back to article Radio hams unite to fight off new powerline comms standard

The Radio Society of Great Britain is mobilising Europe's radio hams in protest against the forthcoming standard for powerline networking, predicting dire consequences if existing standards aren't applied. The society has issued a call to arms (PDF, lots of details) in protest at the new standard for powerline …


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  1. Anonymous Coward
    Anonymous Coward

    RSGB have a point.

    HAMs are far too useful when you need them most to fob off like ofcom and its PLT friends are doing. Time to support this, even if you're not a HAM.

    1. MrXavia
      Thumb Up

      Re: RSGB have a point.

      Totally agree, I will be watching out for a petition, I hope the register gets behind this too so more of us get involved than would otherwise!

  2. Velv

    If Hams were to embrace powerline kit then they could just Skype their "friends" from their attic like the rest of the geeks

    1. Anonymous Coward
      Anonymous Coward

      IF there was a disaster (natural or otherwise) in the area where our skyping geek lived, he might want to contact a ham who might be able to deliver a message to his mother that he was ok. Considering that if the power lines would be down, the internet would be down, and skype does not work too well under those conditions.

      1. Sceptic Tank Silver badge

        Mmmm... HAM.

        ...the internet would be down...

        Well, there's 1x major design goal of the whole thing down the drain for you.

        <== Supposed to still work after some of these.

      2. Maxson

        If the power is out, then the HAM radio wouldn't be intefered with by a device that requires power to transmit, surely?

        In my honest opinion, Powerline adapters have a long way to go yet anyway, I keep considering them as a viable alternative to running cables around the house or Wireless but the tech isn't quite there. It's an asshole move, but if the tech could be there, then I really don't care about HAM Radio.

        1. Intractable Potsherd


          You have heard of this new technology called "batteries", I take it? Ham radios work just fine off them, even if the power is out for miles around.

          1. Tom 13

            Re: @Maxson

            His point, self-admittedly assinine, was that with the power off, there wouldn't be interference from PLT, not that the HAM radios wouldn't work. Of course if it ONLY works when the power is out, there's not much point in being a HAM in the first place.

          2. Graham Wilson
            Thumb Up

            @Intractable Potsherd - Re: @Maxson

            It never ceases to amaze me how ignorant a certain subset of IT types are with respect to electronics. They've an interest in computing, IT and the Internet, which all vitally hinge on electronics working working efficiently and without interference, yet they're totally clueless about the subject, and even more so about the electromagnetic environment in which electronic equipment must work, whether it is a radio receiver or a network switch. The paucity of their education in such matters is overwhelming, so is their selfishness and lack of consideration for others--it's a matter of "use any spectrum we need and to hell with all other legitimate users and services".

            When it comes to terms such as RFI/EMR, Radio Frequency Interference / Electromagnetic Radiation, interference coupling factors, co-siting, protection ratios, intermodulation, dynamic range, blocking interface, CCIR, ITU, spectrum management etc., etc., then their jaws just drop and they start to dribble. They even fail to realise that the term 'bandwidth' comes from the halcyon days of radio when it was about the only form of electronics around.

            They've no idea, that the interference protection that amateurs and most other RF spectrum users seek and demand from regulators is also integrally linked through the same physical mechanisms as is the shielding and interference protection as is used on everything from their motherboards to their WiFi. If, for example, someone ever jammed their petty HomePlug systems by zapping some RF down the line from a nearby power plug, then they'd be totally flummoxed.

            Trouble is that once we had good spectrum management but that in recent years governments have devalued it and or often outsourced its management. With such a lack of interest in spectrum management by the regulators then it's little wonder that the RSGB has taken matters into its own hands.

  3. Anonymous Coward


    i have a sinking feeling that us radio ham-types will be quietly ignored and classed as out-of-date beardy types while the PLT vendors get their way.

    All we can hope for is that some clueless soul joyfully plugs in their new PLT devices and happens to live somewhere that causes mayhem at some government installation - then we *may* see some action.

    Until then OFCOM will wash it's hands of the whole thing.

    1. Anonymous Coward

      Re: well...

      I would have some sympathy except that in the past some (not all I'll admit) radio hams weren't exactly too bothered about their transmissions messing up other peoples TV reception back in the days when TV pre amps weren't very selective about what they pulled in. As long as they were following the law to the letter, if not the spirit then they didn't give a monkeys if half the street couldn't watch Crossroads because Brian was talking to Eric about his prize cucumbers. It does seem to me a case of the boot being on the other foot now.

      1. kissingthecarpet

        Re: well... what a load of rubbish

        So viewers affected were too scared of those psycho radio amateur serial killers to just go and knock on their door and tell them their kit was causing TVI - an offence under (I think) the Wireless Telegraphy Act or similar?

