How to Pull Images from Satellites in Orbit (NOAA 15,18,19 and METEOR M2)

every second of every day thousands of objects pass overhead and yet we are never noticed at least not directly since the dawn of the Space Age we've been hurling machines in orbit on a very regular basis and at any one moment there could be dozens from above you now before you thought that the tinfoil hats know that these machines aren't usually tools for watching them eat a sandwich in the garden from TV and telecommunications to weather imaging and more satellites play an extremely vital role in our society of all their uses TV is probably the one were most familiar with so you already know that it's possible to pull information from satellites but for most people that's sort of where it ends recently I got a chance to work with art of lifting images with a degree in cybernetics in computer science is work never ceases to amaze me from cameras that can be found to robots plasma speakers computer vision and more he's done a little bit of everything I put links to stuff in the description I'd highly recommend checking oil when we met up we were talking about the various bits of hardware we hit and Chad and started thinking of uses for each eventually he mentioned he brought a hack RF which is a software-defined radio I was already excited because since my experiments with the LS radio I wanted to play around performance but then you mentioned that we use it to pull information off of weather satellites as they passed overhead so they I love the idea is an understatement so we started thinking into what an actions it takes to do that terms they're actually really easy there are four satellites that we'll be looking at in this video first the olders NOAA 15 and 18 and 19 satellites and then be much newer meteor m2 satellite the NOAA satellites or NOAA for short broadcast an analogue signal where every beep encodes a single line of image whereas meteor broadcast a digital signal that has a lot more data errors as such images from NOAA satellites come in at point where as media religious committed both colors the first thing you'll need is the software-defined radio we're using a hack RF but there are lots of other models for the work just as well I ordered one of them to try out which you'll see in a future video the next thing you'll need is an antenna this is the point where you have locks optional the simplest kind of antenna is called the die place to build one you need to be who you are that can support their own weight here we're using galvanized gardening wire and a stick to secure a pencil will do it efficient then you'll need some 50 ohm coax cable and the appropriate connector to get to attach it to your FDR Apollinaire click here we're using a small SMA collapse connector Rio is part of the electromagnetic spectrum and as such is made of electromagnetic wave as these waves tapped with the gospel they induce a slight oscillating charge of the wires and our signal is encoded in these oscillations but for this type efficiently the length of the wires must be cut to very specific lengths they're in tune with the instrument wave this is sort of analogous to how it started between to make the right sound generally you want each of the two wires to be one quarter of the length of the wave and the two together to be one half the length of the wave or one half of wavelength for this experiment we need an infinitude to about 137 mm that's the frequencies of the satellites broadcast back luckily most antennas work well within 50 percent efficient of frequencies so if we build an unfinished or what it'll still work well for several dozen megahertz in either direction and frequency and wavelength are related we can figure out how long the wires should be using some simple math or an online calculator so for 137 megahertz one quarter of the wavelength is 52 centimeters so we cut two pieces of wire to that length and this was our first test we taped ours together using some electrical paste put the alarm things up and it looked up when the next satellite pass one we use the site which I've linked in the description but there's also lots better tools to let you do this like orbit ron's luckily the pass was in the next 20 minutes shall we head it outside to try and catch it this is a first experiment we cannot the antenna on so I just held it in the air careful not to touch either of the wires we open up the FDR program in this case F G sharp and start watching sure enough right satellite controls be over the horizon a signal showed up the lower part of the screen for the waterfall and we need the distinct strontium token signal or the analogue satellite when we were done recording we tried to decode the image with some software we found online but the signal quality was far too low but that's okay because we had successfully detected the satellite and knew we were on the right track we spent the next two days looking into other antenna design first we tried to use an umbrella because each shade of the umbrella is actually perfect for doing stuff like this but he's worked really deep rooting on the umbrella preventative support will trap it again in the future video once we can find a better umbrella next we tried to build a helical Quadra filler antenna the planetary can be found online and I put a link in the description unfortunately this antenna didn't work so well so I won't go into too much detail about how we built it if not say that these antennas can't work we just didn't have the parts to build a nice one we may try again in the future video for this antenna we found a wooden pole lying on the side of the road to act as and support we cut more wire this time far longer than bent and twisted the wire into a helix terms out the angles of everything are really important and this is one of the reasons why the antenna didn't work so well at first we had lots of sharp corners in the wire and if helix wasn't quite the right shape so our reception was about as good as the pencil also these antennas are supposed to be omnidirectional but because ours wasn't built quite right it we found we had to be pointing directly at the satellite as it moved well this look really cool because we were tracking a thing moving many kilometers per second through space it made for really inconsistent signals we tweaked and improved and after several attempts we got our first piece of an image it was only a sliver but this is a definite detail shortly after this we decided it was time to upgrade the antenna again this time we decided to go with something that should be both simpler to build and properly on the directions so we don't need to point directly at a satellite for this we decided to build a double-crosser antenna it's basically score dipoles mounted in pairs across from each other and tilted to 30 degrees they're tilted because the radio signal coming from the satellites is polarized in this case right-hand circularly polarized if you typically dipoles the wrong direction the signal won't be able to properly interact with the antenna to build it we first disassembled our last antenna so that we could salvage the pole then we have some of our students down but first straighten it and then cut the wire we need to lay we need eight pieces each 52 centimeters long and as straight as possible we added a little dance to the end of each wire so that we could more easily attach the wiring to them later instead of pencils we use small wooden dowels each cut about a football the length isn't critical to be enough to support the wires can be thick enough to allow us to drill a screw