Question on the Vector

[Shockwave]

Ok, Donald so your idea is the only one that counts. If your idea about this antenna design were true, like you claim, it would be the hottest antenna on the market, but hardly anybody ever talks about their NV4K, and the idea would seem to scale nicely into other bands as well...and I have never heard of this design outside of 10-11 meters and your FM product of course.

You suggest that even Cebik would have considered this antenna to be a far superior design...but I find nothing in his body of work on the subject.

W8JI, has recently updated his article on "End-fed Vertical and J-Pole," and he demonstrates ideas using slanted up, slanted down, and horizontal radials on a J-Pole. He doesn't say much, but he did not make any claims to increased gain except where so noted and it wasn't much gain anyway. He also may have added this idea of slanted up radials to the J-Pole as a result of the eHam thread that Booty Monster posted and you mentioned above. If you recall he did comment in that thread at one point.

He did comment that this idea could be make coaxial by using a pipe in a similar configuration, but did not show an example and gave no further details.

He also says nothing about this radial idea creating a collinear effect that increases gain on the J-Pole.

Here is the link: http://www.w8ji.com/end-fed_vertical.htm

You are right about one thing using these Antenna Software design programs...if you don't get the antenna design right as to the physical design we know works, and consider the product limitations...no model will likely give good results. I noted about this in my remarks above...so you will possibly know why Eznec did not work for you in your efforts to model your S4 idea. I'll bet you did not consider any of those design ideas back then when you made Eznec models.

Ideas either become fact or fantasy once the time is taken to conduct tests that prove them to be reality or myth. It's not my idea that EZNEC has screwed up by one 1/4 wavelength of radiation phase in every model it spits out. Until the program can correctly display the radiation phase of the cone with respect to the vertical above it, It's not possible consider any results produced in EZNEC or opinions based on those results.

You'll never find anyplace where I suggested Cebik said anything more than the antenna functioned as a "non apparent collinear" because that's the only important comment he offered. Having 2dbd is hardly the "hottest antenna" either. It is however enough to make a nice improvement in the FM mode where the difference in signal required to quiet the receiver can be very small. I do my best not to exaggerate and ask you do the same when attempting to quote me.

Pretending that EZNEC just doesn't work for me or has something to do with my models is ridiculous. Can you add the 4 wire test to any of your models and make a collinear work at a 90 degree phase delay that represents the field tests? All I'm asking is that the damn model get close before you rely on it so much. Not within 10% or 20% either but being off 100% too long throws the "baby and the bathwater" for modeling this antenna with EZNEC right out the window.

 

[Marconi]

Ideas either become fact or fantasy once the time is taken to conduct tests that prove them to be reality or myth. It's not my idea that EZNEC has screwed up by one 1/4 wavelength of radiation phase in every model it spits out. Until the program can correctly display the radiation phase of the cone with respect to the vertical above it, It's not possible consider any results produced in EZNEC or opinions based on those results.

Eznec does show the correct phase for the cone and the top 1/2 wave radiator above, if you follow the rules and consider the limitations published in the Manual. If you were sitting beside me Donald, I could show you how the currents in the base of the radiator inside of the cone track right along, amp for amp per segment, with the sum of the amperage in each radial...although they are of the opposite phase. This is how cancellation occurs in the cone, and there are only two out of phase currents in the S4 cone area...not three as you suggest. The cone is not coaxial, and does NOT work like a sleeve...which can act coaxial provided we have correct sleeve dimensions for the design frequency.

You'll never find anyplace where I suggested Cebik said anything more than the antenna functioned as a "non apparent collinear" because that's the only important comment he offered. Having 2dbd is hardly the "hottest antenna" either. It is however enough to make a nice improvement in the FM mode where the difference in signal required to quiet the receiver can be very small. I do my best not to exaggerate and ask you do the same when attempting to quote me.

That comment was made because you talk about this "non-apparent collinear" idea on your Dominator Website. IMO, you did that because you consider such words as a benefit, and the assocaiation with the name Cebik does not hurt your promotion efforts either.

