What frequency range is designated as High Frequency?

The frequency range designated as High Frequency (HF) is from 3 to 30 MHz. This range is significant in marine communication and navigation, particularly for long-distance radio communication. HF signals can be reflected off the ionosphere, allowing for communication over thousands of miles beyond the horizon, which is essential for maritime operations where ships often travel far from land.

This frequency range is commonly used for various forms of communication, including voice transmissions, digital messaging, and distress signals, all vital components of the Global Maritime Distress and Safety System (GMDSS). Understanding the HF range is crucial for operators to effectively utilize their communication equipment, particularly in emergencies or when traversing vast ocean areas where other forms of communication might not be available.