[TowerTalk] hardline bending radius

[Jim Brown]

On 11/17/2012 8:20 AM, K1TTT wrote:
> The 1/2" stuff I have used could be bent pretty tight, I wouldn't go much
> less than 1' radius though without proper tools.

And not all hard line is created equally in this (and many) regard(s).  
Some mechanical constructions are more flexible than others.  My 
guideline is not a hard number, but rather to observe what it seems to 
"want" to do, and not exceed that.  ALL of my heliax is used, pulled off 
of commercial installations, and I can see little bumps and grinds in 
the TDR if I go to 500 MHz with it, but attenuation measurements are 
within spec up to 100 MHz.  Since my maximum frequency of interest is 50 
MHz and I'm only running 1.5kW into cable rated for 20 times that,. I'm 
not losing any sleep over those minor imperfections.

Bending radius and handling is FAR more critical with cables that have 
an Al jacket and center conductor, like CATV hard line.  It's painfully 
easy to put a nasty kink in 1/2-in CATV hard line, and I've got several 
lengths of junk cable to prove it. :)

73, Jim K9YC