DIY Satellite Ground Station to Receive NOAA Images | Hacker News Reader

DIY Satellite Ground Station to Receive NOAA Images

publiclab.org

162 pointscromulent34 comments

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.

https://pietern.github.io/goestools/guides/minimal_receiver....

That’s super tempting, those pics are gorgeous.

I'm looking to get into this sort of stuff for fun, do you have a resource where you started to learn all about it from?

Also would you say that using the gear that was specified in OP's post you could achieve the same results you got?

Thanks

A crash course on hacking satellites: https://news.ycombinator.com/item?id=24072829

The parabolic grid antenna in that link does not appear to be available

Do you happen to be located in CA?

You can get by with one designed for 2.4GHz wifi if those are easier to acquire. They were < $50 on Amazon when I did my build a year or so ago.

Just have to flatten the front a bit and push it out by about an inch. I used a short piece of pvc pipe and some zipties.

If anyone in the bay area is interested in this. I will give you my grid antenna and Nooelec goes+ LNA!

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)

> (and someone outside in the frost with a big antenna listening to the noise floor and tracking)

I've wondered about this, why were consumer satellite dishes so huge back in the day, and now we seem to be able to get away with much smaller ones?

Is the transmitter power on to he satellites higher than it used to be? Or is it better receiver electronics? Or better algorithms/codecs?

Yes, all three in combination. GaAs PA, low cost GaAs LNA, and Turbo coding are what made it possible in the 90’s.

You’ll notice that many dishes are wedged shaped than circular. This is to keep the beam width under the 2 degree spacing of geostationary satellites.

Also we have increases the frequencies that we use. Back then it was C-Band, now everyone is using Ku or higher.

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

https://zoom.earth if you just want to see the recent images.

Good note (+1)

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?

The detail there is incredible. Anyone know if it's possible to import this imagery into QGIS?

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.

Are images received from satellites like this free to use, or does some license apply?

Imagery that the government chooses to release is typically public domain. Our tax dollars at work.

Free, usually. AccuWeather tried to change that a number of years ago, but they failed. Thankfully.

If you like this, there's a subreddit for you: https://www.reddit.com/r/RTLSDR/

Other NOAA-related projects: https://www.reddit.com/r/RTLSDR/search?q=NOAA&restrict_sr=on...

And if you want to put that RTL-SDR to a specific use by tracking airplanes, you should check out https://www.reddit.com/r/ADSB/

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

Have you trying installing GNU Radio via macports? That may help.

https://wiki.gnuradio.org/index.php/MacInstall#Prerequisite:...

This seems like a lot of work.

We used to do this with a $30 shortwave radio and a Commodore 64.

Maybe the NOAA WEFAX transmissions aren't in shortwave anymore?

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.

Good times, I've done this with DWD (German meteorological service) in the 90s, using HamComm [0]

This project in the article however, listens directly to satellites, and not to a LF/HF ground-based station like we used to do.

[0] https://www.pervisell.com/ham/hc1.htm

Oops, lost my memory there for a bit: it was probably using the same DIY "Hamcomm modem", and using JVFAX (or similar) software running under DOS.

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.

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 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.

One of the early articles on the subject is a fun read: https://archive.org/details/198502Rainbow/page/n41/mode/2up

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