kortvågen

Kortvågen, meaning "shortwave" in Swedish, refers to radio waves with wavelengths ranging from 10 to 100 meters, corresponding to frequencies between 3 and 30 megahertz. These frequencies fall within the High Frequency (HF) band. Shortwave radio has historically played a significant role in long-distance communication due to its ability to propagate over vast distances.

Unlike very high frequency (VHF) and ultra-high frequency (UHF) waves, which tend to travel in straight lines and are limited by the Earth's curvature, shortwave signals can be reflected by the ionosphere. This ionospheric reflection allows them to bounce back to Earth at distant locations, enabling communication across continents and even globally. The effectiveness of this propagation, however, varies depending on factors such as the time of day, season, and solar activity, which influence the state of the ionosphere.

Historically, shortwave broadcasting was widely used for international radio services, news dissemination, and even by governments for propaganda and intelligence purposes. Amateurs, often called "hams," also utilize shortwave frequencies for recreational communication and emergency preparedness. While newer technologies like satellite communication and the internet have reduced its prominence for some applications, shortwave radio remains relevant for certain niche uses, including maritime communication, aviation, and by those seeking to receive broadcasts from remote regions. The simplicity and robustness of shortwave technology also make it valuable in situations where more advanced infrastructure may be unavailable or damaged.