Moonraker MU-49 49:1 1kW EFHW Unun Transformer

The Moonraker MU-49 is a high-power 49:1 unun matching transformer designed for multi-band end-fed half-wave (EFHW) antennas. Suitable for permanent home stations and portable field installations, it allows an operator to build a multi-band HF antenna by adding a suitable length of antenna wire.

Multi-band EFHW operation

The MU-49 covers 3.5–30 MHz, spanning the main HF amateur bands. Moonraker gives 40 metres of antenna wire as an example for operation across the 80, 40, 20, 15 and 10 metre bands.

Key features

• 49:1 unun impedance matching transformer
• Designed for multi-band end-fed half-wave antennas
• Suitable for home and portable field use
• Wide 3.5–30 MHz operating range
• Maximum stated power handling: 1 kW
• Insertion loss from 0.3 to 1.65 dB, depending on frequency
• SO-239 coaxial connection
• Side-mounted connection studs

Technical specifications

• Model: MU-49
• Transformer type: 49:1 unun
• Frequency coverage: 3.5–30 MHz
• Power handling: Up to 1 kW
• Insertion loss: 0.3–1.65 dB, frequency dependent
• RF connector: SO-239
• Wire connections: Side studs

Build a practical multi-band wire antenna

Connect a suitable antenna wire to the transformer and feed it using 50-ohm coaxial cable terminated with a PL-259 plug. The final wire length and installation should be adjusted for the required bands and checked with a suitable antenna analyser or SWR meter before transmitting.

Please note: The 1 kW figure is the manufacturer's stated maximum power-handling rating. Always use antenna wire, coaxial cable and connectors suitable for the intended RF power and operating conditions.