Antenna Comparisons: DXF vs DXV vs Competitors | Greyline Performance

The Signal Lab

Antenna Comparisons — VDA vs. Everything Else

Not all verticals are built the same. Not all wind ratings mean the same thing. Not all manufacturers publish the same data — or any data. This page is the comparison you do before you buy.

I. The Design Split

Ground-Fed Monopole vs. Vertical Dipole

Every HF vertical falls into one of two camps. The design choice made at the feedpoint determines everything downstream — ground system requirements, noise floor, installation flexibility, and performance on concrete, asphalt, rooftop, or frozen soil.

Ground-Fed Monopole

  • Feeds at current maximum — maximum I²R loss through soil
  • Performance tied to ground conductivity
  • Requires 32–120 buried radials for efficiency
  • Radial field extends 200ft+ on 160M — toward every noise source on the lot
  • Trap-loaded designs add resistive loss at each trap
  • Installation location fixed by ground system

Greyline VDA

  • Elevated feedpoint — return current through lower element, not through soil
  • Performance independent of ground conductivity
  • No radials required — 2" pole footprint
  • Place it in the quietest spot on the property
  • No traps, no coils — no resistive loss path
  • Works on concrete, asphalt, rooftop, frozen ground

II. The Number They Don't Publish

Outer Diameter — Why It Matters More Than Anything Else

Wind load on a pole is calculated from projected area: height × outer diameter. That number determines base bending stress, fatigue loading on every gust cycle, and ultimately whether the pole survives. It is the single most important structural variable in the design.

Greyline publishes outer diameter: 2 inches, full length. It is the smallest OD of any full-HF-coverage antenna available. Every wind rating on this site is derived from that geometry using ASCE 7-10 structural engineering methodology — actual math, published standard, verifiable numbers.

The nearest competing flagpole antenna uses approximately 4" OD — a number their manufacturer declines to publish. It is inferred from their own base insulator dimensions, which they do publish. At the same 24-foot height, that geometry produces roughly double the projected area and double the wind load. They claim a higher unflagged wind rating than Greyline at that height, with no engineering standard cited.

Projected Area at 24 Feet

4 ft²

Greyline · 2" OD

vs.

8 ft²

Others · ~4" OD

Wind force scales with projected area linearly and with velocity squared. A pole with twice the projected area at the same height and moment arm cannot honestly claim a higher wind rating than a pole with half the area — not under any recognized structural engineering standard.

When a manufacturer does not publish outer diameter, that omission is the answer. Ask for it. Ask which engineering standard their wind rating uses. If they can't cite one, you have your answer.

III. Head to Head

VDA vs. Competing Flagpole Designs — 24-Foot Class

Specification Greyline VDA 24' Others — 24 ft Class
Outer Diameter 2" — published ~4" — not published
Projected Area 4 sq ft ~8 sq ft (inferred)
Wall Construction Graduated — 0.125" lower / 0.065" upper Uniform 0.125" full length
Wind Rating 70 MPH — ASCE 7-10 derived 95 MPH — no methodology cited
Engineering Standard ASCE 7-10 — published Not stated
Weight Significantly lighter ~45 lbs
Radial Field Not required Not required
Ships Artisan Production - current lead time at Checkout 24–30 day build time
Transformer Ships with antenna Ships separately — arrives ~10 days after
OD Published Yes No

Others' OD inferred from published base insulator dimensions. Wind methodology not cited by competitor. Greyline wind ratings per ASCE 7-10.

IV. Trap-Loaded Verticals

The Hidden Cost of Resonance

Trap-loaded resonant verticals — the Cushcraft R9, Butternut AV680, and similar designs — achieve multiband operation by inserting traps (parallel LC circuits) at specific points along the radiator. Each trap makes the antenna electrically resonant on a target band by blocking current above that point.

The tradeoff: at each trap frequency, a portion of transmit power dissipates as heat in the trap's resistive components rather than leaving as RF. On lower bands where current passes through multiple trap stages, this loss is cumulative. The antenna also requires a ground radial system to function efficiently, since the feedpoint is at the base.

The Greyline VDA has no traps, no coils, no resonating elements. It is a full-length radiator from feedpoint to tip. An external ATU handles the multiband matching. No resistive loss path between input power and radiation — every watt goes toward the signal.

Physics Standard

All Greyline antenna claims are held to the standard established in Robert Zavrel W7SX, Antenna Physics: An Introduction (ARRL, 2020) and Kraus W8JK, Antennas (McGraw-Hill, 3rd Ed.). If a claim doesn't survive that review, it doesn't appear on this site. Full technical reference →

Have a field experience, a correction, or a pro tip on this topic? We want to hear it. This page is a living document. · 435-200-4902 · Contact →

Ham Radio is fun again! Pass it on... 73, The Greyline Performance Team · Sun Valley, Idaho