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U.S. Government Sometimes Jams Keyless Car Locks?
Posted by
CmdrTaco
on Mon Jul 05, 2004 02:27 PM
from the can-they-jam-cel-phones-too-please dept.
from the can-they-jam-cel-phones-too-please dept.
PizzaFace writes "The Washington Post reports that in certain towns (generally near military bases), on certain days (such as the day an aircraft carrier returns to port), keyless car entry systems and remote garage door openers mysteriously fail. While some frustrated motorists blame aliens, the FCC says the jammed frequencies belong to the U.S. military. The good ol' Post even tracks down a government contractor who all-but-confirms the source of the interference."
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fp (Score:5, Funny)
[JAMMED]
This might explain why (Score:5, Interesting)
Re:This might explain why (Score:5, Informative)
My buddy has the exciter from a shipboard radar as his "Ham Radio" rig. This item generates 1000W CW and about 100 KW in pulse mode, which is what the radars use. It has 4 sections that each handle 1/4 of the band from 10 Khz to 1 GHz. That was then fed to a 10KW Power Amplifier and out. Just the exciter part sits in 3, 6-foot rack cabinets!
The average pulse power in the radars is around 100,000 Watts, and can be pumped up several orders of magnitude to "burn through" jamming if necessary (peak pulse power levels around 1 GWatt!) That field is being constantly swept around the area looking for threats using phased array panels, much faster than the old "Battlezone" radars, so the RF field is effectively everywhere.
Key fobs, RF remotes and Garage door openers are using the 330 Mhz junk band and are right in the middle of the Military A-Band. Doh! Unfortunately, they are also Part 15 users of the spectrum there, and are secondary users of those frequencies - they must not interfere and must accept any interference they experience. Double Doh!!
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Re:This might explain why (Score:5, Informative)
We had rock bands come to us (near a Canadian base).
About 3-4 miles from the hotel was a NORAD RADAR. The pulse from the RADAR would manifest itself as a "BZZT" in the band's amplifiers (If was funny seeing the band try to locate the source.....). Heck, you could hear it on your car radio.
Big wattage is NO joke. The spill-over into other freqiencies is a fact of life (anyone with a CB will know it as cross-talk).
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Re:This might explain why (Score:4, Funny)
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Re:This might explain why (Score:5, Informative)
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Re:This might explain why (Score:5, Informative)
Aircraft carriers have a good deal more power than one would think, and certainly more than a Tico, which is about medium size. One thing to note is that there is no "Medium" size for Navy ships, there are small guys, and big guys. CVN, LHD and LHA are going to have more power because they are bigger...the LHD I served on had 5 primary generators rated at 2500kW a piece, plus another 2 backups at 2000kW each. LHAs are similar, but CVNs have even more, mainly because they have fuel to burn, being nuclear.
Oddly, in the radar category, its only the smaller ships in the Cruiser Destroyer community that have phased array radars, which have higher output than those found on other ships. On carriers, the primary high output radar is the SPS-48E (a rotating radar, as all are, with the exception of the SPY-1 series), and has such power because it is an Air Search radar that scans in 3-D. There are ranges at which we are required to turn off our radars in vicinity of land, but this is soley at the attentiveness of the watchstander, and we frequently got reports during Operation Iraqi Freedom thaty our 48E was jamming the airport radars in Kuwait, and we were requested to lower the power output.
Anyway, a carrier pulling into town running a 48E could certainly jam such devices, but more frequently we get reports that devices start *operating* without warning (garage doors opening, etc.) Certainly you'd see these things more often if you worked on a Naval Base, since lots of ships tend to pull in and out there.
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Re:This might explain why (Score:5, Funny)
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Re:must accept? (Score:4, Funny)
In other words, "If you don't like it, lump it" (I think that's how the old saying goes), or "this is the world's smallest violin...", but in legalese.
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Re:This might explain why (Score:5, Informative)
Basically, if a primary user's signal interferes with a secondary user, the secondary user is the one responsible for dealing with the problem (e.g., shielding their equipment, moving, etc). The primary users don't have to take any steps to avoid interfering with secondary users.
Secondary users, on the other hand, have to avoid interfering with primary users. If a secondary user interferes with a primary user, the secondary user has to stop, shield their equipment, move, etc.
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Tin Foil Hat Time ! (Score:5, Funny)
Re:Tin Foil Hat Time ! (Score:5, Funny)
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When you can't (Score:5, Insightful)
Re:When you can't (Score:5, Insightful)
My brother had one installed, and I asked him what he'd do if his remote's battery ever went dead.
