Radials Have Two Jobs — Most Vertical Myths Start by Confusing Them

(And what “without radials” really means in the real world.)

A lot of vertical antenna confusion starts with one innocent word:

Ground.

Hams use “ground” to mean at least four different things:

• DC safety ground
• RF return path
• Counterpoise
• Electromagnetic ground plane or mirror

Those are not the same thing.

So when someone says, “My vertical has a ground,” the first question should be:

What kind of ground?

Because a copper rod in the dirt, a few wires on rocks, four tuned elevated radials, a mesh sheet, a tripod, a coax shield, and seawater are all very different things at HF.

The antenna does not care what we call it.

It only cares about:

• Where does the RF current flow?
• How much power is lost as heat?
• What fields are forced into lossy earth?
• What part of the structure is actually radiating?

That is where radials come in.

Radials have two jobs.

First Job: The Electrical Job

Radials provide the RF return system.

A vertical monopole is not a complete antenna by itself.

The vertical element is one side of the antenna. The other side has to be something:

• radials,
• a counterpoise,
• an elevated ground plane,
• a conductive surface,
• the coax shield,
• the mast,
• the operator,
• the soil,
• or some random combination of all of them.

The RF current will return somehow.

The only question is whether it returns through a low-loss, intentional structure, or through whatever accident happens to be nearby.

This is the first job of radials:

Radials give the feedpoint current somewhere low-loss and predictable to go.

That sounds simple, but this is already where many myths begin.

A radial system is not “some metal near the base.” A radial system is a controlled RF return structure. It must have enough conductor, in the right geometry, with low enough resistance, over the part of the field where the antenna actually needs it.

A small conductive blanket under the feedpoint is not automatically doing that. A few short wires are not automatically doing that. A tripod on a rock is not automatically doing that.

The RF current distribution decides. Not the product name.

Second Job: The Electromagnetic Job

Radials reduce field penetration into lossy earth.

The second job is less intuitive, but just as important.

A vertical over perfect ground behaves as if there is a mirror image of the antenna below the surface. That is the classic “image antenna” model.

But real ground is not a perfect mirror.

Real ground is dirt, rock, peat, sand, snow, roots, water, minerals, salt, and loss.

If the near electric field from the vertical is forced into lossy ground, transmitter power is dissipated as heat. You may still get a beautiful SWR dip. You may still make contacts. But some of your QRP power is warming the planet instead of leaving the antenna.

This is the second job of radials:

Radials form an electromagnetic screen that reduces field penetration into lossy ground.

That is the “mirror” part.

But be careful: the mirror is not magic. It is not created by wishful thinking, conductivity labels, or a little square of RF fabric. A good RF mirror requires enough low-loss conductor over enough area.

A dense radial field starts to behave like a conducting surface because the spacing between conductors becomes small enough that the field “sees” a screen instead of mostly seeing dirt.

That is why more radials help.

Not because each radial is magical.
Not because each radial must be resonant.
Not because copper has spiritual properties.

More conductors reduce the amount of RF field and return current forced through lossy soil.

The Two Jobs Are Connected

Strictly speaking, the electrical and electromagnetic jobs are not separate physics. They are two views of the same Maxwell problem.

But for human brains, the separation helps.

Electrical View

The radial system carries the return current and stabilizes the feedpoint.

A poor radial system often causes:

• higher loss resistance,
• more common-mode current on the coax shield,
• less predictable impedance,
• more RFI risk,
• more “why does SWR change when I move the coax?” behavior.

A good radial system usually gives:

• lower loss resistance,
• more predictable feedpoint behavior,
• less current on the coax shield,
• more transmitter power converted into radiation.

Electromagnetic View

The radial system controls the fields near the base of the antenna.

A poor radial system allows:

• more near-field energy in lossy earth,
• worse ground loss,
• a fake sense of success from SWR alone.

A good radial system creates:

• less field in lossy ground,
• a better effective RF mirror,
• stronger useful radiation from the same applied power.

Same system. Two ways of looking at it.

Why “Capacitive Ground Loss” Confuses People

A common question is:

“If the loss is capacitive coupling into the ground, why do radials help?”

Because the problem is not capacitance by itself.

The problem is where the displacement current goes after the field couples.

A vertical produces electric fields. Those fields terminate on the surrounding return structure. If the return structure is mostly lossy earth, current flows in lossy earth. That creates heat.

