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Old May 10th 07, 05:28 PM posted to rec.radio.amateur.antenna
dykesc dykesc is offline
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First recorded activity by RadioBanter: Apr 2007
Posts: 53
Default OCF Sloping Dipole Txmsn Line Input Resistance Measurement

I just aquired an MFJ 259b analyzer. I'm using it to measure the
impedance at the input of the 300 ohm twin lead I have feeding a
sloping off center fed dipole. I measured 75 -j236 at 3.94 Mhz. When i
reverse the txmsn line leads where they connect to the 259b I get 175 -
j237. Does anyone have an explanation as to why the resistance value
changes simply by reversing the way the txsmsn line is attached to the
analyzer? I have repeated this numerous times, attaching and
reattaching always with very near the same results. Does the fact that
the antenna has unequal leg lengths somehow explain this? If it
matters, there is a 1:1 current balun between the txmsn line and the
antenna feedpoints.