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U.S. Government Sometimes Jams Keyless Car Locks?

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."

22 of 349 comments (clear)

  1. fp by Zorilla · · Score: 5, Funny

    first po#@)(^*ESDHLKS&^$#HLFSDIHF

    [JAMMED]

    --

    It would be cool if it didn't suck.
  2. This might explain why by evil+crash · · Score: 5, Interesting

    Mine don't work in the parking lot on the military base I work on, but the work fine at home.

    --
    "Anyone who is capable of getting themselves made President should on no account be allowed to do the job."-THG
    1. Re:This might explain why by Mister+Transistor · · Score: 5, Informative

      The interference is in the Military A-Band, which covers 233-403 Mhz. This is used for shipboard radars, as well as radar at airfields. You don't have to use Ghz frequencies for radar, in fact the first WWII radars used were around 100 Mhz, IIRC.

      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!!

      --
      -- You are in a maze of little, twisty passages, all different... --
    2. Re:This might explain why by RetroGeek · · Score: 5, Informative

      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

      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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    3. Re:This might explain why by HazE_nMe · · Score: 5, Informative

      I work for Chamberlain who makes the Liftmaster and Chamberlain garage door openers. Our newest units just started using 420MHz. I had an old 330MHz unit and my range sucked, so I installed a 420MHz logic board and my range more than doubled. I live right next to Davis Monthan AFB which gives me all kinds of RF interference. I suggest to anyone who has trouble with their Chamberlain, Liftmaster, or Sears GDOs then call Chamberlain and find out if you can upgrade to the 420MHz boards on your model. The price of the boards is crazy expensive ($70), but we here at Chamberlain can give discounts at our leisure. We sometimes will give one out for free if the conditions are right. (WHINE, WHINE, WHINE, "But I can't afford THAT!", "$70?!, The whole unit was $150!", etc)

    4. Re:This might explain why by rpdillon · · Score: 5, Informative

      A lot of posts to reply to, but basically, Naval Ship radars function on lots of bands, not exluding the A Band, mentioned above.

      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.

    5. Re:This might explain why by Ancil · · Score: 5, Funny

      peak pulse power levels around 1 GWatt!
      Careful with that thing. 210 MWatts more, and you could end up in the year 1955 making out with your Mom.
  3. Tin Foil Hat Time ! by Jesrad · · Score: 5, Funny

    I hear you get good prices when buying tin foil in large orders. I'd probably need that for the garage door.

    --
    Maybe we deserve this world ?
  4. When you can't by dark404 · · Score: 5, Insightful

    enter your car, and start it with just the key, the government may be to blame, but you need to be slapped.

    1. Re:When you can't by Tlosk · · Score: 5, Funny

      so buy the replacement now and stick it in the glovebox

  5. Luddites rejoice by Anonymous Coward · · Score: 5, Funny

    Horse and buggy remains unaffected by such measures.

  6. Forget part 15... by irving47 · · Score: 5, Interesting

    Too bad part 15 of the FCC's guidelines can't apply. The whole "may not cause harmful interference" section might have been nice. My dad parked on a Navy base with his keyless entry-equipped Oldsmobile for a few years up in Washington. Whatever they had running was so strong, it completely fried the system.

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    I had a sucky sig.
  7. Stratcom Jamming by Anonymous Coward · · Score: 5, Interesting

    I used to work with an engineer who was a former air force tech on the Looking Glass. The Looking Glass missions were a group of USAF command/control aircraft that was always airborne to provide a redundant facility to the Strategic Air Command (SAC) in the unlikely event SAC ceased to exist from a USSR strike.

    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.

  8. I think this says it all... by stoneymonster · · Score: 5, Insightful

    "But unlike other more powerful radio signals, keyless entry remotes are not licensed by the Federal Communications Commission. They are allowed to operate on frequencies used by licensed customers as long as their signals are sufficiently weak and don't interfere with others. But because of this outlaw status, their own signals can be jeopardized." Tough. Get licensed, or have a working backup system that doesn't depend on radio. I honestly don't see the issue here. The situation isn't likely to change, so the unlicensed folk will have to work around it. Use spread-spectrum at low power or frequency hopping to get around this. -C

  9. Conspiracy! by pyrrhonist · · Score: 5, Funny

    This will be in Michael Moore's next film. </satire>

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    Show me on the doll where his noodly appendage touched you.
  10. Obligatory Spaceballs Quote by Zorilla · · Score: 5, Funny

    Radar Tech: "Sir. The car keys, sir. They appear to be... jammed."

    Dark Helmet: "Jammed? Raspberry. There's only one man who would dare give me the raspberry. Lone Starr!"

    --

    It would be cool if it didn't suck.
  11. Re:Medical devices by Rob+Carr · · Score: 5, Informative
    I hope this dampening field isn't messing with medical devices like pacemakers, etc. I would like to think that this stuff is tested for all scenarios but, ...

    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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    This sig seemed like a good idea at the time....
  12. Could be fixed if they spent more on the receiver by Anonymous Coward · · Score: 5, Interesting

    I used to work in a lab where we did some (non-military, non-secret) radio work and it would sometimes cause problems in the car park. The problem seems to be that the receivers in the cars are built "on the cheap" using ceramic resonators rather than quartz crystals, so they are not very selective. That is, rather than being sensitive only to the frequency that the remote is transmitting on, they are also sensitive to adjacent (and not so adjacent) frequencies. They could easily be swamped by a powerful transmitter several MHz away, whereas a better-designed receiver would be imune. So I blame the remote manufacturers.

    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.

  13. Re:Medical devices by Twirlip+of+the+Mists · · Score: 5, Informative

    You don't need to delve into urban legend. Back in 1998, a dozen wireless heart monitors went offline at a major Dallas-area hospital when WFAA-TV turned on its HDTV transmitter for the first time.

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    I write in my journal
  14. Re:Top 10 most stolen cars by rco3 · · Score: 5, Insightful

    Might I suggest you work on your cause-and-effect a bit more?

    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... ... well, OK, welcome to Slashdot!

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    Ce n'est pas un vrai mouvement de robot!
  15. Re:Jams? by kevlar · · Score: 5, Insightful

    The military is operating within its authorized bounds. So are these remotes. The problem is that the military has blankey control over that spectrum, where as your remote can use it, but cannot interfere with anything else. Hence the "must accept any interference" clause.

  16. Re:A story by Holi · · Score: 5, Informative

    In the Navy they use a system called a Red Tag systems. When you are working on equipment and you must kill the power to it you put a Red Tag on it and anyone who violates a red tag suffers severe consequences (up to court martial) So if your dad did not tag the fuse box and decided to work on the radar system (live radar will kill you if you stand in front of the dish) he was not following navy procedure.

    I've seen the outcome when the Red Tag procedure is not followed, it cost a friend of mine his hand.

    --
    Sorry, teleporters just kill you and then make a copy. A perfect, soul-less copy.