Field Day Is Over. The Myths Are Still Standing.
By the time this edition reaches your inbox, Europe’s September SSB Field Day is behind us. The temporary stations are being packed away, the logs are ready for inspection, and somewhere a club is still debating which antenna really performed best.
That last question deserves more than a photograph of an SWR display. Did the antenna put more energy in the useful direction? Did the station hear better? Did propagation change halfway through the comparison? Or did we simply make the transmitter happier and give the improvement a much more ambitious name?
This September, we look at what Field Day can teach us, what antenna measurements can actually establish, and why an explanation does not become sound engineering just because it arrives in a polished presentation. But first, a moment for the human side of amateur radio.
Saint Maximilian Kolbe, historically associated with the callsign SP3RN, saw publishing and radio as ways to reach people. His story, however, is remembered above all for his decision to take another prisoner’s place at Auschwitz in 1941.
After a weekend devoted to making contacts, it is worth remembering someone whose life gives that word a deeper meaning. Whatever your beliefs, this is a story about communication, service and the person on the other side—not merely the equipment between you.
Read: The Patron Saint of Ham Radio Had a Callsign
An attractive SWR trace tells you about mismatch at the measurement plane. It does not tell you the antenna’s gain, where the lobes point, how deep the rear null is, or how much accepted power becomes radiation rather than heat.
That does not make the analyser useless. It makes its job specific. Before declaring one Field Day antenna the winner, check whether the measurement actually answers the question being asked. A good match and a good antenna are not interchangeable conclusions.
Read: SWR Cannot Validate Gain, F/B or Radiation Efficiency
Field Day is not only about the most distant station in the log. Regional contacts matter too, and near-vertical incidence skywave—NVIS—deserves a place in the planning. An antenna chosen for long-distance, low-angle work is not automatically the best tool for nearby coverage.
But pointing RF upward is only part of the solution. The ionosphere must return the chosen frequency under the conditions at that time, and the signal still has to survive absorption and noise. More high-angle gain cannot force an unsupported frequency to come back down.
An antenna pattern is not a propagation forecast. This article connects the two without pretending they are the same thing.
Read: PERformer NVIS—High-Angle Gain Is Not Ionospheric Return
A few thousand ohms at the end of a half-wave radiator can look wonderfully impressive in an efficiency calculation. The trouble starts when radiation resistance and loss resistance are compared using different current references, or when transformer and return-path losses quietly disappear from the accounting.
High feedpoint impedance is not an efficiency bonus by itself. The complete installation still matters: the transformer, the RF return path, the feedline, the choke and the surrounding environment. No brand of wire gets an exemption from the power balance.
Read: EFHW Efficiency—Why High Feedpoint Resistance Is Not Free Gain
This series started when someone forwarded me an interview with Greg Mihran, KJ6ER. I left it playing while I worked. It did not remain background listening for long. What caught my attention was how often the explanations seemed to cross boundaries that RF engineering requires us to keep separate: matching and efficiency, model predictions and measurements, feedpoint resistance and physical loss.
Watch the interview that prompted the series
That led to a closer examination of Antennas Primer 1: Antenna Fundamentals, July 2026 edition. With these ideas being shared through videos and club presentations, the distinction matters. A beginner should leave a fundamentals presentation with a clearer understanding—not with confident rules that lead to the wrong conclusion when the installation changes.
My objection is not that people build these antennas, enjoy them or make good contacts with them. It is that several explanations and performance inferences do not follow from the evidence being presented. A useful antenna does not automatically make every explanation of it correct.
Nor is this a competition in producing convincing text. A primer written by a person, assisted by AI, or polished by both still has to satisfy the same physical definitions. Fluent explanations cannot replace consistent current references, a complete loss budget, or measurements of the quantity actually being claimed.
The SWR, NVIS and EFHW articles above introduce three of those problems. The following pieces continue the examination, one engineering question at a time. The references concern the July 2026 edition, not an unspecified later revision.
Zero input reactance does not guarantee 50 ohms. A well-matched load can waste power. A non-resonant radiator can work efficiently through a suitably low-loss matching network. This article separates the definitions and follows the measurement plane through the system, so that one reassuring number does not become the answer to four different questions.
Read: Resonance, Match, SWR and Efficiency
A calculated cable length describes part of a feed system—not automatically the currents achieved in the completed array. Mutual coupling, element impedances, matching, switching and feed losses all matter. To establish the claimed directional performance, we need to examine the actual element currents and test the installed pattern, not simply admire the intended one.
Read: PERformer Arrays—Cable Phase Is Not Element-Current Phase
Antenna modelling is enormously useful. That is precisely why its assumptions deserve to be visible. Geometry, ground parameters, excitation, included losses and numerical convergence determine what the result represents. Agreement with an impedance sweep tests impedance behaviour; it does not silently validate every gain and efficiency figure beside the plot.
