Question on the Vector

[Shockwave]

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.

Perhaps you did but I don't recall anyone pointing out anything as stunning as a 1/2 wave shape in a 1/4 wave radiator before. To you it's just another anomaly in the model because you're not understanding there are a pair of currents on the cone forming this pattern. EZNEC only shows you one.

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.

Theory has a good deal of meaning behind what we see in CST and suggests you should be quicker to discredit the software that can't produce results that can be replicated in the field rather than the program that is teaching you things you haven't seen before.

We have to get over the "how is this possible" because were are years past this point now. You see it with the best software modeling tool available and I see it when only a 90 degree phase shift is required to bring another 1/2 wavelength into a constructive phase on the collinear test. In this case both the CST model and field tests agree there is 90 degree phase shift already taking place in the stock antennas radiated pattern.

The 1/2 wave pattern on a 1/4 wave radiator is only possible if certain conditions are met. First off, it is totally impossible to form if the cone only had one current present. It takes two RF currents on the radiator to make this pattern AND they must be separated in phase by 90 degrees so that their current nulls overlap at both ends and come to a minimum. It's actually very sensible once you understand what's happening.

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.

Opinions are acceptable when they don't contradict fact. It's not sensible to assume we can pick up 2dbd because of a few feet in height. The free space tests completely eliminates any chance of a height variable skewing the results. Unfortunately what you think in this matter is irrelevant since it doesn't line up with anything that works.

 

[Marconi]

Perhaps you did but I don't recall anyone pointing out anything as stunning as a 1/2 wave shape in a 1/4 wave radiator before. To you it's just another anomaly in the model because you're not understanding there are a pair of currents on the cone forming this pattern. EZNEC only shows you one.

Donald I agree, at first I did not see the 1/4 wave pattern for the cone looking like the pattern for a 1/2 wave radiator. The reason is, I did not think such was possible, but I did see that the pattern did not look like I expected for a 1/4 wave radiator.

I do see this pattern that CST produces as an anomaly that I don't understand. Even if you're right and there are CMC on the outside of the radials like you suggest, they would be radiating down from the top of the radials in a upside down 1/4 wave pattern and not in a 1/2 wave patter like we see in the CST image.

See EzBob images below:

This is a pattern from a S4 styled antenna with the currents turned on, and there are only two currents to be noted in the cone area. The fact that the antenna has two currents flowing on it does indicate it is collinear, but IMO that doesn't mean the antenna will manifest collinear gain.

We see the exactly same thing in a 5/8 wave antenna...a collinear antenna with no added gain over a 1/2 wave or 1/4 wave if the current maximums are at the same height. Thus the only difference we see is a height difference.

The EzBob image below is of a variety of wavelength patterns as noted. The open sleeve also shows only two currents flowing. They appear to have similar current magnitudes that are out or phase, thus there will be no RF flowing from the bottom of this open sleeve antenna. Only the top 1/2 wave has effective radiation into the far field.

This is a pattern below is from a S4 styled antenna with the current turned off, and we still only see two currents flowing in the cone area. CMC, only flows on coax with an imbalance at the load

Donald, I can only guess this new idea of a 1/4 wave showing a 1/2 wave pattern is new for Bob as well, because he does not indicate it in his image ideas at the top. I would like to know what Bob thinks about this idea.

 

[bob85]

i can see what donald means with the 1/2wave shape to the currents on the radials, never gave the shape much thought but i have talked about the two currents since i posted about the arrl open sleeve article where it talks about antenna mode and transmission-line mode.

 

[Marconi]

i can see what donald means with the 1/2wave shape to the currents on the radials, never gave the shape much thought but i have talked about the two currents since i posted about the arrl open sleeve article where it talks about antenna mode and transmission-line mode.

Bob, I've said the same, but the question is...does this 1/4 wave pattern look right based on what you know a 1/4 radiator pattern should look like?

 

[bob85]

the h-field and surface current distribution if thats what we are looking at in the animation does not look like the upper 1/4wave of monopole that has only one set of currents flowing as donald pointed out,

what would you expect to see if there were more than one set of currents flowing eddie ?

 

[Marconi]

the h-field and surface current distribution if thats what we are looking at in the animation does not look like the upper 1/4wave of monopole that has only one set of currents flowing as donald pointed out,

what would you expect to see if there were more than one set of currents flowing eddie?

