James barrett wrote:
My naive understanding was that I could hang up a 100ft dipole and use
a tuner to transmit on all bands. What bands can I reasonable expect
to transmit on using a 100ft dipole and a tuner?

Make that "all HF bands". 160m is not an HF band.
Also, the dipole must be fed with parallel-line,
ideally open-wire line, for all HF band operation.

W2DU's rule-of-thumb is that a dipole should be
at least 3/8 wavelength on the lowest frequency
of operation.

A 100 ft. dipole can usually be used on 160m,
not as a dipole, but as a Marconi-style fed
system with the transmission line conductors
shorted together and fed against a good radial
ground system.
--
73, Cecil http://www.w5dxp.com