I have never said there is NO "non-apparent collinear" effect in the cone of the S4 design. I just claim the benefit is very small due to cancellation, which you totally ignore, while claiming instead that there is CMC in a third current path on the outside of the radials flowing out from the top of the cone.

Pretending that EZNEC just doesn't work for me or has something to do with my models is ridiculous. Can you add the 4 wire test to any of your models and make a collinear work at a 90 degree phase delay that represents the field tests? All I'm asking is that the damn model get close before you rely on it so much. Not within 10% or 20% either but being off 100% too long throws

If you believe what you claim here Donald...prove it. Show us something.

I use to believe what I think you and Bob are saying, but I can no longer accept your words simply based on the notion...I consider you two as Good Guys.

 

[Shockwave]

Eznec does show the correct phase for the cone and the top 1/2 wave radiator above, if you follow the rules and consider the limitations published in the Manual. If you were sitting beside me Donald, I could show you how the currents in the base of the radiator inside of the cone track right along, amp for amp per segment, with the sum of the amperage in each radial...although they are of the opposite phase. This is how cancellation occurs in the cone, and there are only two out of phase currents in the S4 cone area...not three as you suggest. The cone is not coaxial, and does NOT work like a sleeve...which can act coaxial provided we have correct sleeve dimensions for the design frequency.

So you can add the 4 wires forming a 90 degree phase delay and EZNEC now reports it resembles what can be repeated in the field tests? If not that entire statement and your idea is still false. You've ignored everything the field tests represent regarding the phase almost as well as EZNEC. Just to be clear, it's not possible to say EZNEC displays the correct phase when the delay it wants to see in a collinear is 100% too long.

That comment was made because you talk about this "non-apparent collinear" idea on your Dominator Website. IMO, you did that because you consider such words as a benefit, and the assocaiation with the name Cebik does not hurt your promotion efforts either.

The comment was therefore inappropriate. There is a huge difference between what I said in my direct quote of "non apparent collinear" and your fabrication of "Cebik would have considered this antenna to be far superior" You actually did what you're complaining about in taking the man's quote out of context. You're claim of "very small gain" is relative. Let others decide is they consider 2dbd to be small gain because if your idea of "small" is different, you're misleading the members in the forum based on models proven to be flawed.

I have never said there is NO "non-apparent collinear" effect in the cone of the S4 design. I just claim the benefit is very small due to cancellation, which you totally ignore, while claiming instead that there is CMC in a third current path on the outside of the radials flowing out from the top of the cone.

Stop ignoring the fact I have absolutely proved the cone radiates in phase with significant magnitude to cause a 2dbd gain increase. Recognize that the 180 degree phase delay proves this since when it's used, no gain can be seen due to cancellation of this desired current you think is so small.

If you believe what you claim here Donald...prove it. Show us something.

I use to believe what I think you and Bob are saying, but I can no longer accept your words simply based on the notion...I consider you two as Good Guys.

I believe my eyes. What you believe is not even remotely possible and if you were able to take your ideas to the field you'd dismiss them as quickly as I have. If you can longer accept my words, understand that those words are based on sound evidence that can be easily repeated in the field. Understand none of your ideas can be taken seriously because they already have been proven incorrect.

 

[Shockwave]

Here are a few more things to consider. W8JI mentioned that this antenna would benefit from a set of 1/4 wave horizontal radials because it should have high levels of CMC on the mast and coax. Hoping he was right I tested this simple idea even though I noted no CMC issues on the antenna when tuned properly.

Adding horizontal radials caused a small drop in signal. Not what anyone including myself expected. I expected there would be no change. The fact there is a reduction in gain strongly suggests the added horizontal radials are taking constructively phased current away from the tapered cone in the vertical plane. The gain only returns to normal when the added horizontal radials are swept upwards like the originals.

Another thing no one else has noticed in the CST model is the shape of the 1/4 wave current on the outside of the cone. Any 1/4 wave radiator I've ever seen before had the source of the current shown at full current and the far end at minimum. When was the last time you ever saw a 1/4 wave radiation current with minimum current on both ends and the maximum current in the middle???

