Decoding Slow Scan Television Transmissions from the International Space Station (Listen to the Transmission Audio!)
From time to time the International Space Station (ISS) will activate their Slow Scan Television (SSTV) transmitter. April 12, 2018 was one of those times as the Russian crew commemorated Cosmonautics Day. Getting a SSTV image from the ISS is kind of like getting a FAX sent to you from a spaceship. In the case of the captured image above the ISS was transmitting an audio signal to Earth on a frequency 145.800MHz with 25 Watts. The signal is strong and lets anyone with some basic equipment receive and decode the image.
Now before you press play, I recommend turning your volume down but not off, just barely so you can hear, and then turning it up to suit your tolerance.