Shopping centre PA pilot tone demodulated
As per request, AM demodulation of a 19.6 kHz PA system pilot tone heard in a shopping centre. Just to see if there's anything there.
0:12 : Sounds mostly like doppler from people moving, including myself.
0:25 : Some high frequency content from sibilants in an announcement in the adjacent audio band, but this is not encoded in the pilot tone amplitude.
0:52 : Footsteps as a child approaches me to ask for directions. I was standing quite still so as not to disturb the doppler effects.
See this tweet: / 1072536963637485569