Steve, your right, it didn't last long here! The main problem seems to
be that the elements can't flex in the horizontal direction without
compressing one part of the linear resonator and extending the other.
This is a problem on the 40m shortened Yagis, also.
To tighten the cross straps, deforming them is only a somewhat temporary
fix, but putting a stainless washer on each side, under the screw head
and nut, might add some backbone to the connection. I had given a lot
of though to using flexible braid, insulated, as cross-straps that would
allow the sideways flexing of the elements.
Another problem was that the traps filled up with water in a wind/rain
storm. Some folks went as far as slotting the outer capacitor tubes so
the water would drip right back out. Transmitting with a wet cap will
soon fry the end caps, so don't try to dry the wet antenna out with RF!
Another thing I've daydreamed about is putting the capacitors inside the
elements, maybe using foam to center the center conductor. I think the
KT34 worked well, but it was always hard to tell if it was ok or not, and
when I switched to a 205BA the difference was noticeable. There's no
perfect solution, and dB-hours rather than just dB might favor a smaller
but more robust tribander. The perfect tribander is
not yet invented...73, Dave W6QHS
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