Alan Taylor wrote:
I should have mentioned the trees are in position for a broadside array to
fire in the (two) directions I need.

A horizontal 66 ft. dipole fed with ladder-line would
work for 40m-10m and give you some gain over a 1/2WL
dipole on 17m where it would be an Extended Double
Zepp. EZNEC says feeding it with 9 feet of 450 ohm
ladder-line and then coax the rest of the way gives
a pretty good single-band match on 17m.
--
73, Cecil http://www.w5dxp.com