I don't know what I would expect to see Bob, but if I was to guess, I would probably expect to see something like Donald describes. However, that would require some proof that I don't think we will ever see...even if we "think outside the box."

I doubt that CST can even show us the proof, and if it does it will not be noted in the image we see posted. For one thing the color scheme suggest that everything in red has 2.37 amps/meter. Because these colors are not discriminating enough to show us the nity-grity details in this far field pattern, it is suggested we see the current distribution of 2.37 A/m...from one end of the top 1/2 wave to the other. At best the value of 2.37 A/m is mostly in the center portion of the pattern, and its magnitude declines as we go out toward the ends to a really small value. Bob, IMO none of this jives with theory, but it is fun to look at.

The cone does not present a coaxial ratio that would perform like coax. As soon as the radials (shield) started to move away from the monopole (center conductor) the wires would start to radiate in an unpredictable fashion. This is why it is suggested to keep coaxial pig tail connections as short as possible...in order to help us minimizes as much undesirable RF as possible at the feed point.

Your EzBob image of the open sleeve antenna I posted above does not show 3 currents flowing in the area of the radials. My Eznec does not show 3 currents either, and I'm not sure what CST shows, but in my opinion it does not show 3 currents flowing there either.

Bob, what I see in the CST model is almost full cancellation inside the cone with a little difference in magnitudes between these two out of phase currents. If you compare the tops of both colors inside the cone I think you too will see this difference in magnitude. I see the blue color showing a bit more current than the red, and that is what my Eznec model shows. Check this point out and compare about 1" down from the top of the two radials where the color shade begins to fade in several little V shaped looking areas. The blue shows more current than the red and looks to me to be a bit thicker at the base as we might expect from a 1/4 wave element.

Note, the red shows to be the longer of the two which shows less current.

I also see this small difference radiating in to the far field and that difference can be constructive or destructive, but either way the RF is so small as to be meaningless. I also see these currents rising right up the outside of these radials, just like is does inside the cone. If we were seeing CMC flowing as you might suggest...we would see the current outside of the radials flowing down the radials. If you can find a slower motion of this image that the banned guy posted in another thread...you would see these currents are coming from the base of the cone, and going up to the top or out with horizontal radials...like all radials attached to a vertical monopole do whether slanted up, slanted down, or horizontal.

Tell me what you would expect if you somehow got 3 currents flowing in the cone area.

 

[bob85]

i don't know what to expect in the cst plot eddie, as i don't imagine just one set of currents and don't know how cst would display them,

which theory are you using eddie?,
it sounds like the theory that we only have one set of equal and opposite phase currents flowing in the lower 1/4wave,

it does not sound like you are using the theory in the arrl open sleeve article,

if you know what is going on eddie you must know what makes the vector different to the antenna described in the arrl and be able to demonstrate with models why the open sleeve radiates in phase and why the vector does not,
it may be obvious to those skillled in the art, please share,

have you modeled the open sleeve antenna as described in the arrl to see if your results match the claims eddie?,

the article gives several length permutations and describes what effects antenna mode impedance & current magnitude and what effects transmission-line mode impedance & current magnitude for comparison,

you could clear up what had cebik so confused about currents to the point that he told me the sleeve could radiate in phase with the upper 1/2wave and that there was more going on in the design than was aparent to most people,

nobody so far has said the article is wrong or tried to explain how the vector is different electrically,

we are stuck on the eznec merrygoround, or is it as cebik told me.

"pages of meanigless argument such misunderstood antennas can generate"

what is so misunderstood about a j-pole? he tells us all about j-poles and not one word of argument let alone the pages he spoke of, did he understand something you are missing eddie?

oh wait you don't believe Cebik said the things i claimed he told me,
radials can't act like a coaxial structure so he could never have had thoughts of anything that says the sleeve can radiate, which implys i made it up,

but what if he did say the things i claim ( which he did ) , is it possible that he understood something you are missing ?

or are of the opinion that even if bob was telling the truth the whole truth and nothing but the truth about what cebik told him, cebik was talking bullcrap anyway ?

 

[Shockwave]

Marconi, want to talk about an anomaly? How about you cannot build a working Vector with an extra 1/2 wave element on top using EZNEC NO MATTER WHAT YOU DO??? No offense but you talk about how I only have words to back my findings but the reality is I have 15 years of field testing to confirm how the Vector works while you've been posting an inaccurate opinion for nearly as long.

Endless hours have been spent explain to you that A PAIR OF CURRENTS ARE ON THE CONE. NOT ONE CURRENT. You go back to the model that can't demonstrate anything about how the antenna works in every case as if it defends your ideas. No kidding? Of course it agrees with your idea. The problems is both you and EZNEC have misidentified an important current that will prevent you from seeing the model results in field tests every time.

What part of your idea not working in any field test do you not understand? Does it not set alarm bells off in your head that a 180 degree phase delay cannot be used in a collinear model or is that just another anomaly too? Notice all of these hard to explain anomalies all relate to a difference in phase of 90 degrees? When you see a 1/2 wave current shape on a 1/4 wave element, don't assume you know more than CST and it must be wrong.

Ask yourself why until you realize it can only be possible when two currents are on the same element and separated by 90 degrees in phase. You have based all of your opinions of this design on a faulty model and one field test with a Targa and another antenna set up at the same time. I have formed a factual analysis of the radiation currents by experimenting with the phase shift required to stack another 1/2 wave constructively.

 

[Shockwave]

I don't know what I would expect to see Bob, but if I was to guess, I would probably expect to see something like Donald describes. However, that would require some proof that I don't think we will ever see...even if we "think outside the box."

"Seeing" the proof is entirely up to you since we have given you all the information required to prove it to yourself in the field. Yes, that does mean you'll have to abandon the faulty model to see what really works but you do have this option. It's not like you can't prove EZNEC is off by 90 degrees in phase calculations of this design, you just have to have the desire to go to the next step in field tests.

Tell me what you would expect if you somehow got 3 currents flowing in the cone area.

Exactly what CST shows. The 1/2 wave current shape on a 1/4 wavelength radiator.

 

[Marconi]

i don't know what to expect in the cst plot eddie, as i don't imagine just one set of currents and don't know how cst would display them,

which theory are you using eddie?,
it sounds like the theory that we only have one set of equal and opposite phase currents flowing in the lower 1/4wave,

Bob, I also said I did not know what I would expect. This is why I asked Donald a long time ago if he could post the currents per segment and phase information from the CST model...I thought he had.

You're right Bob, I think there are only 2 currents with opposite phase flowing in the cone area of the S4 design, and the magnitudes are almost identical...thus we see cancellation and little to no far field radiation from the cone.

it does not sound like you are using the theory in the arrl open sleeve article,

I'm simply using the coaxial theory:
Equal magnitude and opposite phase = cancellation, and thus we have no far field radiation.

Equal magnitude and same phase = far field radiation...like we see in a center fed dipole and a coaxial pig tail connections. Pig tail connections indicate what happens when we start to change the proper physical construction ratio for coax.

if you know what is going on eddie you must know what makes the vector different to the antenna described in the arrl and be able to demonstrate with models why the open sleeve radiates in phase and why the vector does not,
it may be obvious to those skillled in the art, please share,

Your EzBob model of the open sleeve antenna I posted above suggests the currents are turned on. This EzBob model does not suggest the sleeve radiates either...due to cancellation. Like the S4 design, this one also shows mostly cancellation within the sleeve area, and there is no CMC flowing from the top of the cone or on the radials. The only way I might consider a real sleeve antenna to radiate with CMC is with an end fed dipole using coax shield folded back over the coax as we see in the 2Tl2 (not sure of the name) and/or the Gain Master radiator using the shield, or the 1/2 wave antenna noted below in Bill Orr's book, "The Truth About CB Antennas."

have you modeled the open sleeve antenna as described in the arrl to see if your results match the claims eddie?,

the article gives several length permutations and describes what effects antenna mode impedance & current magnitude and what effects transmission-line mode impedance & current magnitude for comparison,

I did models as best I could on the monopole with 4 x 1/4 wave radials a 1/4 wave from the base of the monopole, but when I found my model named Open Sleeve dipole in the Eznec indes...it was a 1/2 wave center fed sleeved dipole, and not a vertical.

I have an Open Sleeve Antenna model like you mentioned, but I must have given it another name. I'll check and see if I can find it. I posted this model some time back, and made some comments regarding what I thought I saw using Eznec, but as I recall you shot me down. You said I did not understand the math. I didn't have a good argument due to a lack of understanding the article...so I dropped the whole idea. I may have deleted the models also, but I will look and if I find them I will repost.

you could clear up what had cebik so confused about currents to the point that he told me the sleeve could radiate in phase with the upper 1/2wave and that there was more going on in the design than was aparent to most people,

I don't think Cebik was confused about currents. I think maybe he was ill and did not want to get into discussing the topic...knowing it could be complicated and on-going...just like you suggested. I assume he died soon thereafter.

nobody so far has said the article is wrong or tried to explain how the vector is different electrically,

we are stuck on the eznec merrygoround, or is it as cebik told me.

"pages of meanigless argument such misunderstood antennas can generate"

Well Bob, I see where Donald has described several ideas for how he sees the Vector working, the latest of which claims, more or less, that the 1/4 wave cone radiates like a 1/2 wave radiator and he shows us that on the CST image he posted.

I don't know what Donald thinks about the OSA article, I don't fully understand what the article is all about either. Again, you made that clear when I posted the model of that Open Sleeve Antenna sometime back.

what is so misunderstood about a j-pole? he tells us all about j-poles and not one word of argument let alone the pages he spoke of, did he understand something you are missing eddie?

oh wait you don't believe Cebik said the things i claimed he told me,
radials can't act like a coaxial structure so he could never have had thoughts of anything that says the sleeve can radiate, which implys i made it up,

Bob, it was never about me not believing your words about talking to Cebik. You remember at first I believed what you were telling us, but now you forget latter when I got-off into modeling with Eznec...this is when I found no evidence of the gains you were suggesting, and started to disagree. We still don't know for sure what Cebik meant...and this is the issue. It has nothing to do with my believing you or not.

Before my learning to model, I did a month long test with my S4, consulting with you almost daily via emails. I learned some stuff about reactive antennas and feed point transformation during those discussions with you, but my testing proved nothing close to the gains...like you experienced.

If you what to know what pissed me off in regards to your words back then, long before Cebik and my modeling, I think you lead-me-on during the testing of my S4 noted above. Reason is, in the end you made the claim that the S4 was not able to produce the results you claimed with your Hybrid Vector. I wondered why you didn't just tell me that in the beginning. I never told you that my S4 did not work very well, quite the opposite, but you can't deny we were both frustrated and disappointed at my results in trying to help prove you right.

but what if he did say the things i claim ( which he did ) , is it possible that he understood something you are missing ?

or are of the opinion that even if bob was telling the truth the whole truth and nothing but the truth about what cebik told him, cebik was talking bullcrap anyway ?

No Bob, I believed you...I took up the challenge to try and learn modeling with the idea that one day I might be able to prove you right on the S4 design. I asked you to join me in that effort...but you said you were not interested.

 

[Marconi]

"Seeing" the proof is entirely up to you since we have given you all the information required to prove it to yourself in the field. Yes, that does mean you'll have to abandon the faulty model to see what really works but you do have this option. It's not like you can't prove EZNEC is off by 90 degrees in phase calculations of this design, you just have to have the desire to go to the next step in field tests.

Donald, I see the CST image just like you describe, but IMO that is not enough to prove the points you have made so far. I don't recall seeing any evidence of your field testing however.

BTW and just for the record guys, this CST image is Sorio's New Vector 4000, and not the Dominator that Donald makes...though they are similar by design.

And to refresh every one's memory...the overall length of the Sirio NV4K is a 3/4 wavelength or about 27' feet, and not like all the other lengths that have been suggested over the years as to the length that works best...from 29' - 31' feet.

Donald again, I see what you see in the CST image, but I disagree with you on what the image is showing us. It is a clever animation at best, but it is not really showing us much information as detailed antenna theory goes for currents on wires. Eznec does the same so they provide the Current Log so we can consider the details, segment by segment. That said however, very few that write about modeling discuss these currents.

Exactly what CST shows. The 1/2 wave current shape on a 1/4 wavelength radiator.

I don't deny this is what the CST model shows...I just disagree and say that is not possible with the cone as noted on the S4 design. IMO, the cone is not coaxial. I do wish there were some guru's that would talked about how modeling currents work. Maybe the subject is just too complicated.

