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Encryption Security

Spooks in the Wire 74

Salon is running a cool article about numbers stations - shortwave radio stations that broadcast encrypted messages to spies worldwide. I hadn't known about this, though it makes sense if you think about it - the U.S. government uses a similar scheme to communicate with nuclear subs at sea. The article includes links to a site which has .mp3 recordings of some of the transmissions. Spooky. They've even transcribed some messages for a possible crack attempt, though if the men in black are truly using one-time pads this seems (ahem) unlikely to succeed.

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Spooks in the Wire

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  • This stuff was also well known after WW2. There's numbers station in Jean Cocteau's "Orphee".
  • How does one go about becoming a spy? :) I wanna get secret shortwave transmissions.
  • I don't see getting the one-time pad to your operatives as difficult at all, given that you have some technology available to you. The one-time pad can be reduced to the size of a period in a letter and read by the operative with a microscope (of course, this means the operative must be in a place where he can access a microscope). The guy living next door to you who is secretly a covert op receives his one-time pad in his mail every day and nobody is the wiser because nobody else knows that the letter contains a one-time pad. The OTP could be the period at the end of the first sentence, for example, in a seemingly mundane letter from the op's grandmother or something. I read in an old crypto book several years back that the best codes are the ones that don't appear to be codes at all.

    Furthermore, imagine that someone *did* intercept the one-time pad. He still doesn't necessarily know what broadcast it applies to. For example, the op could just know that letters from grandma apply to broadcasts on thursday at 3pm, letters from cousin Phil apply to thursday at 11pm, and so on. The spooks could engineer the whole thing to be so incredibly complex that it would not only be completely impossible to crack, but completely impossible to attempt a crack at all -- and yet still very easy for the op to commit the rules to memory.
  • Am I the only one who noticed that they have a few transmissions online and are selling the rest on CDs? Between Salon and Slashdot, they're going to make a killing...I wonder where all this money is going...
  • What is a good shortwave radio for a newbie (such as myself :-) ?
  • Well, it's a good way to communicate. Not even the OTP, but posts to usenet.

    If you want to send a message to a spy somewhere with internet access you could just post the message to alt.test, or some other group where it wouldn't get cancelled as spam or offtopic. Then the spy DLs it and runs it through PGP...

    It would be a lot less suspicious for a tech-stealing spy working at a megacorp that builds warplane for the government to be seen spending time on the computer reading usenet news than listening to a shortwave radio, jotting down numbers.

    The messages would be easily filterable by the bad guys if they clued in, but there are many ways you could sneak something like this past them...

    As was mentioned, on-topic posts on a botany list containing a hidden code. Depending on the length of the code message, this sort of thing could be done without changing the message much.

    Smart cards with a serial port could revolutionize OTP systems. Simply burn a few hundred 1k blocks of OTP onto the card, then as each is used, it self destructs... Smart cards are already being built that do this if tampered with. The spy simply sends the message to the pad and enters a PIN, the card checks the next block to see if the code will decrypt the first two bytes of known plaintext (not a problem because it's not a cipher, knowing part of it doesn't help to know the rest) and if so, decrypts, sends the message back, and triggers some self destruct that burns out the rom in that block.

    With this, spies could have what looks to be a regular telephone smartcard (in the EU at least) and might even function as one, but when used in a different way, laid on a reader (which would be fairly easy to build, needing only 3-4 wires) and sent an activation code (that the spy would memorize) they would start to function as OTP code units until unplugged, when they were revert to being phone cards. And perhaps, to help the spy, they could even be unlimited phone cards. :)
  • . Triangulating a station
    which is several thousands of miles away needs
    pretty large legs on the triangle.


    Or a super-exact ex-NASA protractor...



  • Triangulating a station
    which is several thousands of miles away needs
    pretty large legs on the triangle.


    Or a super-exact ex-NASA protractor...



  • by Goody ( 23843 )
    ... .--. --- --- -.- ... .. -. - .... . .-- .. .-. . ..--..