        All the radio amateurs I have known ( I was in a club in early teens) cared about TVI to the point of paranoia.

        What does "As long as they were following the law to the letter, if not the spirit " mean, exactly? We are talking about measurable phenomena here, not opinion after all.

        1. Anonymous Coward
          Thumb Down

          Re: well... what a load of rubbish

          "So viewers affected were too scared of those psycho radio amateur serial killers to just go and knock on their door and tell them their kit was causing TVI "

          And if the guy says "its not me" what were they supposed to do about it? Sure, cal the IBA or whoever was in charge back then who come around when he's not on air, find nothing and go home again.

          "All the radio amateurs I have known ( I was in a club in early teens) cared about TVI to the point of paranoia."

          As I said, it wasn't all , but there were plenty of rogue operators who didn't care. I know - I used to live near one.

          "What does "As long as they were following the law to the letter, if not the spirit " mean, exactly?"

          It means so long as they took measurable measures following the legal guidelines then as far as they were concerned they'd done their bit and if there was still interference , weeeell sucks to be you Mr TV Viewer.

          1. Danny 14

            Re: well... what a load of rubbish

            Mostly you will find it was rogue CB users with burners that caused TVI not the radio hams. Although my CQ days are behind me I do remember getting blamed for TVI when my kit wasnt switch on. The neighbour appologised profusely and went off to the spar car park over the road to have a chat with the various cars that sprouted antennae

      2. JohnMurray

        Re: well...

        Not much you can do to limit interference if the television was using an antenna amplifier that amplified from dc to several hundred MHZ.....

        Little can be done if the tv user wants to receive a distant station using stacked antennas....and the tv cannot stand several volts on its input.

      3. Anonymous Coward

        Re: well...

        A few decades ago I was informed of a TVI problem by my parents' next door neighbour, her elderly mother had an ancient TV set in her bedroom and it was upset by a few watts of VHF SSB.

        I built and tested an appropriate filter and fitted it to her TV feeder. More tests revealed that it cured the problem completely, I even borrowed a linear amp to check it at 10x the power I was using, all interference was gone.

        A few weeks later we had another visit from the old lady's daughter, she was terribly sorry but her mum was complaining again and could I come and see what was wrong. The solution was simple, I simply plugged the filter into the feeder again and this time used some cable ties to make sure it was difficult to remove. It seems that the old lady wanted to know if I was still interfering, so she took out the filter and discovered that I was!

        Modern TV equipment is much less susceptible to interference that the old valve TVs were, and the modulation schemes also resist it rather better. Radio amateurs as a breed are very concerned not to upset their neighbours TV watching, preventing interference is a condition of the licences we have and a lot of effort is made to ensure that we do just that.

      4. G3OCR

        Re: well...

        Back in those days of "crappy pre-amps", I voluntarily kept my beam away from the local communal antenna (which was also getting messed-up TV when a cop, ambulance or the local taxi drove by!), for one month, to give the owners of the communal system plenty of time to replace the "DC-to-Light Blue" pre-amp with something that was designed for TV frequencies.

        I also supplied a band-pass filter to a couple of my neighbouts whose Band 2 antennas and TV front ends were receiving 145MHz and/or 432MHz - as well as Band 2.

        My own transmitters had been checked by a friend who worked for BT (now Ofcom) and was completely clean - the problem was always poor (cheap) design or manufacturing fault in the affected equipment, and my interest was to solve tehse problems, despite them not being caused by any fault of my own.

        More than could be said of some of the illegal (in those days) CB operation which was often carried out with illegal (even now) levels of power and poor knowledge of how to keep transmissions "clean"


    2. JohnMurray

      Re: well...

      As I said when O£COM initiated the free-for-life amateur radio licence: You get what you pay for.

      O£COM is largely an agency dedicated to extracting the last possible penny out of everything it can.

      Doubtless a survey of where its staff work after leaving said agency would be illuminating.

      1. Graham Wilson
        Thumb Up

        @JohnMurray -- Re: well...

        ...or what they were qualified in, or what work they did before joining OFCOM.

        (Knowing who has infiltrated and subverted an organisation is always useful.)

    3. Graham Wilson

      @Chris N - Re: well...

      Perhaps OFCOM might stop washing its hands of the matter if PLT devices didn't work because someone had plugged a jamming device into a nearby GPO.

      It's only through the good grace of radio amateurs and other radio spectrum users that HomePlug/PLT/BPL/PLC hasn't been nuked by unwanted power-line interference long ago.

      HomePlug/PLT/BPL/PLC users are living on borrowed time, methinks.

  4. Gnomalarta

    Not Just Radio Amateurs

    The muddied spectrum will not just effect radio amateurs but anyone or system relying on low level signals on radio frequencies up to around 200MHz. This includes FM broadcasting, radio astronomy, aircraft voice communication, dock, estuary and coastal communications.

