Introduction

Understanding MF/HF-SSB radios may seem complex, but a basic grasp is essential for effective maritime communication. This article offers fundamental insights to help you communicate over long distances, though it doesn’t cover every scenario.

 

MF/HF-SSB

FEATURES

Marine VHF Radios

  • Operate within the 150-160 MHz range for short-distance communication.
  • Used for local communication, typically up to 30-50 nautical miles.

HF Radios

  • Utilize frequencies from 1.6 to 30 MHz for long-distance communication.

  • Capable of global communication, especially under favorable solar and atmospheric conditions.

Propagation Types

  • Ground Waves: Effective for short distances (100-200 nautical miles) during the day, extending at night.

  • Sky Waves: Enable long-range communication (thousands of miles) by reflecting the ionosphere.

Choosing the Right Frequency

  • Frequency selection depends on distance, time of day, and solar conditions.

  • Higher frequencies work better during the day,  lower frequencies are more effective at night.

Simplex/Duplex Communication:

  • Simplex: Same frequency for both transmission and reception.

  • Duplex: Different frequencies for transmission and reception, typically used for ship-to-shore communication.

Licensing

  • HF-SSB radio operation requires licensing for both the vessel and operator.

  • Training is highly recommended for effective operation of HF radios.