WSPR

[pxr5]

I've just watched Why Planes Vanish: The Hunt for MH370 on the BBC (it's a really good watch btw ) and near the end it describes how an ex Avionics Engineer used tiny disturbances in these Weak Signal Propagation Reporter (WSPR) signals to locate, where he thinks, MH370 entered the Indian Ocean (which is just outside the original arc search area). WSPR is used by amateur radio users for measuring transmission propagation. It's amazing technology that was created and used by radio enthusiasts (even something as simple as a Raspberry Pi can be used). I have a background in HF transmission and radio comms and this still blows my mind. Hopefully, a new search can commence using this new data to find the plane. I find this all fascinating.

https://en.wikipedia.org/wiki/WSPR_(amateur_radio_software)