Heat is not DX.

Radials intercept part of that field and provide a much lower-loss conducting path back toward the feedpoint.

So yes, the coupling has a capacitive or displacement-current component. But the loss happens because the return path includes resistance.

That is why low-resistance conductors, spread over the correct region, reduce loss.

SWR Is Not Efficiency

This needs to be repeated until it becomes boring:

A low SWR does not mean the vertical is efficient.

A dummy load has a great SWR.

A vertical with a lossy ground system can also have a nice SWR because loss resistance conveniently helps make the feedpoint look closer to 50 ohms.

That is not success. That is camouflage.

The real question is:

How much of the applied power is radiated, and how much is lost in soil, fabric, coax shield, hardware, and nearby objects?

A poor radial system can make tuning easier while making the signal weaker.

That is why field strength, controlled A/B tests, current measurements, and realistic loss thinking matter more than “my tuner liked it.”

The Short-Radial Myth

The myth goes like this:

“Rudy Severns showed that short radials work just as well.”

No.

That is not the lesson.

The correct lesson is more like this:

Many short radials can be useful. A few short radials are not the same thing.

That distinction matters.

A large number of short radials can create a dense screen near the feedpoint. That may reduce ground loss very effectively for the amount of wire used. But if you reduce both length and number, the system collapses into a sparse, lossy compromise.

Four short wires are not a radial field.

Eight short wires are not a magic mirror.

A handful of wires may be enough to get a match. It may even be enough to make contacts. But it is not the same as a serious ground system.

Short radials can approach good performance only when used in large numbers. The mistake is turning that into “a few short radials are fine.”

The Faraday Cloth Myth

Now let’s apply the two-job model to Faraday cloth.

A conductive cloth laid under a vertical seems attractive:

• no tangled wires,
• fast deployment,
• easy to weight down,
• compact,
• visually similar to a “ground plane.”

But the antenna does not care how attractive it looks.

It asks two questions:

• Can this cloth carry the required RF return current with low loss?
• Is it large enough to control the fields over the important region?

For many small cloth patches, the honest answer is:

Not really.

The cloth is too small to act like a radial field, and often too resistive to behave like copper wire.

A 1.5 m × 1.5 m cloth under a vertical on 40 meters is not a ground plane. It is a small conductive patch.

Better than nothing? Often yes.

Equivalent to a real radial field? No.

A cloth rectangle can help stabilize a portable antenna. It can reduce some feedline current. It can be mechanically convenient on rocks or snow. But it should not be sold, believed, or modeled as if it were thirty-two copper radials.

Faraday Strips: Better Geometry, Still Not Magic

Cutting conductive cloth into strips is a better idea than using one little blanket.

Why?

Because now the material begins to behave more like radials.

A wide strip can have:

• lower RF impedance than a very thin conductor,
• slightly better capacitive coupling to the nearby ground,
• easier deployment than loose wires.

So yes, strips can beat thin wires in some narrow comparisons.

But this is where marketing math often enters.

A claim like “+23 to +28% relative field strength” sounds huge. In field-strength terms, that is roughly +1.8 to +2.1 dB. Real, measurable, but not revolutionary.

Wider strips can help, but the improvement is modest, and four wide strips still do not compete with a real radial field.

The big improvement is usually not width.

The big improvement is:

More radial coverage.

Four wide strips may beat four thin wires.

But sixteen or thirty-two ordinary wires will usually beat four fancy strips.

Quantity and geometry win. Marketing loses.

Ground Radials and Elevated Radials Are Different Systems

Another source of confusion is the question:

“How many radials do I need?”

The answer depends on whether they are on the ground or elevated.

On-Ground Radials

On-ground radials are normally not tuned resonant elements.

They are part of a lossy-ground mitigation system.

They are forgiving. They can be messy. They can be slightly different lengths. They can lie on grass, soil, rocks, or snow. They do not need to be perfect.

But they need coverage.

For on-ground systems, many radials are usually better than a few. A dense field reduces ground loss because less return current is forced through lossy soil.

Elevated Radials

Elevated radials are different.

They behave much more like antenna elements. They must be treated as part of the antenna, not as casual “ground wires.”

They are sensitive to:

• length,
• height,
• symmetry,
• nearby metal,
• feedline routing,
• common-mode choking.

