Why Clever Antenna Trickery Doesn't Always Pay Off: A Real-World Test
In the world of multiband vertical antennas, it’s common to see designs that use creative methods to force resonance on multiple bands. Techniques like folding back wires, adding loading coils, or creating complex element geometries are often used to “trick” an antenna into offering a low SWR across many amateur bands. A popular example is the fan-style multiband vertical, often called a “multi-element quarter-wave vertical.”
But is a low SWR the only thing that matters?
We set out to answer this question with a real-world test. Two antennas were built:
- Antenna A: A fan quarter-wave vertical using single straight wires for each band, individually tuned without any folding or loading tricks.
- Antenna B: A similar fan quarter-wave vertical, but with clever wire folding, small loading coils, and element tricks to compress length and pack elements neatly.
Both antennas used the same length of coax, the same switch, radio, and power level. SWR was measured across all bands. Antenna B — the “trick” build — showed excellent SWR (<1.5:1 across most bands). Antenna A had slightly higher SWR on some bands (especially 15 m and 17 m, approaching 2.5:1) — still well within the range any internal tuner can handle.
Next, we compared on-air transmission performance using FT8, monitoring signal-to-noise ratio (SNR) reports from distant DX stations.
The results were surprising
- Antenna A (straight elements) consistently produced better SNR at the DX receive sites.
- Antenna B (folds/coils/tricks) delivered noticeably lower SNR, despite its prettier SWR curves.
- On bands where both antennas used straight, un-tricked radiators, their performance was the same.
Why does this happen?
The answer is the difference between radiation efficiency and impedance matching:
- Tricks like tight folding and small loading coils introduce added reactance and can cause localized current cancellations.
- High RF currents — which should span the active length — get distorted or concentrated in less-ideal regions.
- Net result: less RF is radiated, even while the impedance looks “better” to the radio.
In simple terms: a low SWR doesn’t guarantee a strong radiated signal. You can have a “happy” transmitter feeding a “lazy” antenna.
“But what about tuner losses?”
With quality, low-loss coax and reasonable lengths, placing the tuner at the radio is typically fine. The incremental loss to move mismatch from the antenna to the shack is small compared to the dB you lose with inefficient radiators.
For deeper dives, see: Remote Tuners: Stop Putting Them Where You Don’t Need Them and Reflected Power Isn’t Lost Power: Debunking the SWR Myth.
Conclusion
If you have the space and mechanical capability for full-length quarter-wave elements, avoid clever element tricks and live with minor SWR imperfections. You’ll be louder and heard more often — especially in modes like FT8 where every dB of SNR matters.
Sometimes, the simplest solution really is the best one.
Don’t chase perfect SWR numbers alone. Optimize for real-world signal strength. It’s not what the meter says — it’s how far your signal goes.
Mini-FAQ
- Is low SWR the goal? — It’s a goal for the transmitter, not the whole system. Efficiency and pattern matter more on the air.
- Do folds/coils always hurt? — Not always, but tight folds and small coils often degrade current distribution if over-used.
- Will a shack-side tuner add big loss? — With good coax and lengths, added loss is modest and often outweighed by using efficient elements.
- Why did “straight” win? — Cleaner current envelope, fewer cancellations, and better radiation for the same power.
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