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Tower is up and pre-stretched multi-strand 14 Ga wires are cut & terminated for a multiband fan-style dipole antenna system. Location is the desert southwest of the USA.

Stringing up parts of it are going to be a challenge due to topography, and it will require lengthy tie-down cord on the end of the 75/80 Meter portions. Monofilament would definitely stretch and break down in the sun.

So I'm intending to use paracord and have a quantity of Mil Spec 7 Stranded Type III Nylon black paracord on hand.

My question:

1) Will paracord hold up well enough in the hot sun? And does the color matter? i.e., will black paracord degrade noticeably faster than white?

2) Is there a better alternative?

FYI, I used the same antenna wire mentioned here:

HF SWL antenna wire? Will plain 16-Gauge copper wire work well enough?

SDsolar
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2 Answers2

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Paracord is a usurped and abused term for a wide variety of cords. The US Military previously specified 6 different types of paracord. It is also known as parachute or 550 cord. Originally constructed of nylon to allow shock absorbance in parachutes there are now many made of polyester and other materials.

When considering its use for supporting an outside dipole there are three things to keep in mind: UV resistance, stretch and working strength.

A UV resistant material should be used for outdoor applications or the material will turn brittle and ultimately yield. Nylon, for example, deteriorates under long term exposure to the sun (UV). Check the supplier's specification and pick a UV resistant version. Color itself will not be a factor in UV susceptibility if the cord is already UV rated although some colors may fade under long term exposure to the sun.

Paracord was originally designed to stretch. This may be helpful in providing some wind survivability for the dipole if stretched between trees, for example, but too much stretch may make it difficult to properly tension the dipole.

A dipole with a balun and coax cable can require considerable tension in order to attain the desired catenary droop. You can use on-line calculators to determine the minimum working load for the paracord or simply use a pull scale (fishing, luggage, etc.) on your installation to measure the applied tension to ensure you are operating below the working load of your paracord.

If your supporting cord will rub against trees or other supports, you should take measures to guard against abrasion or choose an abrasion resistant construction.

If you are not committed to using paracord, there are several cords suitable for antenna applications. Mastrant by DX Engineering or Amazon is one such example.

SDsolar
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Glenn W9IQ
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It does work well although weather will eventually get to it. I got at least 10 years out of some salvaged from an old chute probably made in the 50s. Used to support a dipole made of #3 wire (some old 100 A drop line), both for the centre uphaul (always use a loop so you can pull it down when, not if, the feedline connections break) and for the ends tied to trees. When it broke, replaced with UV stable black rope sold for this purpose. I got mine from Davis RF.

A related tip: soldered joints on wire that needs to flex is a bad idea. One thing that works well are Marrettes - the electrical wiring twist-on connectors.

Mike Waters
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George VE3YV
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