EFHW, EFOC, and EFLW Explained: Which End-Fed Antenna Is Right for You?

When you hear terms like EFHW, EFOC, and EFLW, it can feel a bit overwhelming. But don’t worry—we’ll break it down in simple terms so you can choose the right antenna for your radio needs.

EFHW (End-Fed Half-Wave)
This is the classic version. The wire is exactly a half-wavelength long (or multiple half-wavelengths) for your desired band. It offers excellent efficiency on those specific lengths. Some believe it's a multiband antenna, but that's a common misunderstanding: it only performs well on bands where the wire is a full-wave, half-wave, or other resonant multiple.

Pros:

  • Very efficient on its design frequency
  • Good performance on multiple bands only if those bands are resonant (½λ, 1λ, etc.)
  • Easy to hang from a tree or mast

Cons:

  • Not truly multiband—only works well on resonant bands
  • Needs a good match with a 49:1 transformer
  • Transformer losses can be higher due to the high impedance transformation ratio
  • More sensitive to height: high impedance point (voltage node) near the feed makes it prone to mismatch and increased losses if placed too low

Practical Note:
For 160/80m or 80/40m operation, an Inverted L version of the EFHW—like the one we offer—is typically more efficient and delivers a lower radiation angle, which is better suited for DX. It’s also a more realistic solution for most operators who don’t have the space or height for a full horizontal half-wave.

EFOC (End-Fed Off-Center)
This is a more flexible design. The wire isn’t a half-wave, and it’s fed off-center (not in the middle, not at the end). We typically use a 4:1 unun to match the impedance.

Pros:

  • Works on multiple bands without a tuner
  • Great for operators with limited space
  • Less sensitive to exact length than EFHW
  • Lower transformation ratio means fewer transformer losses
  • Performs reasonably well at lower heights

Cons:

  • Needs a tuner on some bands
  • Not ideal for DX unless well elevated

EFLW (End-Fed Long Wire)
This is the most forgiving. The wire is long, often more than a wavelength, and a 9:1 unun is used to bring the impedance closer to something your tuner can work with.

Pros:

  • Very flexible length and layout
  • Works across many bands with a tuner
  • Great for portable or stealth setups
  • Performs decently even when installed at lower height

Cons:

  • Always needs a tuner
  • Can be noisy in urban environments
  • Less efficient than resonant antennas

Which Should You Choose?
If you want plug-and-play efficiency and can cut your wire to the right length, go with an EFHW—but remember, it’s only effective on bands where the wire is a full-wave or half-wave. Also, EFHW antennas benefit from more height to radiate well, especially for DX. Their high feedpoint impedance and current distribution make them more sensitive to placement. For 160m and 80m in particular, an Inverted L EFHW gives better DX performance and is often the more practical solution.

If space is tricky and you don’t mind using a tuner, an EFOC is a great compromise. Despite what some believe, the EFOC can be as efficient or even better in real-world use, thanks to lower transformer losses and more forgiving impedance behavior.

If you want something quick, flexible, and field-ready, the EFLW is your go-to.

Each has its place, and none are "wrong" choices—just different tools for different jobs.

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Written by Joeri Van Dooren, ON6URE – RF, electronics and software engineer, complex platform and antenna designer. Founder of RF.Guru. An expert in active and passive antennas, high-power RF transformers, and custom RF solutions, he has also engineered telecom and broadcast hardware, including set-top boxes, transcoders, and E1/T1 switchboards. His expertise spans high-power RF, embedded systems, digital signal processing, and complex software platforms, driving innovation in both amateur and professional communications industries.