[TowerTalk] Strange coax failure

[K7LXC--- via TowerTalk]

>  I saw some coax a few years ago where the center conductor  was not 
entirely in the middle of the insulator.  Bad molding?  It  was RIGHT up 
near the shield in some spots and centered in others...   If I remember 
correctly it was a foam  dielectric...

A big problem with foam dielectric  is that it'll cold flow under the right 
conditions. It's a problem with wound  coax baluns. 
 
Cheers,
Steve   K7LXC
TOWER TECH