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Beer Australia Communications

Beer Fridge Caught Interfering With Cellular Network 231

aesoteric writes "A man's backyard beer fridge in Australia has been busted interfering with the cellular network of major carrier Telstra. Engineers used an internally-developed software 'robot' to crawl log files from the network and sent a field team out to pinpoint the cause of the interference."
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Beer Fridge Caught Interfering With Cellular Network

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  • by fuzzyfuzzyfungus ( 1223518 ) on Monday June 03, 2013 @08:12PM (#43901285) Journal

    Incidentally, Australian beer fridges have the honor of being among the first commercially successful applications [wikipedia.org] of refrigeration technology(the principles and some early prototypes were developed elsewhere; but Australia's not-exactly-robust ice-harvesting industry didn't imperil the cost effectiveness of the systems in the way that it did in places that actually have ice). Telstra should turn down whatever RF 'noise' the kids are listening too these days and let Grandpop play what he wants!

    Irrelevant history aside, what kind of dodgy does a motor have to be to generate enough RF to degrade a cell system in the course of performing relatively modest compression duties for a small refrigerator?

    • by Anonymous Coward on Monday June 03, 2013 @08:18PM (#43901313)
      A good lawyer could probably claim that this is a clear cut case of the cellular network being a form of hacking the refridgerator technology, since the fridge tech was around first and therefore has claims to do whatever the cell signals should "work around". If this case were in the US, the lawyer could even pull in the DMCA, 'cause the DMCA specifically destroys any technology made to circumvent an older tech. This cell network is definitely attempting to circumvent the fridge owners right to his technology. Therefore, the cell network should pay $1,000,000 for damages and the CEO should spend a year in prison and have a permanent record for all this hacking of fridge's & then trying to blame the fridges for getting in the way. I don't even care if this is a case of hactivism on the part of the cell network(s) involved, this is unacceptable. UNACCEPTABLE!!
    • by Lehk228 ( 705449 ) on Monday June 03, 2013 @08:20PM (#43901325) Journal
      one with a bad connection turning it into an arc gap transmitter.

      it could have caught fire too so it's good the fault was found
      • I'm just surprised because a brushed motor, which I was assuming this was, acts as a feeble arc gap under normal operation; but presumably had to pass regulatory muster when first manufactured, as well as remaining efficient enough to keep the fridge running, within the power budget provided by a domestic breaker while also putting out enough RF noise to escape(usually sealed to keep the refrigerant in) coolant loop and disrupt the cell towers.

        I would have expected one perturbed enough to be a regulatory is

        • There's arcs and then there's sparks. Well no scientifically there's not, but my point is the amount of RF generated by an arc depends on it's properties just like any matter in physics. A small brushed motor would generate a tiny amount of RF compared to a lightning bolt, or the 15kV or so used by Spark-gap radio transmitters back in the day.

        • by tlhIngan ( 30335 ) <slashdot@worf . n et> on Monday June 03, 2013 @11:50PM (#43902289)

          I'm just surprised because a brushed motor, which I was assuming this was, acts as a feeble arc gap under normal operation; but presumably had to pass regulatory muster when first manufactured, as well as remaining efficient enough to keep the fridge running, within the power budget provided by a domestic breaker while also putting out enough RF noise to escape(usually sealed to keep the refrigerant in) coolant loop and disrupt the cell towers.

          I would have expected one perturbed enough to be a regulatory issue to have popped a breaker, caught fire, or just stopped cooling beer before getting to that point.

          Just a hint at how much RF you need - your cellphone (GSM) typically has a 1W transmitter. Usually, it operates at less than 250mW, and most will probably never ever exceed 500mW. That's all it takes to contact the tower.

          Hell, hams have been able to hit their local repeaters with handhelds that rarely go above 5W, and most cell towers are lot closer. It doesn't take a lot of power to flood the receiver of the tower.

          Anyhow, a 240V 13A socket provides over 3kW of power. The fridge motor really only needs under 1kW. A bad motor can easily drag in another 1kW and still not pop the breaker.

          All one really needs to do is to enclose the motor in some fine mesh which shields the spark gap

          And modern day ITU regulations prohibit operation of a spark gap transmitter because they are very wideband and interfere with lots of communications. This actually proved to be a problem when they wanted to resurrect the transmitters similar to the kind used on the Titanic - the required huge faraday cages to minimize interference.

          • by Teun ( 17872 )
            Weird how you seem to know about electricity and power yet fail to realise 240 V supply was standardised to 230 V in the year 2000...

            Shielding the faulty motor might not work so well, without additional measures the supply cable will happily function as an antenna :)

        • Passed when manufactured. The fridge could be decades old - it's quite possible the brushes were worn down to next-to-nothing. There's no assurance this was a high-quality fridge designed for long life - it could be just the cheapest junk the factories of China could put out capable of making beer colder.

    • by mjwx ( 966435 ) on Monday June 03, 2013 @08:31PM (#43901395)

      Irrelevant history aside, what kind of dodgy does a motor have to be to generate enough RF to degrade a cell system in the course of performing relatively modest compression duties for a small refrigerator?

      It just has to be dodgy enough to interfere with a very specific set of frequencies. In Hellstra's case this is 824â"849 and 869â"894 MHz.

      This is why you are asked to turn off your phone on aircraft, this is what a malfunctioning fridge can do to mobile reception, think about the interference a malfunctioning phone will cause to communications and navigation equipment (which operate on similar frequency ranges to mobile phones).

      But TFA glossed over a very important part of the story, after the offending fridge was deactivated... How did the owner keep his beer cold?

    • by girlintraining ( 1395911 ) on Monday June 03, 2013 @09:03PM (#43901561)

      Irrelevant history aside, what kind of dodgy does a motor have to be to generate enough RF to degrade a cell system in the course of performing relatively modest compression duties for a small refrigerator?

      It doesn't. Any electrical device can emit RF over a broad range of frequencies. Your computer can radiate anywhere from DC to over 5GHz. Your car, especially if it's an electric hybrid, can radiate large amounts of EMR at lower frequencies (not connect it to anything. They would wait up to a year before actually using it, because invariably every single thing that was already pre-existing in the area would be blamed on it, from poor TV reception to baby monitors fuzzing out, etc. The FCC of course investigates these things, and it's become common practice amongst amateur radio operators to simply lead them around to the back of the house and point out the disconnected (inert) antenna, because it's easier than going through the formal process of discovery, and there's a small chance of a false positive and resulting bankrupcy due to fines if that happens.

      It sounds like the problem in Austria is that it's version of 'Part 16' is broken if they're threatening fines over a defective beer fridge. Here in the United States, as long as it's been certified by the FCC, as long as the owner uses it as intended and has not modified it, there is no legal liability that I'm aware of. In this case, such an enforcement action by a mobile phone company would require they prove the owner maliciously is trying to cause interference, or has, through modification or non-intended uses of an otherwise certified device, caused interference, before any fines could be levied. The solution then is for the license holder to work with the owner of the device to come up with a solution.

      Or put another way: The mobile phone company would buy this gentleman a new beer fridge, and haul away the old one for disposal. But it sounds like, in Australia at least, even innocent people who bought a device commercially and used it as intended can be caught in a legal snare that could ruin their lives. Stay classy, Australia.

      • It sounds like the problem in Austria is that it's version of 'Part 16' is broken if they're threatening fines over a defective beer fridge. Here in the United States, as long as it's been certified by the FCC, as long as the owner uses it as intended and has not modified it, there is no legal liability that I'm aware of.

        Not so. In the US, if a Part 15 device is causing interference on licensed bands, the owner of said device is required to correct the interference or stop using the device. Seems like it'

      • by bws111 ( 1216812 )

        I think you mean part 15, and you have it wrong. Part 15 means if your device is interfered with you have no legal recourse, and if your device is causing interference you must stop using it. There is no exemption for working correctly or as certified, and there is no need to show malicious intent. If you are causing interference and do not stop, you will be fined.

      • by mirix ( 1649853 )

        Part 15. I don't think you'd get fines unless you continue to operate once being made aware your device is defective and causing interference, unless it's something blatant (transmitting on licensed/reserved bands, excess power, unregistered device that doesn't meet the regs, etc).

        If it's something that is only bothering one HAM operator, FCC is pretty pokey. If it's interfering with big telcos, or the army, or airplane communication, etc, I imagine the response is pretty swift and somewhat more brutal.

        TFA

    • The motor is likely an AC induction motor, and without brushes,not the problem. I'd check for a dodgy thermostat, myself. With bad / dirty contacts, it could start arcing something fierce before it cut out.

  • How (Score:4, Insightful)

    by Murdoch5 ( 1563847 ) on Monday June 03, 2013 @08:19PM (#43901321) Homepage
    I know a little about radio networks, not a massive amount but enough to get by. The fridge must have been somehow sending out a noise signature which was in tune with the radio conditions of the network. That is what I don't understand, a properly designed radio cellular network should operate outside of the range of frequencies put off by a simple compressor motor that would be a in fridge. So now I have to wonder either the fridge was designed in a very strange manor, or the fridge malfunctioned in a very strange manor or the network was poorly designed. Does anyone have more details as to the exact details of what happened? I would be interested in seeing the hardened data from the logs, fridge and network. I call BS that the fridge was the issue until someone can produce hard log data showing this.
    • Arcing and sparking can release noise across a huge portion of the spectrum. That's how microwaves from 60 to 120 GHz were first made in the 19th century, with a spark gap and resonate cavities.