Read: NEC Antenna Models—What a Plot Predicts and Cannot Prove
Raising a sparse radial system can improve performance. That observation does not make capacitance itself a dissipative resistance, nor establish a universal inverse-height rule for ground loss. Ideal capacitance stores and returns energy; real power is dissipated in lossy materials. The useful question is how the fields and currents couple into those materials.
Read: Capacitance Does Not Burn Watts
N6LF’s comparison is valuable experimental work: four carefully balanced elevated radials produced nearly the same received signal as 64 surface radials in his 40-metre test arrangement. That does not establish a universal efficiency percentage for any two-radial portable installation. The geometry, current balance, soil and measurement method are part of the result—not optional footnotes.
Read: Elevated Radials—What N6LF Measured and What He Did Not
Measure feedpoint resistance, subtract an assumed ideal radiation resistance, and label the remainder “ground loss.” Convenient? Certainly. Generally valid? No. Real geometry and surroundings can change the radiation resistance as well as the losses. A one-port resistance measurement cannot separate those contributions simply because the spreadsheet has two columns.
Read: Feedpoint Resistance—Why “R − 36 Ω” Is Not Ground Loss
Recognition can be deserved. A portable design can be useful, enjoyable and worth sharing. None of that removes the need to substantiate a particular gain, efficiency or pattern claim. Testimonials describe operating experience; awards recognize contributions. Neither replaces a controlled RF comparison. We can appreciate the achievement without confusing the evidence.
Read: POTA PERformer—An Award Is Not an RF Certificate
A firmware region selector is not regulatory approval, and an amateur-radio licence does not extend the permissions of an unrelated licence-exempt service. The actual conditions depend on the country, frequency range, equipment, antenna, radiated power and channel-access requirements.
This is the broader reality behind the mesh discussion: being able to configure a radio is not the same as being permitted to operate that configuration. The article also explains why evidence for a radio module does not automatically cover every finished device built around it.
Read: Licence-Free Does Not Mean Free to Use However You Like
A transmitter’s duty cycle, the occupancy seen by a receiver, and the useful messages delivered by a network are three different measurements. A channel can become congested even when individual transmitters respect their applicable limits. More beacons, forwarding and retries do not necessarily produce more useful communication.
There is also no single blanket “10% rule” covering everything labelled 868 MHz. The relevant sub-band and access conditions matter. Legal access is not a reservation of interference-free airtime.
Read: 868 MHz Mesh Airtime—A Tragedy of the Commons
Subtracting a very weak receive level from a powerful transmit level gives a level difference. It does not define a passive antenna’s “dynamic range,” and it does not by itself establish the carrier isolation a repeater needs.
Carrier leakage, transmitter noise at the receive frequency, receiver blocking and passive intermodulation are different problems with different limits. Repeater coexistence needs separate, properly defined budgets—not one heroic number doing every job.
Read: Repeater Coexistence—Why 180 dB Is Not Antenna Dynamic Range
A market label is not a site specification. Look at the actual coverage pattern, continuous-duty limitations, PIM test conditions, environmental qualification, connector arrangements and mechanical loads. A higher gain figure is not automatically better coverage, and a prestigious badge does not qualify every model for every installation.
Buy against the requirement—and test the complete installed system.
Read: Repeater Antennas—Specify the Site, Not the Market Label
Nothing that can be diagnosed from wire length alone. A centre-fed, full-wave straight dipole presents a very different feeding problem from a full-wave loop. The geometry, feed position and current distribution determine the impedance and radiation pattern; matching and physical losses determine what reaches the useful field.
“Difficult to connect directly to 50-ohm coax” is not the same verdict as “inefficient antenna.” This article explains why the convenient half-wave dipole is not the only respectable use of wire.
Read: Full-Wave Antennas Aren’t Bad—Dipoles, Loops and Feedpoints
Before this year’s Field Day installation becomes next year’s unquestioned club recipe, keep a record of what was actually built and compared: antenna height and layout, radial arrangement, feedline routing, choke position, operating frequency and conditions. When comparing configurations, control what you can and acknowledge what changed.
Use SWR to investigate matching. Use suitable field measurements to investigate radiation performance. Use propagation information to interpret the path. Do not ask one instrument to certify the entire station.
For the video side, visit Mark, K3ZD—Ham Florida Man—and the featured-video collection. Watch the demonstrations, then follow the accompanying RF.Guru articles for the technical context and the limits of what each example establishes.
Watch: Ham Florida Man × RF.Guru—Featured Videos
Thanks for reading, experimenting and asking the questions that make the next installation better. The best souvenir from Field Day is not a perfect SWR screenshot. It is a clearer understanding of why the station worked—and what to investigate next.
Keep building. Keep measuring. Keep the conclusions within reach of the evidence.