He shrugged and said he'd buy new ones at the store... but stores arent always opened when Murphy's Law decides to apply itself.
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Re:When you can't (Score:5, Funny)
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Luddites rejoice (Score:5, Funny)
Forget part 15... (Score:5, Interesting)
Re:Forget part 15... (Score:5, Informative)
No, not really. The purpose of Part 15 in this case is to protect the military (or whatever individual/group/organization is assigned the particular frequency(s)) from interfearance that your keyless entry system might produce. It is not meant to protect your keyless entry system from others who may be using their assigned spectrum properly.
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Re:Forget part 15... (Score:5, Informative)
So, it all comes down to what frequencies the car alarm makers are expecting to use. If they pick a miliatary frequency and are trying to use it at low power, then they can't really complain when a miliatary ship comes by and blows them out of the water bandwidth-wise. However, if they pick a frequency open to the public like the 900mHz band, then it's the military transmitting too strong on a low-power band, even if it's just the result signal splash from their attempt to use their assigned band at high power.
So, in a sense, Part 15 does protect your keyless entry system from the miliatary. They're supposed to keep their RF operations away from your space just as much as you're supposed to stay away from theirs.
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Re:Forget part 15... (Score:4, Interesting)
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Re:Forget part 15... (Score:4, Funny)
It should, just not in the way you're thinking:
Whatever they had running was so strong, it completely fried the system.
That's what the "must accept interference" part comes in.
Of course, the idea of going to Olds and saying "Your stuff violated part 15 because it didn't accept FCC-legal interference. So replace it with something that does, or I'm siccing the FCC on you!" is probably not terribly workable.
Might be fun, though.
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Stratcom Jamming (Score:5, Interesting)
He explained on several occasions that one of their amusements was lowering a long antenna and jamming garage door frequencies and other civilian applications (e.g. keyless door locks). I couldn't imagine why the air force would want to interfere with garage doors and he never had a good explanation other than they were told to do that and the crew always found it amusing.
Urban legend? Looking Glass crew tall tale told to amuse their friends? Who knows, but they certainly had the ability to try and lord knows many friends have had their garage doors open by themselves in the middle of the night.
Jams? (Score:5, Insightful)
When 2 ethernet NIC's transmit at the same time in normal operation we don't call it jamming. I doubt that what the government is doing is intentional.
Re:Jams? (Score:4, Interesting)
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Re:Jams? (Score:5, Insightful)
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Re:Jams? (Score:5, Informative)
The car entry system makers picked a frequency that belonged to the military as the primary user... they can't really complain when the military comes to town and wants to use their channel.
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Re:Jams? (Score:5, Funny)
I know that was just a typo, but I nearly wet myself laughing, anyhow...
Somehow I picture Linus (the "Peanuts" character) as the captain of an aircraft carrier, exerting his "blankey control".
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Re:Jams? (Score:5, Informative)
The generally held concept for emergencies is "anything goes", but you better be prepared to answer for and justify your actions later on.
The other is the military. They don't have "band limits" on their signals. They have generally decided on a band plan that doesn't interfere with other services, but any frequency that is not desginated as broadcast, amateur or public service is subject to them usurping any time at their discretion. Even some of the amateur frequencies are primarily military designation and amateurs are secondary users (parts of 440 Mhz and others).
At the risk of being flamebait, remember, they're the U.S. Government and they can do whatever the hell they want.
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I think this says it all... (Score:5, Insightful)
Conspiracy! (Score:5, Funny)
hmm (Score:5, Interesting)
Weird.
Garage door remotes (Score:5, Interesting)
In Eastern Europe... (Score:5, Interesting)
A story (Score:4, Interesting)
Re:A story (Score:5, Interesting)
I am suprised at your story though. Navy procedure for radio links involved the fuses being put in control of the watch officer who ensures that they don'tr get returned until after everyone is down.
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Re:A story (Score:5, Informative)
I've seen the outcome when the Red Tag procedure is not followed, it cost a friend of mine his hand.
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Doesn't matter. (Score:4, Funny)
I worked at a branch of the military for a while. During one of the status reports, I heard this story:
Two repair techs lock out the machine they're working on with padlocks and put the keys in their respective pockets. Once they're done the repair, they go to turn the lockout off, and...
"What the [pretty flowers]? The [fluffy bunnies] padlocks are [cute kitten] missing!"
They searched the ship, and they found a drawer full of bent, broken, and damaged padlocks. It didn't belong to anyone, but it was a real WTF moment. Not only did someone ignore the lockout routine, but the guy pried open the padlocks to turn the locked out machine on.
They never found out who did it.
