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Hillbilly Tracking of Low Earth Orbit

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    silent 30C3 preroll titles
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    applause
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    Travis Goodspeed: First I need to apologize
    for typesetting this in OpenOffice.
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    I know that the text looks
    like a ransome note.
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    But that's what happens
    when you don't use LaTex.
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    I'd also like to give a shoutout call,
    Mallnarf (?) is here, and our
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    Dinosaur rock band.
    laughs, applause
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    We are a Christian rock band - we are
    called 'Jesus lives in the ISS', and
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    we know that he's always watching us,
    but we think that it's easier for him
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    to hear our prayers when he's, you
    know, in an orbit that passes over us.
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    So we need this orbital tracking
    to know when to pray!
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    As I'm sure you can guess I'm not
    recognized as a legal minority religion
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    in Germany. I'd also like to thank Skytee
    and Fabienne (?)(?)(?) and Adami Lori
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    and Jim (?)(?)(?) for some
    prior satellite tracking work,
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    and the skuby crew (?) at Dartmouth
    College for all sorts of fun
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    whenever I bounce out there.
    This is the mission patch
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    of the Southern Appalachians Space Agency.
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    applause and cheers
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    This was drawn by Scot Biben and there are
    a few pieces of my people's native culture
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    that I need to point out here. On the
    right the little Dinosaur type thing
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    with it's finger going out, you might
    call him E.T. but we call these things
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    'buggers'. They're like this tall, and
    they're green and that's why the man
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    on the left has a shotgun.
    laughter
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    Because he doesn't want to be abducted.
    You got a satellite dish in the middle,
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    and it's sitting on sinter blocks because
    that's also a piece of my people's
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    native culture. There's a moonshine still
    in the background. That's kind of like
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    Waldcubbet (?) You make it at home, and
    from corn. And then there's the mountain...
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    A piece, it looks like there are snowpeaks
    on those mountain tops. But our mountains
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    aren't tall enough to have snow. These are
    actually that we've blown off the leads
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    in the mountains, for coal mining.
    Which is another piece of my people's
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    native culture. And at the top, in space
    you can see the ISS, and you can see
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    a banana, and you can see what I think is
    a bulb. This is to signify space trash.
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    I mean there's a lot of stuff up there.
    And, you know' it's symbolism that matters
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    in these things, you know? At BerlinSides,
    in May of 2012 I did a lecture on
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    reverse engineering the SPOT Connect. The
    SPOT Connect is a litte hockey puck type thing
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    – this is what it looks like. And these
    things are great. It weighs a bit more
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    than your cell phone, but it runs off of
    a couple of batteries, it connects
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    to your phone via Bluetooth. Originally
    these were emergency locator beacons.
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    So if you're going hiking...
    Have any of you seen the movie where
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    the guy has to cut off his arm with a dull
    knife? If you're hiking and you don't want
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    allow you to tweet, and make Facebook posts.
    laughs, laughter
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    the same experience, you buy one of these
    things. And then there's an emergency button
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    you can push, that transmits your GPS
    coordinates via satellite to rescue workers.
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    But that was boring, so they had to add
    social media. laughs, laughter
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    So in addition to keeping you from chewing
    off your own arm this device will also
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    The idea is as you're running – here I'm
    crossing the Schuylkill River in Philadelphia
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    and the Android phone on the left is
    making a post. And I did an article
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    on reverse-engineering the Bluetooth
    side of these things. Because... I use
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    a weird brand of phone that Microsoft
    killed off, and I'm terribly bitter about it.
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    But I also figured out the physical layer.
    And that's what this diagram shows.
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    This transmits 1.6125 GHz. And it
    sends a pseudo-random stream, so
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    each one of these zeros is a long chunk
    where it's bouncing back and forth
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    between 2 different frequencies And
    the same for the ones. But the way
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    that the pattern works is that it switches
    the signal whenever it is going from
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    the 0 signal to the 1 signal. And
    internally, there are these little pops
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    that you can actually identify on
    a Software Defined Radio recording.
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    And this is how you can reverse-engineer
    the signal that the SPOT Connect is
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    sending up to its satellite network.
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    Everything is clear text on this.
    And it's completely unencrypted.
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    It just has your serial number, your GPS
    coordinates, and a bit of ASCII text.
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    If you listen on this frequency and you
    have the correct recording software
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    you can actually watch all of the SPOT
    Connect messages that are transmitting up
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    from your location. And this would be
    great except that this is designed for
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    hiking in areas where there's no cell
    phone service. So having an antenna
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    on the uplink frequency is kind of
    useless. You know you would actually
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    have to go out to a national park, find
    some guy who is about to chew his arm off,
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    and then you could listen to his uplink
    where he is like tweeting: "Hey I'm gonna
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    chew my arm off", you know?
    laughter
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    So that's great as a proof of concept,
    but it's not really anything practical.
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    The current state of that was that I knew
    the protocol and I could sniff the uplinks.
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    But I wanted to sniff the downlinks. So
    it's easy for me to get the thing that
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    goes up to the satellite. But what I wanted
    was what comes down from the satellite.
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    And that requires a satellite dish. But
    a geo-stationary dish isn't good enough
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    because the satellites that run this
    network – there are a lot of them,
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    it's called the Globalstar network.
    They fly really low across the earth,
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    and they fly across the earth in very
    tight, very fast orbits. So they move
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    from horizon to horizon in 15 to 20
    minutes. Which means that you either need
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    like a sweat shop army of kids trying to
    aim the satellite dish as it's going across.
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    Or you need to make
    it computer-controlled.
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    Stepping back from the SPOT Connect for
    a little bit, and discussing some prior research.
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    Adam Laurie did some work with
    geostationary satellites. These are
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    the satellites that stay in one position
    in the sky. He gave 2 sets of talks
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    – one in 2008 and the second in 2010.
    And he used a DVB-S card connected
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    to a satellite dish with a diseqc motor,
    so that it could move the satellite dish
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    left and right, in order to scan a region
    of the horizon. His tool is publicly
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    available, it's called satmap. You
    can grab it at this URL. And then
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    after he finds a signal, he has a feed
    scanner. Normally when you use
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    Satellite TV you provider gives you
    a listing of the frequencies, and
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    your provider gives you an exact orbital
    position to aim your satellite dish at.
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    But Adam's tool allows you to scan to see
    which frequencies are in use, and which
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    protocols are in use, once you've correctly
    aimed your dish. And he also describes
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    a technique for moving your dish left and
    right while doing this in order to identify
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    where the satellites are. This recording
    here is from a re-implementation
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    that I made of Adam's work, in order to
    catch up with it. In this diagram the x-axis
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    shows the azimuth, that shows how far left
    or right my satellite dish has moved.
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    And then the y-axis shows the frequency.
    And all of these dots are strong signals.
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    So every vertical bar in which you see
    chunks of frequencies, that's a satellite.
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    But these stay in the same position. So
    it's easy for me to repeat this experiment.
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    It's easy for me to re-run it, and to find
    the same satellites in the same position.
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    It's easy to debug this. But it can't move
    in elevation. This diagram is actually
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    a very small slice of the sky. We're
    looking at a single line, maybe
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    10 degrees across. Maybe only 5 degrees
    across. So hacking Ku-band
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    – the television satellites – has the
    advantage that you can use cheap
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    standardized hardware. I bought one of
    these DVB-S cards in Mauerpark, in Berlin
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    for 3 Euro. You can use standardized
    disecq motors, you can buy them at
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    a satellite TV shop. TV signals come with
    video feeds, so you can actually see
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    pictures. There was a scandal ca.
    4..5 years ago, where they were finding
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    drone [control] feeds that were being
    bounced across these satellites.
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    In the nineties it was very popular to
    listen to the sort of unedited sections
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    of interviews, when people would be
    interviewed over a satellite, before
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    Skype and such things became options.
    And there are also networking signals here
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    using TCP/IP packets. So you can actually
    turn your DVB-S card into promiscuous
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    ethernet adapter, and start sniffing
    all of the traffic that comes across.
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    This is also a great way to get free
    downlink bandwidth. Because you can just
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    flood packets at an address that, you know,
    will be routed to you, or several addresses,
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    and then you sniff it out as the legitimate
    receiver ignores them. But it also has
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    some disadvantages. It only works with
    geostationary satellites. If the satellite
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    is not staying in the same position
    relative to the ground then you can't
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    track it. Your dish also moves very
    slowly. And it only moves left and right.
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    It won't move up and down. And you're
    limited to standardized signals.
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    While it's great that you get video and
    TCP/IP you're never going to get anything
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    weird. You're not gonna get any mobile
    data, you're not going to get any
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    Brazilian truck-drivers – we will get to
    those in a bit. laughs
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    I misspoke, you actually will get Brazilian
    truck-drivers in this. So I bought
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    a satellite dish. One of the best things
    about living in America is that you can
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    buy industrial hardware cheap as dirt
    on ebay. I know things aren't likely
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    used to being a cat XXXX by human children
    anymore. But this satellite dish here
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    on the left – the one in the radome –
    that's my dish. And to the right,
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    that's the boat that it came from.
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    applause
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    This came from a military ship.
    But the dish itself is also available
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    for civilian use on very large yachts. The
    dish itself is a Felcom 81 and it was
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    intended for use with a network called
    Inmarsat. Imarsat allows for
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    telephone connections, and also data
    connections when you're on a boat.
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    So if the crew wants to call home
    or wants to go to AOL Keywords
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    or whatever was popular back when
    this was common they could do that.
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    And the dish was desgined to sit
    at the very top of a ships' mast.
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    The reason why is that at the top of
    the mast there aren't any obstructions
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    – it has a clear view of the sky in all
    directions. But there's a complication
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    with being on the top of the mast. Which
    is that the ship is rocking beneath you
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    and you're moving more than the rest the
    ship. So they have stepper motors for
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    azimuth, elevation and tilt. And then
    they have spinning gyroscopes.
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    Back before the iPhone there was this dark,
    dark time when gyroscopes actually spun.
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    And this is the sort of gyroscope that
    it has. It actually has 4 of them so
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    that it can measure its movement. And then
    it has a control computer. So the idea is
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    that the dish itself can be moved while
    remaining absolutely stable with regard to
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    the gyroscopes. So it compensates for
    the rocking of the ship beneath it as it's
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    targeting a stationary satellite.
    In America this costs 250 Dollars, but
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    it's electronics equipment. So while you
    think that would only be a 180 Euro
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    it's more like 2500. And that's before
    import duties and it being impounded.
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    We also have this lovely culture in which
    people love excuses to use their trucks.
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    So the guy that I bought this from offered
    to deliver it to my home from the 200 dollars.
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    It was an 11 hour drive. But if you wanted
    this you'd have to bring it back in your
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    carry-on luggage, and it could be awkward.
    I got this dish and I decided I had to do
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    something with it. So I created the
    Southern Appalachians Space Agency.
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    I'm from the state of Tennessee, formerly
    known as the State of Franklin until
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    North Carolina invaded us. It's ok,
    I know Europeans suck at history.
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    laughs
    laughter
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    Now I'm trying to think of how to show
    you on a map where Tennessee is
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    without having a map but, you know, it's
    okay I know you suck at geography and
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    we forget (?)
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    From audience: It's very
    near Texas, to the north.
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    Travis: Texas is our first colony. But
    it's actually a decent drive to the east.
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    Due east (?). You don't
    actually have to go anyways.
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    So what I did was I took these motors
    which were designed to be able to move
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    the satellite dish to compensate
    for the rocking the ship and
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    I re-purposed them to track through
    the sky while the ground is stable.
