
The map above was generated using G7RAU’s Live MUF application. It’s showing the latest FIVE MINUTES of activity. The map uses Great Circle azimuthal equidistant projection. The page is automatically refreshed approximately once per two minutes but system lags may cause the map shown to be 5-10 minutes old. Roughly 30-50,000 contact lines are drawn per hour. The “spots mapped” information shows the number of lines plotted in the current five minute period. Actual contacts can take place via the long or the short path around the world, but the map will always show only the short path between stations, despite some lines appearing to wrap around the globe.
The data source for this map is (indirectly) PSK Reporter and other skimmer servers. These are automated reception reporting system reporting on WSPR, FT8, FT4, MSK144 and some other digital modes. Transmitters tend to be very low power (<5W or even only a few mW for WSPR). Reports are plotted for all HF amateur bands using colours to denote each band, as shown in the colour key.

Solar flares can often cause intense bursts of X-rays to be blasted towards Earth. When they strike the atmosphere the ionosphere becomes highly ionized, which can cause severe radio blackouts due to noise on the HF frequencies. Blackouts can also affect VHF, UHF and higher frequencies by creating high levels of noise.
Contact paths remain visible on the map for five minutes before being erased.
*The path plots are reliant on the correct locations existing in various databases for the tens of thousands of radio operators. These are not always correct and errors do occur, so don’t be surprised by the odd few crazy dx lines appearing on the maps!