Do you have an antenna analyzer that measures the inductive reactance? That would be the easiest approach. Jim - WS6X
Today's Date: Sun, 10 Dec 2017 16:05:53 -0500 From: "Gary Smith" <g...@ka1j.com> I just installed a replacement wire for the 160 sloper. I made it 129' as was the earlier one that came down in the winds. I have to use a spud gun to get fishing line over the tree tops and where the spud lands, I connect the wire to the eye fastener & reel it to the radial plate. This time I had to use a different tree as the earlier one came down in the last hurricane. Now it is resonant at 1.785 and it is not a problem at the lower end of 160 but higher up it is. My problem is compounded in that I also use this antenna for 10M, 12M and the upper part of 15M. I need to shorten it for use on these as well. It is too far away to shorten the wire and solder a new eye on it and now it is too cold to play with it on the tree (have difficulty walking right now). So being too long, capacitance at the feed point might be my best answer. I have several fixed vacuum & doorknob capacitors of small pF to choose from that I can put in line. Is there a formula that I might plug data into to come up with the needed pF? Thanks & 73, Gary KA1J _________________ Topband Reflector Archives - http://www.contesting.com/_topband