Speaker 1: Welcome to Tech Stuff, a production from I Heart Radio.
Speaker 1: Hey there, and welcome to tech Stuff. I'm your host,
Speaker 1: Jonathan Strickland. I'm an executive producer with I Heart Radio
Speaker 1: and I love all things tech And recently Amazon canceled
Speaker 1: their television series truth Seekers, which I thought of as
Speaker 1: sort of a cross between Shaun of the Dead and
Speaker 1: The X Files. So in the series, a cable technician
Speaker 1: named Gus played by Nick Frost, is obsessed with ghost
Speaker 1: hunting and he gradually indoctrinates his new partner, who says
Speaker 1: his name is Elton John. He's played by Sampson Keo. Anyway,
Speaker 1: it's it's a cute show. It's a little odd in tone.
Speaker 1: And the part that really applies to this episode, however,
Speaker 1: is that one of the things that Gus fixates on
Speaker 1: in the early episodes is a radio frequency playing a
Speaker 1: numbers station. It's based off of an actual historical number
Speaker 1: station that folks call the Lincolnshire Poacher. And here's what
Speaker 1: it sounds like, gree nine seven one five green nine
Speaker 1: seven one hive green nine seven one hive. So that's
Speaker 1: a real thing, or it was a real thing, and
Speaker 1: it's not the only such station out there. There have
Speaker 1: been lots of numbers stations over the years, some using
Speaker 1: different jingles to signal an incoming series of numbers. Some
Speaker 1: of them have male voices, some use female voices, some
Speaker 1: use children's voices. Some of them are in morse code,
Speaker 1: some have people reciting not just numbers but letters and
Speaker 1: code signals. A lot of them are super creepy, which
Speaker 1: makes them really ideal for a show about paranormal investigation.
Speaker 1: But while the supernatural stuff is fanciful nonsense, the numbers
Speaker 1: stations are actually anchored in our real world. And while
Speaker 1: tech Stuff did do an episode about numbers stations many
Speaker 1: many years ago, I thought it would be good to
Speaker 1: use numbers stations as a way to talk about not
Speaker 1: just what they are, but also about short wave radio communications,
Speaker 1: the physics of radio in general, and the process of
Speaker 1: ciphering and encrypting information. So this is really gonna be
Speaker 1: a big overview, catch all kind of podcast. So let's
Speaker 1: start off with radio itself. Radio wave are part of
Speaker 1: the electromagnetic spectrum. Uh. They are there along with stuff
Speaker 1: like microwaves, visible light, X rays, and gamma rays. All
Speaker 1: of this is part of one big spectrum of electromagnetic radiation.
Speaker 1: You could actually think of it all as different flavors
Speaker 1: of light if you like. It's just that the slice
Speaker 1: of light that we can see is a very small
Speaker 1: slice of the overall spectrum. Now, specifically, radio waves are
Speaker 1: in the long wavelength part of that spectrum. Electromagnetic radiation
Speaker 1: moves in waves all at the speed of light, because hey,
Speaker 1: really it is just light, just different flavors of it.
Speaker 1: But those flavors of light do have different wavelengths, which
Speaker 1: also means they have different frequencies. So what does that
Speaker 1: mean exactly, Well, let's start with wavelengths. Imagine a nice
Speaker 1: smooth wavy line the distance between two consecutive crests on
Speaker 1: that wave, so the very peaks at the top parts
Speaker 1: of our curve. In other words, that would be one
Speaker 1: wave length from one crest to the next. A frequency
Speaker 1: just refers to the number of times a given cycle
Speaker 1: happens within a given amount of time, and we frequently
Speaker 1: use one second as the time unit, and with electromagnetic radiation,
Speaker 1: we talked about how many full wavelengths of a given
Speaker 1: signal pass a specific point in space within one second.
Speaker 1: We also use the unit hurts to describe this relationship.
Speaker 1: A one Hurts frequency would have one cycle or one
Speaker 1: wavelength per second passing you know this given point in
Speaker 1: one second, a giga Hurts frequency has a billion cycles
Speaker 1: per second. Now, all electromagnetic radiation is traveling at the
Speaker 1: same speed, which is around three thousand kilometers per second
Speaker 1: in a vacuum. Because the speed actually changes depending upon
Speaker 1: the medium through which the radiation is traveling, that happens
Speaker 1: to be the speed limit of the universe. Nothing goes
Speaker 1: faster than that, So the energy is traveling at that speed,
Speaker 1: but the frequency is dependent not just on speed but
Speaker 1: how long those waves are. In fact, because we know
Speaker 1: all these waves are traveling at that same speed, we
Speaker 1: can figure out the wavelength if we know the frequency,
Speaker 1: and vice versa. So the formula is wavelength equals the
Speaker 1: speed of light divided by the waves frequency. Alternatively, frequency
Speaker 1: is equal to the speed of light divided by the wavelength.
Speaker 1: So as long as we know either the frequency or
Speaker 1: the wavelength, we can figure out the other one. Because
Speaker 1: the speed of light is a constant, it's not a variable.
