Near‑Resonant EFOC29 vs Long Wire EFLW22

When it comes to practical HF wire antennas, two popular end‑fed options are the near‑resonant EFOC29 and the non‑resonant EFLW22. Both can make contacts, but if you want higher efficiency, predictable patterns, and fewer boxes in the line, a near‑resonant design like the EFOC29 usually wins.

1. Basic Configuration & Matching

• EFOC29: ~29 m end‑fed wire with a 4:1 unun. Its length places it near half‑wave (or useful multiples) on several HF bands (40/20/15/10 m), so SWR is already close enough that a tuner is often unnecessary or only trims minor residual mismatch.
• EFLW22: ~22 m end‑fed long wire with a 9:1 unun. Impedance varies widely with frequency and installation, so a wide‑range ATU is almost always required to achieve a safe SWR for the rig.

2. Efficiency & Losses

• Near‑resonance helps: The EFOC29 keeps the 4:1 transformer in a friendlier operating window. Lower mismatch means less heating and less stress on cores and coax. Power goes into the antenna instead of into heat.
• Non‑resonant penalty: The EFLW22’s impedance is often far from the 9:1’s “sweet spot.” Expect more loss in the transformer and feedline, especially with longer coax and higher power. At QRO levels you may also meet thermal limits sooner.

3. Tuner Dependency

• EFOC29: Frequently no external tuner required on 40/20/15/10 m. If used, the ATU only performs light touch‑ups. Fewer parts = fewer failure points and faster deployment.
• EFLW22: ATU is mandatory on most bands. Without it, the rig may fold back. Field use becomes slower and more variable due to constant retuning.

4. Pattern Predictability & On‑Air Results

• EFOC29: Being near half‑wave or useful multiples on several bands yields repeatable lobes and better day‑to‑day reliability for both regional and DX paths. Height and layout still matter, but behavior is consistent.
• EFLW22: Electrically short on some bands and electrically long on others, so lobes and nulls move around unpredictably with frequency and installation. It works, but it’s harder to “aim” reliably.

5. Extending Coverage: 160 m with One Wire

The EFOC29 shines from 80 m through 10 m. You can also adapt it for top‑band NVIS by adding a single ~40 m radial at the transformer side to improve return currents on 160 m. This turns the EFOC29 into a truly flexible all‑HF workhorse without redesigning the entire system. (Expect height, ground, and surroundings to shift exact tuning.)

6. Deployment Practicality

• EFOC29: Simple, lightweight, low‑overhead multiband antenna. Ideal for portable and stealth setups where you want quick, repeatable results with minimal gear.
• EFLW22: More boxes and more variability: 9:1 unun, counterpoise/ground, ATU, and more iteration to find a sweet spot. Effective, but with added complexity.

Best practice: Regardless of model, add a 1:1 common‑mode choke at (or just after) the transformer to keep RF off the feedline and stabilize patterns and tuning.

Conclusion

The EFOC29 offers a balanced, efficient, and predictable solution compared to the EFLW22. By leveraging a near‑resonant length and a well‑matched 4:1 unun, it delivers multiband coverage with fewer losses and less fuss. With an optional ~40 m radial for 160 m NVIS, it becomes a serious candidate for full‑HF coverage in a compact, portable‑friendly package.

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