If you’ve ever wondered about the planes flying overhead, you can always listen to ADS-B transmissions to learn more about them. [thefatmoop] built a rig to do that, and it comes in under $50 in parts.
The build is based on the Meshnology W12 board, which combines an ESP32-S3 microcontroller with an LR2021 LoRa radio. The latter is capable of being tuned into transmissions in the 1090 MHz range and it can capture ADS-B traffic that uses OOK and Manchester coding. The data is passed to the ESP32-S3, which validates the CRCs of the captured data and serves the flight paths on a simple web interface. A GNSS receiver can also be added so that the board knows its own location as well as the position of the aircraft it is tracking.
[thefatmoop] reports decent performance with the rig, pulling aircraft tracks from up to 150 nautical miles away with a 915 MHz antenna. There are some mods required to achieve this performance, however – namely, you’ll want to change the filter configuration on the board to avoid it weakening the 1090 MHz signals of interest.
There are many other ways to listen to ADS-B signals, too – you can always grab an SDR and get going. If you cook up your own cheap radio hacks, don’t hesitate to let us know on the tip line!
Thank you [Moser] for the tip!