I have seen two commercial antennas advertised that are each 43 feet tall,
and have no traps/stubs, etc.
There appears to be a 4:1 balun at the feedpoint. Mentioned, is the
requirement to have a tuner at the driving end of the feedline, and max
VSWRs in the 4:1 range.

Playing around a bit with EZNEC, the feedpoint impedances over the
operating range have some large swings. Can anyone shed light on how
effective the antenna should be?
Wayne
W5GIE