    The over-riding problem, one that I don't expect a solution for, is that the radio spectrum is seen merely as a commodity which is overseen by a technically ignorant government .



    1. Spoobistle

      Re: Not Just Radio Amateurs

      The government needs to be convinced that the HF spectrum is a valuable commodity to those who use it for its unique properties, even if it hasn't been "monetised". There are laws about noise pollution and leaving rubbish in your garden, even though it doesn't cost your neighbours anything; PLT interference is a nuisance in the same way, just not so obvious. MPs may be ignorant of technical matters, but they are very used to dealing with complaints about nuisances. They need to know that by letting this slip, they are contributing to the degradation of the radio environment for its responsible users in the same way that nuisance neighbours degrade the aesthetic environment.

      1. Anonymous Coward
        Anonymous Coward

        Re: Not Just Radio Amateurs

        Ham radio is wonderful for inspiring teenagers at school who may be genuinely curious how their mobile phones work. Most of us built a crystal AM receiver as a child. Some of us take that further and start to learn about Morse Code, inductors, capacitors, amplifiers, and more.

        I think it is important to ring fence and preserve this spectrum for the hobbyist and curious. It's like having parks available for children to play in.

        I use the Internet prolific ally. Turns out I am a much better programmer than electrical engineer. But I am very thankful for my younger years learning about electronics from articles and ham club members. And I am firmly against power line Internet that uses unshielded wire for transmission. Ethernet is a superior solution.

    2. Christian Berger

      In fact the big problem is...

      ...that you cannot use any frequency range other than 0-30 MHz for broadcast properly. If you use higher frequencies you won't be able to profit from the ionosphere. Higher frequencies are only useful to local stations and communication links.

      On the other hand, there are multiple solutions for LANs, from WLAN to cheap Ethernet. LANs don't need to use that frequency range.

    3. Anonymous Coward

      Re: Not Just Radio Amateurs

      "a technically ignorant government ."

      Has there ever been any other sort?

      1. Mike Pellatt

        Re: Not Just Radio Amateurs

        I'd say that the coalition in power during WWII was anything but technically ignorant, led by WSC.

        Indeed, they sought out the very best people and actually listened to them. Mostly. It was a vital factor in our victory.

    4. Ploughmans Lunch
      Paris Hilton

      Re: Not Just Radio Amateurs

      And a technically ignorant regulator who cares not a fig for anything but money.

      Paris Hilton for the new Ofcom Boss please.

      She could do a much better job than the inept nitwits running it now.

  5. motoh

    By the end of the day

    We will have a bunch of self-interested, self-informed experts in here, all praising the progress of this half-arsed technology, bemoaning how the technically inept cavemen of the ham field are holding us all back.

    Do yourselves a favor and don't do that. This is horrible, careless design and you're not the smart expert you think you are.

    1. hplasm
      Thumb Up

      Re: By the end of the day

      Couldn't have said it better.

  6. Pete4000uk

    What people forget is that us hams can communicate semi reliably around the world antenna to antenna. No infrastructure in between is needed. And as another poster said, there are a great many other users of the radio spectrum who can have problems caused by noisy devices.

    1. JimmyPage
      Black Helicopters

      Tin foil hat time ?

      you have just neatly encapsulated all the reasons why governments around the world would rather radio hams weren't allowed.

      1. Anonymous Coward

        Re: Tin foil hat time ?

        Er, actually amateur radio exists precisely because of inter-governmental agreement and international treaties through the ITU. Countries that don't want amateur activity make it difficult to get a licence and/or equipment.

    2. Phil O'Sophical Silver badge

      Also remember that most of the spectrum used by radio hams is shared in one way or another. Even if the hams are officially the "primary user" there are still designated "secondary users" who will suffer from this interference. In other cases it is the hams who are the secondary users. It isn't just a minority of geeky types who'll be affected.

      Case in point is the Olympics, where part of the ham radio VHF spectrum is being used by the secondary user (with Ofcom/RSGB agreement) for the duration of the games. Any PLT that upset radio hams in that range would also screw up communications for the games.

      1. Danny 14

        indeed. I shudder to think the amount of noise a PLT wielding tenement block would create.

  7. SJRulez

    When the end comes and technology is no more, we'll need the skills of those HAM's to keep in touch!

    1. Anonymous Coward
      Anonymous Coward

      Quote: "When the end comes and technology is no more, we'll need the skills of those HAM's to keep in touch!"

      Except that barely one in a hundred (or even one in a thousand) of them could actually build a working rig from the scraps lying around in the wastebins of this post technological world. When you can build a complete station from scrap, you might be worthy of special consideration. The rest just buy and use an off the shelf unit with no greater knowledge of its operation that the average iPad user.

