Contact Bob at Balun Designs for all your balun needs. If you have an antenna, Bob has a balun or choke for it. Bob manufactures high quality baluns and ununs for Amateur Radio and commercial applications based on the researched and tested designs of Dr. Jerry Sevick, W2FMI. Bobs site also shows the AIM-4170 analizer plot diagrams of their baluns. We want to thank Bob for sharing the info needed to build our own balun for our home install antenna package.