Measurement-Avoiditis

Measurement-Avoiditis

A Follow-Up to SWR Derangement Syndrome

In last year’s episode of SWR Derangement Syndrome, we met the ham who refused to transmit at 1.2:1 and began “precision dipole surgery” with a flashlight and a nail clipper.

Today we visit the sister condition. The quieter one. The one that doesn’t scream at the SWR meter…
…it simply never measures anything that could ruin the vibe.

Welcome to: Measurement-Avoiditis — the chronic belief that if you don’t measure it, it must be perfect.

Case File: MA-01

“The Choke That Works In All Situations, Everywhere, Forever (Trust Me)”

The patient presents with:

• a freshly wound “universal choke”
• a confident grin
• and exactly zero data, plots, or measurements beyond “it’s a choke, so it chokes.”

When asked, “What’s the common-mode impedance across bands under real feedpoint conditions?”

They respond with the ancient incantation:

“It’s on YouTube.”

The Modern Ham Measurement Toolkit

Standard Lab Equipment (2026 edition)

1. Tape measure (primary instrument)
2. Cheap multimeter (for continuity and emotional support)
3. SWR meter (usually not a real one, but it’s got a needle, so it counts)
4. Bonus item: A VNA purchased for “later” (later never comes)

This set is known in clinical circles as the Triad of Comfort: Length. Continuity. Needle. Everything else is “overthinking” or “elitism” or “engineering.”

Symptom Cluster A: “Resistive Reality Syndrome”

A key diagnostic feature of Measurement-Avoiditis is the obsession with measuring only resistive conditions and calling it “real world.”

Example:

The patient proudly tests their choke on a perfectly polite 50 Ω setup and announces:

“It’s 10kΩ on all bands!”

In other words: they measured it in the spiritual realm, where antennas are always 50 Ω, feedpoints are always well-behaved, and common-mode currents politely ask permission before appearing.

Then they connect it to a multiband antenna whose feedpoint impedance is doing interpretive dance somewhere between “not 50 Ω” and “don’t ask,” and conclude:

“Still 10kΩ. Because I said so.”

Symptom Cluster B: The EFHW Holy Grail Delusion

No follow-up would be complete without the sacred relic:

The “Holy Grail EFHW”

Constructed from:

• Mix 52 (because a forum said it’s “the best”)
• a transformer ratio chosen via vibes
• and a claim that it covers “80 through 10” with “great performance”

Reality, however, behaves like this:

• 80 m: Technically present. Spiritually distant.
• 40 m: Kind of okay, if you squint and lower your expectations.
• 20 m: Fine-ish.
• 10 m: A parasitic carnival ride with bonus lobes and deep nulls aimed at your dream DX.

But the patient is calm, because the only measurement they trust is a glorified SWR reading — which, as everyone knows, is the official international standard for:

• efficiency
• pattern
• feedline current
• transformer loss
• ferrite heating
• common-mode control
• world peace

If the SWR looks friendly, the antenna must be excellent. It’s science.

“My Choke Chokes Fine” — The Most Dangerous Sentence in HF

Measurement-Avoiditis sufferers commonly make blanket statements like:

“This choke works everywhere.”

This is the RF equivalent of saying:

“My brakes work on all roads, in all weather, at all speeds, even underwater.”

A choke that “works” at one band, one power level, one installation, and one feedline length can become a decorative bracelet at another band when the system impedance shifts and the common-mode path changes.

But again: if you never measure common-mode, you’re never wrong.

Symptom Cluster C: The Common-Mode Blind Spot

The patient has strong opinions about common-mode.

They can:

• argue about it for 45 minutes
• recommend ferrite part numbers by horoscope
• declare “you need a current balun” like it’s a moral requirement

But they will not:

• measure feedline current
• measure choke performance in situ
• validate anything beyond “SWR didn’t explode”

In advanced cases, the patient believes common-mode is a fixed number, like a speed limit:

“I have 10kΩ of choking.”

10kΩ where?
On what band?
At what impedance?
With what parasitics?
Under what mounting?
With what power?
With what feedline?
With what cosmic alignment?

They stare, offended, and whisper:

“Don’t bring math into this.”

Field Observation: The Parasitics Nobody Invited

10 meters is where Measurement-Avoiditis gets exposed in sunlight.

At 10 m, everything becomes an antenna:

• the transformer box
• the leads
• the connector
• the ferrite stack
• the windings
• the feedline
• the zip ties
• the hopes and dreams

But because the only test performed is a resistive-ish SWR-ish check, the patient concludes:

“It’s broadband!”

Yes. Broadband in the sense that it’s broadly chaotic.

Diagnosis

To confirm Measurement-Avoiditis, present the patient with the following:

• a simple request: “Can you show a plot?”
• or: “Did you measure common-mode current?”

If they:

• change the subject to coax brands
• say “my buddy said it’s fine”
• accuse you of “overcomplicating ham radio”
• post a screenshot of SWR as proof of radiation

…diagnosis confirmed.

The Cure

(Gentle, because the patient is fragile)

Step 1: Measure something real.

Not just SWR. Not just continuity. Not just wire length. Measure:

• feedpoint impedance across bands
• choke performance under non-50Ω conditions
• common-mode current on the feedline (even a simple clamp + method can teach a lot)

Step 2: Accept a terrifying truth:

An antenna can have a great SWR and still be a mediocre radiator.
The SWR meter is not an RF truth oracle. It’s a transmitter comfort meter.

Step 3: Make a QSO anyway.

Log it. Notice nobody says:

“Congrats, OM, but what was your choke impedance at 18.1 MHz with 3.7kΩ feedpoint reactance and a wet gutter nearby?”

Final Prescription

Measurement doesn’t kill homebrew.
It kills mythology.

And if your design survives measurement?
Congrats — you didn’t just build a thing.
You built a known thing.

Which, in a hobby full of legends, is borderline rebellious.

73
Cynic Corner Clinic — now accepting walk-ins. Please bring your tape measure, multimeter, and… one (1) additional instrument you’re afraid of.

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