Why an EFHW Inverted-L for 160m/80m outperforms a 20m long vertical with a Tuner

Many hams consider using a 20m-long vertical with a tuner for multiple bands, but how does it compare to an End-Fed Half-Wave (EFHW) Inverted-L for 160m/80m? The differences in efficiency, radiation pattern, and matching losses make the EFHW Inverted-L a superior choice for practical operation.

1. Efficiency: Why the EFHW Wins

A 20m vertical is:

  • ¼-wave on 80m → Moderately efficient
  • ⅛-wave on 160m → Extremely inefficient due to high ground losses

On 160m, a 20m vertical is too short, leading to a very low radiation resistance (~1Ω) and high ground losses. While it works fairly well on 80m, using it across bands requires a matching network that introduces losses.

In contrast, an EFHW Inverted-L (such as those from RF.Guru) is:

  • Resonant, requiring no lossy matching networks.
  • Half-wave in length, ensuring higher radiation resistance (~2-5 kΩ).
  • Less ground-dependent, as the current is distributed along the antenna rather than concentrated at the base.

2. Radiation Pattern: The EFHW Offers More Usable Takeoff Angles

A 20m vertical has different radiation characteristics on each band:

  • On 80m, it radiates well for DX but lacks NVIS coverage for local contacts.
  • On 160m, it has very poor efficiency and excessive ground losses.
  • An EFHW Inverted-L, when installed properly, provides:
  • A mix of low-angle radiation for DX and higher-angle radiation for NVIS (on 80m).
  • More consistent performance across both bands.

3. Matching & Losses

  • A 20m vertical requires a tuner, which adds insertion loss.
  • On 160m, the extreme mismatch leads to very poor efficiency in a tuner or matching network.
  • An EFHW Inverted-L uses a simple transformer (49:1 or 64:1), which is far more efficient than a reactive matching network.

4. Practical Considerations

  • A 20m vertical requires a ground radial system for best performance.
  • An EFHW Inverted-L can be installed more flexibly, requiring only one support.

Conclusion

While a 20m vertical works reasonably well on 80m, it performs poorly on 160m due to excessive losses. An EFHW Inverted-L is a better solution because:

  • Higher efficiency, especially on 160m.
  • A more balanced radiation pattern suited for both DX and NVIS.
  • Lower losses by avoiding inefficient matching networks.
  • Easier installation and tuning.

For high-performance multi-band operation, consider:

If you want to work 160m and 80m effectively, a properly installed EFHW Inverted-L is a far better investment than trying to force a 20m vertical to work inefficiently on lower bands.

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.