Why the RF.Guru VertX Fan Vertical Radiates Smarter Not Just Bigger

At RF.Guru, every design choice we make is grounded in solid electromagnetic principles — and our VertX multiband vertical is no exception. Covering 6 to 20 meters, it might look like a classic fan vertical at first glance. But take a closer look and you'll notice something different: the feedpoint is not at the base, and the wire elements are strategically offset. That small shift plays a big role in performance.

The Feedpoint Shift: 1.1m Above the Ground Radials

In the VertX206, the feedpoint is positioned 1.1 meters above the radial plane. This is not just to keep the feed system dry or convenient — it's a deliberate performance enhancement. By raising the feedpoint above the ground radial system:

• We elevate the current maximum into space where it can radiate more effectively
• We avoid ground-level coupling losses, which are highest near the soil or base of the mast
• We reduce interaction with nearby obstacles, such as garden fences, branches, or walls
• We enable better low-angle radiation, essential for DX

The radials themselves are laid directly on the ground, creating a stable ground reference that works in harmony with the raised feedpoint.

The 20M Inner Radiator: Full-Length, Quarter-Wave

The central radiator of the VertX206 is a full 1/4-wave vertical for 20 meters, starting exactly at the shifted feedpoint. Since this radiator is physically continuous with the mast, the lower 1.1m section functions as mechanical support only. The radiator begins at the insulated feedpoint, meaning the active radiating section starts higher than in most conventional verticals.

This alone improves:

• Current taper, concentrating energy in the part of the antenna that radiates best
• Low-angle efficiency, since the lower current near the ground is eliminated

The Fan Wires: Strategically Raised

What makes the VertX unique among fan verticals is the positioning of its wire elements. The radiators for 17, 15, 12, 10, and 6 meters are not tapped directly at the feedpoint, but rather start about 20 cm higher than the main 20-meter radiator.

Why? Because the current envelope along a vertical radiator is strongest just above the feedpoint. By starting the wire elements at a point that aligns with this high-current zone:

• We maximize coupling between the coaxial feed and the fan wires
• We preserve current symmetry across the element array
• We ensure each band-specific wire benefits from the same elevated launch height

This prevents underfeeding the shorter wires and results in consistent low-angle performance across all bands.

Smarter Geometry = Stronger Signals

The VertX isn’t just a collection of quarter-wave wires and a feedpoint. It’s a carefully calculated system where:

• The feedpoint height is tuned to maximize radiation efficiency
• The main 20m radiator is full-length and center-fed for stability
• The fan elements are staggered to align with the current maxima

This combination delivers low SWR, high efficiency, and consistent DX performance across all supported bands.

The RF.Guru Difference

While other fan verticals follow tradition, we follow physics. Every centimeter of wire, every millimeter of spacing, is designed to put more signal into the sky and less into the dirt.

That's why the VertX doesn't just work on paper — it performs in the real world. And for us, that's the only metric that matters.

And no, we do not use linear loading…

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