W8JI also describes one and how to calibrate it. http://w8ji.com/building_a_current_meter.htm Eric KE6US On Tue,8/9/2016 1:56 PM, MaverickNH wrote: >> Just wondering - short of +/- RF Burns and Audible Noice, can one >> readily >> detect/measure Common Mode Current on a coax antenna feedline? >