BIZ IDEA: Make an extremely lightweight & compact one with 2 or 3 elements (which maybe fits inside the telescoping pole made of roll wrapped fiberglass. Also, one could be made to raise on the multipole. (If I can figure out a way to clear the guy ropes.
This is the 2 elements of the portable yagi that Richard Kears showed me. It has a piece of pvc between the elements to hold them in place & it has a T-fitting so it fits on top of a pvc sectioned pole, much like the first one on this page.