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semi-dupe (Score:4, Informative)
Obligatory Spaceballs Quote (Score:5, Funny)
Dark Helmet: "Jammed? Raspberry. There's only one man who would dare give me the raspberry. Lone Starr!"
For sale.... (Score:5, Funny)
Depends on the car... (Score:5, Interesting)
One of those shows that copy MTV's Punk'd concept did a thing like this with retail CB walkie-talkies. They went to one of the big parking lots downtown and when a car's owner approached his vehicle, they just hit the speak button on the CB radio and held it down. Then, when the car wouldn't open, they'd send a fake locksmith in who'd pretend to mess with the lock for a while, eventually give up and then offer to smash in one of the windows.
In most cases, that one walkie-talkie was enough to "jam" the keyless entry system. The only cars it failed to work on were Mercedes, BMW and IIRC Audi models (maybe imports use a different frequeny - I dunno).
Surprisingly, most of the people couldn't seem to figure out how to get in their cars without the remote (well, at least, of those people they showed). I sometimes wonder how those people manage to put their pants on in the morning.
Could be fixed if they spent more on the receiver (Score:5, Interesting)
The particular frequencies used depend on where in the world you are; the U.S. uses one set and the rest of the world uses another. Here in the "rest of the world" most remotes operate at 433 MHz. This is not far from TV frequencies - ever find your car remote doesn't work if you're parked next to a TV transmitter? Newer systems will probably be using 868 MHz (rest of world) or 913 (U.S.); this bit of the spectrum is better regulated and it would be difficult to get away with not using a crystal-based receiver. So hopefully these problems will go away.
Re:Medical devices (Score:4, Informative)
That being said? I find it highly unlikely that a critical device like that would be left to "We can just sneak along on any frequency we want, because we put out less than 1w"
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Re:Medical devices (Score:5, Informative)
This is one of the reasons medical devices have to go through some rigorous testing and use approved frequencies. Even so, mistakes do occur.
When a pacemaker fails, it tends to get noticed. Early pacemakers had trouble with improperly shielded microwave ovens - mostly because the pacemaker itself was improperly shielded. Pacemakers that used a magnetic sensor for the on/off function ran into trouble if a strong magnet was waved over the patient's chest. Some of the early AV sequential pacemakers with the ability to change heart rate based on activity sensors would, if incorrectly programmed, suddenly throw the patient into an artificial 2nd degree heart block when the patient's heart rate exceeded a specific amount.
Urban legends contribute to percieved problems. Notice all the hospitals with "No Cell Phone" signs. Then notice all the cell phones in use by the doctors and the EMS personnel walking around with Handi-Talkies. Oops....
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Re:Medical devices (Score:5, Informative)
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Re:The manufacturers should be arrested! (Score:4, Informative)
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Re:Top 10 most stolen cars (Score:5, Insightful)
I have three rocks in my garden. All of them are red. None have been stolen. Ergo, red rocks cannot be stolen.
See how stupid it sounds? Dude - the top five cars on that list are also the TOP FIVE most common cars in the U.S. If you can establish a relationship between the theft rates of similarly-equipped cars, where the only variable is RFID or not, then you've got a case and you are welcome to tell us all about it. If you just wanna spout uneducated shit...
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Re:Mercedes 200E - V. Nice but electronic key (Score:5, Informative)
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Re:I once had a car alarm (Score:5, Insightful)
When the air-show came to town, there's usually some military aircraft included in the group whose favorite comminication frequency just happens to be the one your car alarm is tuned to.
Therefore, the car alarm thinks it's always being challenged by the random noise that is really the pilots talking to each other...
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Re:i knew this was going to happen (Score:5, Informative)
For an excellent example, hams were in the last couple years authorized to operate on the 60m band. That probably means nothing to most people, but it's a specific band that is used by amateurs in other countries, with its own unique propagation characteristics. However, amateurs, who generally get the run of whatever band they're allowed, are limited to one particular operation mode (upper sideband) on five channels, one of which is shared with the UK making international contact on that band possible. The reason for the limitation: the primary users on that band are military and emergency-related, they use upper sideband on those frequencies, and they need to be able to clear the channel for their own use, so they have to be able to talk to other users. (It's an annoyance to hams, who are used to being able to operate any mode they wish, but c'est la vie.)
What looks like the case here is that the remote systems are designed to operate under Part 15 rules, which govern general unlicensed transmission. They're the same rules under which a community low power AM station can broadcast, and are subject to the same terms. In this case, it was an unfortunate choice for car manufacturers, because the frequency chosen is apparently used for certain FCC-allocated classified purposes. Oh well.
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