The base of the 3/4 wave vertical also has a much different shape than normal in the CST model. At peak current from the source, there is minimum current at the base of the vertical??? Shouldn't it be maximum there like EZNEC shows it? There can only be one reason for this that that would be the 90 degree offset in phase I've been telling you for years that EZNEC fails on.

I'm still not sure how this is happening but I know it's related to the 90 degree phase delay inside the cone acting as transmission line for the 1/2 wave above it. This appears to cause two currents to flow (one is CMC) on the outside of the cone that are separated by 90 degrees in phase, but still in a constructive phase with each other. This is why the typical 180 degree phase shift used in collinears reveals results that have not been seen before when applied here.

 

[The DB]

When you say the bottom of the vertical are you talking about the inside of the cone above the radials, or the outside of the cone below the radials?


The DB

 

[Marconi]

When you say the bottom of the vertical are you talking about the inside of the cone above the radials, or the outside of the cone below the radials?

The DB

If you are talking to me? When I'm referring to this particular point...I try to remember to always describe the bottom of the monopole...and that means the bottom where the radials and the radial hub is attached.

Can you be more specific where this phrase was used?

 

[The DB]

I was talking to Donald.


The DB

 

[Shockwave]

Neither the current inside the cone on the vertical or the current on the outside of the cone represent the typical 1/4 current with a peak at the source. Both the inside current on the vertical and the outside 1/4 wave current begin and end with minimum current. The current peak is in the middle of both 1/4 wave elements. An indication of two 1/4 wave currents with an offset in phase by 90 degrees.

 

[Marconi]

So you can add the 4 wires forming a 90 degree phase delay and EZNEC now reports it resembles what can be repeated in the field tests? If not that entire statement and your idea is still false. You've ignored everything the field tests represent regarding the phase almost as well as EZNEC. Just to be clear, it's not possible to say EZNEC displays the correct phase when the delay it wants to see in a collinear is 100% too long.

Donald I may be the only guy around that understands what you mean when you say,

So you can add the 4 wires forming a 90 degree phase delay and EZNEC now reports it resembles what can be repeated in the field tests?

You make this claim about being able to stack a S4 with a 1/2 wave wire above it using 90* degree phasing and making it work.

I'm not here to prove your work. This is why I asked you to show us something.

The comment was therefore inappropriate. There is a huge difference between what I said in my direct quote of "non apparent collinear" and your fabrication of "Cebik would have considered this antenna to be far superior" You actually did what you're complaining about in taking the man's quote out of context. You're claim of "very small gain" is relative. Let others decide is they consider 2dbd to be small gain because if your idea of "small" is different, you're misleading the members in the forum based on models proven to be flawed.

Donald, I stand by my comment.

We have no idea what context Cebik really meant in Bob's conversation with the man. I asked Bob what all that meant back in the days right after he communicated with Cebik, and as best I recall Bob suggested the idea supported some notion that the whole antenna radiated, and Bob has further stated many times that the Avanti S4 box was printed with some words saying the "Whole Antenna Radiates."

There is more to how all of this unfolded in the past, here on WWDX archives, before you ever signed on to this forum. Believe it or not I remember the first day when you signed on. Does that sound like someone I did not listen too?

Stop ignoring the fact I have absolutely proved the cone radiates in phase with significant magnitude to cause a 2dbd gain increase. Recognize that the 180 degree phase delay proves this since when it's used, no gain can be seen due to cancellation of this desired current you think is so small.

If you have absolutely proved the cone radiates significantly producing a 2db gain increase, I was not convinced.

I believe my eyes. What you believe is not even remotely possible and if you were able to take your ideas to the field you'd dismiss them as quickly as I have. If you can longer accept my words, understand that those words are based on sound evidence that can be easily repeated in the field. Understand none of your ideas can be taken seriously because they already have been proven incorrect.

