Messages from Space

Between Christmas and New Year's Day, 2020, the International Space Station is celebrating 20 years of ARISS (Amateur Radio on the International Space Station) by sending slow-scan TV images back to Earth. SSTV is something like a fax, sending one line at a time. To receive these images, you need an FM receiver tuned to 145.800 MHz. Unlike many other signals from space, you don't need a Yagi antenna. Because the signal from the ISS is relatively strong, the ground plane antenna I made worked just fine. The audio then needs to be sent to your computer for processing. I used an application called QSSTV. To know when the ISS is going to be overhead an iPhone app like SatSat works very well. There are web sites that track the ISS, too. Overhead passes come in groups of two or three per day spaced 90 minutes apart.

It took me three passes to get it right. 

For the first pass, I tried recording on my iPhone. I though I was recording, but alas, I wasn't.

On the second pass, I connected the radio output to my computer and recorded the signal with Audacity. I saved in several formats, but when I tried importing it into QSSTV, I got  an invalid header error.

On the third pass, I tried QSSTV in live mode with automatic save enabled. There are some noise artifacts because the pass wasn't particularly high above the horizon, but I did get an image. ISS been sending images of different contacts that have made and organizations they have worked with. This image shows astronauts on the space station along with members of AMSAT, the Amateur Radio Satellite Corporation. At the bottom are the Russian and American call signs used aboard ISS: RU0ISS and NA1SS.