New thread to debate V-4000

[nosepc]

Just remember, you're getting what you paid for building this antenna in that software. About 10% of the total picture and understanding of the design. Using that you make a feeble attempt to unteach the other 90% of how it works in the field as tested by people even more skeptical than yourself.

Tell your BS to Clear Channel or CBC Canada. I'm sure they will be interested to know their engineers were completely incompetent (according to you) when measuring the field strength of their licensed broadcast stations.

As you have only used words. Never ever mathematical proof, not even a model other than that already refute CST animation. You do not have anything more?
You will think I am an amateur?? At 16 years old I operated a broadcasting, it was my uncle. At 18, studied electronics, years later took out my first amateur radio license. Work years in radio, tv, technical service HT, fabricate my own antennas, 32-element collinear array vhf and many more things that are irrelevant. You can count me as an antenna works.?

Agree that if the cone radiates self sides canceled by having inverted phases and opposite, so the irradiation of the cone is useless, it only works as an impedance matching element for feeding the radiating half-wave as any J-POLE

If you own a model that refute my statements, would be good to publish it, especially the cone in question "that works collinear".

"no see"

 

[Mudfoot]

 

[Shockwave]

As you have only used words. Never ever mathematical proof, not even a model other than that already refute CST animation. You do not have anything more?
You will think I am an amateur?? At 16 years old I operated a broadcasting, it was my uncle. At 18, studied electronics, years later took out my first amateur radio license. Work years in radio, tv, technical service HT, fabricate my own antennas, 32-element collinear array vhf and many more things that are irrelevant. You can count me as an antenna works.?

Agree that if the cone radiates self sides canceled by having inverted phases and opposite, so the irradiation of the cone is useless, it only works as an impedance matching element for feeding the radiating half-wave as any J-POLE

If you own a model that refute my statements, would be good to publish it, especially the cone in question "that works collinear".

"no see"

Really NoSee? Did we have to go to comparing experience because you won't acknowledge anyone's field tests of the CST model even when they are conducted by independent engineers at commercial radio stations like KOLG I directed you to?

By the time I was 20, I'd already spent the equivalent of over $40,000 obtaining an education from the highest rated electronics school in the North East. Graduating top in my class the school recommended me to one of their best employers through their job placement program that filled government contracts.

For 2 years I was responsible for aligning the RF detectors used in one of the most sophisticated, unmanned flying objects built at the time before leaving to start my own business in the commercial broadcast field. I didn't find being locked in a clean room all day aligning tiny gold coils under a stereo microscope and network analyzer very rewarding.

Also held an advanced class license for nearly 20 years and worked for Motorola Two-Way division while in school for 4 years. Radio may be your hobby in which you are very opinionated but it's my profession. Working with other professionals in the field and hearing their feedback on this design daily, places me in a position to call you full of sh*t.

 

[Robb]

 

[Shockwave]

LOL Robb. I can't believe anyone would accuse me of tooting my own horn there

Now I see M42's horn post and think I was confused as to who's horn was referring to what. In any event we were both horn tooting and on goes the Sigma Saga.

 

[HomerBB]

Since changing the spacing at the bottom of the cone changes impedance, it will depend on the range your gamma match has to determine if finding a match will be easier or not as a result. I actually had to modify the gamma match slightly when the hub was introduced to perfect the new match.

I had to work on the gamma, too.
That may have been the most trying piece of the antenna to get right. I made several iterations of the gamma before I had one that would control the match properly.

 

[nosepc]

Us agree that we then radiates radio frequency cone??. OK!!
But how do we do it in the direction we want??
We put a compass in hand and say: "look, I want to radiate as I will; not like you do"??

The model shows that the cone is in antiphase with the rest of the radiant, so it does not radiate in phase, and the rest of the radiation is canceled itself.

The last image is a polar or azimuth of the antenna, where radiation are cone in every way and contrary phases.

 

[Shockwave]

Us agree that we then radiates radio frequency cone??. OK!!
But how do we do it in the direction we want??
We put a compass in hand and say: "look, I want to radiate as I will; not like you do"??

The model shows that the cone is in antiphase with the rest of the radiant, so it does not radiate in phase, and the rest of the radiation is canceled itself.

The last image is a polar or azimuth of the antenna, where radiation are cone in every way and contrary phases.

Just words based on worthless software you paid nothing for and got nothing from in this case. Add four wires and test the software yourself.

 

[Robb]

LOL Robb. I can't believe anyone would accuse me of tooting my own horn there

Now I see M42's horn post and think I was confused as to who's horn was referring to what. In any event we were both horn tooting and on goes the Sigma Saga.

Yeah, it was meant for nosepc, you just posted quicker than I did is all.

 

[The DB]

The last image is a polar or azimuth of the antenna, where radiation are cone in every way and contrary phases.

