Build a Broadband Hexbeam

A hexbeam is a light, compact 2-element beam — a driven element and a reflector bent onto six fiberglass spreaders in a hexagon about 22 ft across. The broadband version is the same proven design sold by the well-known commercial hexbeams, so building it yourself gets you that same antenna for the cost of wire and fiberglass. See the KIO Hexbeam site for more info.

GainDriverReflectorFeedpoint
Top view. The driven element (warm) is the "W" across the top, fed at the centre; the reflector (blue) is the "U" across the bottom. Point the "Gain" direction at the DX. All six bands stack along the same six spreaders (~22 ft / 6.7 m across); feed the centre with 50 Ω coax through a 1:1 current balun (see the Baluns page).

What you get

What you'll need

Putting it together

  1. Bolt the six spreaders to the centre plate, evenly at 60°, sloping slightly upward.
  2. Run the support cord from the centre-post top to each spreader tip and tension it so the tips rise into the classic dome — that 3-D shape is what makes a hexbeam work.
  3. Cut the wires from the table below: per band, two driver legs and one reflector. Pick the bare OR the PVC column to match your wire — don't mix them.
  4. Mark each spreader (or the perimeter cord) with every band's attach point, the lowest band (20 m) outermost.
  5. String the driven elements: each band's two legs run from the centre feedpoint out toward the front and bend at the spreaders — that's the "M."
  6. String the reflectors behind them (the "U"), holding the driver-to-reflector tip gap from the table at the two sides.
  7. Bond all the driver legs together at the centre feedpoint and feed it with 50 Ω coax through a 1:1 current balun.
  8. Hoist it and check SWR on each band. The broadband design is usually right on; if a band sits high or low, nudge that band's driver-leg length (longer = lower in frequency).

Wire lengths, per band

Cut two driver legs and one reflector per band. The tip gap is the spacing held between the driver and reflector tips at the two sides. These are the published broadband-hexbeam dimensions; trim a little for your exact wire and lowest SWR.

Bare copper wire (#14 / #16)

BandDriver leg — cut 2Reflector — cut 1Driver↔reflector tip gap
20m218" / 554 cm412" / 1046 cm24" / 61.0 cm
17m169.5" / 431 cm321" / 815 cm18.5" / 47.0 cm
15m144.5" / 367 cm274.4" / 697 cm16" / 40.6 cm
12m121.7" / 309 cm232" / 589 cm13.5" / 34.3 cm
10m106.8" / 271 cm204.4" / 519 cm12" / 30.5 cm
6m58.5" / 149 cm112.5" / 286 cm6.5" / 16.5 cm

PVC-insulated wire (#14 / #16)

BandDriver leg — cut 2Reflector — cut 1Driver↔reflector tip gap
20m213.5" / 542 cm403" / 1024 cm24" / 61.0 cm
17m165.5" / 420 cm313.5" / 796 cm18.5" / 47.0 cm
15m141" / 358 cm268" / 681 cm16" / 40.6 cm
12m118.75" / 302 cm226.25" / 575 cm13.5" / 34.3 cm
10m104" / 264 cm199.25" / 506 cm12" / 30.5 cm
6m57.3" / 146 cm110.25" / 280 cm6.5" / 16.5 cm

Insulated wire comes out a touch shorter than bare because the insulation slows the wave — that's why the two tables differ. Match the table to the wire you actually use.

Spreader layout — marking in one pass

Approximate radial distances from the centre post outward along a spreader, so you can mark all six bands at once (lowest band outermost). These are scaled from the published ~130″ 20 m spreader-tip radius using the wire-length ratios — a layout aid, not exact build marks. The real geometry settles itself when you string the cut wires, so treat these as where to place each band's element clip and confirm against your wire lengths.

BandDriven wire — radiusReflector wire — radius
20m106" / 269 cm130" / 330 cm
17m83" / 210 cm101" / 257 cm
15m71" / 179 cm87" / 220 cm
12m60" / 152 cm73" / 186 cm
10m52" / 133 cm64" / 164 cm
6m29" / 74 cm35" / 90 cm

The reflector is the outer wire; the driven element sits about one "tip gap" inboard of it. Bands scale together, so if your 20 m radius differs from 130″, scale every row by the same factor.

Feeding & tuning