I would like to accept your words, but I see this subject differently and I have seen nothing to indicate that I'm wrong. This is why I asked you to produce something for us to look at that might really be convincing.

This is also why I spoke to DB recently regarding currents.

 

[Marconi]

Neither the current inside the cone on the vertical or the current on the outside of the cone represent the typical 1/4 current with a peak at the source. Both the inside current on the vertical and the outside 1/4 wave current begin and end with minimum current. The current peak is in the middle of both 1/4 wave elements. An indication of two 1/4 wave currents with an offset in phase by 90 degrees.

Donald, I see the same thing. The CST image does not present a typical 1/4 wave pattern around the cone area...it looks more like a 1/2 wave pattern.

 

[Shockwave]

Donald I may be the only guy around that understands what you mean

Not at all. It's just that those that understand have yet to follow through with any field testing to confirm for themselves. Easier to just say no than to follow through with testing.

You make this claim about being able to stack a S4 with a 1/2 wave wire above it using 90* degree phasing and making it work.

I'm not making any claim based on my humble opinion. I've simply taken the time think up a test that could confirm or deny ideas about the phase and magnitude of the cones radiation and reported what the field tests revealed.

I'm not here to prove your work. This is why I asked you to show us something.

You're a bit funny the way you ask for proof but when I tell you how to replicate the test so you can see it with your own eyes, you imply "you're not here to prove my work". What is the purpose of the time spent on this topic if you're not here to find the truth? Redundantly sharing opinions based on flawed models will continue to receive the same response here. You wouldn't be happy until I drove to Texas and did the work for you displaying the 90 degree error.

Donald, I stand by my comment.

You stand behind your comment because you need it to imply more that my quote of "non apparent collinear". Without that it's nothing more than a truthful quote from a well educated man that supports CST and field tests.

We have no idea what context Cebik really meant in Bob's conversation with the man. I asked Bob what all that meant back in the days right after he communicated with Cebik, and as best I recall Bob suggested the idea supported some notion that the whole antenna radiated, and Bob has further stated many times that the Avanti S4 box was printed with some words saying the "Whole Antenna Radiates."

There is more to how all of this unfolded in the past, here on WWDX archives, before you ever signed on to this forum. Believe it or not I remember the first day when you signed on. Does that sound like someone I did not listen too?

You may have no idea what Cebik really meant because you're not familiar with field testing of the phase or what the CST model displays. Quoting the shipping box as stating the entire antenna as radiating is also correct. I remember unpacking mine in 1986 and CST proved it a few years ago.

If you have absolutely proved the cone radiates significantly producing a 2db gain increase, I was not convinced.

You won't be convinced unless you build and field test a collinear version. Even then you may struggle to understand why only a 90 degree phase delay works. That this proves the cone radiates virtually as effective as any standard 1/4 wave element because the 180 degree delay shows no gain at best.

I would like to accept your words, but I see this subject differently and I have seen nothing to indicate that I'm wrong. This is why I asked you to produce something for us to look at that might really be convincing.

This is also why I spoke to DB recently regarding currents.

I have little faith that you would like to accept my words based on the effort you've put towards placing yourself in denial over any important issues regarding the topic. Nearly every post I've made is packed with info that would lead anyone to the same conclusion that was willing to invest the time to test it. Sadly you rely on EZNEC over CST, Cebik, or field tests.

As of now the ONLY thing I'm interested in discussing is how it's possible for the Vector to form 1/4 wave currents inside and outside the cone that have peaks in the center and not at a an end. Look at the EZNEC model and both the cone and radial currents are maximum at the base. Not at all what we see in CST. CST shows what looks like a 1/2 wave current on a 1/4 wave element.

You've never seen a 1/4 wave current shaped like this and I suggest there is only one way to form that pattern. It requires two 1/4 wave currents to be present on the element that are separated in phase by a 90 degree shift. That is the maximum phase shift you could have between a pair of 1/4 wave currents while still keeping the entire length in a constructive phase.