    ... .... --- ..- .-.. -.. -... . .-- .. .-. . .-.. . ... ... .-.-.-

  • by Anonymous Coward
    .... . .... . .-.-.- - .-. .. -.-. -.- -.-- .-.-.- .-.-.- ...- . .-. -.-- / - .-. .. -.-. -.- -.-- .-.-.- .--. . --- .--. .-.. . / .--. .-. --- -... .- -... .-.. -.-- / - .... .. -. -.- / .-- . .----. .-. . / - .-. --- .-.. .-.. ... .-.-.-
  • I wonder how many people got the pun...

  • Anyone have linkage to materials on shortwave for beginners? This article made me rather interested. Not just in the numberstations, but some of the links had recordings from other cool things. I might just have to build me a little radio, if I knew how.
  • Interesting. I didn't know Rugby was in the VLF band. That's probably more efficient for you Brits, considering you're an island and can radiate directly off the continental shelf. Mostly we Yanks use the ELF grid out of northern Michigan, which radiates right thru the Earth. Using a half-click or so of wire for the antenna, you could easily build an ELF receiver, although the FCC, the NSA and the Navy might get kind of interested in why you were bothering.

    For you uninitiated Linuxheads, the stuff we're talking here has incredible penetration power -- basically, anywhere subs are likely to operate -- but horrible bandwidth. A xmission for a very simple code meaning "USS So-and-so, hit your next window for satcom message to follow" can take on the order of minutes for a few bytes.

    Read The Hunt for Red October, which is a bit dated and necessarily kinda squirrely on details but gives you a general sense of how the procedure works.

    (Geez, this thread is starting to read like something outta sci.military.naval.)

  • More quasi- sci.military.naval stuff, eh?

    Navy RM's are no longer taught Morse as of (I believe) a year ago, and there are damn few left in the fleet who can use Morse. There's a small but vocal contingent of old-timers out there who suggest that losing a low-tech skill like Morse could put us at a disadvantage in a crunch -- like an InfoWar scenario where EMP and HERF are employed to knock back more sophisticated communications techniques.

  • Ah. I think that's madness. Sadly, I have some
    first-hand experience with it :(
  • For a general beginning guide to shortwave, along with receiver reviews, links and frequencies, I'd recommend Radio Netherland's Media Network pages. You can start at: http://www.rnw.nl/realradio/index.html From there, it's nicely laid out for beginners and experienced listeners alike.
  • The most famous of which is the Venona traffic in which case Russian spy traffic was encrypted using a one time pad. *But* the Ruskies lost part of a copy of that pad in Finland and the Finns gave us a copy. God bless the Finns. That OTP key was used to decrypt Rusky spook traffic here.

    After the Russians opened their archives, scholars started reading Venona traffic from *that* end and someone got around to asking, "Why does NSA still have all this stuff classified?" So the Venona decrypts were released. It turns out that the Rosenbergs weren't exactly the innocent victims of red-baiting that the Lefty press claimed for decades.
  • by RallyDriver ( 49641 ) on Wednesday September 15, 1999 @04:46PM (#1679388) Homepage
    Since WW2 it has been standard practice for field operatives sending and receiving traffic over totally insecure channels in this manner to use one time pads.

    In the days of pencil and paper, a one-time pad was easier to apply (usually simple addition) than an algorithmic cypher, and of course infinitely more secure. I can't see that the computer era would do anything but facilitate it.

    Nuclear submarines at sea still receive VLF carrier modulated (morse code style) transmissions for low volume traffic as they are one of the few things that penetrate easily to patrol depths. The Royal Navy still uses Rugby WT for this purpose, and I know there is a US equivalent.

  • by Anonymous Coward
    To communicate with subs deep in the water they use a transmitter that actually transmits its signal straight into the ground at such low frequencies that it can reach subs deep under water. Unfortunately it is also very slow (less than 1 character/second)
  • Quick, where's Randy Waterhouse when you need him??
  • As far as I know, these stations have been around since the sixties. Personally, I think the numbers being read are messages for a one time pad. The intended reciever could write down the numbers between two given time periods, apply a key for that date & time and decode the message. To anyone else listening, the numbers remain a mystery.
  • by Ozone Pilot ( 61737 ) on Wednesday September 15, 1999 @05:19PM (#1679392)
    Couple of comments.

