Does the DeltaRex need radials?

No. DeltaRex is a closed-loop antenna and does not require a radial system.

Do I need a tuner with the DeltaRex?

Usually not on 40–10 m with an internal ATU, except on 30 m where an external tuner is required. For 60 m and 80 m, an external tuner is always needed.

Where should I place the common-mode choke?

Place a 1:1 current choke ~8 m down the coax (≈0.1λ). Always use at least a 26 m feedline to the shack and a choke before shack entry.

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3.6kW DeltaRex - The Ultimate Low Angle DX Multiband Deltaloop

€377,00 EUR

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The DeltaRex is a solid, base station-class multiband delta loop antenna designed for high-performance DX and NVIS operation from 40 m to 10 m, with usable coverage on 60 m and 80 m NVIS. Built for durability, the DeltaRex uses a heavy-duty triangular loop with a 120° bottom vertex and a dual-wire wide-top conductor on ~5 cm spacers to minimize RF loss and maximize long-term reliability.

The loop legs are constructed from 35 mm diameter, 2 mm wall marine-grade aluminum tubing, while the base and all mechanical fittings use 3 mm RVS316 stainless steel. Every metallic component is marine-grade, ensuring all-weather resilience.

Unlike portable loops, the DeltaRex is built for permanent installation. It is fed at the bottom vertex with an included 4:1 UNUN (rated 2.4 kW or 3.6 kW ICAS). A 1:1 current choke should be placed at ~8 m down the coax line (≈0.1λ of the lowest band). Always use at least a 26 m feedline to the shack and add a second choke before entering the shack.

Specs at a Glance

Frequency coverage	80–6 m (DX focus 40–10 m; NVIS usable on 80/60 m)
Feedpoint impedance	~100–150 Ω (transformed to ~23–30 Ω via included 4:1 UNUN)
Power handling	2.4 kW or 3.6 kW ICAS versions
Polarization	Horizontal
Choke recommendation	1:1 current choke at ~8 m (≈0.1λ). Use minimum 26 m coax to shack + choke before shack entry.
Footprint	~11 m top span, ~22.4 m perimeter
Mechanical	35 mm / 2 mm wall Al tubing; 3 mm RVS316 stainless base/fittings

VSWR Sweep with current choke @8m

DeltaRex SWR sweep across 80–10 m

(Indicative) — measured at the feedpoint with the included 4:1 UNUN and a 1:1 current choke ~8 m down the coax (0.1λ). Expect small shifts with height and surroundings. Use at least 26 m feedline and add a choke before shack entry.

Feed System and Choke Recommendation

Typical loop feed impedance is ~100–150 Ω, transformed by the included 4:1 UNUN to ~23–30 Ω. Place a 1:1 current choke at ~8 m (≈0.1λ). Always use at least a 26 m feedline and add a choke before the shack entry.

Mini-FAQ

Does the DeltaRex need radials? — No, it’s a closed loop.
Do I need a tuner? — Usually not on 40–10 m with an internal ATU, except on 30 m where an external tuner is required. For 60 and 80 m, an external tuner is always needed.
Where should I place the choke? — At ~8 m down the coax line (≈0.1λ). Always use ~26 m coax minimum and a choke at the shack entry.