It is extremely likely the second current is the CMC folding back over the outside of the cone since we need the two currents with their 90 degree phase offset to have their individual sources at opposite ends of the 1/4 wave radiator to form this shape pattern. The fact that the pattern current peaks in the center suggests these two currents are close in magnitude otherwise the peak would be somewhat off centered.

I see where everything being debated all hinges on this odd shaped 1/4 wave radiation current in the base. That includes all failed EZNEC models, the collinear field tests, Cebik's description of the antenna and the 2dbd free space gain. Knowing all this, I can't take 10 steps backwards to consider any model that misses the radiation phase by 90 degrees. Still sound like just words?

 

[Marconi]

Here are a few more things to consider. W8JI mentioned that this antenna would benefit from a set of 1/4 wave horizontal radials because it should have high levels of CMC on the mast and coax. Hoping he was right I tested this simple idea even though I noted no CMC issues on the antenna when tuned properly.

Donald are you saying that the J-Pole does not have a reputation for having CMC problems? W8JI was suggesting CMC problems with the J-Pole/Vector in Booty Monster's thread on eHam too.

It is an endf

ed half wave- so same gain as a dipole IF you can keep radiation currents off the mast and the outside of the coax- this is the downfall of all of the groundplanes, J poles etc.
W4OP

I see a smart antenna person on verticals and groundplanes who knows how they work and what the problems are has arrived on scene.

Try reading what Cebik writes at the bottom of page 3, in one of Bob's regular references, "Some J-Poles That I Have Known." This page is posted below, but I doubt you will bother to read it, because it shows you have your head in the sand.

The only problem with the J-Pole IMO is a result of its being out of balance at the feed point a bit, no matter what you do. I use to believe much of this crap about our vertical CB antennas being out of balance, and thus CMC's being a hugh problem that basically rendered our antennas usless...but I now say horse hockey in most cases. CMC's may be a much bigger problem with ham multiband antennas, but not the commercial CB antennas we have available...including most of the EF Solarcon antennas.

I think CMC's currents can produce problems if their magnitude is worst case, but if these currents are minimal and within reason...this idea is mostly BS we hear about the operations of our CB radios. The only thing I see being a problem is interfering with other nearby electronics. If you eliminated all CMC's in your antenna I suspect you could see no operational differences in performance with our commercial line of CB antennas. This dose not mean there are not differences that can be measured using high tech devices...it means you are not likely to see differences using your radio because the differences are so subtle.

Adding horizontal radials caused a small drop in signal. Not what anyone including myself expected. I expected there would be no change. The fact there is a reduction in gain strongly suggests the added horizontal radials are taking constructively phased current away from the tapered cone in the vertical plane. The gain only returns to normal when the added horizontal radials are swept upwards like the originals.

I don't understand this at all.

Another thing no one else has noticed in the CST model is the shape of the 1/4 wave current on the outside of the cone. Any 1/4 wave radiator I've ever seen before had the source of the current shown at full current and the far end at minimum. When was the last time you ever saw a 1/4 wave radiation current with minimum current on both ends and the maximum current in the middle???

I've posted about this here on WWDX, but nobody responed or else, like you suggest, nobody noticed or understood what I was describing. I also posted this idea on eham, and one other member that I remember agreed with me.

The base of the 3/4 wave vertical also has a much different shape than normal in the CST model. At peak current from the source, there is minimum current at the base of the vertical??? Shouldn't it be maximum there like EZNEC shows it? There can only be one reason for this that that would be the 90 degree offset in phase I've been telling you for years that EZNEC fails on.

I agree with the first part of your observation, but I do not think it possible to phase shift a 1/4 wave element like I think you are trying to suggest. Maybe this is what DB was asking about in his short post above.

Donald IMO this is another anomoly that I think you see, and are trying by some words or silly idea to justify. The Sigma 4 antenna is a very good antenna for a lot of reasons, but there is nothing magic about it.

