On Dec 7, 1:00 pm, Cecil Moore wrote:
Keith Dysart wrote:
If the 100 ohm line was only 5 degrees long, how
long would the 600 ohm line have to be to obtain
0 ohms at the input?

-jcot(5) = -j11.43 normalized to Z0=100 ohms

-j100(11.43) = -j1143 ohms at the junction

-j1143/600 = -j1.905 normalized to Z0=600 ohms

arctan(1.905) = 62.3 degrees of Z0=600 ohm line

Would the phase shift at the junction still be
36.6 degrees?

The new phase shift would be 90-5-62.3 = 22.7 deg.

62.3 + 5 + 22.7 = 90 degrees

So sometimes a 600 to 100 ohm discontinuity
produces a 36.6 degree phase shift and sometimes
it produces a 22.7 degree phase shift (and probably
any value in between).

I suggest that "work[ing] up the phasor diagrams of
the component voltages (or currents) at the junction
where rho = (600-100)/(600+100) = 0.7143" will
not be useful for predicting the phase shift.

....Keith