Bart Rowlett wrote:
The relationship is correct for all frequencies and standing wave ratios
as long as the correct frequency dependent values of transmission line
parameters are used.

Here's the equation that Ramo and Whinnery says is an approximation
for low-loss lines.

Z0 = SQRT(L/C)[1 + j(G/2wC - R/2wL)]

If G = C * R / L then Z0 = SQRT(L/C)

So why did Ramo and Whinnery say it is an approximation for low-loss
lines?
--
73, Cecil http://www.qsl.net/w5dxp