    First would be that some enterprising shortwave listeners have indeed "DF'd" these things (traced them to their source). One major source of Spanish and English language numbers stations is (no surprise) some sort of State Department or CIA (nobody is quite sure) facility near Warrenton, VA. I believe a few years ago that Monitoring Times ran a story on the guys who figured this out.

    Second, I would disagree with the statement that these are outmoded by satellite communications. You must remember that these are spy communications; as such, this is still the ideal medium. Why? First of all, should a field agent be caught/interrogated/searched, a shortwave radio is a much more anonymous travelling accessory than some strange satellite contraption. Reliability is also an issue. One can purchase a shortwave radio in just about any business district in any part of the world. What if an agent in the field loses his one-off satellite communications unit?

    Given the security that one-time pads provide, there really isn't a disadvantage to still use shortwave. Atmospheric conditions and propogation are always an issue, and at times can be less than reliable, but some of these stations are pumping out some *serious* power, and repeat their messages many times a day on different bands.

    These things have been infamous for years with the shortwave listening community. They're a little less obscure in Europe; there, the shortwave bands are much more populated (especially the low frequency ones) by broadcasters that occasionally, numbers stations have been known to have been pushed down into the standard broadcast bands. In fact, one of Stereolab's albums features a long sample of a numbers station (Transient Random Noise Bursts with Announcements if you're interested, available just about anywhere).

    Ozone Pilot
  • by kees ( 6972 ) on Wednesday September 15, 1999 @04:52PM (#1679393) Homepage
    Numbers stations on shortwave have been active
    for decades now. A lot of speculation has always
    gone around regarding where they are coming from.
    Years ago, the prevailing opinion was that they
    were North-Korean spy stations broadcasting data
    to field agents.

    Shortwave listeners have always been very
    interested in these spooky stations. There is
    an organisation called World Utilitity Network
    (WUN for short) and they publish a newletter every
    week with this kind of information. It can be
    found at http://www.wunclub.com/. For the
    un-initiated: with the term utility station we
    mean shortwave radio (30 MHz) users that are not
    amateur radio operators.

    There are many more resources out there on the
    web. Without any doubt, they are rather exciting
    to listen to. Sadly, the current tendency is that
    shortwave communication is phases out by a lot of
    these organisations in favor of satellite communications.
  • Some of the stations have been located. Virginia, Cuba and Germany are a few of the more popular locations.
  • If you buy just a cheap radio shack shortwave radio (mine was like $100 and covers two bands pretty broadly) and scan in the big empty areas, you'll usually find two or three of these stations. Being in the pacific northwest doesn't help, though, since we have the worst shortwave radio reception in the world.

    They're ueber-creepy late at night, though... and when you're listening to Agent Orange (depeche mode) on the stereo.. *shudder* ;)

  • It seems that finding the location of these stations would be easy, considering the power levels required to transmit worldwide.

    I understand that shortwave broadcast propogate rather well, but still, with a a directional antenna and a car, it should be possible to triangulate(using non-euclidian geometry! What fun!) to come up with a list of possible locations.
  • You are right that not all shortwave communications will disappear. My remark was mainly aimed at the general degradation of HF usage.

    It is interesting to observe though that some military organisations are starting to expand their presence on shortwave again. Satellites have the nasty habit of passing only once every 90 minutes and then being only visible for about 12 minutes when they have a maximum elevation of 90 degrees. And of course, if you are playing soldier on a spot where there is no 100% satellite coverage, this is a very real problem. This became clear when the operations in Yugoslavia were at their peak.

