And there is an excellent picture of the installation for common mode - used at Clifton - in this article. http://www.cliftonlaboratories.com/vlf_signals_with_improved_setup.htm Lots of great help here ! 73 Mitch On 2013-01-24, at 5:05 PM, Laurence KL1 X wrote: > Wonder what type he uses- J's or maybe a lower mu (77's) a wide-band non res compromise? >