An innovative space transmission system built by volunteers has started sending down pictures from the international space station to the whole wide world via amateur radio. Thanks to SpaceCam1, anyone with a police scanner or a suitable radio rig, plus a computer and the appropriate software, should be able to receive pictures from orbit, the project's organizers say.
The SpaceCam1 slow-scan television system, which combines a couple of hardware gizmos plus the signal-coding software on one of the station's laptop computers, has been three years in the making. The project follows up on a less sophisticated system that was tested aboard Russia's Mir space station in its waning years.
Space station commander Pavel Vinogradov looks
into the camera while he operates the SpaceCam1
system on his laptop, visible in the background.
"It's been fun, and this is just a steppingstone," said Miles Mann, project lead and chief executive officer for the MAREX amateur-radio club. MAREX was involved in the Mir project - and it teamed up with another volunteer group, Amateur Radio on the International Space Station, for SpaceCam1's next-generation SSTV system.
SSTV basically means snapping a digital still image and translating the scan lines of that image into a sequential stream of data. That stream can be transmitted on a radio frequency, then decoded on the other end to reconstitute the digital image.
On the space station, the original image can come from something as simple as a Webcam, hooked up to an onboard laptop. Astronauts can point the camera at themselves, at the station interior or just set it up at one of the station's windows for a view of Earth below.
The data conversion is done through software on the laptop plus a little hardware interface known as a "VOX box." Then the data is beamed down to Earth via a radio transmitter.
Down on the planet, you can tune your scanner or radio receiver to 145.800 mHz on the 2-meter band, pick up the signal, have it converted automatically on your own computer ... and voila! you've made contact.
This SpaceCam1 picture shows NASA astronaut Jeff
Williams, Russia's Pavel Vinogradov and Germany's
Thomas Reiter, flanked by empty spacesuits.
The equipment and the software was sent to the station last September on a Progress cargo craft, and since then the space station astronauts have been working off and on to get the system running. On July 30, they sent the first still image - and at least two more have come down since then.
Farrell Winder, a retired electrical engineer who is part of the SpaceCam1 team, said the system was still being adjusted for the optimal operating mode. After the shakedown, the camera can be set to run even when the astronauts are off doing something else.
"We have great confidence that it's going to give us hundreds of pictures a day," he said.
And that's just the start. Eventually, the system will be able to receive pictures sent up to the station from licensed ham-radio operators, Mann said.
SpaceCam1's first picture from orbit shows the space
station's Expedition 13 logo mounted on a window,
with a solar array and Earth's glare visible outside.
Mann is already dreaming of the day when a SpaceCam can be fitted aboard a moon-bound spacecraft, to serve as a transmitter or even as a relay for earthly transmissions. A fair number of radio enthusiasts are already bouncing their signals off the moon to reach faraway earthlings, Mann noted.
"We'd be able to increase the number of people who can do that tenfold," Mann told me.
For the record, here's the full release from the SpaceCam1 team:
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