      • That true but in a residential piece of equipment those risks should be mitigated before they can happen. That being said it's possible.
        • In new-from-the-factory and FCC/equivalent-approved condition, sure. But if it's faulty it might continue to function while internally having developed an internal electrical fault that's causing the noise.

          It wouldn't be the first time something like this has happened either:
          http://news.bbc.co.uk/2/hi/uk_news/england/beds/bucks/herts/8327549.stm [bbc.co.uk]

        • Re:How (Score:4, Interesting)

          by iggymanz ( 596061 ) on Monday June 03, 2013 @09:58PM (#43901815)

          eh? where I come from people plug in their fridge and let it go for 30+ years. what are the brushes of an ac motor going to look like then?

              heck the one I grew up with (from the 60s) my dad took it down to my grandmother's in mid 1990s, he gave it a freon charge right before plugging it in and after my grandmother's death my uncle is using it today. Surely that thing puts out some RFI though who'd notice out there in farmland....

          • by mirix ( 1649853 )

            Fridges use induction motors - no brushes. This provides high reliability and lower noise, at the cost of weight (which is pretty irrelevant in a fridge).

          • The brushes will look the same as they did the first day it was used ... non-existent.

            Unless you need variable speed, brushes are not required in AC motor designs. A fridge generally doesn't use variable speed.

    • Here's another link: http://www.heraldsun.com.au/news/victoria/fridge-fault-causes-telstra-mobile-network-blackouts/story-fni0fit3-1226655474358

      • But that link is also missing all the relevant data to back up the complaint. You can say what ever you want but with out hard numbers and records it means nothing.
    • Re:How (Score:4, Insightful)

      by evilviper ( 135110 ) on Tuesday June 04, 2013 @02:07AM (#43902669) Journal

      The fridge must have been somehow sending out a noise signature which was in tune with the radio conditions of the network

      No, purpose-built transmitters necessarily have a single frequency, but ACCIDENTAL transmitters can crap all over the radio spectrum.

      http://radiohax.wikispaces.com/Spark+gap+transmitter [wikispaces.com]

  • by johnnybogosity ( 2396158 ) on Monday June 03, 2013 @08:24PM (#43901353)
    You want reliable network performance or ice cold beer? That's a tough question.
  • by wadeal ( 884828 ) on Monday June 03, 2013 @08:35PM (#43901417)

    Why can't we have more stories like this? Why does it always have to be something political or an advertisement for a product or the usual MS bashing stories? This title alone is more interesting than any "news" story I've seen on Slashdot in the last year.

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Why can't we have more stories like this? Why does it always have to be something political or an advertisement for a product or the usual MS bashing stories? This title alone is more interesting than any "news" story I've seen on Slashdot in the last year.

      Mr. Wadeal, thank you for choosing our technology blog. In today's competitive market place, we appreciate that you have many choices for keeping yourself abreast of the latest developments within IT and in science. We pride ourselves on honoring our readers, and our continued commitment is to provide you with the accurate, insightful, and timely stories you deserve.

      - Dice

  • The linked article is far more about the internal 'robot' and very little about the beer fridge. While perhaps the intent of the /. post, I was far more interested in how the beer fridge could have caused such an issue. Thankfully, TFA has a link to another, far more interesting, FA [heraldsun.com.au]:

    Telstra engineers say any electric spark of a large enough magnitude can generate radio frequency noise that is wide enough to create blackouts on the 850mHz spectrum that carries our mobile voice calls and internet data.

    Engineers said the motor in the beer fridge was causing the interference.

    It includes an image of said fridge, which looks like something from the 50s/60s (maybe? I don't know, I still have people yelling at me to get off their lawns.) More modern models probably have much better, efficient motors that don't cause this kind of issue.

    Mr Halley said Telstra was increasing its black-spot detectors as Australians flocked to smartphones, and the rapid expansion of services revealed some very odd "ghosts in the machine". [...] These included faulty automatic teller machines, lights and illegal phone and TV antenna boosters.

    No mention of the resolution, but I assume it involved unplugging the fridge. (I wouldn't be surprised if he paid more in electricity for that thing per year than just buying a new, medium-sized fridge.)

    • No mention of the resolution, but I assume it involved unplugging the fridge.

      You will unplug my beer fridge over my cold and lifeless body. This is why we Uhmerkins have guns.

      Hopefully, they bought him a new fridge.

      • by mysidia ( 191772 )

        You will unplug my beer fridge over my cold and lifeless body. This is why we Uhmerkins have guns.

        If need be, the Guvernment can order the local electric company to shut off power to his residence, in order to combat the interference. The lights can be switched off at a safe distance from the pole, without unplugging anything or approaching the residence.

    • I'm really curious about how they could enforce something like making him remove the device. It's not his fault their network is impacted by a completely unrelated device. Did they offer to buy him a new one?

