I am trying to use a 259B to measure the impedance of a short vertical for a
receiving array. I have an FM station about 1 mile away that I'm pretty
sure is giving me erroneous readings, I've had this trouble before on 40 and
80 meters. I've tried the MFJ filter but it's notch is for the AM band and
it doesn't seem to help much. I have used an Ice 419 selectable bandpass
filter with the 259B and the results seem in line but I still worry that the
unit skews the readings on the 259B somewhat. In using the 259B with no
filter, I do get a deflection on the swr meter when I go to the frequency
counter mode and it goes to 0 when using either the MFJ filter or the 419.
I believe that is the correct check of whether you have interference
problems.
My readings with the 259B and no filter show a resonance point but with very
high R values when I believe they should be low and are low when using the
419.
I can borrow a CIA-HF and/or Cablemate but was wondering if anyone has seen
one of those units better reject the type of interference I am seeing?
Mike W9RE
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