Faraday Strips: 23% of Nothing Is Still Nothing
It’s true — wide “Faraday Strip” radials are more efficient than plain wire radials and easier to deploy (no tangles, no knots, just roll them out). They also have lower resistance and slightly better capacitive coupling to the soil. But they take up more space, add weight, and the claimed performance numbers sound far more impressive than they really are.
What does “+23–28% relative field strength” actually mean?
Great question — should we really be skeptical about how “useful” that percentage is? Let’s find out.
“Field strength” is an electric-field amplitude (E, in V/m). When a manufacturer says “+23–28% field strength,” that’s an increase in amplitude, not power. To convert that into something meaningful, we use 20·log₁₀:
- +23% amplitude → +1.80 dB
- +28% amplitude → +2.14 dB
If they meant power (as in S-meter or received signal power), we’d instead use 10·log₁₀:
- +23% power → +0.90 dB
- +28% power → +1.07 dB
Since the product description explicitly says “relative field strength,” the fair reading is amplitude — about +1.8 to +2.1 dB, or roughly ⅓ of an S-unit on most radios. If you interpret it as power, it’s half that. Either way, it’s a small change.
Why can wider “strip” radials outperform four thin wires?
Two legitimate reasons:
- Lower RF impedance — wide conductors have less skin-effect resistance at HF.
- Improved capacitive coupling — a wider surface couples better to the earth in the near field, lowering return-path losses.
So yes, four wide strips can beat four thin wires — and a ~2 dB improvement is plausible, especially in close-in field tests over average soil. But that’s still a modest bump, not a game-changer.
…but it still won’t touch a real radial field
For ground-mounted verticals, efficiency is dictated mostly by ground loss. The big win isn’t in making the radials wider — it’s in having more radials.
| Number of on-ground radials | Approx. loss (40 m band) |
|---|---|
| 4 | ~7 dB |
| 8 | ~3.7 dB |
| 16 | ~2.8 dB |
| 32 | ~1.8 dB |
| 60–120 | ~1.0 to 0.1 dB |
Going from four to thirty-two radials can claw back nearly 5 dB on 40 m — that’s an order of magnitude more improvement than the ~2 dB you might get from using four “Faraday Strips.” Classic broadcast and Rudy Severns data agree: quantity beats width every time, with diminishing returns beyond a few dozen radials.
Portable or emergency setups — what actually helps?
- More short wires > fewer wide strips. Carry a roll of lightweight wire and lay down 8–16 radials instead of four heavy straps. With limited radials (≤8), shorter and more numerous is usually better than longer and fewer.
- Elevated tuned radials. If you can lift them 0.05–0.1 λ above ground and tune for resonance, four radials can rival the performance of a dense on-ground field — the best “dB-per-kilogram” solution for portable ops.
Bottom line
- The +23–28% “field strength” claim equates to roughly +1.8 to +2.1 dB — about a third of an S-unit. It’s real, but small.
- Four on-ground radials are inherently lossy; making them wider helps a little, but adding more radials (or using elevated ones) helps a lot more.
- If portability matters, focus on smart radial strategy, not marketing math.
As Rudy Severns (N6LF) demonstrated in his decades of field measurements, efficiency improves fastest when adding more radials, not when making them wider or shorter. The physics hasn’t changed — only the marketing has.
Mini-FAQ
- Q: Does strip width ever hurt performance? — A: Only if it changes tuning dramatically; otherwise, no. Wider conductors mainly lower resistance.
- Q: Is +2 dB audible? — A: Barely. It’s measurable in lab gear but often masked by fading or band noise.
- Q: Should I buy them for field use? — A: If convenience matters more than weight or price, sure — but don’t expect miracles.
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