      1. Graham Wilson

        Ahh the Anonymous Coward again.

        "Except that barely one in a hundred (or even one in a thousand) of them could actually build a working rig from the scraps lying around in the wastebins of this post technological world."

        Perhaps so, but I'll bet that you'd be lucky to find one in one hundred thousand iPhone users who could give a comprehensive explanation of the working of an iPhone. Let's begin with an easy point--the first of many hundreds of questions: what's the typical bandwidth, sensitivity, selectivity and intermodulation characteristics of a smartphone's GPS system? If you don't know then someone must, otherwise there'd be no working system.

        The fact is that the world is becoming more and more deskilled in hands-on electronics, nevertheless you'd be much better off betting on an experienced amateur than a green electrical engineer just out of uni. It's often forgotten that many amateurs are already technicians, engineers and scientists and that amateur radio is the hobby extension of their work. (You'd be very surprised as to the extent, sophistication and exotic nature of some of the technologies that experienced nerds get involved with.)

      2. G3OCR
        Black Helicopters

        Radios from scrap?

        There's still quite a lot of us left who cherish our "old boat-anchors" and still prefer to use them, or who have modified old "junkers" to work on ham frequencies, and to use modern transmission protocols.

        It's not all "buy the gear and transmit", and even when it is, there's some of us who remember the Cold War times, when we kept even more technically obsolete radios ready for use if "something" destroyed power cables and land-lines (those of my age will understand and recognise the "something")

        The same hams often have generators, and/or standby batteries, often backed by solar, in case of severe floods/winds etc taking out landlines and power lines. They're a volunteer ham group called in England "RAYNET"


        Southport Raynet Controller

  8. Mike G

    This thread smells of stale bovril, burnt electronic circuit boards, sandals, mouldy lofts and pipe tobacco.

    1. motoh

      You smell that? Knowledge, son. Nothing else in the world smells like that.

      I love the smell of knowledge in the morning. You know, one time we had to actually learn tech to use it. When that era was all over, we walked the malls. We couldn't find a one, not one stinkin educated user. The smell, you know, that clean cubicle smell. Smelled like... bullshit.

      Someday progress is gonna end.

      1. Mike G

        Great reply. I totally have respect for the knowledge of radio hams, and any garden shed scientist, but absolute disdain for their unyielding and cantankerous lack of humour. Wherever there is a radio ham thread, there are angry old men, but if they were REAL radio hams they shouldn't be on the interwebs, they should be expressing their indignant rage on shortwave, tootling and beeping frenzied morse to whoever may be listening on another side of an ionosphere bounce.

        1. Aaron Em

          Actually, they're doing both

          Look who's never heard of packet radio...

        2. Gnomalarta

          "but if they were REAL radio hams they shouldn't be on the interwebs, " Good job we DO have sense of humour with silly comments like this flying about!

        3. Mike G

          -10 = point proven

          humourless and angry. I'm deliberately installing powerline adaptors from now on wherever I can, for no other reason than to interrupt these obnoxious old farts

          1. Intractable Potsherd

            @Mike G

            Only one angry, humourless person 'round here, mate, and it seems to be you.

            Disclaimer: I am not, and never have been, a radio ham, but I do use licenced two-way radio equipment for my hobby.

            1. Graham Wilson

              @Intractable Potsherd -- Re: @Mike G

              It's pointless mate, arguing with the absolutely clueless takes time off your life, increases blood pressure, and takes you down to their level.

              Anyway, these cretins are only buying an argument. (The first clue is that they're totally clueless on RF and anything to do with spectrum management.) ...And I'm not into world DXing either.

  9. Anonymous Coward
    Anonymous Coward

    "If you tolerate this..."

    Who writes these? Made me laugh. Believe it or not I was actually downloading the very Manic Street Preachers album this was on!

    Sorry to hijack your thread - please continue.

  10. Ryan 7

    I don't really care about some guy's walkie-talkie,

    but if this stuff interferes with my ADSL then I'm blowing your airport sky high.

    1. Gnomalarta
      Thumb Up

      Re: I don't really care about some guy's walkie-talkie,

      Oh it does that too!

  11. Anonymous Coward

    If you want to do something about this then....

    ...look for the contact details of the UK's CENELEC National Committee man here:

    and write an email to him with your concerns.

    I did so earlier and received a response within half an hour.

  12. Bob Fish

    Why can't we all just get along?

    I have often thought the HAMs as the tin foil hat brigade, simply moaning for moaning's sake, but I am starting to see the light. I am a firm believer that an individual's activities shouldn't interfere with anyone else's so really, why can't the more stringent regulations for the powerline kit be enforced? Surely if they were unworkable then they would be there? If the more stringent regulations were enforced then we could have the powerline kit users (I am one, I think the concept is great) and the radio users living peacefully side by side?

