At 01:53 PM 6/14/2007, Tom Rauch wrote:
> > Anything is possible, of course, but coax would have to be
> > pretty awful for
> > enough field from the differential signal to cause
> > significant heating.
>"Unlikely" isn't strong enough, it would be impossible.
>I can buy the cheapest radio shack coax, the type that you
>can see through the shield to the center dielectric, and it
>is nearly impossible to measure the leakage through that
>shield unless I use special equipment.
>Let's not obsess about things that don't mean anything. Let
>the Audio-phools and CBers worry about those shields.
I suspect that a crummy shield would have a larger effect on IR
losses than on anything else. But, since the surface area of the
shield is so much larger than the center conductor, I would think
that the center conductor dominates. For foamed dielectric, I think
75 ohm cable is around 5:1 diameter ratio, so the shield only
contributes 15-20% of the loss. For 50 ohm cable, the ratio is
smaller, so the shield loss would be more important.
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