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Distress Signal Emitted By Flat-Screen TV
pinqkandi writes "CNN is a running a story on an Oregon college student's flat-screen Toshiba TV which was releasing the 121.5 MHz international distress signal. He was unaware of the issue until local police, search and rescue, and civil air patrol members showed up at his apartment's door. Apparently the signal was strong enough to be picked up by satellite and then routed to the Air Force Rescue Center in Virginia. Quite impressive - luckily Toshiba is offering him a free replacement."
It's well known that certain hardware hacks for Dishnetwork receivers emit this same frequency.
What a coincidence that a college student (no money) would be doing something technical (education) to get TV for free.
If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
We just spent $10K+ on in-house EMI equipment, to mitigate the costs of having an outside lab help with troubleshooting.
You have to do it if you make any kind of electronics, but it's a big burden for small manufacturers.
It'd be nice to have the choice of saying "this passes" vs "this probably passes". Current FCC/CE regs require everyone to meet the spec, and this is a bit onerous IMHO. It locks some innovative small companies out of the game.
And even more depressing that someone would choose to see the capability of receiving a distress signal as something other than a good thing (TM).
-- "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." -A.Einstein
i have talked a few times with someone who worked in the TSCM business (surveillance countermeasures). these are the real guys, not the ones you see with the $99 bug detector. the standard range that they now perform sweeps in goes from DC-300 ghz. i was naturally very interested in what they would be looking for above 30ghz and while the person i talked to admitted that he never personally found anything up in those frequencies, it was well known in their community that such devices were known to exist though they would likely be the domain of only the top government agencies. at any rate the device that he described would look something like the size of a coin and be able to send data in the high ghz range using spread spectrum burst communications directly to an overhead LEO satellite; essentially the ability to bug someone from space using areas of the spectrum that most would never look at and even if they did would likely never actually "see' the transmission unless they were lucky enough to see it transmitting and then only if they were knowledgable enough to recognize the signal from the surrounding noise. scary, huh...
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It was really funny to watch them play DVDs to test out the screen because they would always have the "this video not meant for public viewing" warning before broadcasting it out to the entire south side of Fayetteville. :)
There are two types of people: those prepared for the zombie apocalypse and those who will be eaten.
IIRC, the FCC had to threaten the cable operators with "unfortunate consequences" if they didn't fix their leaky systems. My local cable company started using quad-shielded coax and quality connectors instead of the cheap crap that they used to use. They also replaced a lot of their distribution plant with new equipment.
Mea navis aericumbens anguillis abundat
I am not sure if you have ever listened to marine radio near an ocean, but just from my time near the water and listening in, the US Coast Guard has about 10 ELT (121.5MHz) distress signal activations per day, per Coast Guard Group (IE, San Diego Group, Los Angeles Group, etc). They send someone to investigate each one, eventually, and they are all nearly accidental or malicous trips, not real emergencies. It has almost reached the point of too many cries of wolf.
Nick
Butte County Search & Rescue
The new systems cost thousands of dollars compared to the $50 for the old style transmitters and the new ones aren't selling well. The 121.5 systems are still outselling the new ones even though every boat dealer explains it won't work in a few years. The big problem with 121.5 is they never took the easy route which is to interrupt the carrier every few seconds with a fast cut out circuit and put some detectors on the GPS sats. That would give about 1000 meters of accuracy on the 1st signal and a bit of processing could reduce that to 100 meters which is as good as the new system in most cases and the transmitters would still only be about $50.
121.5 is very well monitored. For one thing almost any aircraft that has a radio that its not using for something else will probably have it on the guard frequency. This is a post 9/11 thing for the most part but a good one. IF you do broadcast on 121.5 every airliner up at 35,000 ft within a few hundred miles may hear you. One of them will relay your message to someone who can help you. Thats a very good thing!
On the minus side sometimes a pilot will broadcast on 121.5 becuase he thought he was trasnmitting on the other radio. (Been there, done that)
Erlang Developer and podcaster
"The Minions of Satan, I mean Time-Warner Cable"
I'm not directed this to you, so please don't take offense. But its comments like these that I hear often that basically state that cable companies are evil and greedy. I'm not saying you're saying this, but for the most part that's the kind of flak I hear about TWC.
What most people don't realize is that paying for the fiber and coax, installing it yourself, and maintaining it costs major money. And trust me when I say Mother Nature causes havoc on our network (slow modems, disconnects, poor reception, macro blocking = very irate customers). Also, TWC does NOT make money on TV stations. Where we do make our bread and butter is on the recording features and on-demand access, but also on the Road Runner subscriptions. Other then that, your local cable company in large cities are nothing more then a conduit for capturing content from satellite and piping it through your home. Also, lets not forget the employee and leased equipment expenses as well that customers are having to pay.
I'm not saying TWC isn't a profitable business, because it is. But it's not like we are making hand-over-fist either. There is competition in Austin, and we know it....which is a good thing for the customer as a whole including myself. But please, would people stop this 1980s concept of cable companies being a monopoly!
Life is not for the lazy.
This sort of thing is quite common.
One of my old friends came home to finding his home in a mess after local authorities gained entry to investigate a signal causing interference with a local airport about 3 miles from him.
The issue ended up being a problem with his cable box, which they had figured out before he even arrived.
When tuning along the dial, these signals can be heard at specific intervals. The interval spacing is the fundamental frequency. Each point is a harmonic. In this case it does not "just happen" to be at 121.5 MHz ... it is at 121.5 for a reason, and that is because the 7722nd harmonic of the horizontal sweep frequency is 121.5 MHz.
Which harmonics are stronger does depend on the waveform of the involved signal. A sawtooth is going to have a fast rise and slow decay. And that fast rise time can favor those harmonics that happen to have intervals around where harmonics of a waveform which had both fast rise and fast decay with the same time interval would show up (a higher frequency and this a larger spacing).
now we need to go OSS in diesel cars
> It turns out it got stuck on the Lifetime
> network, so it really was in a state of
> distress.
I had a TV (also by Toshiba, coincidently) that would crash when it showed the local community channel. When that happened, it did not accept any key presses on the remote or on the TV set itself, so I couldn't change the channel anymore.
Basically, my TV forced me to watch the horrible Hamburg community channel.
I complained to Toshiba and it turned out that this channel aired a non-standard Teletext that had the ability crash this particular TV's teletext decoder.
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And even more depressing that someone would choose to see the capability of receiving a distress signal as something other than a good thing (TM).
This is /. I've seen people argue in favor of getting rid of 911 because they don't think they should have to pay for something they rarely use when the injured person/person being raped/person reporting a lost child could just as easily look up the seven digit number for the local authorities. I mean gosh that E-911 charge on my last bill was like $1.49.
Nobody ever said people were logical. Politics and human nature aside I want to know how powerful of a signal this thing was putting off -- what kind of receive gain do you suppose those satellites have?
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Why did they expect to find a boat/plane in a apartment building?
Boats can be hauled by trailters to various places, including parking lots. Somebody working on their boat in the parking lot could accidentally set off the emergency beacon. Airplanes can and do crash, although crashing near an apartment complex without being noticed might be a bit of a stretch.
At the point the signal is localized to an apartment building, its probably pretty clear that it is not an intentional distress signal (although I suppose somebody could have been kidnapped and found an emergency beacon sitting in the kidnapper's closet...). They still need to find and disable whatever is creating the signal, though, to avoid interfearing with a real distress signal in the future.
Come test your mettle in the world of Alter Aeon!