Speaker 1: On the longest wavelength side of the spectrum are radio waves,
Speaker 1: which can measure more and a hundred meters in length,
Speaker 1: so a radio wave with a wavelength of one meters
Speaker 1: would have a frequency of about three mega hurts, meaning
Speaker 1: about three million wavelengths would pass a given point in
Speaker 1: a second, and each wavelength is measuring one hundred meters
Speaker 1: between those crests. Again, the speed of the signal is
Speaker 1: still the speed of light. But let's say we get
Speaker 1: to the other end of the spectrum, towards the very
Speaker 1: very very tiny wavelengths on the electro magnetic spectrum. And
Speaker 1: when I say tiny, I mean really tiny. Gamma radiation,
Speaker 1: which represents the smallest of the waves that we know about,
Speaker 1: are less than one hundred pico meters in length, and
Speaker 1: a pico meter is one trillionth of a meter, so
Speaker 1: this is actually smaller than the nanoscale. The frequency started
Speaker 1: out at around ten to the power of nineteen hurts
Speaker 1: or ten quintillion hurts. Now, I've talked about electro magnetic
Speaker 1: radiation in terms of waves, but we also know that
Speaker 1: it behaves as both a wave and a particle. There
Speaker 1: are a lot of experiments that have shown this, and
Speaker 1: they're fascinating. But I don't want to get too far
Speaker 1: off track. Some of you out there might be screaming
Speaker 1: too late now, so we should also mention photons, the
Speaker 1: particles of light. A photons energy is directly proportional to
Speaker 1: the electromagnetic frequency of that wave. It's also inversely proportional
Speaker 1: to the wave length, So gamma rays pack a huge
Speaker 1: energetic wallop, while radio waves, by comparison, are whims. So
Speaker 1: let's get back to the radio spectrum. In particular. We
Speaker 1: know that radio waves have the longest wavelengths in the
Speaker 1: electromagnetic spectrum, which means they also have the lowest frequencies
Speaker 1: and the lowest amount of photonic energy. Generally speaking, we
Speaker 1: group electromagnetic frequencies ranging from thirty hurts or thirty wavelengths
Speaker 1: per second up to three hundred giga hurts or three
Speaker 1: hundred billion wavelengths per second. Obviously this is a really
Speaker 1: big range, but all of that are radio frequencies. Now,
Speaker 1: different countries divvy up this spectrum of frequencies for different uses,
Speaker 1: some of which depend upon the capabilities of those frequencies. So,
Speaker 1: for example, if you're looking at around thirty hurts, this
Speaker 1: is the extremely low frequency or e l F ELF range.
Speaker 1: You know, I used to play in ELF range in
Speaker 1: Dungeons and Dragons. Wait don't think of something else. So
Speaker 1: these wavelengths are really long and they are good at
Speaker 1: penetrating stuff like deep water, so it can be used
Speaker 1: for very basic communications with submarines. A M radio would
Speaker 1: be up in the medium frequency range for radio frequencies,
Speaker 1: and also the medium wavelength range. Just above that are
Speaker 1: the high frequency short wave radio hands, which are what
Speaker 1: we're really going to talk about a lot today. These
Speaker 1: have a wavelength between ten and one and frequencies that
Speaker 1: are between three and thirty mega hurts. Radio waves in
Speaker 1: this band of frequencies have some really useful properties, and
Speaker 1: one of those is the broadcast range, as in how
Speaker 1: far these radio waves can travel. So higher frequency radio
Speaker 1: bands can essentially only travel by line of sight, so
Speaker 1: there is a limited range to them. If you've ever
Speaker 1: listened to an FM radio station, because FM frequencies are
Speaker 1: in a band called very high frequency or VHF, then
Speaker 1: you might have had the experience of the station starting
Speaker 1: to give out as you travel away from the source.
Speaker 1: Depending upon the power of the broadcasting station, you typically
Speaker 1: have a range of around thirty to forty miles or
Speaker 1: fifty to sixty kilometers, but radio waves that are a
Speaker 1: bit longer can travel further thanks to a layer in
Speaker 1: Earth's atmosphere called the ionosphere. Higher frequencies can move right
Speaker 1: through the ionosphere. They just punch right through and go
Speaker 1: out into space, but lower frequencies, those having the longer wavelengths,
Speaker 1: aren't able to do that, so they actually bounce off
Speaker 1: the layer and come back down to Earth. By reflecting
Speaker 1: back down to Earth, these radio waves could travel much
Speaker 1: further than they would just by line of sight. Now,
Speaker 1: as the name suggests, the ionosphere is a layer of
Speaker 1: our atmosphere that is host to ionized particles. Ionization is
Speaker 1: the process by which an atom becomes charged either with
Speaker 1: a positive charge meaning it has lost electrons electrons are
Speaker 1: the negatively charged particles. So then you've got an imbalance.
Speaker 1: You have more protons with the atom than you have electrons,
Speaker 1: and thus you have an overall positive charge, or it
Speaker 1: could become negatively charged, meaning that an atom has taken
Speaker 1: on more electrons. Now, this makes that layer of Earth's
Speaker 1: atmosphere a electrically conductive. It happens because our atmosphere is
Speaker 1: hit by ultra violet light from the Sun and it
Speaker 1: hits the atoms in this layer of the atmosphere it
Speaker 1: energizes those atoms, and when the atoms get really energetic,
Speaker 1: the electrons move further out from the nucleus and they
Speaker 1: can actually peel off if they have enough energy. Now
Speaker 1: you've got free electrons, and those free electrons are either
Speaker 1: reflecting radio waves if they have a long enough wavelength,
Speaker 1: or they can actually absorb them or otherwise allow them
Speaker 1: to pass through for shorter wavelengths. This works in both directions.
Speaker 1: By the way, not just radio waves coming from Earth,
Speaker 1: but also radio waves that are coming in from space,
Speaker 1: because lots of stuff out there generates radio waves. I'm
Speaker 1: not talking about aliens. I'm talking about like solar activity
Speaker 1: and stuff like that. Now, the activity of the ionosphere
Speaker 1: changes throughout a day over any given spot on Earth.
Speaker 1: So during the daytime, that part of the Earth is
Speaker 1: facing the Sun, so the atmosphere overhead is being hit
Speaker 1: with a lot more ultra violet radiation, and thus the
Speaker 1: lower part of the ionosphere, the part that's closer to us,
Speaker 1: ends up getting more crowded with ions. Now that means
Speaker 1: that longer radio waves are going to hit the ionosphere
Speaker 1: at a lower altitude and then reflect off. But at nighttime,
Speaker 1: the sun is on the other side of the planet.
