You can also get with some more work the much higher resolution HIRT images from the GOES sats. It's kind or fun to mess with. I used it as an excuse to mess with offloading the error correction to an FPGA, which was fun but also totally unnecessary.
We used to do this back in the mid 70s, we built a VHF receiver (and someone outside in the frost with a big antenna listening to the noise floor and tracking) - the signal was an analog FSK (you can kind of imagine it as a single light sensor and the satellite spinning, getting 1 scan line per revolution) - we'd feed the signal to a TV in a dark room with a manual vertical sync button, and with a camera pointing at it.
As the signal started someone would press the sync button and someone else would open the camera shutter when the pass was done we'd close the shutter and wind the film on, we'd get 2-3 passes a night,at around midnight we'd develop the film.
There was also a much faster broadcast around midnight from a geostationary satellite - 12 images (4 around the equator and 4 around the poles) with the communist countries carefully blanked out, you had to change the scanning rates and be nimble with the camera.
It was fun and the alternative was a close to $1m fax ground station (this was before faxes were something most people had even seen)
This was a home built circ polarised yagi (it was VHFish/UHFish, I forget the freq), it was big and a bit unweildy (a bit of 2x4 bolted to an upright) but not giant and not a dish
Wow, if you zoom in really far, the resolution seems to exceed that of Google maps. I can make out shingles on roofs of homes, so it must be what, a quarter foot res?
I think this is really cool, I'm genuinely curious if there's any advantage of it versus getting the image from NOAA's website?
In other words, is there any data or imagery gathered this way that you can't get from NOAA? (I realize there would be a slight delay before the imagery is available from NOAA).
I'm not trying to take anything away from this awesome project, I'm just curious.
It's useful for places where there is no internet connectivity, or where connectivity is very expensive. For example, ships at sea, to whom this sort of information is most important.
I've been trying to do this with my son for a few weeks. I haven't been able to get any of the Mac compatible SDR tools to work with Catalina. I haven't tried it yet but our next step is using GNU Radio with a RaspPi
When you're picking up a radio-facsimile transmission, you're picking it up from a ground-station that's transmitting a weather forecast product that's generated by the National Weather Service and intended for reception with consumer-level technology.
What's described in the article is receiving raw imagery directly from the satellite; so it's not really the same thing.
It’s just a very thorough doc that takes you from zero to hero. The process is extremely simple. I used to do this back when the RTL SDR stuff just started and the ridiculously bad antennas that i built that still worked were pretty remarkable.
It blew my mind back in the 80s when I read an article on how to get my humble home computer receive satellite maps. Unfortunately I didn't own a shortwave radio and I couldn't convince my parents to buy one because the weather was already on the local news every night.
This is the image direct from the satellite rather than a rebroadcast. You see what the satellite sees as it passes over in realtime.
WEFAX is still a thing from what I can tell, but I haven't been able to pick anything up yet as I suspect my "random wire" antenna doesn't have enough random wire yet.
Shortwave is really tough in urban environments these days because of all the electrical noise from poorly-designed electronic devices. If you live in a single family home, try turning off your power at the breaker box, powering your radio off of a 12 V battery, and see how well you can do. Alternatively, take your station to a rural campground.
https://pietern.github.io/goestools/guides/minimal_receiver....