As someone passionate about radio-technology and space, I decided to embark on an exciting project—downloading Low Resolution Picture Transmission (LRPT) and Automatic Picture Transmission (APT) images from NOAA and METEOR satellites, after reading an old article by Andre Phillips from UNSW working at the Siding Spring Observatory site in Coonabarabran.
Utilising the UHF/VHF TV antenna on my house roof and feeding it into an RTL-SDR v3, I was all set to capture some cool images from space.
Firstly, I used SDR++ to tune into the correct frequency. The software’s user-friendly interface made it easy to find the right settings. Then, using SatDump, I decoded the signals into actual images.
The decoding process is pretty clunky. As this tech was developed and left unchanged since the 70's. You start off with random beeping signals (the sync), and slowly, as the satellite begins to fly over Australia, the image begins transmitting live. Through a very iconic "Tick-Tock" noise. Essentially building the image using a form of morse code. I have attached a sample of the signal's audio below.
The images I've captured range from weather patterns to stunning topographies. Each pass of the satellite offers something new and exciting, making each capture a little treasure hunt.
So there it is, a glimpse into my escapade into space, right from my backyard. If you've ever wondered about the capabilities of satellites or simply wanted to experiment with technology, I highly recommend giving it a go. It's a fascinating way to connect with the universe from the comfort of your home.