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    We don't have very many earthquakes in
    Tennessee. The last one that we had
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    made rivers run the wrong direction. But
    it's okay – it's a geography thing. So
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    this allows me to track things that
    are moving through the sky. But it
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    doesn't actually matter where they're
    moving in the sky because that's
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    just a software problem. So in addition to
    tracking objects that are in low-earth orbit
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    by a software patch I can also track things
    that are in deep space. It's not much harder
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    to track deep space probes or stars than
    it is to track items in low-earth orbit.
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    And then I added a software defined radio
    which allows me to record a signal now
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    and demodulate it later. Which is necessary
    if you intend to reverse-engineer a signal.
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    Because a lot of the downlinks from these
    satellites are completely non... completely
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    undocumented. And being able to tune in to
    the right frequency is only half of it.
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    You also need a recording of sufficient
    quality that you can reverse-engineer
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    after the fact. We are sort of spoiled by
    software defined radios. When doing
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    software defined radio work we usually
    have a very good signal to work from.
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    So having high quality signals for later
    reverse-engineering is necessary.
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    I really wanted to be able to identify
    undocumented downlinks for low-earth orbit
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    in the same way that we already do this
    for geo-stationary orbit, using tools
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    like the ones that Adam Loria and Jin XXX
    made. So I built a software framework
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    as a collection of Python daemons. And
    these run across a home area network
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    in my house. There's a Beaglebone inside
    of the Radome. And an x86 server
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    in the house. Or AMD64, whatever the kids
    call it these days. And then I used Postgres
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    for coordination. So that all of these
    daemons can talk to each other without...
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    without me really caring which machine
    they're on. So for maintenance I can have
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    my laptop pretending to be the dish,
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    and can have stepper motors on my desk,
    and I can watch them spin, and I can even
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    make a model of the dish and swap these
    components in and out without the rest of
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    the network being confused. This also
    allows for sequal (?) injec... attacks to
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    physically move my dish. Which is why the
    Sassin (?) network is not on one of those
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    fancy WEB 2.0 things. Because of you could
    inject, say, update targets at Namical's (?)
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    Voyager 1. Then my dish would physically
    move and start tracking Voyager 1
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    through the sky. Voyager 2 doesn't
    actually come into the sky because of
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    my position in the Northern hemisphere.
    So, it's okay, I know you suck at geography.
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    But Voyager 1 is going up, and Voyager 2
    is going down. There's a Realtek
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    Software Defined Radio for the radio
    reception. Although these things
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    are garbage. So I'm in the process of
    replacing this for the HackRF. There's
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    also an EiBot board for motor control.
    We'll get back to that in a minute.
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    And there's an Inertial Measurement Unit
    from Vectornerve (?) which actually measures
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    using the fancy MEMS gyroscopes and
    a MEMS compass how I'm moving.
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    This isn't accurate enough to target the
    dish, so instill (?) the counting steps
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    to move the dish. But it is accurate
    enough to tell me when my belts
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    have broken. Or when I'm up
    against the physical obstruction.
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    This is skytee helping me out with the
    dish. He's zip-tying it. Because, you know
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    we know everything about duct tape where
    I come from, but we know nothing
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    about zip ties. So I had to bring in
    a German engineer.
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    laughter
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    We call him a Gerry wigger (?) but, you know...
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    This is the satellite dish itself. And you
    can sort of see in this photograph
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    where we've strapped on the equipment.
    There's like an embillica (?) cord. Or more
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    like a spinal column that actually runs up
    the back of the dish. So we just added
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    new cables onto that line. And then
    zip-tied them in place. And skytee came up
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    with all these crazy ideas like that
    we should use chains and zip-ties
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    to make sure that the cables don't tear
    themselves out. And that worked
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    tremendoudly well in practice. So, as this
    thing spins around by the original design
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    there's a ring connector that all of the
    signals go through. That all of the
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    networking goes through. That all of the
    rest goes through. And that worked
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    in the nineties because it had no reason
    to send anything faster than 9600 baud.
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    But with the modern signals going across
    it - I need 100MBit/s or even GB ethernet.