A few tuned elevated radials can work extremely well because the return current is mostly confined to low-loss conductors instead of the earth. But they are less forgiving.

There are also two separate effects that are often mixed together:

• Elevated radials can reduce near-field ground loss.
• Raising the whole feedpoint and radiator can also change the elevation pattern and improve DX-useful angles.

Those are related, but they are not the same lever.

A ground-mounted vertical with radials slightly lifted is not the same as a roof-mounted vertical with the whole radiating system higher above ground.

One mainly changes loss. The other may also change pattern.

The Feedline Is Always Waiting to Become a Radial

When the radial system is poor, the coax shield volunteers.

Not politely. Not predictably. But it volunteers.

If the feedpoint does not see a good return system, the outside of the coax shield becomes part of the antenna. Then you get:

• SWR changing with coax length,
• pattern distortion,
• RFI in the radio or accessories,
• mystery gain in one direction,
• comparisons that are not comparing what people think they are comparing.

This is why a feedpoint choke matters.

A choke does not fix a bad radial system. But it helps prevent the feedline from hiding the problem.

Without a choke, many radial experiments are really comparisons between:

antenna + radial system + coax shield + operator + nearby objects

That is not science. That is a campsite accident with a VNA attached.

So What Should a SOTA or POTA Operator Do?

For portable operation, the perfect radial system is often impossible.

On a windy summit, you may have:

• rocks,
• snow,
• a small operating area,
• no soil stakes,
• no clean way to elevate radials,
• no appetite for a 120-radial broadcast field.

Fine.

Portable radio is always compromise.

But not all compromises are equal.

Elevated Tuned Radials, If the Setup Allows It

For monoband use, a few elevated tuned radials can be very efficient. But they need height, symmetry, and tuning. On a rocky, windy summit, that may or may not be practical.

More Ordinary Wire Radials on the Ground

For multiband portable verticals, this is often the best compromise.

Eight to sixteen lightweight wires are usually more useful than a small cloth rectangle. More wires improve radial density and reduce the chance that the coax shield becomes the missing half of the antenna.

Longer Radials, Once You Already Have Enough of Them

Length helps, but only when the radial system is not too sparse.

A few very long radials can leave large gaps. Many shorter radials may create a better screen close to the feedpoint, where it matters most.

Conductive Cloth or Strips Only When the Mechanics Justify It

Cloth may be useful when it solves a deployment problem:

• snow,
• rocks,
• no anchoring points,
• high wind,
• very small summit,
• tripod-mounted portable verticals.

But electrically, do not expect a little rectangle of fabric to replace a real radial system.

If using conductive fabric, strips are usually more honest than a blanket. They at least behave more like wide radials.

The Uncomfortable Answer

If someone asks:

“Should I add a rectangular Faraday cloth to my existing six radials, or add six more radials?”

The RF answer is usually:

Add the six more radials.

Especially if the cloth is small.

A cloth patch may make deployment neater. It may make the antenna tune differently. It may reduce some common-mode current. It may be better than bare rock.

But six additional radial wires increase the actual radial field.

That usually matters more.

If the operator already has twelve, sixteen, or more radials and wants a small cloth under the feedpoint for mechanical convenience, fine. But do not confuse convenience with a miracle.

A rectangle of cloth under the tripod is not the same thing as a low-loss radial field extending over the region where the antenna’s return currents want to flow.

The Key Mental Model

Stop thinking of radials as “ground.”

Think of them as the lower part of the antenna system.

They do two jobs:

• Electrical: they provide a low-loss RF return path so the current does not have to return through soil, coax, mast, operator, or random nearby metal.
• Electromagnetic: they form a screen that reduces field penetration into lossy earth and makes the antenna behave more like it is working over a conducting plane.

Those two jobs are connected, but separating them helps explain almost every radial myth:

• A small Faraday cloth fails because it is too small and often too resistive.
• A few short radials fail because the screen is too sparse.
• Many short radials can work because density matters.
• Wide strips can help, but width is not a substitute for coverage.
• Elevated radials can work very well because they change the return-current mechanism.
• A good SWR proves almost nothing about efficiency.
• A poor radial system often turns the coax into the missing radial.

The antenna does not care about slogans.

It cares about current, fields, resistance, geometry, and loss.

That is the whole radial story.

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