Hi Tom,
My G5RV is only about fifteen feet off the ground.  It was a 
temporary installation ten years ago!!  The twin lead isn't vertical 
and the coax doubles back on itself and the whole thing shouldn't 
work.  But it does, not too well, but work it does from ten through 
75.  I am using a TS850 and the tuner brings the antenna close enough 
to make the transceiver happy.  How is your ground?  That could 
adversely affect either antenna.
Good luck and look for you on the air.
Pat, K9JAU At 01:22 AM 4/2/2006, you wrote:
>I am having trouble getting on the air. I have a G5RV at only about 15
>feet, and a CushCraft R7 with the bottom at about 12 feet. I can get a
>decent SWR on 10 meters, but as I go down the bands the SWR gets worse
>until at 80m. it is about 9:1. The transciever, a Kenwood 850, works fine
>against a dummy load. The cox cables are fine. I even swapped in a new
>g5rv. I could get either antenna higher with guyed masts, but think one of
>them should work better without doing a lot of elevating. Any ideas?
>Tom Karnes K6FUN