Listening to the Space Station
Sunday, April 12, 2015
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.
I used the following hardware to listen to the space station from my back yard.
- Baofung UV-5R ($30 on Amazon)
- A SMA Female to UFH Adapter ($3 on Amazon)
- Android phone for decoding (other software would have worked, too)
- Homemade Two Meter Yagi (See below for parts list)
I used the design by
WB2HOL when building my antenna. I used the following parts when building mine:
- (1) 0.5" x 8" Schedule 40 PVC
- (1) 0.5" x 12.5" Schedule 40 PVC
- (2) 0.5" Schedule 40 PVC Cross
- (1) 0.5" Schedule 40 PVC Tee
- (1) 10' tape measure, 1" thick
- (6) 1.5" Stainless Steel Hose Clamps
- (1) 4.5" wire for the hairpin match
- (1) 0.5" x 2' Schedule 40 PVC (used for the handle)
- Sandpaper or griding tool to prepare tape measure for solder
- Electrical Tape
- Soldering Equipment
- Coax (enough to go from the middle element to your receiver)
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.
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.
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.
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.
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!