through it later then we assembled our four dipole to the clear packing tape I'm sure there are better ways to do it but we use what we had on hand then we cut across the boards for the top these are just two pieces of wood cuts 27 metres in length we drilled the hole to the center of each piece put a screw through the middle and mounted it to the top of the pole in a cross pattern we mark the center of each of our dipoles then attach them to each side of the cloth using a single screw I later added a second screw next week so that the dipoles can only tilt to 30 degrees and no further that way if they get bumped it used to reset them with everything now did we move down to the wire when we first did this we realized we didn't have enough coax and rather than wait a day and go get more we used some random coax we found lying around that was meant for kind of like TV this ended up being a big problem and we have to fix later if you try and build this don't do that use copper 50 on coax represents the wiring had a bunch of really specific requirements like the length of each piece of coax and how to connect everything ensure if you need two pieces of coax cut to one quarter the length of a wave and two pieces cut 1/2 the length away this is because we need to delay the signals coming from one pair of dipoles so that everything lines up properly on the output I won't go into more detail here but if link to a great document on everything you need to know in the description including the lengths of the wires and how to connect 2 percent we first soldered all the coax on the deny poles and then to each other and tried to make sure that nothing was at sharp angle then we checked everything to make sure that nothing was touching that wasn't supposed to be and that all of our connections were good finally we added a male SMA connector at the bottom and we're ready to try it since 137 megahertz is close to the country he said receiver with abnormality of broadcast turned up the signal coming in strong and clear far better than any of our previous test we check the next set of satellite pastures and headed out to try again it's really important to find place that has very little radio noise we're kind of on the edge of town so we were lucky enough to find a big open field with very little noise in a previous test we were mostly looking at the NOAA satellite because even if the signal quality low we still get part of an image meteor is a digital signal and since the signal quality need to be far higher we've never attempted until now it happened to be the next satellites pass overhead so since we had our new antenna we figured we might as well try right the pass was supposed to happen started rain really hard so Artem huddled under an umbrella to keep the electronics dry while I sit out in the rain with the antenna as the satellite moves towards the laser locks the signal undergoes decision Doppler shift is the same thing to make the pitch of an ambulance change as drive 5 when it's moving towards you the pitch increases and when it moves away it decreases the same thing happens with our signal since we're trying for a digital signal we needed some tracking software to calculate this and stay on top of the signal as it moves it also gives us some information about the current elevation and direction of the satellite as the satellite rose in the sky high enough to get above an apartment building in the distance the signal started to appear we had to play with the gain a bit to boost the signal enough to pick it up properly but when everything was set right the program walked onto the signal and started downloading data the hell's as still as possible for fear of disturbing the download and by the time the satellite set we downloaded 65 megabytes of data of course this was about the time that I felt great I didn't want to get my camera wet so I don't actually have footage of that first pass but we tried it again the next morning when it was sunny and this is what you've been watching next comes the job of decoding the signal unfortunately the published data sheet by the Russian government was totally inaccurate of how to do this so we have to hunt around a little bit online eventually we found some software that could do it the first pass of the night so even though we got three channels of data two of them were completely black but in the thermal infrared channel we could clearly see clouds it it works we pulled an image directly off of the satellite when we try to gain the next morning when it was sunny we managed to get our first clear image with all three channels when we combine them we were left with a colorful image of us as the in from space we since pulled images both from meteor and NOAA satellites we made a few more refinements like wrapping the hack RF in tin foil and grounding it tacked in a Faraday cage this reduced the noise even further we've gotten so good at it we can casually do it from our front yard now and each image is more spectacular than the last in one of our meteor images we can clearly see Buenos Aires how Paulo and Rio as dark gray blobs as well as the coast of Brazil and florianópolis we can get these thermal images from meteor using one of our decoding programs and they look pretty amazing as well the NOAA images while less colorful are just as spectacular I put a link to a gallery of all of our photos in the description down below when it comes to decoding these images that'll have to be a whole separate video as there's lots of details to go over I'll go through how the decoding software works and what it's doing as well as the ins and outs of the various pieces of software this whole experiment has really been eye-opening and I've loved every second of it and now we're already working on some of our next radio experiments the satellites we've already pulled from also broadcast telemetry data which includes not only information about the spacecraft but also a ton of science data everything from the locations of anything tagged with the GPS collar or weather balloons to radiation data and more so we're already working on decoding all of that we're also looking at other satellites that broadcast at other frequencies and collect different kinds of data one of these goes 16 I saw get launched in space a few months ago while I was in Florida if we can pull from it will receive images of the entire planet and since it's in geosynchronous orbit we can pull data from it all day long finally we've also built our first radio telescope which can take images of the sky and radio frequencies we've already taken our first images and now that we know what we're doing we'll be building more in the future to look at other frequencies so keep an eye out for all of that in near future okay guys that's all I've got for this video I hope you've enjoyed if you like this video please be sure to leave a rating and if there's any other cool radio projects you think we should look into let us know in the comment section down below if you want to follow our progress on all of our projects Instagram and Facebook are the best places to do that I'm constantly posting both pictures and videos of our experiments that work - be sure to check those out also a free summary set up a patreon page so if you like what I do and feel like helping the support the continued production of videos like this feel free to check that out but by no means should you feel obligated to do so as always the videos will remain free I've also done a bit of writing and wrote a few articles which have linked in the description below that's all for now I'll see you next time

