With a cheap RTL-SDR dongle and an antenna you can receive ADS-B — the 1090 MHz signal aircraft broadcast with position, altitude, and ID — and plot live traffic overhead.
How it works
Aircraft transmit ADS-B constantly. readsb decodes the 1090 MHz Mode-S frames into positions you can map (tar1090) or share with networks (FlightAware, ADSB.lol).
readsb --device-type rtlsdr --gain 49.6 --net --write-json /run/readsb
One dongle, one job
A receiver typically runs ADS-B 24/7, which means that dongle is busy and can't be used for other bands at the same time. To also capture weather satellites, use a second dongle or schedule around each other.
Antenna matters most
| Setup | Range |
|---|---|
| Stock antenna | A few dozen miles |
| Tuned 1090 MHz antenna | 100+ miles |
| Outdoor + LNA + filter | 200+ miles, clean |
Related: Weather Satellite Imaging with NOAA and Meteor · Home Lab Fleet Architecture