"craigm" wrote in message
...
m II wrote:

Frank Dresser wrote:

The
resistance of a long run of transmission line can be significant, and
would be infinite over a infinate length.


Wouldn't the DC resistance between a coax sheath and the inner conductor
actually DECREASE as length increased? An infinitely long cable should
have ZERO resistance between the two, as the dielectric resembles an
infinite number of very high value resistors in parallel. Paralleling
resistors lowers total R.




mike


Both center conductor and shield have series resistance.

craigm


And real world dielectrics are less lossy at DC than real world conductors.
So, the conductor resistance would dominate the conductor resistance -
dielectric conductance ratio over a very long run.

Any ohmmeter will measure the resistance of a few thousand feet of
transmission line. But it would take a sensitive meter at much higher
voltage to read the slight leakage current in that same amount of line.

But I don't know if that would be true at all temperatures, though.

Frank Dresser