What frequency range is referred to as HF?

HF stands for High Frequency, and this designation corresponds to a specific range of radio frequencies in the electromagnetic spectrum. The HF band is defined as the frequency range from 3 to 30 MHz. This range is significant in amateur radio as it is well-suited for long-distance communication through ionospheric propagation. Signals in this range can reflect off the ionosphere, allowing them to travel beyond the horizon and reach distant locations.

The other frequency ranges mentioned do not correspond to HF. For example, the range of 300 to 3000 MHz falls within the UHF (Ultra High Frequency) or SHF (Super High Frequency) categories, and the range of 30 to 300 MHz typically corresponds to VHF (Very High Frequency). Meanwhile, the range of 300 to 3000 kHz is in the lower frequency spectrum, commonly associated with Medium Frequency (MF) broadcasting. Understanding these classifications helps amateur radio operators select the appropriate frequencies for their communications and activities.