    Rumor have it that the US army is even starting to train morse code operators again....
  • by kees ( 6972 ) on Wednesday September 15, 1999 @05:11PM (#1679399) Homepage
    Well, finding the location of these stations is
    not so easy as you might say. Shortwave signals
    are refracted by the atmosphere, which is the
    first reason why it might be harder to pinpoint
    the origin. In worst case, you aim your antenna
    at the last bouncing point somewhere in the
    earth atmoshpere.

    The second reason is that because of the good
    propagation conditions on shortwave, you can hear
    the signal coming from two sides. The earth is
    more or less round, so you have a short path
    propagation and a long path propagation.

    The third reason is that the signals don't necessarily(sp?) originate from the country that
    is responsible for transmitting them. In the case
    of US stations, it is very possible that they
    are broadcast from one of the allied countries
    in Europe or the Pacific.

    Also, if you want to triangulate a shortwave
    station by car, you must realise that it very
    possible for shortwave stations to reach for
    several thousands of miles. To illustrate this,
    I spoke to an Argentinian operator from the
    Netherlands only last weekend, and I only used
    a power of 100W. These number stations habitually
    use several kilowatts. Triangulating a station
    which is several thousands of miles away needs
    pretty large legs on the triangle.

    Of course, this doesn't mean its impossible to
    determine the direction of HF signals, its just
    a nicer challenge ;)
  • In a day and age of reduced defense spending, it's smart to maintain traditional low-band facilities. Satellites, because of their complexity and cost, are not very fail-safe. One can launch a two-billion dollar satellite and deploy another 500 million worth of receiver appliances only to have the thing turn it's antennas towards Jupiter rather than Earth; necessitating a shuttle launch 18 months later at a cost of 900 million to fix it. Only to have it disabled by space debris 10 months later. It's replacement blows up on the launch-pad.

    Shortwave is pretty idiot-proof. If you have the space for an antenna, and some electrical power, you can deploy anywhere on very short notice. I'm sure the military has not forgotten this.

    Ozone Pilot
  • I would guess that a large portion of what these numbers stations "play" is random padding to prevent traffic patterns inadvertently giving away information (e.g. a large number of messages on the eve of an invasion).

    Of course this padding would be statistically indistinguishable from the OTP encrypted material they play the rest of the time, and about as "crackable".
  • maybe we should get some CIA, NSA guys on stage and have them do a spoken word over a break beat. maybe they are just artists trapped in the highly efficient and secret machinery of the first world captalist regime. I will hear navajo code talkers at my next rave. ummmmm delicious baby.
  • the Conet site got me all worked up about hearing a young girl reading off code, which i think is very spooky (yes, i know, I'm a pansy-i sleep with a night light and almost "evacuated my bowels" when watching the cartoon version of "sleepy hallow"). i just really wanted to hear that, but when i went to download the iwave player, up pops a page telling me that that the service has been discontinued. to save everyone the 'finger meets rear of throat' effect i'll skip the rest of my sob story and get to the point. Please someone send me an iwave player or the swedish rhapsody in an mp3 file! sometime in he next two days would be nice, before my reletavly short attention span releases this urge of mine.
  • My guess would be that the one-time pad is used for oh-crap-I'm-about-to-die kind of communications. Something like you call a number and say "foogle!" and mother knows to broadcast a meeting point using one-time pad 523 for agent 27 at 2300 Moscow time. Given the size of such message, the agent would probably just memorize the pad. After all, an address is only 40 or 50 bytes. I would assume also that each agent has their own one-time pad, so that capture doesn't invalidate ALL agents' pads. Seems like a very workable system to me, and you KNOW it can't be broken.
  • I've been an on-and-off shortwaver/world-band guy for a couple of years now, but this, I think, might be the absolutely coolest thing I've ever seen on slashdot. I'll definitely have to uncork my little Realistic world-band receiver and put up the big ol' antenna again after reading this story.

    -=-=-=-=-

  • by kuro5hin ( 8501 ) on Wednesday September 15, 1999 @06:19PM (#1679408) Homepage
    I can't see that the computer era would do anything but facilitate it.

