DIY Friday: Weather Satellite Station
Sick of weather.com’s pop-up ads?
Setting-up a weather satellite station is remarkably simple: Connect a discone antenna ($50-100) to a PC-controlled receiver (HobbySpace used a ICOM – PCR1000 – now a 1500). The receiver includes software to receive the audio signal. You will need software to decode the audio to obtain the weather image. HobbySpace used WXSat (freeware). More advanced station designs are available here.
You can use WinOrbit to track when and where a polar satellite will pass. By the way, these polar satellites work a little different than your typical weather satellites that show weather patterns moving across the country on your local news:
The NOAA polar satellites orbit at 850km and pass within view of all areas on earth at least twice day. The satellite carries a number of instruments including cameras for both visible and Infrared light.
The cameras scan back and forth at right angles to the ground path, like a broom sweeping side-to-side as you walk forward, taking picture strips that cover an area 3000km wide. The satellite thus makes a continuous picture as if it was a tape reeling out from an endless roll.
The image, however, is not recorded on the satellite. Each image strip is immediately broadcast to the ground at a frequency just above 137MHz. The satellite will be in range for up to 12min as the satellite passes from horizon to horizon.
The broadcast uses the APT (Automatic Picture Transmission) analog format for the imagery. (A digital format – High Resolution Picture Transmission (HRPT ) signal is also transmitted but it is more difficult to receive and decode and we did not try to receive it in this project.)
Want the whole shebang? Build an ethernet weather station to collect temperature and air pressure readings, then feed the data through its very own web server.
And, if you’re looking for a location for your new venture, consider my old stomping grounds – southern Wisconsin. Among the bizarre events in the past few weeks: first Severe Thunderstorm Warning in 14 years during the month of January; numerous rivers exceeding flood stage…in JANUARY; and record high January temperatures throughout the area. Crazy. We’ll save the global warming debate for a different day. Let me just say I’m glad I did my cross-country skiing in December and not January.