    Is this just too simplistic?

    1. Anonymous Coward
      Thumb Down

      Re: Why can't we all just get along?

      Well a major problem is that if you had equipment that only emitted at the allowable levels in installations where the mains network is very badly balanced, then it is very likely that the PLT gear would work either very badly or not at all. The fundamental problem is that this is a sticking plaster technology for those that will not (or cannot) either install proper network cabling or achieve adequate coverage using wireless networking, the mains network is simply not designed for the purpose it is being used for.

    2. Anonymous Coward
      Anonymous Coward

      Re: Why can't we all just get along?

      Quote: "I am a firm believer that an individual's activities shouldn't interfere with anyone else's..."

      I agree entirely, which is why I, and others, have no sympathy for radio HAMS. HAMs have 'previous' in terms of the interference caused to others.

    3. Graham Wilson

      @Bob Fish -- Re: Why can't we all just get along?

      As with many technically literate people, both amateurs and other radio spectrum users have done a terrible job at explaining to lay people why HomePlug/PLC/BPL/PLT is such a rotten system. Thus it's quite understandable why people who use power line communications often perceive amateurs and other radio spectrum users as obstructionist.

      What's needed are some first class graphical presentations on YouTube etc. that show what actually happens when power line systems come headlong into conflict with coherent radio telecommunications. What's useless are pictures of amateurs glued to a speaker listening to increased noise as it's impossible to illustrate scale in a way that's understood. Rather, we need simple illustrations and demonstrations that show how incredibly weak received radio messages truly are and how easily PLT systems can wipe them out completely.

      Essentially, amateurs and other spectrum users are well behind in the PR stakes. Also, as many institutional spectrum users--military, government. industry users etc.--refuse to speak out about such matters, so it's left to the amateurs to do all the running on this problem. This is very unfair, and amateurs should shame other spectrum users into supporting them. (I know of a case where the military is upset over PLT proposals as it'll significantly increase the noise floor of military communications, yet those within the military knowledgeable about and responsible for radio communications are not allowed to speak out by senior officers/government etc.)

      1. Anonymous Coward
        Anonymous Coward

        "first class graphical presentations on YouTube etc."

        There are (were?) some. You might find some via e.g., where you will also find a facebook group to join.

        Probably my favourite is the one where there are two separate mains systems in an open space, running independently off grid, with no electrical connection between them. Can't see youtube from work so cba providing a link.

        In this video, PLT devices quite happily talk between the two entirely separate mains systems, just using the unauthorised and illegal RF signal propagated in free space from the mains wiring.

  13. Callam McMillan

    PLT is for the lazy

    While I couldn't be personally bothered with the whole HAM business they do have a point when they say that EM disturbances should be minimised whereever possible and that pumping out unnecessary high frequency noise is a bad idea.

    Personally though I believe that PLT is for the lazy, if you can't meet your networking needs with wi-fi, then break out the roll of Cat 6 and do the job properly. Also, should PLT take off in a big way, what happens when you have multiple PLT networks on the same phase of the local power supply from the street transformer - how much noise will be created and how long will it be before some bright spark finds a way to snoop on your internet / get free internet?

    1. Anonymous Coward
      Anonymous Coward


      I'd love to break out the cat 6 and get rid of my PLT connection. Unfortunaty a wife and nicely decorated rooms and a bathroom in the way means it's not going to happen anytime soon unless I plan on a lot of redecorating.

      1. Callam McMillan

        Re: Hmmm

        To be fair that is the catch. In my house I managed to run the cables inside the wall voids and down a conveniently placed exterior drain pipe. I'm not sure if my wife knows yet that the first three months when we buy a new house will involve me taking out the walls, floors and ceilings and rewiring the place! ;)

      2. Anonymous Coward
        Anonymous Coward

        Re: Hmmm

        it's not going to happen anytime soon unless I plan on a lot of redecorating.

        Or divorce :)

      3. G3OCR

        Re: Hmmm

        Errr - Have you heard of WiFi?

        It's a nifty idea - Netwrk signals (including internet!) can be transmitted perfectly legally, and causing no interference outside the allocaed band, just with a couple of cheap boxes. In fact, if you have a reasonably recent laptop, it actually already includes one of these wonderful boxes - free!


    2. Nev

      Re: PLT is for the lazy

      Two words: Rented accommodation.

  14. Anonymous Coward
    Anonymous Coward

    My motion simulator company has yet to receive a single complaint about tainted Chinese baby formula; therefore I can only conclude that it is not a serious problem.

    1. Anonymous Coward

      I suppose next time I'll try not to forget the Joke Alert! icon. Really, there were people who thought... ? Oh, never mind.

  15. Ken Hagan Gold badge

    What does Ofcom regulate, again?