Speaker 1: So the lower part of the ionosphere kind of calms
Speaker 1: down a bit, and now the longer radio waves will
Speaker 1: actually travel at a further altitude. They'll go higher up
Speaker 1: before they hit the ionosphere and reflect back down. That
Speaker 1: also means that you can actually pick up longer wavelength
Speaker 1: radio signals from further away at nighttime because there's this
Speaker 1: different angle that allows the waves to reflect and travel
Speaker 1: even further. Now, the history of radio, as in the
Speaker 1: technology that we use to leverage radio waves, this gets
Speaker 1: complicated because we call the technology this same terms as
Speaker 1: we call the the scientific phenomena that is interoperating with
Speaker 1: the technology. But we'll we'll carry on. So the tech
Speaker 1: radio has a very long and complicated history, and it's
Speaker 1: full of some really serious drama. I mean not just
Speaker 1: radio dramas like soap oparas, I mean like drama drama.
Speaker 1: Just get a couple of radio enthusiasts talking about Tesla
Speaker 1: and Marconi or Armstrong and DeForest and see how things
Speaker 1: go if you want some entertainment. But we'll just cut
Speaker 1: to the chase and say that by World War One,
Speaker 1: people were figuring out potential uses for radio waves like
Speaker 1: being able to send communications quickly across large areas if
Speaker 1: you know you're trying to coordinate numerous groups of soldiers
Speaker 1: in different theaters of combat. For example, communicating by radio
Speaker 1: involves generating a carrier wave signal at a specific frequency
Speaker 1: and then modulating it so, in other word, changing that
Speaker 1: signal in some way in order for it to carry information.
Speaker 1: A steady signal gives you no real useful information other
Speaker 1: than someone or something is generating this signal. But by
Speaker 1: creating a way to encode and decode information by altering
Speaker 1: that signal, do you have a way to send more
Speaker 1: complex information. A M radio modulates a carrier signal by
Speaker 1: changing the amplitude of the wavelength, and this requires a
Speaker 1: good deal of power, and the long wavelengths mean you
Speaker 1: need big radio towers to beam out these signals. FM
Speaker 1: radio modulates signals through frequency modulation, altering the frequency of
Speaker 1: the signal slightly. And radio stations, like the kind we
Speaker 1: tune into for entertainment purposes, these are fixed frequencies right
Speaker 1: like If they weren't, you would never be able to
Speaker 1: tune into your favorite radio station because you wouldn't know
Speaker 1: what frequency to go to. So this means they can't
Speaker 1: take advantage of the changes in the ionosphere. They're always
Speaker 1: stuck transmitting at a set frequency, whether conditions are good
Speaker 1: for long range transmission or not. Shortwave radio operators have
Speaker 1: a little more flexibility. They're working with a specific series
Speaker 1: of frequencies in the high frequency range of the RF spectrum,
Speaker 1: but they can swap from one of those sets of
Speaker 1: frequencies to another and thus take advantage of atmospheric conditions.
Speaker 1: So early in the day you might use one set
Speaker 1: of frequencies that are available to you, and late at
Speaker 1: night you might use a different set, because the actual
Speaker 1: radio waves will travel at different distances as the day changes.
Speaker 1: But there's another aspect to communicating during wartime, which is
Speaker 1: that generally speaking, you don't want the people who are
Speaker 1: fighting on the other side of the war to know
Speaker 1: what the heck you're talking about, so you have to
Speaker 1: come up with some means of of you skating the
Speaker 1: meaning of your message. This is particularly important with radio
Speaker 1: for a very obvious reason. See, there are a lot
Speaker 1: of different ways to send secret messages, and some of
Speaker 1: them are more secure than others. If you and I
Speaker 1: are the only ones who know about a black glassy rock,
Speaker 1: near a trina field, you know, a rock that has
Speaker 1: no business being there, And I hide a message under
Speaker 1: that rock for you, there's a decent chance that you'll
Speaker 1: get to the message before anyone else does. I might
Speaker 1: not even need to encode the message at all, because
Speaker 1: no one else even knows that there's a rock there.
Speaker 1: If I were to send you a message through the mail, well,
Speaker 1: now there's a few points where someone could intercept that message, right,
Speaker 1: I mean, perhaps the batties check my mailbox. They see
Speaker 1: that I've put the little mail flag up, so they
Speaker 1: come and check it and they steal the message before
Speaker 1: I can even go anywhere. Or maybe they keep checking
Speaker 1: your mailbox on the other side, looking at incoming mail,
Speaker 1: and they grab my message when it arrives at your mailbox.
Speaker 1: Or maybe they're super tricksy and they've infiltrated the postal
Speaker 1: service and Cliff the mailman is secretly a dirty old
Speaker 1: spy always suspected it. Well. Radio communications are out in
Speaker 1: the open. Anyone with a receiver that has an antenna
Speaker 1: that can tune into whichever frequency is being used can
Speaker 1: actually listen in on that frequency, So you have no
Speaker 1: control over who can hear what you're sending out. So
Speaker 1: if you're sending something out in secret, you have to
Speaker 1: encode it in some way that makes it hard or
Speaker 1: impossible to determine what is being communicated. Now, when we
Speaker 1: come back, will talk about how this sometimes involves making
Speaker 1: creepy radio broadcasts. But first, let's take a quick break.
Speaker 1: Let's say you want to create your own radio station.
Speaker 1: You've put up a transmission tower, you figured out your
Speaker 1: power needs to generate the signal necessary to claim a
Speaker 1: subsection the r F spectrum set aside for broadcasts, and
Speaker 1: you're ready to go right. Well, no, now if you
Speaker 1: don't want to get shut down and find or worse.
Speaker 1: In order to make sure the spectrum isn't just a
Speaker 1: free for all, which would make communication difficult at least,
Speaker 1: governments have designated specific bands of frequencies for specific uses.
