Hello Bob !
a balun is absolutely the wrong thing to use. It supposes that both
sides on the balanced side have the same impedance to ground. That
definitely is not the case with a vertical and a ground system. The
impedance you want to match is a composed one, simplified its the
radiation resistance of the vertical and the ground loss resistance
together. By using a balun output which equals the impdance of Your
shortened vertical, You CANNOT eliminate the loss in the ground
resistance. Further i doubt the measurments on the primary side of the
balun. It is very likely done with a mter that does not have good
discrimination or the loss in the core makes it look good. None of the
AM stations ever used a balun on the output side with vertical
antennas.And that for a reason . See " radio antenna engineering" by
Laport . This is the download site , its free :
http://snulbug.mtview.ca.us/books/RadioAntennaEngineering/
after going thru this, all ur questions will be answered
wolf df2py
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