    "Ofcom also argues that it's powerless to do anything, as it only regulates radio transmitters."

    Perhaps Ofcom would like to explain how something that isn't a "radio transmitter" is interfering with radio transmissions. Oh, you meant "intentionally a radio transmitter"? That's OK then. I'll just start breaking the law willy-nilly and when charged will say "but it was merely a side-effect of what I was intending to do" and the beak will chuckle a bit and let me off.

    1. Robert E A Harvey

      Re: What does Ofcom regulate, again?

      IMO Ofcom are as useless a bunch of chairweights as you will find anywhere.

  16. Richard Cartledge

    Powerlines are for power not for signals. They are not designed for that or shielded, it's a horrible kludge of an idea.

  17. Spoobistle

    Lazy government

    PLT is the electromagnetic equivalent of fly-tipping - saves some cowboy the effort of doing the job properly and puts the cost of clearing up onto the people left with the mess. The HF spectrum is a valuable resource for low power long-distance communication, whether hobbyists like hams, or commercial, and should be devoted to this purpose, not abandoned to pollution simply because politicians can't be bothered to listen. I can't help thinking the situation is similar to the canals in the 60s and 70s - they weren't used for cargo so they became rubbish tips, got filled in, built over etc. It took a determined band of objectors to conserve them and now they are appreciated for their amenity and recreational value. We don't know what uses may be developed for HF bands in the future (community broadcasting?) but if they are filled with PLT and SMPSU smog, they won't be any use to anyone.

    Ofcom aren't really the body for this job - they are much more interested in media than tech. Look how much effort they put into nipple-watching on obscure satellite channels. Interference regulation should really be under something like Trading Standards (sales of kit) or Environment (effects).

    1. Callam McMillan

      Re: Lazy government

      I wonder how long it'll be before it is mandated that all electrical cables have to contain an earthed foil shield to stop this EM emission?

    2. Graham Wilson
      Thumb Up

      @Spoobistle -- Re: Lazy government

      Spot on. Absolutely so.

      When governments such as the UK, Australia etc. amalgamated their wireless/spectrum management departments with those of the media into one general media body that handles both (OFCOM, ACMA etc.), then things started to go pear-shaped for spectrum management. Three things stand out:

      1. The outsourcing of RF compliance and RF measurement etc. meant that there was insufficient QA on RF standards, interference measurements got sloppy etc.

      2. These new general departments that combine media and wireless/technical such as Ofcom, ACMA etc., now have a conflict of interest. For example, say the internet lobby wants more PLT, now the newly amalgamated engineers are likely to be overruled on interfere, as spreading the internet by PLC is considered more important. The conflict of issue is now so bad that spectrum management is becoming unworkable.

      3. The amalgamated departments now have fewer engineers per capita. As a consequence, RF/spectrum management no longer has the resources that it once had in a separate department.

      Spectrum users ought to be screaming to high heaven over this issue.

  18. Jim Wilkinson

    Sorry Radio Hams but...

    I wanted to get the interweb to my TV but with the WiFi router and TV at diagonally opposite ends on my house, WiFi was just too weak to hack it. Went for home-plug with some trepidation because of earlier worries about the RF radiation from unscreened power wiring (this idea is at least a couple of decades old now). I haven't measured the noise profile, but have no obvious problems with radios etc. and the TV internet works well.

    I live in a rural area with DVB but not DAB. I'm not surprised DVB is unaffected cos the frequency is too high, but DAB uses the old band 2 TV channel (if I recall correctly) so I'm not sure there's any issue there.

    1. Anonymous Coward
      Anonymous Coward

      Re: Sorry Radio Hams but...

      Here's the deal: if you want to enjoy the benefits of hi-tech then you need to put some effort in (time and elbow grease or cash, it's up to you) to making sure you do the job properly.

      We see this all the time now with technology in other areas. New buildings, for example, have strict regulations over materials quality and crucially environmental impact - everything from planning permission to traffic management to making sure you don't just rip out all that asbestos and dump it and fly tip it. If you want to build a new building or buy a new car then you have to make sure these processes are in place, and you either DIY or you pay someone else to do it for you.

      Most of the time in the digital world, because of the scale of the technology, we don't have to worry about these things (the effects are too small to affect our neighbours), but here the effects are huge. Installing PLT in your home (or on your farm) is polluting the environment in a very antisocial way, albeit invisible to the naked eye.

      If you want to be able to watch lolcatz (or indeed HD Olympics, thank you iPlayer) on your 60" TV in the lounge, but your ADSL modem is on the other side of the house then run some (shielded, please) cable round the outside. It's not hard to DIY or else pay some handyman to do the job for you.

      You'll get guaranteed bandwidth, far better latencies, the security of knowing people can't remotely hack into the signal travelling down the cable and you will be blissfully unaffected by whatever networking technology your neighbours install.

