Tutorial HF digital FT8 and WSPR

Weak amateur signals, decoded slot by slot.

What you need

• A radio that tunes HF (an RTL-SDR in direct sampling, an SDRplay or an Airspy HF+ are common; a HackRF needs an up-converter) and an HF antenna.
• A computer clock that is right: FT8 uses 15-second slots. OnAir can sync the computer clock from GPS or a time station.

Steps

1. Choose FT8 (group Amateur: digital). The dial frequency is 14.074 MHz upper sideband; other entries have their own: FT4 14.080, FT2 14.084, WSPR 14.0956 MHz. The band buttons jump to the usual frequencies of other bands.
2. Press Start. OnAir decodes every signal in the 3 kHz passband at once; since 0.2.5 you can also decode every signal in the visible span, not just the tuned one.
3. In Decodes every message appears with its SNR; Map places stations by their grids; WSPR has WSPR spots.
4. Press Listen to play the audio of the passband.
5. Export with Save results... as CSV or an ADIF logbook (call, grid, band, mode, RST / SNR, UTC).

Reporting your spots

Both are optional and off until you turn them on. Spots are public, so use your own valid amateur radio callsign.

• PSK Reporter (View > Data feeds): sends the stations you decode to pskreporter.info. Reports are batched every 5 minutes and the same station on the same band is sent once per 10 minutes.
• WSPR spots upload to wsprnet.org (0.2.6).

More modes in the same family

JT65, JT9, Q65, FST4 (and FST4W), MSK144, Olivia, Contestia, MFSK, THOR, DominoEX and Hellschreiber have their own entries in the mode list. See the mode reference.

Related: FT8, WSPR, JS8Call, PSK31, CW, Hamlib rigs.