Speaker 1: See if multiple transmitters were trying to use the exact
Speaker 1: same frequency, everything would get garbled. You would have tons
Speaker 1: of interference. If you've ever used a pair of walkie talkies,
Speaker 1: you probably know that it's standard for folks to say
Speaker 1: over when they're done talking, because the walkie talkies switched
Speaker 1: between transmitter and receiver mode and without the over you
Speaker 1: might have both parties trying to talk at the same time,
Speaker 1: and no one can hear anything because you're both holding
Speaker 1: down the transmit button. Well, when you think about all
Speaker 1: the radio, television, cellular, WiFi, and other signals zooming around
Speaker 1: out there, all of which are part of the RF spectrum,
Speaker 1: you quickly realize that you've got to make up some
Speaker 1: rules or else no one would ever know who they're
Speaker 1: talking to. Now, way back in eighteen sixty five, the
Speaker 1: International Telegraph Union came into formation, and in nineteen thirty
Speaker 1: four it changed its name to the International Telecommunication Union,
Speaker 1: and it's part of the United Nations today, and one
Speaker 1: of its jobs is to designate specific slices of the
Speaker 1: RF spectrum for specific uses to allow for seamless operations
Speaker 1: between the world. That way, the radio is made by
Speaker 1: a company in Japan will work in places like the
Speaker 1: US because the frequencies that we've set aside for terrestrial
Speaker 1: radio stations are the same, assuming that both US and
Speaker 1: Japan are following the suggestions from the i t U. Now,
Speaker 1: it's up to the governments of various countries to enforce
Speaker 1: these rules. In the United States, radio stations have to
Speaker 1: obtain a license from the Federal Communications Commission to get
Speaker 1: a permission to broadcast on specific frequencies within the A,
Speaker 1: M or FM bands of the RF spectrum. There are
Speaker 1: other frequencies reserved for amateur radio operators, but if you
Speaker 1: want to operate your own amateur station, you have to
Speaker 1: get a license from the f c C, and passing
Speaker 1: a test is part of that process. Now, if you
Speaker 1: just want to listen to radio, that's different. You don't
Speaker 1: need a license. In that case, you could have a
Speaker 1: short wave radio set and as long as you're not transmitting,
Speaker 1: you're just listening, no licenses needed. But to transmit, you
Speaker 1: gotta get permission first, and the f c C will
Speaker 1: even assign a call signed to you. Number stations are different.
Speaker 1: With commercial radio stations, you can do some research to
Speaker 1: see who owns and operates that station, but with numbers stations,
Speaker 1: there's a distinct lack of information. This puts them in
Speaker 1: the realm of pirate radio stations. These are stations that
Speaker 1: have no identifying information associated with them and they are
Speaker 1: operating without being registered with the FCC or similar agency
Speaker 1: in other countries. Now that doesn't mean that these agencies
Speaker 1: like the f c C don't know about them. There
Speaker 1: is a look the other way situation in which one
Speaker 1: part of the government is using stuff that the other
Speaker 1: parts just don't need to worry about. You know, by
Speaker 1: the way, if you're wondering if people operate pirate radio stations,
Speaker 1: they sometimes do. But there are ways to triangulate signals
Speaker 1: and determine where those signals are coming from. So if
Speaker 1: someone is broadcasting without permission on a specific frequency, it's
Speaker 1: typically just a matter of time before the Feds come
Speaker 1: in and shut things down. Now, you could hop onto
Speaker 1: other frequencies, but unless your audience knows where to tune in,
Speaker 1: you would likely be talking to no one or at
Speaker 1: least very few people. So, since we know that it's
Speaker 1: possible to figure out where a radio signal ridge and eates,
Speaker 1: and since numbers stations can remain in operation for years
Speaker 1: or decades, we have to draw the conclusion that these
Speaker 1: numbers stations have some sort of sanction from governments, otherwise
Speaker 1: they would get shut down. Now, some sources say that
Speaker 1: numbers stations, these radio frequencies that are sending out seemingly
Speaker 1: nonsensical information, got their start in World War One. Others
Speaker 1: say it was actually closer to World War Two, and
Speaker 1: I tend to suspect that the latter is more accurate.
Speaker 1: Radio was important in World War One, but it was
Speaker 1: also still pretty early on in the evolution of the technology.
Speaker 1: But at some time around World War One and World
Speaker 1: War Two, someone got an idea, and that idea was
Speaker 1: to establish a transmission on a particular signal or sometimes
Speaker 1: a series of signals that would change throughout the day
Speaker 1: to take advantage of the ionosphere and the differences and
Speaker 1: signal propagation, and the signal would broadcast encoded and for
Speaker 1: vation presumably two spies. So let's say you're running a
Speaker 1: top secret spy organization like the m I six. Now, granted,
Speaker 1: you're spending a lot of time dealing with the fact
Speaker 1: that your top spy has a habit of introducing himself
Speaker 1: to any one in hearing range and then drinking his
Speaker 1: way across the world. But you've got a lot of
Speaker 1: other more responsible spy types out there too, and you
Speaker 1: might occasionally need to send them orders. But if your
Speaker 1: operative is halfway across the world, deep in enemy territory
Speaker 1: and you can't rely on normal communication channels, you might
Speaker 1: want to send a coded message by shortwave radio. This
Speaker 1: has a huge advantage and that the radio signal goes
Speaker 1: out everywhere, so you know that your enemies will be
Speaker 1: able to detect the signal, but they won't know what
Speaker 1: the message was or who it was actually for. If
Speaker 1: you were to call your operative, it's possible someone could
Speaker 1: detect the call and trace it to the recipient the spy,
Speaker 1: and thus compromising them. So sending out a message via
Speaker 1: radio means you give no information about who is supposed
Speaker 1: to receive that message. The operative nose to tune into
Speaker 1: a specific radio frequency at a specific time. This is
Speaker 1: something that you have to work out beforehand, obviously, as
Speaker 1: most of us aren't aware of what's going on with
Speaker 1: radio waves all around us, or we'd have a lot
Speaker 1: of trouble concentrating on anything. You might set up a
Speaker 1: regular broadcast session using different frequencies throughout the day, depending
Speaker 1: upon whichever one works best. And maybe some days you
Speaker 1: have nothing to report, so you might even send out
Speaker 1: a code for that, or it might just be gibberish.
