Rick (W-A-one-R-K-T) wrote:

What do you all think of using heavy duty nylon rope instead of wire for
guys?

I have a Rohn 25G up 50 feet with a 2M/220/440 vertical on a 10-foot mast
on top of the tower. It is guyed at 30 feet with standard steel guy wire.
I was just up the top of it two days ago installing the vertical, and it
seems rock solid.

Now my next project is to put up a 3-element tribander, and while my guess
is it'll probably be OK without any additional guying, the paranoid in me
says "hey, bozo... put up another set of guys!".

I'm wondering if heavy duty nylon rope will be sufficient. It'll sure be
easier to work with, and there won't be the issue of having to break up
the guys every so often to keep them from resonating.

There is a ham on the other side of town that has FOUR (4) Rohn 25G's up
120 feet each, arranged in a square, and fed with a phasing network as
phased verticals for 80 meters. Each of the four towers is guyed in two
or three places with polypropylene rope. Been up a long time and seems
OK. But, there isn't a tribander and rotator on top.

The advantage of using rope is that it's nonconductive, which won't distort
the HF yagi's radiation pattern. If you are going to use rope, I recommend
you take a look at the comparison chart listed on McMaster-Carr's website
(http://www.mcmaster.com/). The material and the construction will have
something to do with the amount of stretch, UV resistance, etc. You'll see
that double-braided polyester or nylon would appear to be good choices for
their UV and stretch resistance.

If you don't place the guys immediately under the yagi, metal guys will work
fine if you break up any in-band resonances with insulators. For safety, use
*only* compression insulators (not strain insulators). I used to have a
homebrew 3-el 15m yagi at 38' (26' mast + 12' roof). Originally, I guyed it
w/ #14 solid galvanized steel wire. Eventually, the wire rotted-thru, and
down she came (it was not a good day). After repairing the yagi, I replaced
the guy wire with 1/16" 1x19 strand stainless steel wire rope (500# breaking
strength). That lasted another 15 years until I moved. The wire is still
like new -- no signs of rot. It was a worthwhile investment. Because of
your increased loading, you'd want to use something stronger than what I
used.

Bryan WA7PRC