      And it won't polute the local RF environment with your antisocial noise!

      PLT is for lazy, poluting, antisocial types who can't be arsed, or are too cheapskate, to do the job properly.

      As for the companies that make this stuff, have they even heard of social responsibility, sustainable development, environmental impact? Grow a conscience guys.

      1. Graham Wilson
        Paris Hilton

        @A.C. -- Re: Sorry Radio Hams but...

        Same the Greenies are too stupid to sue 'em onto dealing with RF pollution and RF polluters.

        Right, you can't hug the radio spectrum as you can a tree.

        ...Paris Hilton, as I'd reckon she'd be better at the job than Greenies

    2. Danny 14

      Re: Sorry Radio Hams but...

      use a pair of access points with a directional antenna then.

  19. Jim Wilkinson

    And more...

    I forgot to add that the homeplug technical white paper (here: claims that the system was tested with the FCC and was adjusted to ensure minimal interference with the HAM bands. I'm not presenting this as a justification, but it's helpful to realise that the interference issue has been long-standing and there are test results to be perused.

    1. Wize

      Re: And more...

      And how do they test them?

      They power up one unit. On its own. With nothing to talk to.

      When does it make the most noise?

      When two or more units talk to each other and a nice chunk of data is sent.

      Also, it doesn't include the nasty wiring of a house which does not have terminators present in any other type of network cable, causing more RF transmission.

      1. Mike Pellatt

        Re: And more...

        and...... and....... it's done with notching filters in the ham bands. Whose effectiveness will vary depending on the impedance characteristics of the wiring it's connected to.

        and..... and.... some PLT devices don't even meet the (useless) specs for notching.

  20. Anonymous Coward
    Anonymous Coward

    Re: "if this stuff interferes with my ADSL ..."

    DSL broadband (be it ADSL or VDSL aka FTTC or any other flavour) is radio down your telephone wires.

    ADSL uses up to roughly medium wave frequencies. VDSL, in order to get the extra performance, needs to make use of more bandwidth, right up to shortwave frequencies. They do this over a network of cables that was designed (and mostly installed) decades ago with little intention of ever using it for much above 3kHz voice frequency never mind 30Mbit/s short wave RF. But because the RF spectrum in general is relatively clean, it has worked reasonably well much of the time (with exceptions).

    Unfortunately for high speed DSL users and potential users, PLT is wideband RF contamination, pretty much all the way from low frequencies to the short waves and beyond. When telephone wires pick up that contamination, either from your PLT kit or from someone else's in the multiple km between your DSL kit and the far end, your DSL performance will drop through the floor. It may not work at all. You won't know why.

    And no one (not even the handful of competent BT SFI technicians who have a clue) will be able to do much about it, at least not until this PLT stuff is properly regulated (which will mean taking it off the market).

    If you're wondering why the DSL people in the broadband equipment companies aren't kicking up a fuss about this: who is the biggest promoter of PLT in the UK? BT's BT Vision product family. BT's DSL experts in what remains of Martlesham know and understand only too well the technical incompatibilities between widespread use of PLT and widespread use of xDSL, and have done for over a decade [1]. But BT Vision is BT revenue now, and BT revenue now currently outweighs future spectrum unusability. So BT Martlesham now have to keep quiet about what they know, or else. And then there's the likes of Netgear, and others with a foot in both camps. But let's not go there right now.


  21. Anonymous Coward
    Anonymous Coward

    PLT/cable companies

    PLT can get cable companies in trouble in the states. The FCC makes cable companies monitor RF leakage as the are afraid that it can cause interference with FAA radio frequency. If the FCC finds out that the cable companies coaxial is leaking the fine the cable company. I found this out when Comacast knocked on my door ad said the cable amp I was using was leaking RF.

  22. Arthur 1

    Stupid to boot

    The really dumb part about this is that these designs are stupid for the PLT vendors, too.

    Any noise on your power line is running right back into the street (loosely speaking). Right back into the more or less shared medium that is some phase of the power grid cabling, and over into your neighbours. Not a big deal while PLT has low penetration, HUGE deal if you have a 200 unit condo full of the stuff... in a block of 10 condos. At that point the SNR on your line will probably be too low for any meaningful transmission speed making PLT worthless, and passing aircraft will probably end up with radar pictures of Bugs Bunny. Bad and bad.

    1. Anonymous Coward
      Thumb Up

      Re: Stupid to boot

      Interestingly, there is a Bugs Bunny episode wherein Bugs, having been sent to explore the moon, attempts to contact home - only to receive a radio advertisement for Crispy Crunchies:

      Crispy Crunchies are the best

      Look delicious on your vest

      Feed them to unwanted guests

      Stuff the mattress with the rest!

