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How to Jam a Worldwide Satellite TV Broadcast

Posted by timothy on from the next-on-the-diy-network dept.

An anonymous reader submits: "According to an MSNBC article, 'it's simply a matter of aiming a strong signal at the uplink transponder on the satellite and overwhelming the...broadcaster's signals...You need a dish, some power, not too much. You put up a test pattern ... and do a sweep and find the transponder on the satellite you want to jam. It could even be smaller than the standard 6-meter dish. It could be a small dish with a lot of power.' This was apparently how an Iranian satellite television station was knocked off of Loral Skynet's TelStar-12 a few days ago. Loral contacted TLS, a company which specializes in satellite broadcast security, who quickly located the source of the jamming to Cuba."

6 of 326 comments (clear)

  1. Already been done here... by Rorschach1 · · Score: 5, Interesting

    See the story of Captain Midnight and HBO..

    http://www.signaltonoise.net/library/captmidn.ht m

  2. The tricky thing is.... by PS-SCUD · · Score: 5, Interesting

    How do you make this illegal? If they can beam their signal onto your house, why can't you beam yours at them?

    --


    "Much work is lost, for the lack of a little more." -Edward H. Harriman
  3. cool , but much cooler things can be done (DSS!) by pigscanfly.ca · · Score: 5, Interesting

    such as using the transponders to carry your own signal . Most sat tv satelites are essnetially dumb transponders , which means (essentially) they receive a signal on one end and pump it out the other end . What is cool is that using DSS (direct sequencing spread spectrum) you can transmit your own data and people will think that it is background noise . I beleive correctly some russians were doing this awhile back and it went on for a couple of years before they got caught.

  4. Countermeasures by td · · Score: 5, Interesting

    As has been pointed out, people have been jamming satellite uplinks since Capt Midnite & HBO. So why haven't the satellite folks gone to jam-resistant technology? (I know, it's because of the essential laziness of corporate culture -- geez, it was a rhetorical question.) Spread spectrum is essentially unjammable, if done right (i.e. with cryptographically generated spreading sequences or some such cryptogeek mumbojumbo.)

    --
    -Tom Duff
  5. Jamming from Cuba, the how and why by InklingBooks · · Score: 5, Interesting
    I once asked a friend who designed satellite antenna system what it would take to take over a channel and he said it would be fairly easy. The typical uplink is 30 watts into the sort of large dishes you see at TV studios. Because the link is FM (regular TV is reduced carrier SSB), a signal about twice as strong would 'capture' the receiver and the legitimate signal would simply disappear.

    What's really intriguing about this story is the Cuba/Iran link. For years we've been told that religious extremism in the Middle East was a close kin of religious conservatives (Jewish and Christian) in the US. Yet when Iraq's brutal dictator recently began to cloak himself in Islamic rhetoric, it was primarily the political left in the US and Europe, who wanted to see him left in power. Their old love affair with Stalin was turned on to the foul Saddam.

    Now Iran, an Islamic theocracy, is having trouble with dissidents demanding democracy and who comes to its aid but virtually the only remaining Communist dictatorship in the world.

    Very interesting. It seems that some groups simply want to see the great mass of people regimented and are indifferent to the ideology used to justify the regimentation. Religious or secular, Marxist or Facist, it is all the same to them. Mussolini was, after all, a communist before he was a facist and Nazism had people who were called "beefsteak Nazis"--brown on the outside and red inside. Then there is the Hitler-Stalin pact of 1939. Hitler may have intended to break it at the earliest opportunity, but Stalin seems to have been sincerely surprised when Hitler broke it.

  6. Surprising it hasn't happened sooner by jordandeamattson · · Score: 5, Interesting

    While watching the Tinammen Square Massacare and then discussing it at MacHack in 1989, we discussed the fesability of not just taking Chinese television of the air, but actually taking control of it and getting the real message of what was happening out to the world.

    After a few hours of discussion with some extremely bright folks, we came to the conclusion that 1) it could be done, 2) that it could be done easily, and 3) that we really didn't want the Chinese security services and the US Department of State and the FCC all coming after us.

    What is surprising, is that this hasn't yet been done in any large scale way. The reality is that small forces of 2 and 3 people can wreck havoc in our increasingly connected world. I believe that what keeps this in check is the level of concerns that kept us in check. But what happens we you don't have those concerns? When you have nothing to lose? Then you have the cyber-equivalent of the Palestenian sucide bombers.