> IMHO you are much better using a ballanced tuner with an UNUN on the > transmitter side.
http://www.w8ji.com/tuner_baluns.htm Apparently the balun's action was never fully thought through before articles suggesting baluns on tuner inputs were published. Everyone just went with off-the-cuff first impressions. Moving a balun to the tuner input works best if the tuner already did not need a balun in the first place. :-) There are balanced tuner tests on this page at the bottom: http://www.w8ji.com/balun_test.htm This shows a 1:1 current balun of good design on the tuner output is every bit as effective as a commercial "balanced" tuner, the E.F. Johnson KW Matchbox. It also shows how a 4:1 "current" balun on a single core (from "Baluns and UNUN's"), which is actually sold commercially as a balun and used in some high-end tuners, is not a balun at all! A single core 4:1 current balun will actually force a system into gross unbalance! I have a friend with a high-dollar motor-driven autotuner who had incurable RFI in his house on various bands with high power. He altered the feedline length, moved things around, and added grounds without success. When we looked at his tuner, it had a single core 4:1 current balun. Rewinding the same core to a 1:1 current balun cured his problems entirely. 73 Tom _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