Even if you are exactly right, and there are CMC's flowing on the cone...I don't see it possible for a 1/4 length wire to produce a 1/2 wave pattern. You are Bob show me how that might be...and I'll have something to consider.

My Eznec models that show CMC flowing on the mast show the first current pattern below the feed point making a pattern that is 1/4 wave down the mast as note below. So if we had CMC's on the S4 cone, they should produce a pattern that looks similar to the pattern below of a 5/8 wave ground plane model.

I exaggerated the currents a little for better clarity.

 

[Shockwave]

I'll sum this up real quick Marconi. WHY DO YOU INSIST ON RELYING ON A EZNEC MODEL THAT DOES NOT REPRESENT THE RADIATION CURRENTS PRESENT IN THE FIELD???????????????????? Your model will fail any phase test conducted in the field because EZNEC has never displayed an accurate model of the design yet. Not MHO either. The program is off by 90 degrees and for you to keep reverting back to it as thought it proves you right is insanity.

I ask that you hold all opinions of the antenna to yourself until you have taken the time to confirm them in the field as others have done. I use to believe EZNEC too until nothing it predict could be made to work in the field and one simple change in the phase delay made all exposed elements radiate constructively.

STOP asking us to consider a model that will not work in the field tests because they reveal EZNEC has miscalculated the phase by 90 degrees in the stock antenna. Therefore it misses the gain from the cone and cannot predict the phase shift required to stack another section. It is that simple. Do the work to confirm you idea or take the word of others that have proved your theory wrong.

If anything you said in that paragraph were correct, the 180 degree phase delay would work in a collinear field test. I beg of you to seek advice from anyone you consider unbiased that might make this test for you like Dale said he would and for you to stop beating a dead horse. To suggest the cone doesn't contribute noticeable to the gain of this antenna is ridiculous once you see it only works with a 90 degree phase delay.

 

[Marconi]

Donald this is pretty simple, my request is for you to prove what you claim...instead of just giving us words about you field tests and the idea about collinear stacking.

Check out the following link to a forum that discusses a collinear J-Pole project and tell me if the lower part of this idea is even close to what you did using a Vector antenna?

http://www.4x4ham.com/showthread.php?3019-Improved-2-Meter-Performance-with-a-Three-Element-Collinear-J-Pole

If so, then I will try your collinear stacked 1/2 wave on top of the S4 again.

 

[Shockwave]

Donald this is pretty simple, my request is for you to prove what you claim...instead of just giving us words about you field tests and the idea about collinear stacking.

Check out the following link to a forum that discusses a collinear J-Pole project and tell me if the lower part of this idea is even close to what you did using a Vector antenna?

http://www.4x4ham.com/showthread.php?3019-Improved-2-Meter-Performance-with-a-Three-Element-Collinear-J-Pole

If so, then I will try you collinear stacked 1/2 wave on top of the S4 again.

I looked at your article and it's nothing more than stacking 1/2 waves over an existing 1/2 wave radiator to form 3 sections. EZNEC will lie to you an report those very same collinear sections with their 180 degree phase delays will work on the Sigma too. Try that in the field and you will quickly see who is right.

You can add the collinear sections shown in that article to the Sigma but they will only work on the real antenna when you cut the phasing sections in half regardless of what the terribly flawed EZNEC models continuously report. Once again the reason is simple. The Sigma is not a 1/2 wave radiator like the J-pole in your example. The Sigma is the 3/4 wave radiator is has always claimed with a 90 degree phase correction taking place at the base.

PS: As much as you would prefer to claim my response is just words like your ideas, I must remind you that my words form a test that can be replicated in the field to prove the 90 degree phase discrepancy with EZNEC. Your words stop right there with nothing to back them or tests to confirm them because the idea is incorrect.

 

[Needle Bender]

Maybe I'm whack but I see it as a near-center fed fullwave with the bottom 1/4 wave inverted upward to invert & correct the phase & capture the other half of the bottom 1/2 wave.

Seems the cone section both captures and cancels the inner reverse-phase 1/4 wave current while it also compliments the upper in-phase 1/2 wave by radiating it's outward current as it's inward radiation cancels the outward radiation of the inner bottom 1/4 wave.

What happens when it's mounted on an insulator with a cmc choke in the coax wrapped just below the bottom of the cone?