      • by Burdell ( 228580 )

        I don't know about Australia, but in the US, you are responsible if you are causing interference in somebody else's licensed band. Even if you didn't mean to, you are transmitting (noise) on a licensed frequency without a license. If it even looks like it might be because you made some modifications to radio gear, you can be liable for a large fine (and depending on the band possibly jail time).

        I remember a few years ago a convenience store near Miami's airport was closed by the FCC because they had some

      • by mysidia ( 191772 ) on Monday June 03, 2013 @11:31PM (#43902225)

        It's not his fault their network is impacted by a completely unrelated device.

        Once he's been informed of the disturbance his device is creating; he becomes liable if he fails to make it stop.

        Same as if you have a fridge that makes insanely loud noises and creates a disturbance in the neighborhood, or a fridge that shoots fireballs at the neighbor's property.

        The person operating the fridge is liable for the damage, and responsible for the repairs or to cease operation and dispose of their misbehaving equipment.

        • I see the point, it just seems like the article makes it sound like his fridge isn't really malfunctioning; rather it's just really old and happens to blast out interference. It seems to be similar to older microwaves and cordless phones that can interfere with the 2.4Hrtz frequency.

          • by mysidia ( 191772 )

            It seems to be similar to older microwaves and cordless phones that can interfere with the 2.4Hrtz frequency.

            Fortunately 2.4Ghz is a Part15/ unlicensed frequency in the US at least; and some amount of local interference is OK as long as it doesn't emit high powered harmful interference that affects a licensed radio service.

            If the status of 2.4Ghz ever changes - for example, if it becomes a frequency requiring a license -- owners of those devices might have to replace, repair, or cease use of those devi

    • Thankfully, TFA has a link to another, far more interesting, FA [heraldsun.com.au]:

      Gotta hand it to the Herald-Sun. They don't get distracted by irrelevant minutiae such as digital forensics. They cut to the chase!

  • Software robot? (Score:5, Insightful)

    by fahrbot-bot ( 874524 ) on Monday June 03, 2013 @08:49PM (#43901485)

    Engineers used an internally-developed software 'robot' to crawl log files from the network.

    Seriously? I know it's actually stated that way in TFA, but are people that stupid that they can't simply say "program"? In all likelihood, it's probably a 10-line Perl script. (Said as Perl fan, myself.)

      • Sure, but from TFA:

        The "robot" is effectively an algorithm that crawls a database of performance stats collected from equipment across the NextG mobile network.

        So, it searches *a* database of stats collected from remote equipment. How that information is collected isn't mentioned, but "syslog" would be one way. Even if it was collected directly from remote equipment, that could be done by a simple Perl script and a few modules. Certainly nothing even remotely (no pun intended) special about any of that. I did stuff like that before the "Web" was even invented (yes, I'm old). Still, ultimately, it's just a program. Thanks for the link anyway...

        • Agreed, a 'bot' might be nothing special in terms of coding, if you know how, but it *is* established terminology.

          • Agreed, a 'bot' might be nothing special in terms of coding, if you know how, but it *is* established terminology.

            Sure, but given the description in TFA, I'm not sure it really applies. Scanning a local database for data *somehow* inserted from remote sources isn't anything bot-like... I think the interviewees were just trying to up the cool factor. My systems generate reports all the time - yawn. Sometimes my scripts even page/email me - automatically! Wow, I must be some sort of guru! :-)

  • Slightly related, here are a few threads about radio-based baby monitors causing trouble in the ham bands:

    http://www.eham.net/ehamforum/smf/index.php?topic=76680.0 [eham.net]
    http://forums.qrz.com/showthread.php?310670-Bad-Baby-Monitors-on-50-125-FM [qrz.com]
    http://www.techzonez.com/forums/showthread.php/23722-HAM-Radio-and-Eavesdropping!!!!-LONG-ONE [techzonez.com]!

    The first and second one are about hams tracking down the problems. The second goes into great detail on how the user of the monitor was busted by the FCC. The third is from a use

  • by frovingslosh ( 582462 ) on Monday June 03, 2013 @08:53PM (#43901505)
    Now I understand why, after I have 20 or 30 beers, why I have such a hard time finding my way home.
  • Grammar check (Score:2, Offtopic)

    by jabberw0k ( 62554 )

    used an internally-developed software

    That should be, used an internally-developed piece of software. The word "software," like "hardware" or "clothing" is plural. You have a piece of hardware, a piece of clothing, a piece of software -- not "a hardware" or "a clothing" or (ugh) "a software."

  • by abelb ( 1365345 ) on Monday June 03, 2013 @09:50PM (#43901769)
    At least it wasn't the cellular network interfering with the beer fridge. Could have been a disaster.
  • by countach ( 534280 ) on Monday June 03, 2013 @10:50PM (#43902039)

    What I really want to know is what happened to the man's beer. Did Telstra buy him a new fridge or what?

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