DB, when I posted my opinions (IMO) and concerns to Bob...I had not yet made any current models including a mast for this design or made any models in Free Space. As usual, I had only tried to duplicate your overlay results. I did it that way only as a starting point considering the topic. Those models were over Real Earth and did not include a mast.
I also did not add a hub to the models in my overlays...as you can see in my second PDF file (Horizontal model to start, etc.) posted above, the radials are connected directly to the radiator.
I also posted my considerations for doing Free Space models and tried to explain why, but again I had not made such models.
I was not considering CMC at that point, because those models had no mast or feed line to indicate the presence of such currents.
The only difference I could see is you models showed less gain as the radials were slanted down...and my models showed a slight increase in gain. I also saw a notable difference in the patterns...so I took the chance to try and figure out why without asking.
My model with 3 horizontal radials that I started with..produced similar matching results as you reported. So, I had the idea we might have close to similar models to start. If you did something different with your model...then it did not show a change in the match. I attributed the difference in patterns I was seeing to your using a Poor or Extremely Poor ground description in your model settings.
DB, I have done the same I'm sure, but I usually can find an old model that is close to the idea to be considered. I do this as a starting point and produce a new model without trying to remember stuff.
Here we see Wavrider talked about CMC and asked whether you modeled a feed line and mast. That comment got me curious enough to open my Eznec and check out if there was a discernible difference between a 1/4 wave ground plane with and without a mast or feed line. What struck me there was...how would anyone know if there were CMC on a model with no mast or feed line wires to indicate such currents?
No DB, I did not use a hub in the models posted above, but I did think it might be good idea if we included the mast for the Real Earth models.
I did not check my models for AG results. You may be right. I will have to check that out and get back. Maybe these models will then show decreasing gain as the radials drop.
Again, CMC was not considered by me since the model had no mast or feed line. However, I just made two simple models using my model above that has 3 horizontal radials.
I added a mast and renamed the file to (SD 3HR 18')
I then took the model and lowered the radials 60 degrees. I named it (SD 3-60dR 18')
Below are the models to compare the currents visually in the antenna view. I also attached the beginning and ending portions of the Tabular Segments Report that shows us the current distribution per segment for wire #5, the mast.
The wire has 108 segments and is a long report, so I captured the top and bottom portions showing about 40 segments of wire #5 for each model. So, according to this model the magnitude of amperage values for both top and bottom on the mast for the slanted down radial model are about 30% less that my horizontal model shows. So, this shows me the horizontal radials do not necessarily do a better job of minimizing CMC vs slated down radials in this case. Maybe you could recheck your results and let me know.
Again, we can also see a modest difference in the currents in the Eznec antenna view. The red line for currents on the mast is closer to the radiator, less magnitude, for the slanted radial model.
As you noted, the difference in angle changes the electrical length of the two models at resonance and that showed up during my tuning the model to resonance...as noted in attached antenna view for wire #1 noted at the bottom of each model.
