[Towertalk] Coax and Crank-Ups

Mike Gilmer, N2MG n2mg@eham.net
Thu, 08 Aug 2002 16:48:00 -0300


I tried allowing the coax (RG-213) to "pass through" the standoffs on 
my W-67 (15 years ago), with limited success.  I chose to tape the coax 
to the arms for purely technical reasons:

1) My standoffs were U-shaped (the "U" laying horiz, pointing away from 
the tower) with no captive device at the tips of the "U".  I tried to 
come up with a way to enclose the U and capture the coax (loosely of 
course) but never found anything satisfactory.

2) When allowed to pass through, the coax naturally bunched on the 
ground and was subject to all kinds of abuse - lawn mowers, careless 
people walking/tripping, and worse, either knotting up or having leaves 
and twigs getting caught in it (affecting the reliability of the next 
tower extension).

I ended up taping it horizontally along the last several inches of the 
standoff, so that there was just a small droop with the tower fully 
extended.  When the tower was nested, the coax draped down, just barely 
touching or clearing the ground.

Still, I watched it very carefully everytime I cranked the beast up or 
down.

Mike N2MG

K0MYW wrote:

>  Recent comments warning against cinching coax with 
cable ties, etc., lead me to ask advice about a question 
I have with my crank-up tower.
  It's a U.S. Tower model, and I have the U.S. Tower 
standoff arms. But I'm wondering if it's best to allow 
the coax to dangle freely through the standoffs or 
attach the coax at each standoff.
  I know the subject was discussed in the distant past, 
but no answer I've found seems based upon what's best 
for the coax. Most seem based on whether the coax looks 
better draped from each standoff when the tower is 
cranked down, or is neater if the coax is allowed to 
drop freely through the standoffs and coil at the base.
  Looking at the situation from the standpoint of being 
nice to the coax, rather than from the asthetics of the 
tower when it's retracted, what do experienced crankup 
owners think is the best approach?
  If attaching "fragile" low-loss coax to the standoffs 
is the preferred technique, what is the best method of 
attachment to avoid the sorts of compression problems 
that recent postings have warned about?
  Or if allowing the coax to slide through the standoffs 
is the way to go, any suggestions about how to prevent  
abrasion to the coax jackets as they pass through the 
standoff rings when the tower is raised or lowered?