The Diamond W721 is a professional-grade, high-performance dual-band wire dipole antenna engineered custom-tailored to provide outstanding long-range HF communication efficiency across the 7 MHz (40-meter) and 21 MHz (15-meter) amateur radio bands. Built by Diamond Antenna, a global leader in high-tier commercial and amateur base station systems, this premium trap dipole is an exceptional choice for municipal emergency backup networks, maritime baseline monitoring, and dedicated high-frequency DX operations. Its pre-tuned inline trap design allows operators to utilize a single physical antenna structure for dual-band operations without requiring complicated, space-consuming parallel wire arrays.
Constructed from heavy-duty, multi-strand copper wire and reinforced with weather-sealed inline trap components, the W721 is engineered to withstand extreme environmental stress, including high wind loads, intense solar radiation, and freezing rain. Measuring a total length of 12.4 meters, it provides a compact physical footprint for a 40m-capable antenna, making it highly suitable for installations in restricted suburban yards, building rooftops, or remote field environments. The antenna functions as a full-sized dipole on 15 meters and leverages highly optimized matching traps to resonate efficiently on the 40-meter band, maintaining a low Standing-Wave Ratio (SWR) across its specified frequencies while presenting a nominal 50-Ohm load to your transceiver.
Central to the W721’s design is its ruggedized center feedpoint balun, which features a heavy-duty, chassis-mounted SO-239 (UHF Female) connector. This interface ensures low insertion loss, excellent power handling, and a secure mechanical link with standard PL-259 terminated coaxial transmission lines. Designed as a long-wire thread installation, the antenna can be deployed easily in a standard horizontal configuration or suspended as an Inverted-V depending on available support structures. Weighing 1.2 kg and shipped complete with robust insulators and durable strain-relief mounting hardware, this premium wire dipole provides a plug-and-play base station solution built for absolute long-term reliability.
Key Features
- Dual-Band HF Resonator: Precision engineered to operate efficiently across the 7 MHz (40m) and 21 MHz (15m) amateur radio bands.
- High-Efficiency Inline Traps: Employs factory-sealed, low-loss matching traps to enable dual-band resonance on a single, compact wire line.
- Durable Weatherproof Build: Fabricated from premium multi-strand wire and heavy-duty insulators to endure severe outdoor climates and high tension.
- Compact 12.4m Length: Reduced structural footprint simplifies deployment in small gardens, urban roofs, or temporary emergency base sites.
- Heavy-Duty SO-239 Interface: Center balun is outfitted with a high-grade UHF Female coaxial socket for secure inline power transmission.
- Flexible Thread Installation: Long-thread wire configuration supports traditional horizontal tensioning or space-saving Inverted-V layouts.
Technical Specifications
| Parameter | Specification |
|---|---|
| Brand | Diamond Antenna |
| Model Designation | W721 |
| Product Type | Dual-Band HF Trap Wire Dipole Antenna |
| Operating Frequencies | 7 MHz (40 Meters) / 21 MHz (15 Meters) |
| Nominal Impedance | 50 Ohms |
| Coaxial Connector Interface | 1x SO-239 (UHF Female, integrated into center balun) |
| Antenna Type Configuration | Long thread wire dipole with matching traps |
| Total Structural Length | 12.4 meters |
| Net Equipment Weight | 1.2 kg |
Package Content
- 1x Diamond W721 Pre-Assembled Trap Wire Dipole Assembly
- 1x High-Isolation Center Balun with SO-239 Port
- 2x Heavy-Duty End Insulators
- 1x User Reference Mounting Guide
