The DUT is a 9m coax cable with open end.
The voltage V1 is shown in red, V2 in yellow, and V2-V1 in green.
Note that since the magnitude (=the absolute value) of the reflection coefficient is 1.0, the impedance Z=R+iX of the DUT is always pure imaginary, whatever the cable length is, and therefore the vectors V2 and Vr6 are always mutually orthogonal. In other words, the terminal point of the vector V2 is always on the circle, and the angle of V2 against V1 is half the angle of V2-V1 against V1.
You can see that the delay of V2 (yellow) against V1 (red) is 45nS, and the delay of V2-V1 (green) against V1 is 90nS, just twice the value as is expected. Since the period T is 524nS (f=1910kHz), these correspond to the angles of 30.9deg and 61.8deg, respectively.
Spinor Lab 