Reg Edwards wrote:
It measures the MAGNITUDE of the reflection coefficient. It discards
the information which is contained in the phase angle of the
reflection coefficient. As a consequence the only use which can be
made of the magnitude is to calculate the SWR on an imaginary 50-ohm
line.

Reg, I dug up some calculations from sci.physics.electromag
from about a year ago that indicate one foot of 50 ohm coax
on each side of the Bird is enough to make the line real,
i.e. not imaginary, and that's a conservative estimate.
--
73, Cecil http://www.qsl.net/w5dxp