Hey Bob or SW how about a little description of what we're looking at. This looks very similar to what Henry sent Shockwave originally. Henry indicated to me that the radiator in that case was only 24' feet long. I didn't get how that was possible, especially in light of the fact that HomerBB told us that his 5/8 wave length antenna with radials slanted up would not match at all in a similar configuration.
No body is even speculating what is going on with any of these models and I don't get much just looking at pictures.
I was waiting on Henry to redo his model of the Vector 4000 with more accurate dimensions before saying anything, thinking maybe a better fix on the measurements would show something to compare with his 24' foot model.
Now we get this model from SW with no description of what it is, and it looks about the same as the first model Henry made. The only thing I can tell is the frequencies are about 20 channels different and the gains shown are basically the same values. If SW tweaked the model that Henry sent him to make the radiator longer and whatever else he did to make it more accurate, then it didn't make much difference in gain and the frequency went the wrong direction for adding length to a radiating element. If this is the best example of the highest gain model from SW, then we don't need a 28', 29', or a 31' foot radiator. I don't get it.
HomerBB modified his 5/8 wave the other day to a Vector style and he indicated that the antenna would not tune until he added the necessary length a bit longer than 27' feet---and maybe that makes sense. However, I thought it was strange when considering that Henry's model at 24' seemed to show good gain and an almost perfect feed point condition at 34.6 + j 0.5289 ohms---a condition with a potential for a good gamma match. The match he showed with the 24' radiator could be direct fed like we might expect with a resonant 1/4 wave radiator.
HomerBB also said his match only went below 1.5:1 SWR when he added the hoop and I don't get that either. Seems I recall the patent saying using full 1/4 wave radials would work fine, but adding the hoop and making the radials a bit shorter also improved bandwidth. I did have a thought that maybe Homer didn't look up and down frequency much to see what was going on elsewhere. But, could this length thing be another point for confusion?
Homer asked for help in understanding of what he was seeing, so I'm inclined to believe he experienced what he described, but I don't understand it---and for sure if I consider how this all is relative to the Eznec models we've seen so far.
We all know how complicated the Sigma 4 design is and thus far there is nothing made clear here until we know what we are looking at. Just keep up the good work and maybe this will clear up soon.
A while back I complained in a previous post I was confused, "I'M STILL CONFUSED."
Here is what Henry sent me stating it was the file that he originally sent SW.
No body is even speculating what is going on with any of these models and I don't get much just looking at pictures.
I was waiting on Henry to redo his model of the Vector 4000 with more accurate dimensions before saying anything, thinking maybe a better fix on the measurements would show something to compare with his 24' foot model.
Now we get this model from SW with no description of what it is, and it looks about the same as the first model Henry made. The only thing I can tell is the frequencies are about 20 channels different and the gains shown are basically the same values. If SW tweaked the model that Henry sent him to make the radiator longer and whatever else he did to make it more accurate, then it didn't make much difference in gain and the frequency went the wrong direction for adding length to a radiating element. If this is the best example of the highest gain model from SW, then we don't need a 28', 29', or a 31' foot radiator. I don't get it.
HomerBB modified his 5/8 wave the other day to a Vector style and he indicated that the antenna would not tune until he added the necessary length a bit longer than 27' feet---and maybe that makes sense. However, I thought it was strange when considering that Henry's model at 24' seemed to show good gain and an almost perfect feed point condition at 34.6 + j 0.5289 ohms---a condition with a potential for a good gamma match. The match he showed with the 24' radiator could be direct fed like we might expect with a resonant 1/4 wave radiator.
HomerBB also said his match only went below 1.5:1 SWR when he added the hoop and I don't get that either. Seems I recall the patent saying using full 1/4 wave radials would work fine, but adding the hoop and making the radials a bit shorter also improved bandwidth. I did have a thought that maybe Homer didn't look up and down frequency much to see what was going on elsewhere. But, could this length thing be another point for confusion?
Homer asked for help in understanding of what he was seeing, so I'm inclined to believe he experienced what he described, but I don't understand it---and for sure if I consider how this all is relative to the Eznec models we've seen so far.
We all know how complicated the Sigma 4 design is and thus far there is nothing made clear here until we know what we are looking at. Just keep up the good work and maybe this will clear up soon.
A while back I complained in a previous post I was confused, "I'M STILL CONFUSED."
Here is what Henry sent me stating it was the file that he originally sent SW.
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