Last week the International Space Station was transmitting Slow Scan TV (SSTV) Pictures for a few days.
Initially they had some teething problems with the transmissions which meant I ended up standing in the garden pointing my Yagi antenna at the sky wondering why I wasn’t picking anything up !!
One of the biggest problems with anything involving satellites (or space stations) is that they don’t stay still and you only have a few minutes to makes sure everything is working and to see what you can get. If something goes wrong then it is hours (or even the next day !) before you can try again. The way that the peace station orbits means that on a “good” pass you have about a 7 min window from it appearing above the horizon, going overhead (or in an arc past you) before it disappears again. One of the other problems I have where I live is that I have a few hundred feet of solid chalk quite close to me that tends to block the signal until the space station is quite a bit higher….
None the less I thought I would give it a go to see what I could pick up. I had my MacBook Pro connected to the audio output of the radio (with a bit of a mix of cables to get the audio out to be recognised as a mic input via USB…). Initially I connected up my Yaesu FT1DE Handheld to see how well that worked but I did switch to my Yaesu FT-817ND and I did see some improvement in the signal received. In both cases I was using the Yagi Antenna that I made a few weeks ago from some plastic pipe and a metal tape measure 🙂
I used the ISS Finder app on my phone to tell me when the space station was due over and the path it would be taking. I then held the antenna up and pointed it roughly where I thought the space station would be. When it picked up a signal I watched the signal strength meter and moved the antenna to keep the signal as high as I could.
The software that I used on the mac was Multiscan 3B. This enabled me to receive and decode the image. Luckily this was quite easy to setup and did automatically pick up the start of the transmissions. Between each transmission there is a silent gap of a couple of minutes so you only really get one chance per pass to get anything !
This is the first image I received.
There is something quite cool about watching this appear line by line on your screen knowing that it has come to you directly from a space station !
Later that evening I took all my kit to Worthing and District Amateur Radio Club for their weekly meeting. It looked like there was going to be a good pass that evening so a chance for us all to see it !
Luckily it was a really clear evening. I set everything up on the boot flap of my Smart Car and we waited…. I had a willing volunteer hold the antenna and a whole host of space station spotters 🙂 Not long after we spotted the space station in the sky we started to receive the image. There was some local interference but luckily not too much….. It was amazing being able to see the space station fly across (it is quite bright and quite fast…) and this made tracking it with the antenna much easier. I had the volume turned up on the radio so we could hear the data come in as well as see the image appearing on screen… As we lost sight of the space station behind some buildings I was about to start packing up and we started to receive a second image. This was only a partial image because the space station was going out of range below the horizon..
So, thank you to Tim Peake and everyone involved in the transmissions. I think it is fair to say that you made a bunch of “geeks” quite happy 🙂
The first image was the one captured that evening and the second image is the partial image received. The transmissions have now stopped and I don’t know if or when they will be live again…