Testing an End Fed Wire Antenna

Previously we covered building an end-fed random wire antenna.

Recently, it had a better test - down on a rented beach house in a more remote area.

The wire was stretched out in an L shape across the… side-yard?

Read on for more…

The outdoor shower plumbing was used for ground (while nobody was using it, of course).

The unun was set up on the balcony, and people were warned not to poke it. (nobody was even outside on the balcony, it was way too cold…)

The shack was set up indoors, and appropriate refreshments were provisioned.

  • Back left: Power supply - Turnigy power meter and LiFePO4 packs (blog post to come about this)
  • Left: ATU - LDG IT-100, and an excessive amount of ferrite split beads just to be sure on the common mode rejection.
  • Centre: Radio - Icom 7100 main body
  • Right: Controls - Icom 7100 head unit with Baofeng T1 sitting in front
  • Right-er: Gin and Tonic - made using Patient Wolf and radiation-mutated grapefruit.

Performance was quite decent this time as there was no geomagnetic storm - got a voice contact with VK2 and some local FT8 on 80m. Heard some SSB contest stations across the band from 40-15m. Got some good DX with FT8 on 30m, surprisingly late in the day. Still not quite sure how it compares to the inverted-V or where the radiation is going exactly, but some of it is getting out.

Annoyingly, there was some severe local QRM on 30m but that band seemed to be getting out the best, even if we couldn’t hear anything…


  • Add more wire and try 160m. Maybe construct two additional pieces for the inverted-V antenna that allow tuning of 80m but can be borrowed to operate this one on 160m.
  • Use an antenna analyzer on it and see what the complex impedance is on various bands. Definitely depends on where and what shape it’s in.
  • Build an extension cable for the tuner interface to allow moving the tuner up to the unun to minimise high-VSWR coax losses. Not having 10m of RG58 operating at higher VSWR is probably the best improvement that can be made here.
  • Find a good bargain on an ATU that will allow pushing 100w PSK into the antenna.
  • Build a better grounding stake.