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[QUOTE=&quot;Piggie, post: 20855, member: 2941&quot;]I love Devil's Advocate discussion as makes the brain work, broadens horizons, etc.&nbsp;&nbsp; I also love when things are challenged by valid antenna facts. I know you are much more into &quot;gizmo&quot; antenna than I, but you know a lot of antenna theory and make talking about them fun.&nbsp; What bugs me is when all I am quoted is look at my picture and I live x miles away, which means nothing except it works for them. Well both the 751 and the 7000 have the same boom, so that is equal. And yes the 751 has an additional high band director element.&nbsp; But some say cramming in a director on an already crowded boom is diminishing return and might even hurt the gain but help some on beam width. I expanded the PDF on the 7000R and it appears all elements that look high band (2 directors and a reflector) are passive.&nbsp; On VHF it appears the longer low band looking elements are driven.&nbsp; They may be playing off a third harmonic or just like the old 4228 resonated on VHF because the screen did and it was passive.&nbsp; Coupling into a driven element can be odd and not apparent.&nbsp;&nbsp; So going on that, the 7000R might have more than 3 elements on high band with parts of the longer two adding up to be close to the equivalent of another element for high band. I can't get away from the fact the YA-6713 is 50 inches long. It is fairly simple to analyze as it has 3 directors and a reflector passive.&nbsp; Then 2 driven elements that on any the ends of the band only one works and toward the middle both work.&nbsp;&nbsp; It has about 7 db gain, that matches all my history of building and playing this wide spaced yagis on 2 meters and commercial linking. Devils advocate the other way, I still say the 751 only has about 5 db of gain, maybe a little more but just adding a director to the same boom as a 700R won't give 2 more db, and probably .5 at best. Which would I bet works better on high band? RCA ANT751 would get my money.&nbsp; But can you tell it inside on the CECB?&nbsp; Or more so I would say you would need a good test range to see the clear winner on paper, though we both know the 751 should win.[/QUOTE]

[QUOTE="Piggie, post: 20855, member: 2941"]I love Devil's Advocate discussion as makes the brain work, broadens horizons, etc. I also love when things are challenged by valid antenna facts. I know you are much more into "gizmo" antenna than I, but you know a lot of antenna theory and make talking about them fun. What bugs me is when all I am quoted is look at my picture and I live x miles away, which means nothing except it works for them. Well both the 751 and the 7000 have the same boom, so that is equal. And yes the 751 has an additional high band director element. But some say cramming in a director on an already crowded boom is diminishing return and might even hurt the gain but help some on beam width. I expanded the PDF on the 7000R and it appears all elements that look high band (2 directors and a reflector) are passive. On VHF it appears the longer low band looking elements are driven. They may be playing off a third harmonic or just like the old 4228 resonated on VHF because the screen did and it was passive. Coupling into a driven element can be odd and not apparent. So going on that, the 7000R might have more than 3 elements on high band with parts of the longer two adding up to be close to the equivalent of another element for high band. I can't get away from the fact the YA-6713 is 50 inches long. It is fairly simple to analyze as it has 3 directors and a reflector passive. Then 2 driven elements that on any the ends of the band only one works and toward the middle both work. It has about 7 db gain, that matches all my history of building and playing this wide spaced yagis on 2 meters and commercial linking. Devils advocate the other way, I still say the 751 only has about 5 db of gain, maybe a little more but just adding a director to the same boom as a 700R won't give 2 more db, and probably .5 at best. Which would I bet works better on high band? RCA ANT751 would get my money. But can you tell it inside on the CECB? Or more so I would say you would need a good test range to see the clear winner on paper, though we both know the 751 should win.[/QUOTE]

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