sigma4 article is online

[bob85]

Donald,

I have not changed my mind about the vectors performance over other antennas, or that we can observe signals peaking out in the distance and make them perform better than either avanti or sirio as you and i have been saying for years,

I have my own mind, nobody convinces me of anything unless it makes sense to me,
I learned the right and left hand rules in school physics, its not something Henry made up,
Henry just turned on the light switch,

Im always willing to learn if you can provide evidence that the cst plot is not showing the near magnetic H-field in A/m as Henry claims,


I Don't know if Henry will shoot my theory down or not, If im wrong it won't be the first time and won't be the last,

I have a different view of what is likely going on when we tune our antennas for best signals,

To have radiation from the cone beyond that produced by the lack of cancellation caused by the radials not been parallel would require common mode due to imbalance at the top of the cone as seen in the j-pole,

You said the signal peaks when the hoop is close to the zero crossing point using 1/4wave radials,

That means you have an electrical 1/2wave above the cone with highest possible impedance, least possible imbalance of impedance between the high end impedance of an electrical 1/2wave and the very high impedance of air at the top of the radials = least magnitude of cmc on the cone,

Adjusting the monopole in ether direction makes the distant signal drop,

Ergo,
When you cause the top of the lower 1/4wave to see a lower impedance by adjusting monopole length to something other than an electrical 1/2wave above the cone & create more imbalance and more cone radiation the signal drops,

That's what happens in a j-pole when you extend the monopole towards 5/8wave,
downside is more signal goes into higher elevations at the expense of low angle radiation,

http://www.hamradio.me/antennas/58-wave-j-pole-vs-12-wave-j-pole-eznec-shootout.html

So we are in fact manipulating takeoff angle or the field strength at low angles, but not in the way i first imagined,
Rather than gaining something we are reducing what others throw away,

That's how it looks to me unless somebody can prove otherwise, LINKS PLEASE,

Technically you don't have to have a capacitor as seen in the cx series from sirio,
you could adjust the antenna for resonance and play with the diameter of the gamma rod or monopole to get a good match without a capacitor,
But that would not allow us to do what we do adjusting our antennas.

 

[Henry HPSD]

Donald:

Oke, take a look at how i see things:

1) My first question is did you read where I specifically mentioned at the time I shared the photo that is was only for our private use and not to be published anywhere? That would be on page 12 of the private conversation involving the four of us.

Yes I remember you asked not to use your photo.
So i didnt, I used mine.

2) If you read that, do you somehow feel my concerns about this topic should be different since you haven't used my actual photo but one of the similar antenna you made afterwards for the same test?

No im afraid i dont feel those concerns, perhaps it is me mistinterpertating though.
After our findings I am looking at it as doing you a favour by not mentioning them in my article. nI think that was more then kind of me, obvious you do not have to agree, but it is how i see it.
I recall that as my promisse to you, wasnt it ?
If my promisse was anything other, i will remove it at onces and I will do anything to make up to you, as "faith" for me is important.
Im trying to be as honest as i can, Im always trying to be as open minded as i can
And im always willing to admit if i was wrong.

But what do you expect, what are you expecting for future reference ?
You have asked so many times to different people to construct the 4 wires test.
I did.....Again I said i wont use it in my article. Thats it....
The antenna is relative simple to construct.
It has nothing to do with "showing off"
And there are all ready pictures online of such not made by me.

Kind regards,

Henry

 

[Henry HPSD]

(click to enlarge)
@ DB,

Does the above sound (looks) logical ?
The far field pattern you are optimising now is made up due to the antenna and the ground around the antenna upto say about 10..20 wavelengths...
After that it goes "up" in the sky..

Look at it as "rugby"...
Your the last guy standing between the incomming ball near the two poles.
The "enemy" has two options:
At far distance from the "goal" ? there is a guy who kicks against that ball as hard as he can under an elevated angle...hoping it reaches target....goes over it...outside the arena and lands who knows where...

You are now looking at someone who does "skip communication"
But you were that last defensive person...you are watching from close range at that goal...at ground level...you want "close" communication.
Its not funny standing there each time to see that ball go over...

What you want is someone running with that ball towards you so you can tackle him and save the day.

So dont optimize for max gain up high...
You want maximum strenght at ground level.

dont think those superbowl guys were thinking of this when they scream to "get down"

edit:
That is why those diagrams in my article are so important.
I have done calculations that way and i dont think anyone else has ever done that for CB use.
I have included all the differrent waves possible and provided details of what would happen at 30 Km away at a receiving location :
http://cb-antennas.com/?page_id=965 first pdf page 33 and 34.

