How the live map works
Everything on the live page is generated automatically from public data. This page explains where the numbers come from, how paths are classified and what the limitations are, so you can judge what you are looking at.
Where the data comes from
- Reception reports come from PSK Reporter, a network that collects automatic reports from receiving stations around the world. When a station running software such as WSJT-X decodes a signal, it reports who it heard, where, on what frequency, in which mode and at what signal-to-noise ratio. DX6 requests all reports between 50 and 54 MHz from the previous 15 minutes, once every five minutes.
- DX cluster spots are provided by HamQTH.com. These are contacts and signals posted by operators by hand, and they often include SSB and CW activity that automatic networks miss.
- Space weather comes from the NOAA Space Weather Prediction Center: solar flux, the planetary K index, GOES X-ray flux, solar wind speed, the interplanetary magnetic field and the NOAA space weather scales.
How paths are drawn
Each reception report includes the Maidenhead grid locator of both the transmitting and receiving station. DX6 converts each locator to a point at the center of the grid square, then draws the great-circle path between them, which is the shortest route over the Earth's surface and approximately the route the signal travels. Repeated reports between the same two stations are combined into one path. Reports without valid locators are skipped.
The shaded area shows the night side of the Earth, calculated from the sun's position at the moment you load the page, with a lighter band for twilight. The boundary is the gray line.
What the colors mean
Paths are colored by distance, because distance is the best single clue to the propagation mode:
| Distance | Most likely mode |
|---|---|
| Under 900 km | Tropospheric, ground wave, meteor or Es backscatter, short-skip Es |
| 900 to 2,300 km | Single-hop sporadic-E |
| 2,300 to 4,600 km | Double-hop sporadic-E |
| 4,600 to 8,000 km | Multi-hop sporadic-E or trans-equatorial propagation |
| Over 8,000 km | F2, long multi-hop Es or TEP combined with Es |
Distance alone cannot prove the mode. A 1,500 km path is almost always sporadic-E in summer, but could be meteor scatter or aurora under the right conditions. Use the space weather panel and the time of year as extra clues.
How possible TEP is flagged
A path is marked as possible trans-equatorial propagation when its two ends lie on opposite sides of an approximate geomagnetic equator, the path runs mostly north-south, and its length falls between 3,000 and 9,500 km. This is a geometric test, so it identifies candidates rather than confirmed TEP.
Band status and counts
The band status counts distinct paths longer than 900 km in the last 15 minutes. Fewer than 10 is shown as weak, 10 to 59 as open and 60 or more as wide open. The continent matrix assigns each end of a path to a continent from its coordinates; boundaries are approximate. The 24-hour chart stores one sample each time new data arrives.
Limitations
- The map only shows paths where someone was transmitting and someone else was listening and reporting. Quiet areas may be open with nobody active.
- Most automatic reports come from digital modes, especially FT8. SSB and CW activity appears mainly through cluster spots.
- Coverage is densest in Europe, North America and Japan, where most reporting stations are located.
- Source data occasionally contains wrong locators. A single implausible path should be treated with caution.
- If a data source is unavailable, the page keeps showing the last good data and marks it as delayed.