Ed wrote:
Thanks, Irv. Possibly workable for me, but the threaded end needs good
RF continuity to the 1/2" tube end, which will be soldered to a helical
winding running up the fiberglass rod.

Connect the helical winding to a 3/8" automotive lug and slip it over
the 3/8" threaded section.
--
73, Cecil http://www.qsl.net/w5dxp