[TowerTalk] Coax loss. Has anybody measured it ?

[Jim Lux]

On 11/29/14, 10:36 AM, David Robbins wrote:
> You want some lossy coax?  I have a couple old rolls where both the center
> conductor and shield are nichrome.  VERY lossy stuff!
>
What would they use nichrome coax for? Some sort of test jig for heating?

For use in a refractory or corrosive environment? I think I've seen 
hastelloy or something other superalloy.


I've seen stainless steel coax for cryogenic applications (very low 
thermal conductivity going in and out of a dewar), but it had a thin 
silver plating.  For microwave frequencies, the plating was thicker than 
skin depth.

I've also seen delay line coax, where the center conductor is a tight 
helix: the inductance/unit length is high so the propagation speed is 
slow (and the Z is high, too). That stuff was quite lossy, although not 
in a "dB/wavelength" sense.