For more details, and complete story about practical experience and comments please go to G7CNF web pages <a href="http://g7cnf.me.uk/EF_Duo.htm">http://g7cnf.me.uk/EF_Duo.htm</a> Several other DUO BAND designs were made, such as 6+7 and 7+8 elements but those will not be posted on the web.