[TowerTalk] Fields and coax

[Roger Parsons]

Tom's post is exactly correct except to a
nit-picker...

I hate to disagree Tom, but there is always an
external field even with perfectly shielded coaxial
cable. This is because the outer conductor has a
finite thickness, and therefore different internal and
external diameters. I could probably drag up the maths
from long forgotten recesses of the mind if really
forced to.....

I would not wish to mislead anyone - the effect is
extremely small with properly designed cables, and for
nearly all practical purposes can be ignored. This is
an entirely different mechanism from that
intentionally used in 'leaky feeder' cables and
unintentionally used in badly designed coax. 

73 Roger
VE3ZI



	
	
		
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