I'm still not sure how this is happening but I know it's related to the 90 degree phase delay inside the cone acting as transmission line for the 1/2 wave above it. This appears to cause two currents to flow (one is CMC) on the outside of the cone that are separated by 90 degrees in phase, but still in a constructive phase with each other. This is why the typical 180 degree phase shift used in collinears reveals results that have not been seen before when applied here.

You're just guessing here, but that is alright with me.

 

[Shockwave]

Donald are you saying that the J-Pole does not have a reputation for having CMC problems? W8JI was suggesting CMC problems with the J-Pole/Vector in Booty Monster's thread on eHam too.

Of course not. I built my first J-pole decades ago and found it was a decent coax radiator. I'm aware of CMC with the J-pole. The better question is do you think the end fed Sigma wouldn't have CMC had these currents not been radiated from the cone? When W4OP and W8JI can fit a 1/2 wave current shape over a 1/4 wave radiator into their explanations, we can begin to consider them and why the 90 degree collinear experiment works.

Try reading what Cebik writes at the bottom of page 3, in one of Bob's regular references, "Some J-Poles That I Have Known." This page is posted below, but I doubt you will bother to read it, because it shows you have your head in the sand.

Nothing shows one's head in the sand like their denial to accept what works in the real world in favor of a flawed model year after year after year. No reason to read about J-Poles. Nothing there can explain the 90 degree phase shift taking place in the "non apparent collinear " antenna.

The only problem with the J-Pole IMO is a result of its being out of balance at the feed point a bit, no matter what you do. I use to believe much of this crap about our vertical CB antennas being out of balance, and thus CMC's being a hugh problem that basically rendered our antennas usless...but I now say horse hockey in most cases. CMC's may be a much bigger problem with ham multiband antennas, but not the commercial CB antennas we have available...including most of the EF Solarcon antennas.

I think CMC's currents can produce problems if their magnitude is worst case, but if these currents are minimal and within reason...this idea is mostly BS we hear about the operations of our CB radios. The only thing I see being a problem is interfering with other nearby electronics. If you eliminated all CMC's in your antenna I suspect you could see no operational differences in performance with our commercial line of CB antennas. This dose not mean there are not differences that can be measured using high tech devices...it means you are not likely to see differences using your radio because the differences are so subtle.

I've also seen a few installations where an Antron 99 had little RFI problems and was able to work surprising skywave propagation. Just a few blocks away someone with the same antenna is never heard in DX and has a good deal of RFI problems. These same situations have been noted in many installations. The difference is mast and coax length used and the phase of the CMC that freely radiated without choke or resonant path to bleed the currents off.

Do not underestimate the damage CMC can do to an antennas pattern if the CMC is not effectively addressed at the antenna. When the CMC is allowed to radiate in a destructive phase, it causes high angle lobes to take power away from the horizon as well as causing RFI.

I don't understand this at all.

It's simple. W8JI expects there to be significant CMC still present on the coax. He also anticipates this CMC will be radiating in a deconstructive phase in order for the "pattern to fall apart once the coax and mast are added". I added them and the gain dropped a few tenths of a db with virtually no change in the perfect match. I bent them up and the missing gain returned.

Some of the productive CMC current on the cone is forced to divide between the cone and the horizontal radials. The diverted currents on the new radials is essentially wasted since it's in the horizontal plane. Leave the end fed CMC currents exactly where Herb placed them. On the resonant cone where they benefit gain while reducing RFI.

I've posted about this here on WWDX, but nobody responed or else, like you suggest, nobody noticed or understood what I was describing. I also posted this idea on eham, and one other member that I remember agreed with me.

One member agreed with you on what point? That the shape of the 1/4 wave pattern was odd? Was any other point made or conclusion drawn? Pointing something out falls short of explaining what we see in a manner that fits sound RF theory and the results which can be repeated in the field.

I agree with the first part of your observation, but I do not think it possible to phase shift a 1/4 wave element like I think you are trying to suggest. Maybe this is what DB was asking about in his short post above.

Donald IMO this is another anomoly that I think you see, and are trying by some words or silly idea to justify. The Sigma 4 antenna is a very good antenna for a lot of reasons, but there is nothing magic about it.

