
Is there any proof that we can `see`...

Thank you...
Kind regards,

H>
 
For the... what is it ...10th time...
Donald....please answer my questions...etc...
Is there any proof that we can `see`...

Thank you...
Kind regards,

H>

Sure there is proof Henry and it's not in the paper work either for the 10th time. You have 3 people right in the forum that have seen with their own eyes the antenna has noticeable gain over other verticals. You've managed to convince some that it was 2dbd due to mast radiation even though chokes and insulators were used. Kind of defies any logic but that's where this report went. You've really done nothing but add to the controversy because you haven't provided a theory for this antenna.

Since you've inaccurately claimed to answer all questions, why not try an address the results that you can't squeeze into your theory? Don't answer the questions you wish you were asked. Answer how is it Bob, Homer, and myself see gain over a dipole EVEN WHEN THE MAST AND COAX ARE ISOLATED? Work with the material that cannot fit your theory for a change rather than to "explain it away". Suggesting that everyone's testing against inferior antennas or is not competent enough to measure the difference is really getting old.

I've stopped answering many of your questions because it's become obvious your ignoring the results and doing anything you can to "defend" 40 pages of J-Pole work. I've suggested you put the carriage in front of the horse because you've formed a theory that attempts to unprove existing results rather than one that could explain the results.

It's almost like you forgot this antenna has been around since 1979 and already has a well established performance record going back 36 years. We didn't need you to tell us if it works good or not. We were hopeful that you were going to explain why it works the way it does and were expecting the report to somewhat resemble what we see from the results. Not to rewrite what we see but to explain what we see.

The following eham link shows 10 more unbiased reviews from Hams using the antenna on 10 meters. http://www.eham.net/reviews/detail/4276 Can you find one review on that site that sounds anything like the theory you're presenting? Nothing you've written lines up with any of their first hand experiences. Why is that Henry?
 
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Donald,

Again you have not interpertated my findings correct.
I am not saying the antenna can not have an advantage of 2 dB.
You also fail to have noticed ....that the mast for example on the 1/2 wave end fed radiation plot in the article IS WITH a mast ISOLATED etc.

Donald, What I Do not agree with is:

1- Collinear theory
2- 5,15 dBI
3..etc....(cant remember them all m8)

So, these three people ....that is your proof ....i guess....
Any other proof is welcomed...you are the manufacturer...not me.


Kind regards

Henry

edit...sorry forgot the proof on your website made by the professional broadcast engineers...
 
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Donald
quote "my sig shows a vector 4000 on a fiberglass pole with a choke, feed-line need taping to the mast,
i did not have mine isolated like that, i tried isolation but no choke and a choke but no isolation years ago,
if id had the sense to do both i may have seen some improvement":(

Nowhere in this thread has anybody but you talked about cmc on the mast increasing gain by 2db or any db,
please go back and read the thread and read Henry's article so we can get on the same page.
 
Henry,

1) Collinear theory only requires more than one center of radiation along the same axis. Marconi and yourself seem to think I'm stretching it to inaccurately include an out of phase field from the base as we see in a end fed 5/8 wave. One that would produce the erroneously upward TOA you suggest with your J-Pole theory.

2) Not including the ground gain that 5.15dbi is the same gain the pairs of dipoles I've replaced and matched are. Two CP bays come in at about the same 2.15 dbi you claim this design produces and you have no clue how noticeable the improvement in coverage is over them once you hit the fringe zone. That's because you fail to see the possibility of manipulating the phase angles between two radiators in order to focus more energy on the horizon. You think it's one 1/2 wave element that can only have a loss in gain when using this effect.


Bob, I'm not sure if Henry made the CMC 2dbd statement in the 4 way conversation but I know Henry said something very similar. Specifically that it was possible for me to see the 2dbd in my tests but it wasn't due to collinear action but to CMC on the mast. Henry, do you deny making a statement to this effect? I really don't want to sort through all the pages in those conversations but if you're calling me out on this, I'll look and quote.

An alternative view point may be to just stop bickering about all the details and ask yourself why when you read Henry's article and then all the reviews on eHam here: http://www.eham.net/reviews/detail/4276 , that you can't tell they are even describing the same antenna other than physical attributes?
 
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Answer this simple question Donald,

What happens to signal strength received out towards the Horizon when you adjust your antenna away from its optimal settings ?
 
Bob, you know I know the answer to that and what you're next response is going to be. You also know if Henry's theory were correct that you could not exceed the gain of a 1/2 wave dipole on the horizon by manipulating these adjustments which is exactly what we see time after time.

I've been hearing how others are answering all the questions and I've answered none. Think we can get to any of the last few I've raised? Anything from the reviews not matching the article to Homers totally isolated version still showing the same typical results with no CMC on the mast or coax?
 
Donald,
The best situation is when the antenna is 3/4wave electrical and the cone is 1/4wave electrical, that gives the best balance and least cone radiation, Imho that's what we did,

moving away from there causes the cone to radiate more and phase to shift in the cone area which causes low angle radiation to drop and high angle radiation to increase,

So if you start with a stock vector or avanti you can cause more signal on the horizon through adjustment of relative cone and monopole lengths like i said from day 1,

Henry told us as much in the conversation but in reverse,
starting from optimal you can only cause low angle signal to drop,

The same applies to a j-pole as seen in the link i posted,
The j-poles i built and tested years ago were obviously not as good as Henry's j-poles, and now i see where i likely went wrong as do the majority of people that build them and install them,

Henry did mentioned the cmc on the mast with different length masts while keeping the antenna at the same height can effect the signal, go read it again, He's not saying what you think he is,

If you tuned yours on a 1 wavelength mast you can see 2db over a dipole as Henry's graph shows, no requirement for any collinear gain,

If its top mounted or as high as possible as you advise it could have better coverage than other antennas
But the design won't make the various gain figures you have claimed 2dbd 3dbd 5.15dbi 6db.

eham, well one guy says the vector has slight edge on the 827,
and another says it equaled his moonraker 4 to locals, go figure,

I can't speak for homers tests but what Henry tells us agrees with what you claimed before you got the cst animation,

quote Shockwave "Using a simple field strength meter will confirm almost nothing is being radiated in the area of the cone" "The more important question should be how does the cone section improve performance"

I think Henry has answered your question.
 

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