Track aircraft (ADS-B)

Aircraft broadcast who and where they are on 1090 MHz. ./devkit adsb receives them with the board, decodes them on your PC and shows one row per aircraft. It never transmits.

1. Put a 1090 MHz antenna on RX1A (or RX2A, then add --channel 2), outdoors or at a window with a view of the sky. Aircraft are line of sight: walls and hills cost more range than anything else.
2. Power the board from a mains charger: on bus power it hangs under a sustained 4 MSPS stream, which is all this tool does.
3. Run:

# run from: the repo root, on your host PC (not the board)
./devkit adsb                  # the antenna on RX1A
./devkit adsb --channel 2      # the antenna on RX2A

You should see: a table of aircraft with callsign, altitude, speed and position, above a log of every message. Daytime near any airway usually gives several within a minute, with an outdoor antenna.

# run from: the repo root
./devkit adsb --text                     # messages, plus a table every 10 s
./devkit adsb --record flight            # flight.sigmf-data + .sigmf-meta
./devkit adsb --replay flight.sigmf-meta # no board needed

The table stays empty?

Symptom	Fix
LINK TOO SLOW	--uri ip:192.168.2.1, or export BOARD=192.168.2.1
NO SAMPLES for N s	power it from a mains charger, then check ./devkit status
rejected rises, nothing CRC ok	check the antenna and its cable, then try a few dB less or more gain
"something else holds the receiver"	close SDR++ or the capture; only one program can stream at a time

Settings, positions and how the decoder works: ADS-B.