The value of that information is hugh, and is not seen anywhere else.


kind regards, H>

 

[Shockwave]

Donald:

Oke, take a look at how i see things:

1) My first question is did you read where I specifically mentioned at the time I shared the photo that is was only for our private use and not to be published anywhere? That would be on page 12 of the private conversation involving the four of us.

Yes I remember you asked not to use your photo.
So i didnt, I used mine.

2) If you read that, do you somehow feel my concerns about this topic should be different since you haven't used my actual photo but one of the similar antenna you made afterwards for the same test?

No im afraid i dont feel those concerns, perhaps it is me mistinterpertating though.
After our findings I am looking at it as doing you a favour by not mentioning them in my article. nI think that was more then kind of me, obvious you do not have to agree, but it is how i see it.
I recall that as my promisse to you, wasnt it ?
If my promisse was anything other, i will remove it at onces and I will do anything to make up to you, as "faith" for me is important.
Im trying to be as honest as i can, Im always trying to be as open minded as i can
And im always willing to admit if i was wrong.

But what do you expect, what are you expecting for future reference ?
You have asked so many times to different people to construct the 4 wires test.
I did.....Again I said i wont use it in my article. Thats it....
The antenna is relative simple to construct.
It has nothing to do with "showing off"
And there are all ready pictures online of such not made by me.

Kind regards,

Henry

Well that doesn't really seem logical to me since the concern was what the picture showed and not who owned the picture. Redoing it to use your own photo doesn't really change that. If you think hiding I was wrong about interpreting the meaning of the 4 wire test is doing me a favor, you missed the fact I've already announced that error in the public forum. I have no concerns about that and am only concerned with accuracy and respect for confidentiality when requested.

I was wrong about the reason for the 90 degree phase delay working in the 4 wire test but not the fact a 90 degree phase delay works in this application. The interesting part is Bob pointed out facts that prove the 4 wire test is not capable of proving what I thought it did. It neither proves or disproves the collinear idea since it works because the radiators were 5/8 wave. Doing me a favor would have been to recognize showing the photo now serves no benefit to the discussion and who took the picture makes no difference.

 

[Shockwave]

The far field pattern you are optimising now is made up due to the antenna and the ground around the antenna upto say about 10..20 wavelengths...
After that it goes "up" in the sky..

The flaw in that theory is we have never tried to peak gain in skip or with skywave and all the gains that have been seen are achieved through distant line of sight propagation.

 

[Henry HPSD]

Hello Shockwave,

Well, if you allready have said it your 4 wire approach was wrong.
What would it all be so "hot" for you to mention ?
What difference does it make ? And indeed i was under the impression it was about your picture not mine, if i missed the context i am sorry.
But then there is no harm done for you as you allready mentioned it.
Hoping you also realise i did say i wont use it in my article.
My hopes are you can have some "lack" for my honesty....as i have nothing to gain from not beeing.

In aspect to your second remark, for more important then a picture.
I disagree Donald.
You say "we" never peaked for gain at skip angle...
But what do you think DB is doing now with his model ?
my posting was intended for DB not for you, thas why the @dB remark is there.
DB is the one modelling the antenna with the elevated angle.

That you have done some field tests with the use of "direct wave" is clear to me.
And nothing to do with the subject.


Kind regards,

Henry.

 

[The DB]

@ DB,

Does the above sound (looks) logical ?

At first glance, yes, but it only stays that way if I choose to ignore both my knowledge of theory and the experiences I have had communicating with antennas...

When you are over a non-perfect ground, as is present in all parts of the real world, the gain at the angle of the horizon (o degrees) is so small for any and all antennas that it is effectively 0. The GHZ24 model you provided, for example, has a gain of -198 dBi at horizontal if it is mounted at one wavelength over the 4NEc2 Average Ground. To try and put that in perspective, a gain of -63 dBi is 0.0001% of 1 dBi, and that number is rounded up. That is the smallest amount of gain the calculator I use can handle before just saying 0%. In either case, using only the horizontal angle of radiation you are referring to you aren't transmitting enough power to talk to the guy across the street, much less miles away.

