Specifications
This is a horzontally polarized three Element Yagi. The bent Elements cause very little performance lose.
When you consider it is only 8ft. 5" wide and 7ft. 6" long and still has 6.2dbi gain and 20db front to back ratio.
And when you off center feed it you get a perfect
50 ohm match to coaxial cables.The SWR is less than 2to1 for 600khz.
Not bad for a Antenna that the neighbors don't even know exist.
The question
HOW MANY INCHES FROM THE CENTER OF THE DRIVEN ELEMENT IS THE FEED POINT?
Is not a simple one, each installation is different there is no set distance from the center. There is too many variables to consider the height above ground is one of them the gauge wire is another all objects that are within 16 feet is one more but there is a simple solution to this problem. If you make each end of the driven element adjustable where you can easily change the length then you can easily off center the feedpoint to the exact spot that gives you the 50 ohm match.
Remember that you want to keep the total length of the driven element 16 feet long so if you shorten one side by one inch you want to lengthen the other side by one inch this will maintain the 16ft. if you make the last 12" of each end of the element where you have a second wire that is wrapped around the element wire and it is also 12" inches long you will be able to lengthen or shorten that wire easily.
So one-half of the driven element would be seven feet long and the other half of the driven element would be 8 feet long and you would be able to lengthen the seven foot element up to 12" inches longer and you would be able to lengthen the eight foot element up to 12 inches longer once you get your perfect match all you have to do then is solder the sliding wire permanently to the element on each end.
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