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    That's not enough. I need more than
    2 wires. So there's a cable that comes
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    across it, and then I rely on the
    software to keep it from wrapping
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    that cable around itself. So it can only
    move, say, 400 degrees around.
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    But that's still more than a full circle.
    So by stopping halfway and moving back
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    I can prevent it from getting stacked (?).
    We've got the Beaglebone on the left,
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    in the middle there's a USB hub, and
    on the right is the motor controller.
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    The Beaglebone runs Debian Linux. And
    takes care of sending the software defined
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    radio recordings over the network. It also
    takes care of updating the motor positions
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    to be the ones that the database declares
    should be current. The stepper motors
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    themselves are the originals that the dish
    was designed with. And they're running
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    to an EiBot Board. The EiBot board was
    intended for plotting on Easter eggs
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    laughs
    I feel, you know... is that neat?
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    laughs
    applause
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    So you can actually aim a satellite dish
    that's as tall as you are, with of these
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    fancy motors using less sophisticated
    equipment than what's used
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    in a 3D printer. Don't panic, though.
    It's a hell of a lot more reliable
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    than a 3D printer. But we needed
    some sort of backup. In addition
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    to the inertial measurement unit telling
    us when the device had snagged itself.
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    It would also help to have a visual
    queue. Because the satellite dish
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    sits in Tennessee, and while I love my
    home town, and, you know I'm very
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    proud of being Tennesseean it's also
    a long way to travel when you need
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    to re-orient the dish. Using an
    accelerometer it's easy enough
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    to correct the elevation. Because you can
    use the accelerometer as a level, and
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    you can use that to tell how high up the
    dish is pointing, at an absolute scale.
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    But the compass isn't very accurate. So
    instead, as a backup we have a webcam
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    that's taped to the top. Taping
    is my people's native culture.
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    We have it taped to the top, and then
    it's pointing backwards. So this gives us
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    like a rear view camera, from the
    dish's position. So as the dish sits
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    inside of its radome... - junk cars in the XXX
    are also my people's native tradition!
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    So the dish sits there next to my
    brother's Toyota Supra. And that thing,
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    you know, that thing flies as soon as it
    gets an engine put back in it. So it is -
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    sits there and it's moving. But externally
    you can't see where it is. Which means
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    that I can't call my family in Tennessee
    and blackmail them into - yet again -
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    looking at my dish to tell where it's
    pointed. There are bolts that hold this
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    down. It takes half an hour to remove the
    lid, another half an hour to put it back on.
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    So instead we took the radome...
    that's Frank, he's my cat.
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    Give a "Cheers!" for Frank!
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    applause and cheers
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    Yeah, we had such a great time with Frank.
    And we never knew that she was pregnant.
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    If you happen to need kittens and wanna
    pay the custom's fees I'll hook you up!
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    So then we took tape and ran tape down the
    edges of the radome, and then marked it.
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    So from the markings you can tell
    which clock position the back
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    of the satellite dish is pointing at. So
    if you point the dish towards 12:00
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    you know that you're roughly at 6:00,
    so you know that it's pointing South.
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    And then you can sort of scan the sky
    for a stationary target, and navigate
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    off of that, to recover your position.
    Software-wise... Remember,
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    the whole thing runs through Postgres,
    so I just tunnel the Postgres over SSH,
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    and then I wrote a Python client that
    displays the satellite positions and
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    the satellite state in PiGame (?). This is
    intended for making those games (?)
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    really see the rabbit. And the rabbit
    jumps on the other rabbit. But it... works!
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    And it works perfectly well enough
    to target the dish. Because all that
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    this software has to do is plot the
    positions of the satellites, and
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    give orders back to the database when
    I click on a satellite, or click on a position.
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    It can also display stars. So the red
    items are satellites which are not selected.