If what you are saying is true, I would not be able to talk to someone on the other side of a hill that completely blocks direct wave signals, yet in the real world I can and do on a consistent basis. I'm sure you know why. The same reasoning is why a mobile antenna can talk to another mobile station 20, and sometimes even 30 miles away, in both cases if the earth doesn't block the direct wave, the stations would be at an angle from each other that if your diagram posted above were strictly true communications would be impossible. In fact, communications that your diagram above show should be impossible happen every day.


The DB

 

[Shockwave]

If we don't start addressing some of the obvious differences seen in the Sigma it will be very easy to stretch this debate out another 5 or 10 years.

1) Many are arguing there is no significant radiation present outside the cone but they also want to overlook the fact they have never seen a 1/4 wavelength radiator produce a field in the shape of a 1/2 wave "arc". That also makes it easy for them to overlook that one current is not present on the outside of the cone but there actually has to be two to make the field shaped that way.

2) The theory Henry is trying to promote requires the cone be made from radials and he suggests there are individual fields rotating around each of the 4 radials with a strong interaction between the radials and monopole that cause near complete cancellation in the far field. He's sure it works like a single leg J-Pole but simply has more symmetry. Install wire mesh over your cone so we can move on to plausible theories please.

 

[Henry HPSD]

Db,

of course what i say is true

I did not say you can not talk with someone behind something....
Thats why i put in that blue not straigth line....there are things as "groundwave / surface wave / refelcted wave etc.

Now, what you are doing is looking at the skywave.
You are looking at a elevation plot and set the cursor at 0 degrees.
That is not correct....

There are other options.

The traditional Eznec has NO option to do otherwise.
You can either calculated the near field or the far field.
That far field will show the elevation or azimuth pattern.
(skywave) it does NOT include the groundwave.

The PRO version of Eznec CAN include all the diferent waves (except the reflected one obvious)....hence the diagrams i have provided which are so valuable.

If you look in 4NEC2 you will find the OPTION SURFACE WAVE
Now, i still dont know if that option includes everything (i havent asked yet sorry)

But it will give a indication of what I am saying.
Please do some inverstigation before you depend on the calculations.
Its important to realise what that option can calculate.
Possible the original NEC manual would give some insight.
As horizontal and vertical antennas have different ground losses etc.
So..be carefull pse...as im not aware of how 4nec2 handles those.

Realising you do not have the "pro" version, i searched on the intenet to find some more info.
I came across a nice freeware ! for fun !
http://www.cplus.org/rmw/english1.html

With such you can provide plot of your "station coverage"
I did so with two yagi's
1 with no degrees down tilt
and 1 with 15 degrees down tilt

 

[Henry HPSD]

If we don't start addressing some of the obvious differences seen in the Sigma it will be very easy to stretch this debate out another 5 or 10 years.

1) Many are arguing there is no significant radiation present outside the cone but they also want to overlook the fact they have never seen a 1/4 wavelength radiator produce a field in the shape of a 1/2 wave "arc". That also makes it easy for them to overlook that one current is not present on the outside of the cone but there actually has to be two to make the field shaped that way.

2) The theory Henry is trying to promote requires the cone be made from radials and he suggests there are individual fields rotating around each of the 4 radials with a strong interaction between the radials and monopole that cause near complete cancellation in the far field. He's sure it works like a single leg J-Pole but simply has more symmetry. Install wire mesh over your cone so we can move on to plausible theories please.

1- I do not understand what you indicate with "1/4 wave radiator produce a field in the shape of a 1/2 wave arc...
Could you explain ? (ps picture or so will help)
2-There is ALWAYS a magnetic H field around a conductor with a travelling current.
(o well...not always of course ...but in case of a "radiator/radials" ...yes...)

What would that wire mesh do Donald ?...what is that you are expecting ?

And indeed i would like to move on...like i have asked several times:
Please provide some proof...of your 5,15 dBI collinear theory.
anything will do. (besides your explination of the CST plot)
Now, if you want to move on to more "plausible" theories...
Why dont you proof mine wrong, im happy with that too.

Kind regards,

Henry

(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 !)

 

[Marconi]

You guys are really getting good now...I don't understand any of the points being made and that reassures me that the truth may be very near to being revealed .

 

[Shockwave]

1- I do not understand what you indicate with "1/4 wave radiator produce a field in the shape of a 1/2 wave arc...
Could you explain ? (ps picture or so will help)
2-There is ALWAYS a magnetic H field around a conductor with a travelling current.
(o well...not always of course ...but in case of a "radiator/radials" ...yes...)