Why am I not surprised? How about this, I agree, you can't see the phase shift I'm talking about. Now can we please move onto why this is the case and stop accepting data from a model that will not produce a model that resembles the 90 degree phase offset we can clearly see in the field?

You don't see this offset in phase using EZNEC because it has only been able to accurately predict one of the two currents required to place a 1/2 wave shaped current on a 1/4 wavelength radiator. When you only see one current correctly, it is not possible to form a current like this. You only get the maximum current at the base like your EZNEC models continue to misrepresent.

Your humble opinion once again borders being insulting as I watch you use it as an excuse to stand behind your idea in favor of what works. I'd like to hear your "idea" about how that pattern is formed at the 1/4 wave base of the Sigma??? If you can make it fit what works in the field along with what we see in CST like I did, that would be the icing on the cake.

You're just guessing here, but that is alright with me.

Guessing is what one does when they do not have the ability or time to test their own ideas for themselves and has to endlessly wait for others they consider unbiased to test the idea for them. In the meantime, they are forced with no other option but to guess. Sound familiar?

This is vastly different from someone who suspected the typical models have misidentified a 1/4 wavelength of radiation current and then comes up with a way to prove the 90 degree phase discrepancy with the collinear field tests. Who is really guessing Marconi?

 

[Marconi]

Why am I not surprised? How about this, I agree, you can't see the phase shift I'm talking about. Now can we please move onto why this is the case and stop accepting data from a model that will not produce a model that resembles the 90 degree phase offset we can clearly see in the field?

You don't see this offset in phase using EZNEC because it has only been able to accurately predict one of the two currents required to place a 1/2 wave shaped current on a 1/4 wavelength radiator. When you only see one current correctly, it is not possible to form a current like this. You only get the maximum current at the base like your EZNEC models continue to misrepresent.

Your humble opinion once again borders being insulting as I watch you use it as an excuse to stand behind your idea in favor of what works. I'd like to hear your "idea" about how that pattern is formed at the 1/4 wave base of the Sigma??? If you can make it fit what works in the field along with what we see in CST like I did, that would be the icing on the cake.

Donald, the only thing I will admit concerning the CST image...is that I do see exactly what you claim to see. I just disagree with what it might mean.

I have questioned this issue about the 1/2 wave pattern on the cone before, and if I looked back it was probably before you even noticed what you're claiming now is going on in the cone area at the bottom of the NV4K.

If theory has any meaning at all, the fact we see this on the CST image makes no sense, and should at least cause one to question what you see that you have never seen before. How is it possible for a 1/4 wavelength radiating element, that is 50% of a 1/2 wave, to produce a pattern that looks like a 1/2 wave pattern? You should at least question this...just like I think most sensible folks would.

Back in the days HyGain use to refer to their CLR2 antenna as a collinear, and we all should know why...simply because the antenna produced two current maximums...to heck with the fact that the bottom section of a 5/8 wave was out of phase with the top 1/2 wave radiator, and made little to no contribution to the antenna performance at all.

In my opinion the only thing these longer element antennas provide over a standard 1/2 wave antenna is a possible small increase in gain due to an increase in the height of the current maximum. And, I think the same is true with the Sigma4.

 

[Lil'Yeshua]

May I interject something here. I have no proof or material to back my theory but I think that at the very least,the basket shapes the radiation pattern overall. It that's of any value then we could go off that premise or if anyone has a thought that sounds viable would be welcome.
It's time to leave the safe confines of present theory and beliefs and push out into the unknown.
Everyone has an unique gift given to them. It's up to those waiting in the wings that have an yet unproven theory to step up to the plate and contribute to this Incomplete equation.
Also,I think that a co linear antenna of similar proportions should be field tested and then the V4K.
It's just a thought but you know,though a difference of beliefs and opinions are a healthy recipe for stretching present theory and knowledge.
Both models may not fully explain the process by which the B4K operates but can be a stepping stone towards a better equation.
Think outside the box.