    Not necessarily. A lot of people seem to have lost the distinction between sources of random data and sources of pseudo-random data in the era of the computer. Or discovered that what they thought was random really wasn't, even though they were really careful. Really, this has always been pretty much the only weakness of one time pads, though. And you can bet the folks broadcasting this stuff know where to get some grade A randomness. :-)

    ----
    We all take pink lemonade for granted.

  • The main mistake that the Soviets made was that duplicate OTP pages were sent out to various organizations when they had a shortage of pads. Encrypting several messages with the same page is a major security lapse. The ASA/NSA would find several messages, say one from AMTORG and one from the KGB, that had been encrypted with the same page. Exclusive-or the two messages to strip the OTP key, resulting in the exclusive-or of the plain text messages. Supposedly the Soviets shot the party responsible for the duplicate pages.

  • , because you have to get the pad, securely, to your recipient somehow.

    In the case of a spy or submarine, the pad could be exchanged when the recipient is in a secure location. A spy could be at his home base or an embassy, a sub could be docked in a naval harbor. Exchange pads. Send them on their way. You've got the closest to unbreakable there is.

    If an enemy country invades your embassy or confiscates a diplomatic pouch, you're at war then. In order to retrieve a pad from a sub, you'd have to board it, which is pretty unlikely unless you're in a James Bond movie. Past that, you can only sink it, destroying the pad and recipient...

    BTW: How is it that a *good* stream cipher can be decoded with a pen and paper? Doesn't sound all that good to me...
  • This kind of stuff really facinates me. Does anyone know any links to any "found sounds" archives?

    There were some links on the Art Bell web site awhile back to a recording some well-diggers made supposedly of Hell! It was obviously BS, but creepy none the less...
  • -.-. --- --- .-.. .-.-.- .. ..-. .. -. .- .-.. .-.. -.-- --. . - - --- ..-- ... . -- -.-- -- --- .-. ... . ..-. --- .-. ... --- -- . - .... .. -. --. .- --. .- .. -. .-.-.- -- .- -.-- --. . ... --- -- . -.. .- -.-- .. .-- .. .-.. .-.. ..-- ... . -- -.-- . -..- - .-. .- -.-. .-.. .- ... ... .-.. .. -.-. . -. ... . .- --. .- .. -. .-.-.- .-.-.- .-.-.- ... .. --. .... .-.-.- .-.-.- .-.-.-
  • Since WW2 it has been standard practice for field operatives sending and receiving traffic over totally insecure channels in this manner to use one time pads.

    If it's just an endless stream of numbers I doubt it is a one time pad.

    Think about it. This is probably used to communicate with many different agents, all of whom would use different codes. If it were a OTP, how do you know where your message begins except by attempting decoding at every point? Too tedious.

    This is the first I've heard of numbers stations, but my guess would be that it's codebook based. That is, each agent would memorize a list of codes like this:

    74123: Meet in the park at 4 PM
    12486: Meet in the library at 10 AM
    60789: Go to dropoff point
    53726: Proceed with phase 2
    83655: Disregard previous instructions
    07991: Get the hell out of dodge

    Then each agent would just listen for numbers that match one of his codes. Other numbers may be instructions for other agents, or may just be random cover traffic.

    Easier to use than a OTP and no need to write down incriminating streams of numbers from the radio.

    I seem to recall that something like this was used to communicate with the various resistance cells during WWII, though I think it was code words rather than numbers.

  • I had actually heard of this release before on a music mailing list (IDM). My understanding was that it was really limited (like 500 copies), and I wanted to get it, but it's 50 dollars, and it's just numbers, so I put it low on my list. I'd figure it's sold out by now, but your favorite IDM outlets may still have a copy.
  • by Anonymous Coward
    Rumor have it that the US army is even starting to train morse code operators again....

    While I agree that the above statement is probably true, it is very curious to note that as of this fall, learning Morse code is no longer required at the US Naval Academy or at West Point. (I don't know about the Air Force Academy) It will be interesting to note if the military academies quickly add this topic back to their requirements.

    only visible for about 12 minutes ... no 100% satellite coverage...

