Made a recording of the FUNcube-1 (AO-73) satellite this morning. Here it is, direct to you from space
You can hear the Doppler effect. The satellite is passing by a few hundred km away, so at its closest it’s neither approaching nor receding. As time passes it’s receding faster and faster from the receiver (though still at about the same speed in space) so we get the pitch of the sync frequency going down. Just like a fire engine or ambulance siren passing in the street!
If you listen carefully you can hear the sound of the “noise” between the beeps – it’s actually data – changing in pitch as well. It’s more noticeable at higher frequencies, and is hard to hear because it’s an approximation to white noise.
