Listening to the Space Station

Sunday, April 12, 2015

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I was told that the International Space Station would be doing a broadcast of some SSTV images on April 12, 2015. The transmission was to celebrate the anniversary of Yuri Gagarin becoming the first human in space.

The transmissions were sent from RS0ISS, the Russian call sign on the space station, over 145.800 MHz FM using the SSTV mode PD180. There were twelve different images that were sent between 1000 UTC April 11 until 2130 UTC April 12.

Hardware Used

I used the following hardware to listen to the space station from my back yard.

Antenna Construction

I used the design by WB2HOL when building my antenna. I used the following parts when building mine:

That list might seem to be overwhelming, but take a look at the image from WB2HOL’s site below. Assembly plans should be clear now. If not, be sure to read his page.

Tape Measure Yagi Design

It’s a good idea to tape off the ends of the cut tape measure - they’ll be very sharp and you don’t want to hurt yourself.

Decoding the Images

I used Robot36 - SSTV Image Decoder (open source) on my Android phone. I had the volume on my UV-5R up high enough that it would activate the microphone on my phone. It was anything but a professional setup, but it worked!

Seeing as this was my first time listening for the space station, I was very excited when I saw anything at all. I’m pretty sure some of the interference you see is from me yelling “I got it!”. Next time around, I’d definitely want to use a hard link between the radio and the software to cut back on some of the interference.

Decoded SSTV Image

You can see how the image became more distorted as the ISS was going out of range. Unfortunately, my timing cut off the first bit of the image, but I was able to copy most of it. Even with all the noise, it was a great success!

For reference and comparison, this is a much cleaner reception of the same image (possibly a different transmission). The other images from this set are all online.

High Quality Copy

I also found a video posted by K7AGE of his setup receiving the same transmission. If you’re curious what SSTV looks and sounds like, click the image below to be brought to the video.

YouTube Link

I had a lot of fun doing this project; it was my first home-made antenna and I heard the space station on it. That’s enough of an accomplishment that I’m okay that the picture is grainy and incomplete. I hope to get back out there and maybe one day talk back to the ISS!

You can follow the discussions at /r/amateurradio, /r/space, and on Hacker News.