Speaker 1: But other days you need to alert your operative to
Speaker 1: return home, or step it up and place a bigger
Speaker 1: bet in baccarat or whatever it may be. So these numbers.
Speaker 1: Stations typically have some sort of indicator at the top
Speaker 1: of the hour. The Lincoln Share Poacher, which we played
Speaker 1: at the beginning of this episode, is an example of that.
Speaker 1: That little tune marked the beginning of a transmission, followed
Speaker 1: by the actual message. The message would be a sequence
Speaker 1: of some sort, typically numbers, sometimes letters. The voice might
Speaker 1: be a recording, or it might be read live on
Speaker 1: the air. It could be a man, a woman, or
Speaker 1: a child's voice. You might pick up a short wave
Speaker 1: signal with someone counting in another language. But what do
Speaker 1: those codes actually mean? Well, that's the real question, and
Speaker 1: that's one that's kind of impossible for us to answer
Speaker 1: because the coded messages use an approach that is unbreakable
Speaker 1: assuming you don't get hold of the secret. So this
Speaker 1: leads us to a discussion about cryptography. Cryptography, or the
Speaker 1: art of writing and or breaking codes, is ancient, and
Speaker 1: people have come up with a lot of interesting ways
Speaker 1: to hide important information even if it's in plain sight,
Speaker 1: and have it be indecipherable as it were to the
Speaker 1: uninitiated at least. These range from the very simple strategies
Speaker 1: such as a rudimentary replacement cipher like the Caesar cipher,
Speaker 1: where you just substitute symbols for letters or just shift
Speaker 1: letters around. So for example, you might say a B
Speaker 1: actually means C and a C means D. That's a
Speaker 1: very simple Caesar cipher. While these sort of ciphers might
Speaker 1: confound someone at casual first glance, they aren't particularly hard
Speaker 1: to crack. If you happen to know what language was
Speaker 1: used to write the message, you can look for patterns
Speaker 1: in those symbols to indicate common letter combinations. So, for example,
Speaker 1: in English, the letters J, Q, X, and Z are
Speaker 1: really pretty rare, but the letters A, E, O, and
Speaker 1: T are really common. So you can look for symbols
Speaker 1: that show up a lot and start to think, well,
Speaker 1: these most likely represent some of the most common letters.
Speaker 1: And then you have letter pairs. In English, you get
Speaker 1: stuff like T H E are oh N and A
Speaker 1: N a lot. You can also look for common double
Speaker 1: letters like T, T, S, S, E and so on.
Speaker 1: Knowing the rules of the language means you can start
Speaker 1: looking for clues as to what these symbols actually represent.
Speaker 1: Some ciphers take one little extra step, including some symbols
Speaker 1: for common letter pairings. Really, this is just taking a
Speaker 1: page from other alphabets, including older English alphabets. So for example,
Speaker 1: the old English letter thorn represents the th h or
Speaker 1: the sound. So maybe you have symbols that can represent
Speaker 1: certain letter pairs or double letters or phonetic sounds, and
Speaker 1: that can make it a tiny bit more challenging if
Speaker 1: someone wants to break the code. Now, there are also
Speaker 1: ciphers that use clever means to change how letters are
Speaker 1: encoded in some predetermined way, which is what the famed
Speaker 1: Enigma machine could do. The Enigma machine was like a
Speaker 1: really complicated typewriter, only when you hit a given letter
Speaker 1: such as W on the machine, the machine would generate
Speaker 1: a different letter based on whatever its initial settings were.
Speaker 1: So let's say you hit W and you get G
Speaker 1: instead you write that down for your encoded message. Then
Speaker 1: the Enigma machine would advance its mechanism so that the
Speaker 1: entire encoding process changed. So if you hit W again,
Speaker 1: now the machine wouldn't produce G for the second W,
Speaker 1: it would produce something else, like maybe P. The Enigma
Speaker 1: machine was so complicated that it prompted Allied forces in
Speaker 1: World War Two to construct early computer systems, and had
Speaker 1: it not been for a couple of quirks with the machine. So,
Speaker 1: for example, the machine would never use the correct letter
Speaker 1: as a cipher for itself. Well, if it hadn't been
Speaker 1: doing those sort of things, the Allies might not have
Speaker 1: ever cracked at code. And there are other methods to
Speaker 1: send information in a clandestine way. There's hiding information within
Speaker 1: some other message or inside a physical object. This is
Speaker 1: called steganography. So you can imagine a painting that has
Speaker 1: a hidden message incorporated in it, so that anyone who's
Speaker 1: just looking at the painting just see's a painting, but
Speaker 1: someone who knows what to look for can read the message.
Speaker 1: Steganography is fascinating stuff, and in our modern tech age,
Speaker 1: it can extend to stuff like files that are hidden
Speaker 1: within other files. So how do numbers stations keep information secret?
Speaker 1: What's through one of the oldest tricks in the book
Speaker 1: the one time pad. Using a one time pad properly
Speaker 1: is pretty much a guarantee that no one will ever
Speaker 1: be able to crack the code. It's a perfect cipher
Speaker 1: in that regard, though in other ways it has its
Speaker 1: own drawbacks. Now, when we come back, we'll talk about
Speaker 1: the one time pad. Some of the famous number stations
Speaker 1: out there and speculate on what it all means. Spies.
Speaker 1: It means spies. We'll be right back, okay. So the
Speaker 1: beauty of the one time pad is that if you
Speaker 1: do it correctly, it is unbreakable. The reason for that
Speaker 1: is twofold. One is that the key that you used
Speaker 1: to actually encrypt the message is a randomly generated key,
Speaker 1: So each letter of your message has an encryption method
Speaker 1: that is independent of every other letter in your message,
Speaker 1: so somewhat intercepting the message won't be able to look
Speaker 1: for those patterns in the symbols. And the other reason
Speaker 1: is that you use each randomly generated encryption key only once.
