>"WSPR transmits and receives but does not support normal types of on-the-air conversation. It sends and receives specially coded, beacon-like transmissions whi

>"WSPR transmits and receives but does not support normal types of on-the-air conversation. It sends and receives specially coded, beacon-like transmissions which establish whether particular propagation paths are open. Transmissions convey a callsign, station location, and power level using a compressed data format with strong forward error correction (FEC) and narrow-band, four-tone frequency-shift-keying (FSK)." [...] >"If you’ve wondered if a [ham radio, more broadly rf] band is open, WSPR can tell you." WSPR sounds somewhat analogous to 'ping' or perhaps 'traceroute' -- but for HAM radio (or more broadly, radio, rf) signal propagation paths... Related: https://vkradioamateurs.org/introduction-to-wspr/ https://vkradioamateurs.org/introduction-to-wspr/ >"The program can decode [weak] signals with S/N as low as −34 dB in a 2500 Hz bandwidth." https://www.sigidwiki.com/wiki/WSPR https://www.sigidwiki.com/wiki/WSPR https://en.wikipedia.org/wiki/WSPR_(amateur_radio_software) https://en.wikipedia.org/wiki/WSPR_(amateur_radio_software) >"Stations with internet access can automatically upload their reception reports to a central database called WSPRnet, which includes a mapping facility.": https://www.wsprnet.org/drupal/wsprnet/map https://www.wsprnet.org/drupal/wsprnet/map