News

November 1, 2021

A Portable Antenna

—Daryl DeVault, KE5SAB

   I’ve been putting together an emergency portable all-band system, and I needed a portable HF dipole antenna. By “portable” I mean:

  • something that doesn’t weigh a lot;

  • something that stands up on its own;

  • something that will break down for transport.

   I decided to use the old Vietnam-era military fiberglass tent poles. They’ve been available for years and I used several of them to build my 30-foot inverted Vee in the back yard. I found more at Omaha’s Military Surplus in Ft Worth—$50 for a bag of 12 poles and 4 bases.

   Each pole is about 44 inches long. I made 3 sets of poles: five poles for the mast to go as high as 18 feet, and two sets of 4 poles to support the antenna legs. These can go up to 14.5 feet. This will make a versatile inverted Vee dipole suitable for uneven ground if needed.

   I painted the poles with bright orange spray enamel and the bases with bright yellow. This does two things. It makes them more visible and less likely for someone to accidentally walk into one of them, and it helps preserve the fiberglass. As the fiberglass ages the original gel coating starts to come off. This leaves raw fiberglass on the surface—and in your hands! Not good!

   I put an eye bolt in the top of each of the top poles. This allows me to use a rope to pull the antenna up into position. I tied the guy ropes to the top pole allowing it to run over the eye bolt thus keeping the guy ropes in position.

   I found that the center pole needs 3 guy lines to keep it stable, but the end poles need only 2 guys as the antenna acts like the third line to keep it steady.

   When I took a short vacation a few weeks ago in Davis, Oklahoma, we stayed in a cabin out in the woods. Randy Morton, KE5EOT, loaned me a G5RV 450-ohm window line antenna. It’s around 90 feet long, but I was able to tie off the ends on some trees and set up the mast in the middle.

   I set up my Yaesu FT-897 in the cabin and ran a 100-foot coax to the antenna. Using around 100 watts I made four contacts in an hour or so: 2 in California, and one each in Utah and Pennsylvania.

   So, this is my kit:

  • FT-897 all-band radio;

  • Portable HF antenna;

  • Portable VHF & UHF antenna;

  • A 1500-watt portable gas generator;

  • A good 12-volt sealed battery;

  • And a small laptop with Winlink capability.

  I plan to upgrade the VHF/UHF antenna, and I’m getting the laptop up to speed. Questions? Just shoot me an email, daryl.ke5sab@gmail.com

73, Daryl