Hi Luc,
I've assembled several of these antennas and never found a problem. I would suspect assembly error; page 7 of the manual has all the dimensions to verify proper assembly. there are four columns of figures.
The leftmost column is the distance from the end of the boom to that particular element, while the rightmost column is the length of that element. Those 2 columns are for the horizontal elements.
The middle two columns are the measurements for the vertical plane elements. Again the "middle-left" column is the distance from the end of the boom, while the "middle-right" column is the element length.
The most likely element(s) to miss mounting are the one(s) that are mounted through the balun or tight against the polarity switcher.
If you don't have the manual let me know and I will get a copy to you.
73 Don -VE1AOE-
I just assemble and "old" oscar 1 era KLM 2M 22C beam over the week end to
ended stuck up with one element and no matching pre drilled hole
in the boom tube. Did anyone recollect if KLM ever missed pre drilled hole
in their workmanship? My assembly was on the side of a bit hurry
and i will have to recheck al the measurements but with the pre drilled
bolt holes boom section attachment it is hard to make mistakes but
we never know!
Thank's for your inputs?