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Henry, I think the thin radiator effect would only matter in the lower part of the antenna since it forms a coaxial cone. I noticed that your wire lengths that form the loop are much smaller then the four 24 inch loop sections used on the Sigma design. I wonder if when you increase the diameter of the main radiator if you should also increase the lengths of wires 11, 12, 13, and 14 to around 24 inches. This may balance the effect out. I also think you will have to shorten wires 2, 3, 4, and 5 from 122 inches to 106.5 inches. I'm not sure if you tried this but it would help simulate the impedance we see with the thin wire radiator. When the inside conductors diameter increases, you have to increase the outside diameter to compensate. There may be more going on here then just that, but it's a start. I also agree the antenna definitely performs like a real collinear! The two separate currents generated by the coaxial cone base and the top radiator are clearly in phase with each other.

<blockquote data-quote="Shockwave" data-source="post: 210915" data-attributes="member: 10882"><p>Henry, I think the thin radiator effect would only matter in the lower part of the antenna since it forms a coaxial cone. I noticed that your wire lengths that form the loop are much smaller then the four 24 inch loop sections used on the Sigma design. I wonder if when you increase the diameter of the main radiator if you should also increase the lengths of wires 11, 12, 13, and 14 to around 24 inches. This may balance the effect out. I also think you will have to shorten wires 2, 3, 4, and 5 from 122 inches to 106.5 inches. I&#039;m not sure if you tried this but it would help simulate the impedance we see with the thin wire radiator. When the inside conductors diameter increases, you have to increase the outside diameter to compensate. There may be more going on here then just that, but it&#039;s a start. I also agree the antenna definitely performs like a real collinear! The two separate currents generated by the coaxial cone base and the top radiator are clearly in phase with each other.</p></blockquote><p></p>

[QUOTE="Shockwave, post: 210915, member: 10882"] Henry, I think the thin radiator effect would only matter in the lower part of the antenna since it forms a coaxial cone. I noticed that your wire lengths that form the loop are much smaller then the four 24 inch loop sections used on the Sigma design. I wonder if when you increase the diameter of the main radiator if you should also increase the lengths of wires 11, 12, 13, and 14 to around 24 inches. This may balance the effect out. I also think you will have to shorten wires 2, 3, 4, and 5 from 122 inches to 106.5 inches. I'm not sure if you tried this but it would help simulate the impedance we see with the thin wire radiator. When the inside conductors diameter increases, you have to increase the outside diameter to compensate. There may be more going on here then just that, but it's a start. I also agree the antenna definitely performs like a real collinear! The two separate currents generated by the coaxial cone base and the top radiator are clearly in phase with each other. [/QUOTE]

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