[TowerTalk] Balun question shield leakage

[Jim Lux]

At 05:12 PM 6/14/2007, Jim Brown wrote:
>On Thu, 14 Jun 2007 16:27:38 -0700, Jim Lux wrote:
>
> >I suspect that a crummy shield would have a larger effect on IR
> >losses than on anything else.
>
>It has been observed (by N6BV and others) that in most coax, losses
>are primarily IsquaredR below about 500 MHz, and primarily in the
>dielectric above that frequency. Obviously, that's a broad
>generalization, and varies from one cable to another.

So, for "cable TV" kinds of applications, the extra resistivity from 
using an aluminum shield probably isn't as big a deal: 75 ohms makes 
larger diameter ratio, and dielectric losses starting to be a bigger fraction.


>Jim Brown K9YC
>
>
>
>_______________________________________________
>
>
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk at contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk