My KT34XA which has always worked the least on 15 now is busted.
The beam is 9 feet below the 2 el cushcraft 40 and for years the 40 worked
almost as well as the XA on 15 although a runer is needed. Since I raised
the tower
two weeks ago the KT34XA has a 2.5 to 1 SWR and pointing the beam at say VK
the signal actually goes down. With the beam off 50 degrees its close but
almost never equal
to the 40. The 40 acts like a directive beam although the 15 F/B is only a
few DB.
The other antenna is a 12 meter X beam 5.5 feet below the XA. It now has a
1.2 to 1 swr whereas before it was
1.8 to 1 so maybe this antenna is interacting. I use the W9PNE method of
wire backs so the elements are longer
than a straight 12 meter antenna ( the driven element is over 20' long or
close to 15 meter length). The X beam works great
as 9M2AX and 0M2XA came back to first calls ...not bad for an antenna with
4.5Dbd.
Any ideas of how to figure out what is interacting? I think K6STI had a
program for interactions, but he closed for awhile due to
pirated copies of his software.
For now I am on my 40 meter beam on 15.
73 Dave K4JRB
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