Speaker 1: After you use it, you destroy the key. Since you
Speaker 1: don't repeat the process, you avoid giving codebreakers enough information
Speaker 1: in order to crack a message. If the code never repeats,
Speaker 1: you can't establish any patterns. Now, the downside of this
Speaker 1: is that you do have to make sure that everyone
Speaker 1: you're communicating with has a copy of the encryption keys.
Speaker 1: So whenever you generate that random key, you have to
Speaker 1: make sure the person or people that you're sending messages
Speaker 1: to have exact copies that they are able to keep safe.
Speaker 1: Going back to the Enigma machine, if the Germans had
Speaker 1: followed the procedure of changing the machine settings for every
Speaker 1: single message, it would have made the code even more
Speaker 1: difficult to crack. But an actual practice, doing this was
Speaker 1: very hard to keep straight and could result in miscommunication.
Speaker 1: So for the sake of convenience and clarity, the Germans
Speaker 1: often wouldn't change the settings as frequently as they were
Speaker 1: supposed to, and that gave the allies a foothold and
Speaker 1: figuring out what was actually going on. Generating a coded
Speaker 1: mess it requires a few steps, and since we're talking
Speaker 1: about numbers stations, I'll go with numbers first. But keep
Speaker 1: in mind, it's not just the way numbers work, it's
Speaker 1: just it's the easiest way to explain it to you guys.
Speaker 1: So your first step is that you create a simple
Speaker 1: substitution cipher for all the letters in the alphabet, plus
Speaker 1: any symbols that you plan on using, for example, any punctuation.
Speaker 1: You assign numbers to each of those letters and symbols,
Speaker 1: so you could go just as simple as numbering the
Speaker 1: English alphabet from one to twenty six A to Z,
Speaker 1: but that's pretty simplistic. So you establish your basic cipher
Speaker 1: and you make sure everyone who needs it has that
Speaker 1: they know that if they see a one, that means
Speaker 1: a two means to be for ciphered text. But that's
Speaker 1: just one step. Next, you generate your encryption key. Now,
Speaker 1: this should be a string of random numbers, with each
Speaker 1: number ranging from zero to nine. Typically you group them
Speaker 1: in blocks to make it easier to transmit and receive.
Speaker 1: The most common one I've come across is blocks of
Speaker 1: five digits each. Now this is really important. Your encryption
Speaker 1: key has to be as long or longer than whatever
Speaker 1: message you intend to send. So if your message is
Speaker 1: one forty characters long, you need one hundred forty randomly
Speaker 1: generated numbers, and you create a whole bunch of these
Speaker 1: for the purposes of communication, with each encryption key taking
Speaker 1: up a single page out of a pad of paper.
Speaker 1: If you were to look at one of these sheets
Speaker 1: of paper, all you would see are a bunch of
Speaker 1: digits divide up into groups of five, and just no
Speaker 1: apparent pattern to them because they would be randomly generated.
Speaker 1: So when it comes time to encode a message, let's
Speaker 1: say your message is extra act asset. That's what you
Speaker 1: want to tell your operative. You would write down your
Speaker 1: message in English, So you write down extract have a
Speaker 1: space asset, and then you would use your cipher method
Speaker 1: to change each letter into its corresponding number. So we'll
Speaker 1: go with the very simple substitution of A is one,
Speaker 1: B as two, and so on, but we would probably
Speaker 1: use something different in the field. We're gonna use zero
Speaker 1: as an empty space. A lot of real number stations
Speaker 1: use a different method, uh in order to make it
Speaker 1: easier for people who are receiving the messages to actually
Speaker 1: decode them. But you get where I'm going. So using
Speaker 1: our substitution cipher, we see that the first letter of
Speaker 1: our message, the E in extract, would be the fifth
Speaker 1: letter the alphabet, So our first ciphered note is five.
Speaker 1: The second letter of extract is X. That's the twenty
Speaker 1: four letter, So then we have to write two four,
Speaker 1: So this actually takes up two digits in our our
Speaker 1: ciphered text. When we're done, are simple substitution cipher would
Speaker 1: look like this. This is extract asset. If we were
Speaker 1: to write it all out by numbers, it would be
Speaker 1: five two four to zero, one eight one three two
Speaker 1: zero zero, one one nine one nine five to zero.
Speaker 1: But this is not encrypted yet. It's just enciphered which
Speaker 1: means that if someone were to intercept this message, they
Speaker 1: could potentially suss out what it means pretty quickly. I mean,
Speaker 1: for one thing, if you listen to that, even though
Speaker 1: it's broken up into two different blocks of of digits,
Speaker 1: you do have a repeating one nine one nine in
Speaker 1: there that could indicate a double letter, and in this
Speaker 1: case it actually does. Those are the who say is
Speaker 1: an asset. So now you have to encrypt this message.
