Topband: center-tapped common mode choke

[Lee K7TJR]

  I have watched this thread with great interest along with the
 8 element array discussion. I am curious as to how well a
 simple separated winding or even bifilar for that matter,
 transformer would work compared to the larger common
 mode chokes. I have very successfully used broadband
 transformers on each end of the nearly 1/2 wave resonant
 connecting lines on my 8 element arrays for common mode
 reduction. Very similar to a Beverage antenna needing
 separate windings.
     Even if the active antenna requires carrying DC on the coax,
 a transformer can be paralleled with high Q inductors,
 preserving the common mode rejection. Greg, ZL3IX
 published his schematic showing this technique in 2004
 which he used in his remote 8 element RX array.
     Some of the enhanced techniques used by W8JI for
 high common mode rejection transformers on flag and loop
 antennas should even help with a transformer inserted in a
 receiver feedline.
  Lee  K7TJR  OR