> Indeed, phase errors of tens of degrees aren't going to
have a huge effect,
> however, a transmission line length change of 30 degrees
might have a
> radiated phase change much different. The reason is that
you're not just
> using the coax as a delay line, because neither end is a
well matched load.
> (Even if the individual antenna is a nice 50 ohm load when
tested by
> itself.) The impedance transforming effect also comes into
play. At the
> junction point, neither coax is going to present a nice 50
ohms, but both
> will present some reactive impedance, likely quite
different, so the
> currents will distribute unevenly.
Unless I'm mistaken, the peak phase error caused by a line
mismatch occurs when the line is an odd multiple of 1/8th
wavelength. Phase error is zero at any multiple of 1/4 wl,
even or odd.
Correct me if that is wrong, but it seems I recall that from
past phase analysis.
73 Tom
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