As Reg once noted, you could measure Zo with your ohmmeter in an
infinite line.

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It would not be a steady reading on the ohmeter. It would be a quick
deflection followed by a slower subsidence.

Zo of real lines is a function of frequency. As frequency decreases Zo
increases and becomes more reactive ultimately approaching -45 degrees.
This affects in a complex manner the behaviour of the ohmeter pointer.

The ohmeter reading changes from an initial low value to a higher value
versus time. The actual values and time taken depend on Zo and on the
voltmeter resistance. The final value is never achieved just as the final
voltage across a capacitor being charged up via a resistor is never
achieved.

To calculate input resistance versus time as recorded on the ohmeter
requires a large amount of calculation using Heaviside's operational
calculus.

An infinite series of complicated terms is involved. This type of
calculation on transmission lines must have been amongst the very first
carried out by the young Heaviside himself round about 1872. It is closely
related to the distortion of keying waveshapes along telegraph cables.
Imagine the pleasure he experienced, using his own calculus, as he with his
sliderule produced the very first sets of figures and graphs describing the
waveshapes. It is still related to distortion of digital signals in this
modern electronic age but now we have oscilloscopes.
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Reg, G4FGQ