I havent experimented on top band but I have tried elevated radials on 80M ¼ verticals. I had one in Houston Texas that worked wonderfully elevated 8 radials at about 10 ft. Ground conductivity in Houston was about as good as anywhere in the US. I tried doing the same thing at 2 different QTHs in Vermont and both were very disappointing. I gave up on elevated radials for 80 and 160M.
My experience has been that ground conductivity matters for a small number of elevated radials. I have been much happier with 48 ¼ wave ground radials. Ed N1UR _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector