Measured SWR on 40 meter end fed dipole (with 9:1 unun at fed end and 1:1 unun at ground level) ranges from 7.5 to 8.3. Sometimes the tuner does not reach "Success" and just shows Mem but tuned swr is 2-2.5. When I return to a successfully tuned frequency, sometimes the swr is above 3 (pegged on flex SWR meter) and I have to retune. My coax is grounded at a grounding rod before passing through a conduit to the basement shack. Length is about 18 ft from fed end 9:1 unun to 1:1 unun. 1:1 unun is to curb rf on coax shield since it is the counterpoise for the antenna. Also about 18 ft from the 1:1 unun and ground rod to the radio. Cannot reduce the last 18 ft any more. Any thoughts on cause/cure? System tunes up well on other bands which have lower SWR for this end fed antenna. Coax switch serves as ground point for station. Thanks for any comments!