    Interesting. While in northern Italy last summer, I watched a US Army Major I was traveling with use a satelite phone continuously for several hours. This phone looked like a laptop with the dish concealed in plastic where the screen would normally be. No, I don't remember the manufacturer's name. He didn't have a problem with "no 100% coverage" with his consumer-grade satellite communication system. I'm very curious as to why the US military's system would be much more limited than a cheap (relative, I was told the sat. phone was only $12 per minute to anywhere in the world) consumer system.

  • by MDX-F1 ( 87940 ) on Wednesday September 15, 1999 @06:59PM (#1679418)
    Here's a link to a pretty cool site I've had bookmarked. It's got RealAudio files of numbers stations, as well as clandestine stations, unidentified broadcasts, etc:

    http://www.cisquet.demon.nl/soundsframe .htm [demon.nl]
  • Is this just speculation, or do you have first hand experience? In my opinion one-time pads are *less* secure than public-key or symmetrical block ciphers. This is because the one-time pad must be protected and carried around, while a single key can be easily memorized. Yes, you can use a block cipher to protect your one time pad, but if you trust block ciphers for that, why not trust it all the way?

    Most compromises of secret information involve people - not fancy algorithms, and one-time pads are a real people problem. They are easily lost, destroyed, stolen, or exhausted.
  • There's a plot for a neat thriller in this ;) The guy who could overhear secret communications...

    I wonder what other sort of bizarre communication techniques are being used. Perhaps there's some huge rigs someplace in the world thumping out morse code for a spy with a stethescope or seizmograph.

    I don't know if I can hear the humming, the voices in my head tend to drown anything else out.

  • by cluke ( 30394 )
    Have you seen a doctor about it? It may be something like tinnitus : "a sensation of noise (as a ringing or roaring) that is caused by a bodily condition (as a disturbance of the auditory nerve or wax in the ear) and can usually be heard only by the one affected "
  • Let's see... $12/minute for several hours (say 2) equals... $1440. Sheesh. No wonder the defense budget is so high. Get that guy a cell phone!
  • Interesting. While in northern Italy last summer, I watched a US Army Major I was traveling with use a satelite phone continuously for several hours.

    You are probably right, but the system that he was using is probably a system that consists of more than one satellite. More or less comparable to cell phones. The Iridium network is such a initiative. They make sure that at any one time at least one satelite is visible over the horizon. Problem is that Iridium is a public network and not a military one. I dont know if the military has similar networks of their own.
  • by Anonymous Coward
    Given enough satellites you can have them in geosynchronous orbit (they stay at the same position over the Earth all the time) and still cover every square inch of the Earth's surface. GPS has 24 satellites, right? I've gotten GPS locks with 5 satellites simultaneously so 24 divided by 5 is 5. With simply 5 satellites in geosynchronous orbit, you should be able to cover the globe allowing for continuous satellite communication links worldwide.
  • There was a guy on the newsgroups a few years back giving away a CD called "Dog Pound Found Sounds" or something similar. It's basically two CDs of sounds from a pound. Unlistenable, and I can listen to almost anything. It was somewhat equivalent to open source music, in that the guy had no copyright and wanted it sampled, spread as far as possible, etc. If you email me and keep me on it, I'll see if I can find it. I think I gave it to a friend, but you might be able to still get a copy.

    This Hell recording sounds intriguing/amusing...
  • Think about it. This is probably used to communicate with many different agents, all of whom would use different codes. If it were a OTP, how do you know where your message begins except by attempting decoding at every point? Too tedious.

    Simple actually: My messages will always start at 12 minutes past every even hour (UTC), and the first three letters will always decode to 'NNN'. If I start decoding at the appropriate time and the letters don't match, it wasn't for me.