What would that wire mesh do Donald ?...what is that you are expecting ?

And indeed i would like to move on...like i have asked several times:
Please provide some proof...of your 5,15 dBI collinear theory.
anything will do. (besides your explination of the CST plot)
Now, if you want to move on to more "plausible" theories...
Why dont you proof mine wrong, im happy with that too.

Kind regards,

Henry

(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 !)

1) Just look at the field around the cone in CST. The currents generating this field are have more magnitude towards the center than either the top or bottom portions of the field. Exactly the same shape as the 1/2 wave field on the monopole above but only half as long. I thank DB for being one of the only people to give this some serious thought and not just ignore it as an anomalies. Modeling shows that can only be accomplished when more than one current is present on the cone.

2) Indeed there is the field around the conductor but you see the cone as individual elements rather than a complete single structure. This allows your theory to work as opposed to the "confinement" theory offered by the engineer who built the CST model. If your theory were right, the individual radial fields would be greatly effected by the monopoles field spinning in the opposite direction inside the cone.

The mesh around the cone inhibits any possibility of your theory being applied to the antenna since it forces you to see the field around the cone is one and RF simply sees the cone as a single wide band radiator with a flared end. This also supports the engineers explanation that the action taking place within the cone is more related to confinement than cancellation. It also supports years of excellent field results where your theorized 0.1dbd spec could not.

 

[The DB]

Ahh, now that is potentially useful information...

Your right, I don't have the "Pro" version of EZNEC, and actually, I don't have any version of EZNEC installed on my computer right now.

Strange, there is really not anyone posting how to use/read the Surface Wave option in 4NEC2, the manual didn't really help either, but I think I have the gist of it. Why didn't you direct me to this a few posts ago? It would have made things much easier...

When looking at the vertical chart it produces, this always seems to be at a kilometer out, I wonder if I can change that somehow... I still need to learn how to read this data properly... Experiment time, well, it will be once I get more time to play with modeling...

And Henry, when something like this happens, ask if I know about, or have used features like the surface wave option in 4NEC2 you just mentioned. I'm self taught, and I learn by doing. I also don't tend to stray into other screens like this without reason. Sometimes I just don't know I have reason to go somewhere...


The DB

 

[Henry HPSD]

Ahh, now that is potentially useful information...

Your right, I don't have the "Pro" version of EZNEC, and actually, I don't have any version of EZNEC installed on my computer right now.

Strange, there is really not anyone posting how to use/read the Surface Wave option in 4NEC2, the manual didn't really help either, but I think I have the gist of it. Why didn't you direct me to this a few posts ago? It would have made things much easier...

When looking at the vertical chart it produces, this always seems to be at a kilometer out, I wonder if I can change that somehow... I still need to learn how to read this data properly... Experiment time, well, it will be once I get more time to play with modeling...

And Henry, when something like this happens, ask if I know about, or have used features like the surface wave option in 4NEC2 you just mentioned. I'm self taught, and I learn by doing. I also don't tend to stray into other screens like this without reason. Sometimes I just don't know I have reason to go somewhere...


The DB

Yes you can change distance and "readings" and altitude etc.
But I also have seen some results that worried me, that's why I didn't provided it in first place but asked to hold on till I had confirmation.

The issue is not you Db, and if you do have something ...just ask...
I know you learn fast and do so for most by your self.
However there are many who read along...and will publish results as they think they are "true". I already don't respond to all that is not accurate.

Search on google for the original NEC manuals
Im confident I have seen a chapter on it somewhere...that's what I have done in the past....I printed all those manuals and started reading....rather difficult job for adhd high hihi.
Anyway, I "know" Arie a bit (not drinking coffe with him or so) and I know he is not into "4nec2" at the moment, occupied with other things.

Glad it is of use !

Have fun

H>

 

[Marconi]

Donald below is a Antenna View of the current in the cone area for my Eznec Sigma 4 model.

Do you see such a current formation on the red line near the radial that represents current that looks like the pattern for a 1/2 wave radiator in this Eznec model? NO!

In the case of the pattern you posted it may be nothing more than a perspective at a bad angle for the still shot we are looking at. I've taken pictures of my antennas down the street a bit, so I could get the perspective for their height relationships, and the image turned out showing the antennas looking bowed or bent over and not vertical. We have to consider the optics that may be a play here.

It is not possible for a 1/4 wavelength element to produce a 1/2 wave current pattern and you should know that, and it does not take all these high tech words to describe.