Tell me how to coax feed a dipole that works from 3.3 to 4.1 MHz and you
have my attention.

Probably wouldn't be practical for you.. Just offhand, I can think
of a way, but you'd have to run at least two set of dipoles, and
maybe even three, tied together in parallel. You would stagger
tune them one low, one middle, one high, and the SWR
plot should look about like a \/\/\/ . I've never tried using
three dipoles, but I've done it with two and having a W SWR
plot. That is one way you could have that range and use
coax feed. But like I say, probably would be a PIA with
it needing at least one center support and six tie off
points.
MK