Speaker 1: This is when we take one of those randomly generated
Speaker 1: encryption keys, the ones that are at least as long,
Speaker 1: but preferably longer than the messages we plan to send,
Speaker 1: and we've grouped the encryption key into blocks of five digits,
Speaker 1: but again these digits are each randomly generated. We grab
Speaker 1: the first key off our pad. Let's say that this
Speaker 1: key starts with a five digit block that says zero
Speaker 1: eight to three nine. Now we would probably just hold
Speaker 1: onto those first five numbers, not use them for encryption,
Speaker 1: because those first five numbers will alert our agents in
Speaker 1: the field which of the encryption keys they need to use,
Speaker 1: because remember they have a whole pad of these things,
Speaker 1: and each one is different, so they have to look
Speaker 1: in their pad and say all right, Well, let's look
Speaker 1: for the encryption key that starts with zero eight to
Speaker 1: three nine. That's our starting point. So we've got our
Speaker 1: ciphered text and beneath those numbers of the ciphers, so
Speaker 1: our first block was five to four to zero. Beneath
Speaker 1: that we would write the second block of the encryption key,
Speaker 1: and then we would do the third block of the
Speaker 1: encryption key, then the fourth block, and then the fifth
Speaker 1: block to correspond with the four blocks of five numbers
Speaker 1: that represent extract asset. Now again these are randomly generated
Speaker 1: digits from zero to nine. Then we do quick subtraction
Speaker 1: digit by digit. We take the encryption key number for
Speaker 1: each corresponding digit of our ciphered text, and we subtract
Speaker 1: the encryption key from the ciphered key. So I remember
Speaker 1: our first five numbers of our cipher text are five
Speaker 1: to four to zero. Let's say that our randomly generated
Speaker 1: encryption key is two seven. Well, if we're subtracting digit
Speaker 1: by digit, that means our first pairing would be the
Speaker 1: five from our block of cipher text and the two
Speaker 1: from the encryption key. So five minus two gives us three.
Speaker 1: This is the beginning of our encrypted text. But our
Speaker 1: second subtraction is seven that's from our encryption key, from
Speaker 1: two that's from our cipher. In this case, you would
Speaker 1: make the two a twelve for the purposes of subtraction,
Speaker 1: and your answer would be five and so on. So
Speaker 1: you subtract each encryption key digit from the ciphered message
Speaker 1: digit to create the encrypted message. So our first block
Speaker 1: of encrypted five digits would be three five three three five.
Speaker 1: Remember we started with five to four zero. That in
Speaker 1: turn stands for the letters e x T. Anyway, you
Speaker 1: do this encryption method for your entire message, You turn
Speaker 1: it into blocks of numbers that you can broadcast those
Speaker 1: blocks of numbers through a numbers station. The agent tunes
Speaker 1: into that specific frequency and an agreed upon time. They
Speaker 1: listen for that first block of five numbers, they grab
Speaker 1: the sheet out of their pad that corresponds to that,
Speaker 1: they write down the message that's being broadcast, number and
Speaker 1: by number. They match each new number to the next
Speaker 1: digit in the encryption key, and then they just add
Speaker 1: those two numbers together to get the ciphered version of
Speaker 1: the message. Then they convert the ciphered version to the
Speaker 1: original message, so they're just reversing the process. It's pretty elegant,
Speaker 1: and because that encryption key is random, it is impossible
Speaker 1: to crack. This is also why if you listen to
Speaker 1: a numbers station broadcast, the speaker typically will repeat a
Speaker 1: block of five numbers a couple of times, maybe several times,
Speaker 1: before moving on to the next block of five numbers.
Speaker 1: This gives the listener enough time to make sure they
Speaker 1: are transcribing each digit correct really, otherwise their decryption process
Speaker 1: isn't going to work. Now, this key is impossible to
Speaker 1: crack as long as that encryption key remains random, but
Speaker 1: generating random numbers is actually trickier than it sounds now.
Speaker 1: One way to do this would just be to take
Speaker 1: a tin sided die and roll it a bunch, and
Speaker 1: then write down each of the results of your roles
Speaker 1: as you go. The number of times you roll the
Speaker 1: die depends on how long you're encryption key is going
Speaker 1: to be, but keep in mind you want that encryption
Speaker 1: key to be at least as long as the messages
Speaker 1: you're planning to send preferably longer. So if your key
Speaker 1: has twenty blocks of five digits each, you would be
Speaker 1: rolling that die one times and writing down the results
Speaker 1: and the first five digits of your new key typically
Speaker 1: aren't used as encryption but rather identification. You can use
Speaker 1: other means to identify which pad or which page and
Speaker 1: a pad you should be using, but that's a pretty
Speaker 1: common one. There are computer programs that are supposed to
Speaker 1: generate random numbers. You know, you've probably heard of r
Speaker 1: n g s or random number generators, but what these
Speaker 1: really do is that they generate pseudo random numbers. They're
Speaker 1: not true random numbers. Computers have to follow rules. Now,
Speaker 1: those rules can be really complicated, but they're still rules,
Speaker 1: and randomness sort of falls outside of the rules category.
Speaker 1: So computer random number generators typically aren't truly random. Now
Speaker 1: to mere mortals, it can seem random, but in most cases,
Speaker 1: a person who knew the rules that the program was
Speaker 1: following in order to generate the numbers could create another
Speaker 1: program to duplicate that result, and that means the numbers
Speaker 1: aren't really random at all, and that could put an
Speaker 1: encryption key at risk. For that reason, a lot of
Speaker 1: spy agencies don't rely on computers to generate random numbers.
