The point that keeps rattling around in my head when I read these discussions
is the assumption of the bip-bop folks that inserting a half wave of coax to
one feedline creates a 180 phase shift between the two antennas... Given that
the two antennas are coupling which changes their impedence and reactance, and
given the two antennas are different heights above ground which changes their
impedence and reactance, I doubt that the resultant phase difference is the
expected 180 degrees...
While there will obviously be a difference in the pattern with the inserted
coax on one line it is not likely to be the expected pattern...
Perhaps one of our bip-bop operators on this list could insert sampling
transformers at the feedpoints and run the signals back to an oscilloscope and
enlighten us with pictures... Or, one of our resident electronic cognoscenti
(roy, al, tom, etc.) could do the analysis... It may be that bip-bop patterns
could be improved with a simple change in the length of the inserted delay
line...
denny
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