WebSDR is a Software-Defined Radio receiver connected to the internet, allowing many listeners to listen and tune it simultaneously. SDR technology makes it possible that all listeners tune independently, and thus listen to different signals; this is in contrast to the many classical receivers that are already available via the internet. See more and try it for yourself at http://websdr.org/
From 3:08 you can hear Earth-Moon-Earth (aka moonbounce) communication where the radio signals are reflected by the moon.
oz9aec 2 years ago