    ...phil

  • You still may be able to find links to the Hell recording at Art Bell's web site [artbell.com].
  • Reading this article reminded me of something even more interesting. Around here in our evening newspaper, there's been a message floating in the Announcements section in the classified ads for the past few months. The message reads as follows

    The Oil is Shot
    ConserVation R Ancientis Best
    No Ala-R-min But Oil is all Orbit

    Anyone experience anything similar in their newspapers? Can anyone figure out what this means? I'm starting to wonder now just how many encrypted messages we see in a typical day. I'm guessing this isn't the only one.

    By all means, we should have a right to encode messages to send them back and forth, but when the encrypted messages appear in public such as this, or as in Number Stations, does it do something to decrease overall public morale? I see it as a challenge to decipher, but because I'm not the intended destination of the message, there's something about doing so that sends a shiver through my body...

    In any case, it does little but add fuel to conspiracy theories. What we don't know may not hurt us, but what we see and aren't intended to know are the things that haunt, and even frighten us.

  • Reading this article reminded me of something even more interesting. Around here in our evening newspaper, there's been a message floating in the Announcements section in the classified ads for the past few months. The message reads as follows

    The Oil is Shot
    ConserVation R Ancientis Best
    No Ala-R-min But Oil is all Orbit

    Anyone experience anything similar in their newspapers? Can anyone figure out what this means? I'm starting to wonder now just how many encrypted messages we see in a typical day. I'm guessing this isn't the only one.

    By all means, we should have a right to encode messages to send them back and forth, but when the encrypted messages appear in public such as this, or as in Number Stations, does it do something to decrease overall public morale? I see it as a challenge to decipher, but because I'm not the intended destination of the message, there's something about doing so that sends a shiver through my body...

    In any case, it does little but add fuel to conspiracy theories. What we don't know may not hurt us, but what we see and aren't intended to know are the things that haunt, and even frighten us.

  • hmm... since the signal bounces of the atmosphere it gets to you from several directions but with different pathlegths depending on the direction. wouldn't it be possible to build a bi-directional antenna and put the signals coming from different directions through an interferometer to pinpoint the source?
  • There is one major problem with geostationary satellites and that is that they are at a distance of several tens of thousands of kilometers. For one-way communication such as TV broadcast, that is not a problem. When you use them for two-way communication such as telephony, the delays will get so large that they are noticable. Especially when the conversation is going back and forth quickly that is a realy problem. But we digress from the orignal post ;)
  • I have to agree with you. It's certainly not obvious that these codes are one-time pads, because you have to get the pad, securely, to your recipient somehow. Obviously, they can't easily get information to their recipients, or else they wouldn't need to broadcast to them this way.

    I'm guessing that it's some kind of stream cipher. With a stream cipher, you just start with a key and go from there as long as you need to. Some good stream ciphers can be decoded with pen and paper, and I would guess that these spooks aren't able to carry around little computers or code books. And the spook agencies have been using stream ciphers for many decades now, they probably have some very good ones.

    BTW, I've heard these stations on shortwave myself, ever since the seventies. With all the whirr and buzz I had on my cheap shortwave sets as a kid, it sounded real spooky. Wouldn't want to hear it any other way.
  • Yes. It's either a tape recording or now computer generated, but it's definitely a human voice. The numbers are usually in Spanish.


    ...phil
  • ELF transmissions go out in Oahu at a marine base off of Hammerhead Bay. The attennae is about .75 mile across with ~ 5 interconnected arrays. The mountains form a horseshoe with the attennae connected between these peaks. The transmissions are so low frequency, as the other poster noted , that the frequncies are transmitted throught he ground.I believe they are also now using blue green lasers from orbit to communicate the flash traffic as well.As an aside, the mountain has a set of ladders going up 3000 ft which you can climb (they call it the stairway to Heaven on the base). Great fun, takes about 6 hours up and down. The controller for the array is at the end of the Stairway.
  • Actually this sounds quite spooky :))
    You can find a link to the Swedish Rhapsody here [easyspace.com] (in Real Audio).

    I'm gonna buy a radio I guess ;)
    --

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