A major problem with your argument here is it is only true if the radials are on the same plane, (or are perfectly horizontal) and spaced evenly apart. Once any of this changes your tug of war analogy is no longer accurate.

I, personally, don't like that method of showing phases. It is highly misleading to those who don't know what they are looking at. Phase is *NOT* a line that is coming off of the antenna in a certain direction. The direction of the line is simply an indicator of the motion of the field that exists around the specific point of the antenna. If you have two radials that go in opposite directions that are fed by the same source, say one (but not both) of the wires that feed the antenna, the rotation, and thus phase, of the fields generated by said radials would be exactly opposite each other. This condition can *ONLY* exist as long as the radials are pointed in exact opposite directions.

Once you begin to angle the radials, and it doesn't matter if you angle them up or down, so long as they are no longer perfectly horizontal, the fields they generate are no longer exactly out of phase with each other. As a matter of fact, as the angle between the radials decreases the fields they generate begin to add up and act more and more like a single field. Actually, this is technically incorrect, their fields combine to create two separate fields. One of those fields exists only on the outside of the angled radials and is thus transmitted outwards, much like the set of radials were a single element. The other field exists on the inside of the radials and is trapped by the radials themselves and not allowed to radiate. These two fields are exactly out of phase with each other.

This same principle is why a quarter wavelength vertical antenna with radials that are angled down at a 45 degree angle acts like something in between a quarter wavelength vertical with horizontal radials and a half wavelength vertical dipole.

I have yet to see any NEC2 based models that can accurately show any of this. Not being familiar with the math behind the Method of Moments algorithms that make the software work (at least not yet...) I am not sure if it is possible. Remember, the Method of Moments that is used was originally designed to be used on machines with punch cards and limited processing capability. Even today most NEC based software uses text files that simply simulate this punch card data for both an input and output, then interpret said virtual punch cards to generate the pretty graphs and plots we see posted. Essentially NEC based software is still using decades old technology with decades old limitations. Even NEC4, which you have to pay for ($300 currently), has the same underlying technology. Honestly, over 20 years ago I used to directly manipulate data files that were generations beyond this technology.

I'm not saying the technology isn't useful, but in todays world why do we limit ourselves to such an old technology, aside from the fact that CST costs so much...

And for the record, you clearly have not debunked the CST data shown, and a good part of the reason you haven't is actually explained above in this post. You still haven't met the challenge I made back in that discussion... I'm still waiting...

One more thing, how many reasons have you listed to explain why the radials cannot effectively radiate anything into the far field? Many of these reasons are contradictory, which means they cannot all be right at the same time. So which explanation is it?

Actually, the correct answer to that question is non of them. I only asked to point it out. So who is just words?


The DB

 

[Robb]

Once you begin to angle the radials, and it doesn't matter if you angle them up or down, so long as they are no longer perfectly horizontal, the fields they generate are no longer exactly out of phase with each other. As a matter of fact, as the angle between the radials decreases the fields they generate begin to add up and act more and more like a single field. Actually, this is technically incorrect, their fields combine to create two separate fields.

Think I see what you are saying, DB. Since the cone is inverting the current, the 4nec2 software can't model it and therefore render it correctly. While the CST software did catch it. OK. The mystery of the Sphinx is solved.

 

[nosepc]

A major problem with your argument here is it is only true if the radials are on the same plane, (or are perfectly horizontal) and spaced evenly apart. Once any of this changes your tug of war analogy is no longer accurate.

I, personally, don't like that method of showing phases. It is highly misleading to those who don't know what they are looking at. Phase is *NOT* a line that is coming off of the antenna in a certain direction. The direction of the line is simply an indicator of the motion of the field that exists around the specific point of the antenna. If you have two radials that go in opposite directions that are fed by the same source, say one (but not both) of the wires that feed the antenna, the rotation, and thus phase, of the fields generated by said radials would be exactly opposite each other. This condition can *ONLY* exist as long as the radials are pointed in exact opposite directions.

Once you begin to angle the radials, and it doesn't matter if you angle them up or down, so long as they are no longer perfectly horizontal, the fields they generate are no longer exactly out of phase with each other. As a matter of fact, as the angle between the radials decreases the fields they generate begin to add up and act more and more like a single field. Actually, this is technically incorrect, their fields combine to create two separate fields. One of those fields exists only on the outside of the angled radials and is thus transmitted outwards, much like the set of radials were a single element. The other field exists on the inside of the radials and is trapped by the radials themselves and not allowed to radiate. These two fields are exactly out of phase with each other.

This same principle is why a quarter wavelength vertical antenna with radials that are angled down at a 45 degree angle acts like something in between a quarter wavelength vertical with horizontal radials and a half wavelength vertical dipole.

