So my question at this moment is - which is the
proper method for me to calculate the proper
delay line length to properly phase the two
dissimilar SteppIR yagis?
This is not meant to be a snarky or otherwise "cute" response. Just more
like a reality check. The answer is:
Feed them with equal length feedlines and see how they play. If you like
the way they work, then you're done. I suspect you will like the way that
they work and I also suspect changing one feedline length by as much as 8
feet would not affect your overall conclusion.
Neither the WX0B formula or the WN9O formula accounts for imbalance caused
by the dissimilar feedpoints (even if the feedpoints were identical in every
other respect, one is still closer to the ground than the other) - meaning
there are undoubtedly unknowns in the mix which from the seat-of-my-pants
means it may largely be an academic question, likely trumped by actual
implementation.
Get on the air and work guys. I bet you work more guys with two antennas at
you disposal than just one antenna, and I bet when you do
top-bottom-bip-bop* tests you will find some times when some stations are
lounder under some of those four conditions. I suspect this would be the
same conclusion whether your coaxes are the same length or different lengths
by 4 feet or 8 feet.
This is what I would do anyway, and what I have found to be true in the past
when stacking dissimilar tribanders in real life™.
73 - Mark, N5OT
* Top antenna alone, bottom antenna alone, both antennas in phase, both
antennas out of phase
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