As you surmised, Ed, the 43 ft length is used so that the SWR isn't real
terrible on the more popular bands. At 43 ft you will get compromise
performance on 80, good performance on 40, 30 and 20, and poor DX
performance on 17, 15, 12, 10. 40 30 and 20 are best because you will
actually have some gain over a 1/4 WL vertical and nice low angle DX
performance. All this is dependent on your ground radial system however.
Plan on 32 or more radials for reasonable performance.
I use this system here. The vertical 43 ft element is a wire supported by a
SpiderBeam fiberglas pole. Easy to put up and take down over the radial
field, since I'm in an antenna restricted neighborhood. I've been quite
pleased with the performance at 100W. I use a remote tuner (CG-3000) at the
base and it makes for a very convenient set-up. Of course this isn't as
easily accomplished at the higher power levels you want to run. I also have
a coaxial current choke in the feedline.
Bottom line is that it will work somewhat on all bands and work well on 3
bands, but only if you put down a good radial system and, in your case, pay
attention to feedline losses.
73 Craig AC0DS
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