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    The green item is Ghost3 (?) which is
    the satellite that I'm targeting. And then
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    the white items are stars in the sky. Now
    this is a plot in which the azimuth is
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    on the X axis, and the elevation is on the
    Y axis. But I can also arrange it into
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    a polar plot. Which sort of gives me an
    upside-down view of the satellite dish
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    looking at the sky. I doubt you can read
    it, but just above the green circle
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    in the center, that's Polaris which is the
    North star. It's also weird because,
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    you know, working on this, you know,
    I thought that I got really good at astronomy
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    until I realized that I only knew what the
    stars looked like during the day.
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    laughter
    laughs
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    And it being PiGame (?) you can actually
    run it on a mobile device. So the same client
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    that runs on my laptop can also run
    on my Nokia N900. laughs
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    applause
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    A significant portion of the GUI client for
    this was written while stuck on the U-Bahn,
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    connected over 3G, SSH through, and just
    using emacs on the phone. laughter
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    laughs
    applause
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    If you're one of those people who needs to
    complain about the N900 being too old,
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    it also runs on the N9. And then,
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    you can take the data out of this, and run it through scientific software. In addition of the software defined radio recordings themselves being dumped out to a text file or a binary file on disk you can also dump out things like the received signal strength indicators (RSSI). So this is a screenshot in which I'm identifying different satellites that I've seen in the sky. Based upon their downlink signal peaks. You can see the noise floor there, at the bottom, and then there's a rather strong signal on the left. And a weaker neverware (?) signal on the right.
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    The daemons that build this up... you need an orbit prediction daemon.
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    Because you need to know where the satellites are, and where they're going, and where they will be by the time you get to them. You need to update the orbits themselves.
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    LEO satellites are described in TLE files. These are called 'Two Line Entry'. And they're called Two Line Entry because they're three lines long. laughter
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    But this format isn't incredibly accurate for satellites that correct their orbit. So you need a daemon that grounds the new files from spacetrack and this is just a matter of a recursive
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    you also need motor control because you need to move the dish physically to
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    and then you need radio daemons to
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    and then after that you start to take software recorderings of that
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    So for orbit prediction i began with a DOS program that had been ported to Unix called predict. This works but it's garbage. It only supports 20 stars
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    because it's designed for astronomy photographers that want to take pictures of things
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    because otherwise you have to set an alarm clock for the half-hour pass where you can record them.
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    So i managed to track every single item in geostat orbit this thick ring here is the clarke-bell of all geostationary satellites as viewed from my northern hemisphere [?]
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    All IPC is running through this PostreSQL
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    you then send it simple commands, like SM,3000,500,-400
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    And then it will count that out, and send me back an OK. If i want to disable the motors, i'll send them em,0,0
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    EM,1,1 will enable both motors in 1/16s
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    You can see the motors themselves with the belts and the geartrains. This thing on the right would probably be illegal for me to turn on
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    The belts and stuff need to be measured to figure out what the reduction is
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    the IMU unit , this vectornav vn100 is a
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    it costs 500$ which was more than all of the other components together.
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    Now for position calculation, the elevation itself comes from the IMU. The azimuth
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    so the accelerometer will drift while the compass will be confused by the magnetic fields while the
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    and the IMU will be come of a backup how to make it reliable, but at the moment the position
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    The radio daomens. The first is a spectrum analyzer. It just measures the strength of the frequency
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    the downlink recorder dumps the IQ values
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    directly to an NFS share.
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    Client GUI is PyGame
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    Also notes these faint blue lines are positions where i saw particularly strong signals
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    I'm running out of time by these markers. Does this mean we skip Q&A or that I get kicked off of stage?
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    It takes SDR, it can provide maps of used different satellites in the sky.
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    I'd also like to make other ground stations. The software that I wrote should be portable
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    Another way that you can do it, the way that it's traditionally done to track stationary satellites is with a YAGI antenna
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    This is my van, my van is amazing. applause
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    Thanks to nick farr. I had a bit to much too drink in
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    But you want a news-van. And I said Hell yes, I want a news van!
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    But most importantly, it does SECAM
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    This is the control panel,
    and that's my talk!