Channel: The Thought Emporium

Views: 1,140,054

Keywords: Rtl-sdr, SDR, software defined radio, satellite, space, astronomy, cross dipole, dipole, QFH, quadrifiler helix, helical antenna, antenna, sdsharp, NOAA, NOAA15, NOAA 15, NOAA 18, NOAA 19, METEOR, METEOR M2, AMIGOS, umbrella, the thought emporium, theartlav, orbides, coax, radio, orbit, orbiting, weather, photography

Id: cjClTnZ4Xh4

Length: 14min 24sec (864 seconds)

Published: Tue Mar 07 2017

Reddit Comments

[u/ChutneyRiggins]

The animation at 2:48 blew my mind. I'm starting to understand how a dipole works now.

[u/stephen_neuville]

NOAA birds are a great way to get into satellite operation. True, it's RX only, but they have orders of magnitude more transmit power than ham satellites, and most 2m satellite antennas (turnstiles, whatever) will have fine performance down on 137. And....dare I say, if SHTF, you can pull weathermaps from anywhere on Earth with a max of a few hours wait.

[u/Jonathan924]

/r/rtlsdr is a great resource for all of this. $20 dongle gets you going and receiving all of this, and those guys love NOAA stuff.

Note I didn't actually watch the video, but I can pretty much guess what's in it

[u/PKCore]

Analog does not necessarily mean just B/W images, fwiw.

[u/lol_sup]

Great video!

Satellites are also what really got me hooked on amateur radio. There's just something incredible about downloading a "live image" from space.

You should definitely go for your license so you can transmit! It's such a rush to send an APRS beacon to the ISS repeater, or talk to other hams over the voice repeater satellites.

[u/vo1pwf]

nice job....one my projects (post winter) is to get a pi with rtl-sdr to do that...

[u/SpankyMcTrolly]

Wow so cool! Thanks for sharing!