W6RMK wrote:
>Where mismatched phasing lines will bite you is:
Jim, none of your examples really apply
to the case under discussion. 10 degrees phase
difference is simply insignificant in a Yagi stack.
I just checked the +/- 10 degree case and it only
made a 0.01 dB difference in F/B...similar to the
difference seen in forward gain. Of course I did
match my lines for 0, but the point is that slight
differences are not critical (which I believe is
germane to K9KL's original question).
>c) Mismatched phasing lines will put the main lobe at
different take off angles than you expect.
Sometimes we want this (i.e. BOP for high
angle skewing). In this case we are talking LARGE
differences (180 degrees...not 10). I recall modeling
90 degrees and decided it was not worth pursuing. If
one can manage a 3-stack, I feel this is a better
solution for TOA coverage than a 2-stack with BIP/BOP.
I also like the ability to beam in 3 different
directions sometimes.
This discussion is following usual Internet
protocol, going from 0 to 10 to 45 to 90 to 180 degrees,
so I guess it's time to go full circle back to 360...
sorry I couldn't resist! :-)
73, Bill W4ZV
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