  23. Anonymous Coward
    Anonymous Coward

    Work within the current legal limit, or get out of the business.

    I have some old slow ones and in my use, in my narrow test on that short bit of house wiring the effects on HF were noticeable but small (tested on an SDR that could identify channel changes on the plasma TV two doors way).

    The problem comes in with "X-speed is so yesterday" mentality where sales is driven driven by a "continuous feature increment" at the cost of all other services, users and spectrum content.

    With CAT cable if you want to faster you probably will end up replacing the cable and increasing quality of terminations ensuring the pairs are well balanced not just turning up the power and blasting a greater spectrum down something never intended for, or suited to, data.

    It is probably possible to design and manufacture PLT that works as well as a basic WIFI 20-30mb maybe that does not cause much interference outside the house BUT 200mb+ expected on most mains is just criminal.

    Have the end points sweep until it detects the point at which most power from A gets to B then to ramp down the power to the point it still works.

    Design and manufacture to comply with existing rules that other services, technologies and companies have spent millions trying to meet before the goods are deemed legal to sell.

    If OFCOM or some other regulators are seen to favour industry lobby groups then we really have hit sell out on electrosmogsville earth.

    There are financial interest here rolling over the ideas on compliance we have been working with for years, it will break other RF services from ADSL to DAB and beyond it is not a Ham thing, hams have just the knowledge and vision to see the approaching train.

    If everyone drove around with the windows down and radio blaring while texting and the AA/RAC complained it does not mean the complaint is less valid "just because they have an interest".

  24. G7mzh

    If Ofcam say PLT is legal, how about ...

    I wish to connect an extension speaker from my hifi in the summerhouse at the end of the garden. It's got mains, but no LAN and out of range of the Wifi.

    How about a PLT unit, operating at, say, 1.4 megacycles, feeding into the mains in the house, with a suitable receiver in the summer house? Amplitude modulation will do nicely, and only a couple of watts need be injected.

    Of course, it will comply with the same regulations, to the same extent, as the existing units do. Any interference caused to other equipment is immaterial as they are not part of the PLT-connected system.

    I wonder what OfcoN will say when they start demonstarting their double standards?

  25. The Alpha Klutz

    this is how corporations bypass government

    and they do it especially viciously when its someone elses government.

    globalism is awesome.

    1. Anonymous Coward

      Re: this is how corporations bypass government

      You're absolutely right. In fact, countryization is really just as bad - after all, what's the difference? It's about time we erected trade and information barriers between our town and the next town over. God knows we can't have all of OUR money going to that OTHER town! It'll be the death of us! We must protect our towns from people driving back and forth, and watching television shows made in the other town, or from buying things made in the other town - which just STEAL JOBS from people living in THIS town! All of the towns need to be separate; any other arrangement is due to the government and / or corporations (which are in league when convenient but at odds during other scenarios) who want nothing more than to eat poor peoples' babies! And they can't eat any babies if we all keep separate in our own towns, right?!

      Our town needs to defend itself from all the other towns. Demonstrate against countryization before the MEGAKKKORPS treat the whole country like one big playground!@$!@

      *mouth foams; eyes roll back in sockets*

  26. cortland

    Here we go again

    Imagine the the Police Inspector in your town has a teen aged son. Further imagine that this lad has what we here in the US call a "garage band." And imagine as well (many not need imagine!) that these yobs play loud and obnoxious [insert least favorite genre] into the wee hours and that one then calls the police ...

    "What noise? I don't hear any noise! :

    That has been the response of regulators here in the US about interference from such PLT (we call it BPL) systems as have gone live. Fox running the hen house anyone?

    Luckily, PLT doesn't work very well, the reason being that the majority of its signal radiates (we knew THAT) or is absorbed in neighboring wiring if underground. That's why those folks want to raise the bar (so to speak) high enough to ride under it on a giraffe. They need better signals or they will lose any customers they have.

    Never mind there is a body of law and regulation dating back almost 100 years saying one is NOT allowed to interfere with radio communications and broadcasting (OFCOM even slapped on special rules for London during the Olympics). Never mind that SOME folks still listen to MW and Short Wave radios. There's money to be made. So the PLT vendors are buying a legal remedy to their technical problem -- and one rule can erase dozens. it's so easy ...

    Coming next: Lorries (we call them trucks) burn much less expensive fuel if those bothersome muffler things are removed...

  27. Alan Brown Silver badge

    Not just PLTs

    The amount of wideband crap spewed out by a lot of CFLs is amazing.

    1. Anonymous Coward

      Re: Not just PLTs

      It's remarkable how this kind of thing is a serious problem now, but wasn't during the previous nine hundred years of the use of terrible office florescent lights by the bigatyjillions.

      1. This post has been deleted by its author

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