David -- Suggest you take a look at the attached paper by Jim Brown. I live in a fairly dense suburb where every house (including mine) has all the latest RF noise-makers. Following Brown's suggestions, I've put large 31-material clamp-on ferrites on both ends of my receive antenna feedlines (and sometimes one in the middle), and it makes a very clear difference.
Regards, Art Delibert, KB3FJO ________________________________ From: Topband <topband-boun...@contesting.com> on behalf of Rodman, David <rod...@buffalo.edu> Sent: Tuesday, October 23, 2018 6:41 AM To: topband@contesting.com Subject: Topband: Common Mode I purchased some 7mm dia snap on cores for RG6 receive antenna coax. I was wondering if anyone had any experience or suggestion as to how many one would place on each lead. The feed lines are about 50% on the ground with grass growing over or buried 2-3". The lengths vary from 300' to 750', depending on the antenna I am using for listening. I was planning to place them inside the station. I have nothing now and thought this would be acceptable versus removing connectors and placing beads? Thank you. --- David J Rodman MD Assistant Clinical Professor Department of Ophthalmology SUNY/Buffalo Office 716-857-8654 _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector