Thanks, everyone, for too many good inputs to list here. A lot of good ideas, both for experimental approaches and for the final configuration. At least for experimental purposes, I will go with the preamp in the shack and, assuming that my feedline is not quiet, significant improvements in management of common mode currents. One correspondent advocated transformer coupling instead of common mode chokes, and I'll need to correspond further with him on that, because I don't understand quite how it would work.
73, Pete N4ZR The World Contest Station Database, updated daily at www.conteststations.com The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com, spots at telnet.reversebeacon.net, port 7000 and arcluster.reversebeacon.net, port 7000 _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK