End Fed Long Wire Antennas: Energy Efficiency and DX capabilities
End Fed Long Wire Antennas: Energy Efficiency and DX
EFLW51 — Flattop @ 10 m
- 51 m wire works well on 160–30m with manageable radiation patterns.
- On 20m+, excessive length creates fragmented lobes → poor DX focus.
| Band | Height vs λ | Low-Angle (<15°) | DX | NVIS |
|---|---|---|---|---|
| 160m | 0.29 λ | Weak | Poor | Excellent |
| 80m | 0.68 λ | Moderate | Moderate* | Strong |
| 60m | 0.9 λ | Moderate | Good* | Moderate |
| 40m | 1.2 λ | Strong | Excellent | Weak |
| 30m | 1.7 λ | Strong | Moderate | N/A |
| 20m+ | ≥2.4 λ | Compromised | Compromised | N/A |
*Raise to 18 m for better DX on 80/60m.
EFLW37 — Flattop @ 10 m
Low Bands: 160m poor DX but strong NVIS; 80/60m moderate; 40m good DX.
Mid Bands: 30/20m excellent DX.
High Bands: 17–10m efficient but lobe breakup reduces DX focus.
| Band | Height vs λ | Low-Angle | DX | NVIS |
|---|---|---|---|---|
| 160m | 0.22 λ | Weak | Poor | Excellent |
| 80m | 0.46 λ | Weak | Moderate | Strong |
| 60m | 0.65 λ | Moderate | Moderate–Good | Moderate |
| 40m | 0.88 λ | Moderate | Good | Weak |
| 30/20m | 1.2–1.7 λ | Strong | Excellent | N/A |
| 17–10m | ≥2.1 λ | Compromised | Compromised | N/A |
EFLW22 — Flattop @ 10 m
Low Bands: 80m poor DX but strong NVIS; 60/40m moderate.
Mid Bands: 30/20m efficient, good DX.
High Bands: 17–10m efficient with strong DX performance.
| Band | Height vs λ | Low-Angle | DX | NVIS |
|---|---|---|---|---|
| 80m | 0.27 λ | Weak | Poor | Excellent |
| 60m | 0.39 λ | Weak | Moderate | Strong |
| 40m | 0.58 λ | Moderate | Moderate | Moderate |
| 30m | 0.73 λ | Moderate | Good | N/A |
| 20m+ | ≥1.0 λ | Strong | Excellent | N/A |
Mini-FAQ
- Is longer always better? — No. Wires over 2.5λ create chaotic lobes, poor DX focus.
- Which model is best for 160m? — The EFLW51, though DX is limited. Best for NVIS + some DX on 80/60m.
- Which balances DX & NVIS? — The EFLW37 is the most versatile compromise across 160–20m.
- What for pure DX focus? — The EFLW22 offers the cleanest DX patterns from 30–10m.
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