VE6DOK · HF Overview
Understand what HF radio is, why it works, and why conditions change.
This page gives the foundation before moving into deeper HF operating and propagation tools.
What HF is
HF means high frequency, generally 3 to 30 MHz. These bands can travel far beyond line-of-sight by reflecting or refracting through ionized regions of the upper atmosphere.
Beginner view
HF lets you talk beyond local repeaters. Band conditions change throughout the day.
Intermediate view
Solar flux, Kp, time, season, path, and antenna height affect results.
Advanced view
Operators combine propagation data, station capability, noise, and path geometry to make better decisions.
How HF differs from VHF/UHF
VHF/UHF are often line-of-sight and repeater-based. HF is more dependent on the ionosphere, time of day, solar conditions, and antenna efficiency.