I'm trying to learn more about RF signal modulation/demodulation. I wanted to experiment with some real signals, but I don't have any data to work on.
Is there any open database of RF signals? Like a set of signals with known characteristics modulated with AM, analog FM, digital QAM, ... Raw data (directly from ADC) would be perfect, so I can do all decoding stages myself.
I tried to look for it on google, but I couldn't find it anywhere.