Wire antenna selection guide

Which wire antenna to build — compared honestly with performance assessments.

The question

"I have trees and wire. What antenna should I build?"

The answer depends on how much space you have, how many bands you want, and how much you are willing to compromise.

Comparison

Antenna Bands (no tuner) Length Supports needed Feedline Complexity
Resonant dipole 1 half wavelength 2 (center + ends) coax + 1:1 balun simple
Fan dipole 3-5 longest half wavelength 2 (center + ends) coax + 1:1 balun moderate (multiple wires)
EFHW (49:1) 4 (40/20/15/10) 66 feet 1 (end feed at ground) coax + 49:1 unun simple
OCF dipole (4:1) 4 (80/40/20/10) 135 feet 2 (off-center + ends) coax + 4:1 balun moderate
G5RV 7 (with tuner) 102 feet 2 (center + ends) ladder line + coax + tuner moderate
Random wire (9:1) all (with tuner) 53-84 feet 1 (end feed) coax + 9:1 unun + tuner simple
Full-wave loop all (with tuner) full wavelength (270 ft for 80m) 4+ coax + 4:1 balun + tuner complex (many supports)

Recommendations by situation

"I have one tall tree and limited space"

Build an EFHW. 66 feet of wire from the tree to a low point. The 49:1 unun at the feed end connects to your radio. No tuner needed on 40m, 20m, 15m, and 10m. The EFHW is the most popular portable antenna because it needs only one support point.

"I have two trees 100+ feet apart"

Build a fan dipole or OCF dipole. Two supports, one feedline, multiple bands without a tuner. The fan dipole gives full performance on each band. The OCF dipole covers four bands from a single wire but requires a 4:1 balun and a choke.

"I have a big yard with four trees"

Build a full-wave 80m loop. 270 feet of wire in a rectangle or square, hung from four supports. Feed with a 4:1 balun and use a tuner. The full-wave loop is the quietest wire antenna (rejects local noise) and works on every band. The all-around best wire antenna if you have the space.

"I have almost no space"

Build a random wire with a 9:1 unun. Any length of wire (avoid multiples of a half wavelength) out a window, along a fence, up a tree, over the roof. The 9:1 unun matches the random impedance to something a tuner can handle. Performance is unpredictable but it radiates, which is more than no antenna does.

"I want maximum performance on one band"

Build a resonant dipole. Cut to the exact length for your target band. Feed with coax and a 1:1 balun. A resonant dipole at a half wavelength above ground is the reference antenna — 0 dBd by definition. Nothing else this simple performs as well on a single band.

The honest truth about wire antennas

Every wire antenna works. Some work better than others. Height matters more than type — a poor antenna design at 60 feet outperforms a perfect antenna design at 20 feet. Get wire in the air as high as possible, and the design details become secondary.