[TowerTalk] Split Loom as an anti-critter device?

[Jeff DePolo]

> There is:
> 
> 1) Smoothwall hardline.
> 
> 2) Spiral corrugated hardline (like FSJ4).
> 
> 3) *ringed* (my term) corrugated hardline (like LDF4).

"Helical" corrugation is the term for the "spiral" type, which is how the
original Heliax was made, and is how it got the name.  

"Annular" corrugation is the technical term for the "ringed" type.

Modern Superflex Heliax type cables (e.g. Commscope FSJ, RFS SCF), and most
air-dielectric corrugated cables (HJ, HCA, et al), use helical corrugation.

Modern non-Superflex, foam-dielectric, corrugated cables like LDF, LCF, et
al have annular corrugation.

As Steve said, Superflex is not a good choice outdoors.  We never, ever, use
Superflex outdoors in commercial work.  Jumpers from the main feedline to
the antenna are made of regular Heliax (typically 1/2"), not Superflex.
Superflex gets used indoors where its flexibility is needed and where
durability and the elements are not a concern.

I can't count how many water-logged Superflex antenna jumpers we've had to
change out over the years, installed by those that didn't know any better.
Lessons learned the hard, expensive way.

Burying regular (non-Superflex) Heliax is fine, and no additional protection
is generally required except in unusual soil conditions (rocky, unstable),
or when it could be subject to crushing forces such as if buried at a
shallow depth below a vehicular pathway.  There are many thousands of miles
of directly-buried Heliax in the ground at AM broadcast facilities around
the world.

				--- Jeff WN3A


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus