Electronics

ISS International Space Station SSTV

Markus Kolb

• 3 min read
ISS International Space Station SSTV

Today the International Space Station (ISS) has done some SSTV transmissions on 145.800MHz downlink.

Update: For part 2 see here!

Slow-scan television (SSTV) is a picture transmission method, used mainly by amateur radio operators, to transmit and receive static pictures via radio in monochrome or color.

A literal term for SSTV is narrowband television. Analog broadcast television requires at least 6 MHz wide channels, because it transmits 25 or 30 picture frames per second (in the NTSC, PAL or SECAM color systems), but SSTV usually only takes up to a maximum of 3 kHz of bandwidth. It is a much slower method of still picture transmission, usually taking from about eight seconds to a couple of minutes, depending on the mode used, to transmit one image frame.

Since SSTV systems operate on voice frequencies, amateurs use it on shortwave (also known as HF by amateur radio operators), VHF and UHF radio.

I've used my Software-Defined-Radio-Receiver (SDR) and some programs on my laptop to receive some images.

There is a YouTube video about the receiving.
And the quite good receive of the 7/12 pic.

The weather conditions with thick clouds and much rain during the whole day has not been so gainful for radio transmissions in VHF from the ISS down over 400km to my antenna.
It is a self-made 5/8-Lambda vertical.
I've used Gpredict software to control the frequency shift.
The analog SSTV transmission signal was decoded by QSSTV.

The information about the transmissions I have found on the ARISS-SSTV blog. And also on the UK Amateurradio Satellites blog AmSat-UK.

Russian cosmonauts on the International Space Station (ISS) are planning to transmit Slow Scan TV images on 145.800 MHz FM using the SSTV mode PD-120.

The transmissions are part of the Moscow Aviation Institute SSTV experiment (MAI-75) and will be made from the amateur radio station RS0ISS in the Russian Service module of the ISS.

Around 17:10 UTC a new round started with this unfinished picture...

But the next one is a nearly perfect picture...

Soyuz T-7 Crew end of 1982

Up-to-now this is all I could receive.

Based on the announcement of the ARISS press release there should be starting a question&answer session between students and astronauts. But since 17:47 UTC there seem to be a problem with the radio on the ISS. We'll see if it is fixed later or tomorrow, if I can receive some more SSTV transmissions.

A screen recording during receiving of some SSTV transmissions from Internation Space Station (ISS).
  • Crew Soyuz T-7 – 19 August – 10 December 1982
    • Leonid Popov
    • Aleksandr Serebrov
    • Svetlana Savitskaya

Update: For part 2 see here!