Momobeam Tetra15‑DF 40/20/15/10M Dual‑Feed Yagi Antennas are multiband HF Yagi antennas engineered with an exceptionally compact design while maintaining high‑level performance across all four operating bands. On 40 meters, these antennas utilize a Reflector/Driver configuration with element lengths reduced through end‑loading, a technique originally adopted by W6NL that preserves near full‑size performance while minimizing overall dimensions. On 20 meters, they employ full-size elements arranged as a reflector, driver, and director, providing strong forward gain and clean directional behavior. For both the 15‑meter and 10‑meter bands, the antennas incorporate four active elements configured as a reflector, driver, and two directors, ensuring excellent gain and front‑to‑back ratios across the higher frequency ranges. Their dual‑feed architecture allows contest stations to operate on two bands simultaneously, delivering monoband‑level performance to each operator when paired with appropriate band‑pass filtering.

These antennas include an assembly tool along with spare bolts and aluminum tubing, and they are built on a square‑boom structure that simplifies the installation process. All hardware is packaged in individually labeled bags, and each aluminum element is clearly marked, enabling fast, intuitive assembly. The system requires two separate coaxial feedlines—one dedicated to the 40‑meter band and the other serving the combined 20/15/10‑meter array. A medium‑ to heavy‑duty rotator is recommended for proper operation. Each antenna is supplied with two 3kW RF choke baluns as standard equipment, a notable advantage since many competing manufacturers only offer these components as optional upgrades.

Tetra15-DF Features and Specifications:

• RF Choke Balun: (2) 3kW included

• Bandwidth@ S.W.R. ≤ 1.5:1:

40M - 200kHz

20M – 350kHz

15M – 450kHz

10M – 800kHz

• Longest element: 51.18ft. (1560cm)

• Power Handling: 10kW

• Wind Area: 20.13 sq. ft. (1.87m²)

• Wind Load: (80 MPH): (1364N) 1124.78 ft. lbs.

• Wind Survival*: 100 Mph (160 Km/h)

• Tower Leg/Mast Diameter: 2.0-2.36in. (50/60mm)

• Tower Lift Side: 2.29ft. (70cm) Weight: 242.50lbs. (110kg)

• Feedline Connector: (2) 50-Ohm UHF SO-239 female

• Tubes and Plates: Aluminum alloy 6061T6

• Hardware: stainless steel

• Insulating Clamps: polypropylene, UV resistant