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    applause
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    Herald: Thank you so much. There
    actually is time for Q&A now.
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    Travis: Well, first I'd like to introduce
    you to my cat. If we could go back
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    to the prior image. This is Frank! We
    didn't know it at that time, but
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    Frank was not dead when this picture was
    taken. If you'd like kittens get in touch.
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    Okay. Are there any questions?
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    Question: Great talk. What's the most
    interesting signal you decoded so far?
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    Travis: At the moment I'm sort of stuck
    at the L band range. Because of filters
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    that I have yet to remove. So everything
    gets attenuated, and becomes annoyingly
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    quiet outside of the 1.5..1.6 -ish range.
    The Globalstar network is what I'm most
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    interested in targeting next. I cam't wait
    to see what people are tweeting
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    while they should be enjoying nature.
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    Herald: Is there a question
    from the internet?
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    Signal Angel: Yeah, the internet has
    many questions. So first one was:
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    Is there really no authentication or
    encryption on the Q band IP services?
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    So you can just spoof at will? And can the
    birds see the physical leakage and of
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    the source accurately enough to find who
    is spoofing?
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    Travis: I'm not an expert in Ku band. The...
    for the downlink the bird has no clue
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    as to the location of the dish. Because
    you're only listening. They can roughly
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    figure out your geographic area because...
    they need to figure out where
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    the spot beam is going. So they might know
    whether you're in, say, Germany or
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    in France. But they won't know whether
    you're in Heidelberg or Mannheim.
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    They do have forms of authentication for
    many satellite networks. Satellite TV
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    is one of the best-protected network
    services. Because of the satellite wars
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    in the 90's. In which TV pirates would
    fight back and forth with smart card
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    designers. But there are also many
    unencrypted links. And there are...
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    because of standard protocols those
    are particularly easy to find in Ku band.
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    Question: You've been talking about
    using RTLSDR from osmocom.
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    And you were talking about your spectrum
    analysis program. Is this one working
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    with RTLSDR?
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    Travis: So... RTLSDR... so I'm using
    the RTLSDR not the osmo-sdr.
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    Which are separate. The spectrum
    analyzer is working with the RTLSDR.
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    My complaint about the RTLSDR is that
    when you have a strong signal next to
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    a weak signal the weak signal is
    utterly useless for interpretation.
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    Question: Okay. Thank you.
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    Herald: Another question
    from the internet?
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    Signal Angel: Okay, next question from the
    internet is: how do you record the radio signal
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    from the dish, at what sampling rate?
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    Travis: The RTLSDR samples at 2 million
    samples per second. As soon as I switch it
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    over to the HackRF, well, we're having
    20 million samples per second.
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    The sampling rate can be reduced once
    the bandwidth of the signal is known.
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    For radio (?) storage. And the recordings
    can also be compressed.
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    But it's still a hell of a lot of storage.
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    Herald: Any other questions?
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    Signal Angel: The internet
    has more questions...
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    Herald: Okay...
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    Signal Angel: Did you look into obtaining
    a capacity of IBAN with copper (?), as used
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    for the rotary gentries in CT scanners?
    Those can apparently transmit contactless
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    several GBytes per
    second, bi-directionally.
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    Travis: I've not looked into those.
    It seemed better to have an Umbellaco (?)
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    cable and to be careful not to snap it.
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    The whole thing was done for a budget
    of less than 2000 Dollars, and can be
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    recreated for less than a budget of 1000
    [Dollars]. And they... so we tried to avoid
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    fancy parts. The local radio shack loved
    us because we'd swing in and buy all sorts
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    of crazy stuff. As soon as we told them
    that we wanted the satellite dish to
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    dance Gangnam style...
    laughs
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    laughter
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    Thank you Carnaugh(?)
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    applause
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    silent postroll titles
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    subtitles created by c3subtitles.de
    in the year 2017. Join, and help us!
Title:
Hillbilly Tracking of Low Earth Orbit
Video Language:
English
Duration:
47:03
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