I have yet to see any NEC2 based models that can accurately show any of this. Not being familiar with the math behind the Method of Moments algorithms that make the software work (at least not yet...) I am not sure if it is possible. Remember, the Method of Moments that is used was originally designed to be used on machines with punch cards and limited processing capability. Even today most NEC based software uses text files that simply simulate this punch card data for both an input and output, then interpret said virtual punch cards to generate the pretty graphs and plots we see posted. Essentially NEC based software is still using decades old technology with decades old limitations. Even NEC4, which you have to pay for ($300 currently), has the same underlying technology. Honestly, over 20 years ago I used to directly manipulate data files that were generations beyond this technology.

I'm not saying the technology isn't useful, but in todays world why do we limit ourselves to such an old technology, aside from the fact that CST costs so much...

And for the record, you clearly have not debunked the CST data shown, and a good part of the reason you haven't is actually explained above in this post. You still haven't met the challenge I made back in that discussion... I'm still waiting...

One more thing, how many reasons have you listed to explain why the radials cannot effectively radiate anything into the far field? Many of these reasons are contradictory, which means they cannot all be right at the same time. So which explanation is it?

Actually, the correct answer to that question is non of them. I only asked to point it out. So who is just words?


The DB

We agree that You are right in words, then I can explain what is the correct side of the antenna?
Whose side currents are in phase with the radiating cone.

I would like to see that in CST, or if possible, better proprietary software from NASA.





NO SEE.

 

[Henry HPSD]

Hello Guys,

By far a accurate model....in aspect to "real" measurements.
And i havnt 'tweaked" it in any way.
The model was just to see ....what would happen.

Was thinking in the line of...what if the cone was made so dense it became the "cage of faraday".
(leaving the top open though)

if anyone is interested...the model is can be received send me a pm.
The model is has about 2000 wires so cant put it on the forum.
(roughly its 9 meters long....2.7meters for the cone and 60cm diameter.)

Now, the thing that "strikes" me...
The antenna is resonant lower in freq (roughly 1..2 Mhz)
the impedance is around 30 J0.
But at the higher frequency (29,5 in this case). The antenna provides gain with a good AGT.

That allone gives me hope we migth find the solution

Anyway...just thougth drop it on the forum for those who are interested.

 

[The DB]

We agree that You are right in words, then I can explain what is the correct side of the antenna?
Whose side currents are in phase with the radiating cone.

I would like to see that in CST, or if possible, better proprietary software from NASA.

NO SEE.

Your talking about the cst data again? The one where you mistakenly used a tug of war between the left and right side of the main antenna element to try and show nothing would radiate?

What appears to you as the two different fields in those pictures, including the animations, are actually the same field in a 3d space. If you could actually see the field you would see that it is spinning around the antenna. The phase simply determines which way it is spinning at a given time, and the magnitude determines the size of the given field.

Think of it like a wheel on an axis, and the axis is the antenna. On one side of the axis, say the right side, the wheel is moving towards you and the other side, say the left side, the wheels spin is moving away. This will be true no matter which way you are looking at said field (or wheel), even someone on the opposite side of the antenna will see to their right side the wheel moving towards them and to their left side the wheel moving away. Unfortunately, those CST plots are limited to a two dimensional output, so to some it looks like there are opposite fields on both sides of the antenna.

Going beyond this to explain what is happening with the radials on this antenna gets even more complicated as the fields generated do not simply add or subtract, they fully interact with each other to create effectively two additional combined fields, one contained completely inside the radials, and the other outside of the radials that act as a single in phase field that radiates.

I have yet to see (admittedly in my small modeling experience) an NEC based software actually account for these fields interacting with each other.

NEC based programs (at least 4nec2, eznec, and an-soft100) seem to take the data for the field being generated by the various segments, and instead of calculating their effects in a 3d environment simply add them together to give an output. And this is fine, right up until you have an antenna design such as the Vector, or any antenna with angled radials that form a cone shape, or travel largely in the same direction (up or down more than 45 degrees).

Looking at the .out files used by the NEC2 core, all of the data needed to calculate the vector data for these fields in space is there. Only from that point can you calculate the vector data of these fields interacting with each other. No one has, as of yet, written a program that can do that, short of CST. Until the authors of an NEC based program goes these extra steps with RF field vector calculations, NEC based software will never be able to effectively model this antenna. Simply adding the effects of the different elements is not enough.

There, I'm on the record as saying it. It isn't an unequivocal statement by any means, but there it is.

Now comes the challenge to everyone, show me a NEC based program that actually calculates not only the field vectors, but the vectors generated by the fields interacting with each other in and around the antenna.


The DB

 

[Henry HPSD]

Could you make it a bit more clear for me ?
As i am trying to understand your question at this point.
ill try to re-read again later as im probarbly just overseeing things....so much to do hihi.

As from this point i think...
No more than 45 degrees ?.....well how about 90 degrees ? a yagi ?...a Moxon ? etc.

fields interacting ?
Again...how about that same directional antenna ?

Kind regards,

Henry