Speaker 1: Typically they'll use other methods. Numbers station is really proliferated
Speaker 1: in the years after World War Two and throughout the
Speaker 1: Cold War, presumably because you had spies all over the
Speaker 1: ding dang during place with American spies in Russia, you
Speaker 1: had Soviet spies in America, and so on. The Numbers
Speaker 1: stations declined in well number over the years, but there
Speaker 1: are still a few out there broadcasting digits to whomever
Speaker 1: is listening. Some of them may still be connected to espionage,
Speaker 1: but others might be connected to non governmental activities, you know,
Speaker 1: like drugs smuggling. Some of the Numbers stations are shall
Speaker 1: we say, executed in a less than professional manner, which
Speaker 1: suggests that they are not backed by, you know, state
Speaker 1: backed operations. It's also possible that some numbers stations are
Speaker 1: broadcasting out meaningless numbers just to obvious skate what's really
Speaker 1: going on. If you flood the airwaves with nonsense, you
Speaker 1: keep your opponents guessing at what you're actually up to. Now,
Speaker 1: I've already played for you a bill of the Lincolnshire
Speaker 1: Poacher Numbers Station, which may have well been connected to
Speaker 1: the Secret Intelligence Service of the UK. But there was
Speaker 1: also the Swedish rhapsody, which would begin with a jangly
Speaker 1: little tune that sounds like it came straight from an
Speaker 1: ice cream truck. There was the Gong, which began with
Speaker 1: a series of low pitched percussive tones as if bells
Speaker 1: or gongs were being struck, followed by someone reading out
Speaker 1: numbers in German. There were tons of others, and there's
Speaker 1: still several in operation today. A Keen Fernandez, a short
Speaker 1: wave radio enthusiasts, became fascinated with these numbers stations and
Speaker 1: released a set of CDs containing recordings of various numbers
Speaker 1: stations from around the world. You can find the recordings
Speaker 1: available online for free, and lots of musicians have actually
Speaker 1: incorporated parts of those recordings into their own works. One
Speaker 1: of the brilliant things about number stations is that, well
Speaker 1: you might figure out where the broadcast is coming from
Speaker 1: if you have the equipment to triangulate a signal. Like
Speaker 1: I said before, you have no way of knowing who
Speaker 1: those messages are intended for. Their just broadcast out into
Speaker 1: the world, so anyone could be the intended recipient. But
Speaker 1: there have been a few cases in which authorities caught
Speaker 1: spies and uncovered their involvement with numbers stations, but not
Speaker 1: because they had some magical way of finding out who
Speaker 1: was getting the messages. So, for example, in two thousand one,
Speaker 1: U S authorities arrested Anna Mantz. Mantz had secured a
Speaker 1: position with the US Defense Intelligence Agency, which, y'all, that's
Speaker 1: impressive for a spy to infiltrate an organization that you know,
Speaker 1: spies on people, wowsers. And actually that happens, not like
Speaker 1: super frequently, but way more frequently than I would have thought.
Speaker 1: I mean, I figured, if you're the experts on spying,
Speaker 1: you should be pretty good at picking out ones that
Speaker 1: are trying to infiltrate your organization. But as the Mission
Speaker 1: Impossible movies tell us, that's not always the case. Anyway,
Speaker 1: the authorities suspected her of act ding on behalf of
Speaker 1: another country. They searched her home and they found a
Speaker 1: code sheet for encrypting messages, plus a short wave radio.
Speaker 1: It turned out she was spying for Cuba, and in
Speaker 1: eleven German authorities arrested a married couple named Hydron and
Speaker 1: Andreas Schlug, both of whom were spying for the Russians
Speaker 1: and had been for years before the Berlin Wall had
Speaker 1: come down. During the raid on the couple's home, Hydron
Speaker 1: was actually in the middle of receiving a short wave
Speaker 1: transmission in the United States. In the mid nineties, the
Speaker 1: FBI identified possible Cuban spies in the United States and
Speaker 1: they managed to break into the home of one of
Speaker 1: those spies. They found a computer there with a decryption
Speaker 1: program on it. Essentially, it was a computer with the
Speaker 1: one time use pad programmed into it, so it had
Speaker 1: the codes used by Numbers stations, and the FEDS just
Speaker 1: copied the key and they used it to decipher incoming messages.
Speaker 1: That allowed them to build a big legal case against
Speaker 1: numerous spies. But again, if done correctly, this approach is unassailable.
Speaker 1: It just requires that the spies remain, you know, undetected
Speaker 1: through other means, and that they keep a tight grip
Speaker 1: on their decryption keys. Otherwise the jig is up. And
Speaker 1: while the number of stations continue to be creepy and
Speaker 1: a suitable fit for films and TV series about paranormal
Speaker 1: stuff or aliens or whatever, the truth of the matter
Speaker 1: is that they're probably telling operatives overseas to knock it
Speaker 1: off with all the martinis and extract assets stuff like that.
Speaker 1: Fascinating things. By the way, you can find lots of
Speaker 1: recordings of Numbers stations online. You can also find websites
Speaker 1: that allow you to use a software that lets you
Speaker 1: tune into different shortwave radio frequencies around the world, which
Speaker 1: is really really cool that it lets you actually listen
Speaker 1: in two different shortwave broadcasts, which may or may not
Speaker 1: be number stations. I mean, there are a lot of
Speaker 1: people using shortwave radio to just chat with each other
Speaker 1: like amateur radio operators, but occasionally you can actually find
Speaker 1: operating numbers stations. There are lots of resources online if
Speaker 1: you are interested in looking into that. You can also
Speaker 1: always invest in short wave radio equipment, although that kind
Speaker 1: of depends on where you are, like it may not
Speaker 1: you may not be able to pick up really interesting
Speaker 1: broadcasts depending on your location. You also typically have to
Speaker 1: use really super long antenna that need to be you know,
Speaker 1: elevated a pretty good distance to pick up broadcasts from
Speaker 1: really far away, so your mileage may vary with physical
Speaker 1: shortwave radio setups. But as I say, there are websites
Speaker 1: where you can tune into someone else's shortwave radio and
Speaker 1: use special software that lets you tune into different frequencies,
Speaker 1: being able to to really listen in on whatever is
Speaker 1: going on that's being picked up by that particular radio set,
Speaker 1: So if you are interested, make sure you do some
Speaker 1: more research and check it out. Very cool stuff. Alright.
Speaker 1: That wraps up this episode of tech Stuff. In our
Speaker 1: next episode, who knows what I'll talk about. I don't,
Speaker 1: but I'm looking forward to it. If you guys have
Speaker 1: suggestions for topics I should cover in future episodes, let
Speaker 1: me know. It could be a technology, a trend in
Speaker 1: tech company, a person, really, anything that's related to tech.
Speaker 1: I'm eager to look at, examine, and then report back
Speaker 1: to you guys. But let me know on Twitter the
Speaker 1: handle there is tech Stuff hs W and I'll talk
Speaker 1: to you again really soon. Text Stuff is an I
Speaker 1: Heart Radio production. For more podcasts from my Heart Radio,
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