Placing those big ugly baluns or big cores should be reserved for wire
LPDA's, not on a LPDA made of structural aluminum, IE: tubing.
An "Infinite Balun" is widely used on these as its a clean and efficient
method to fed an LPDA.
All Military Planar and Pyramidal LPDA's use this simple feed method.
Run coax, IE: UT-141, RG-141, inside the tubing and connect the outer
shield to one boom and the center conductor to the opposite boom.
This can be done by solder lugs, or plugs, in each tube end.
The spacing of the twin booms can also be used to adjust the VSWR if need.
Keep the twin booms isolated from each other and the mast,
Tom W3FRG
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