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back to article PLT chair: UK Radio Society is 'living in a dream world'

The chair of the EU committee on powerline networking has responded to the Radio Society's call to arms, claiming that every minute of filibustering pollutes the radio spectrum more. The Radio Society of Great Britain reckons the new standard, prEN 50561‐1, will water down existing requirements, opening the way to greater …

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'Worrying the spooks'

On the other hand, won't the radio waves generated by powerlines reflect the content of the data travelling on the networks, hence providing the spooks with enhanced surveillance capabilities?

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Re: 'Worrying the spooks'

Almost all powerline kit nowadays encrypts traffic with AES or equivalent.

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Re: 'Worrying the spooks'

Ah, so nothing for the spooks there, then. Provided, of course, that it is easy for novices to set up (or better - defaults to secure). Just thinking of how long it's taken for my neighbours to get their wireless properly secured.

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Anonymous Coward

So I can now legally import and sell GPS jammers, etc?

The device itself isn't generating any interference; the antenna it's connected to is. And it's not my fault if the antenna isn't "sufficiently shielded".

Ofcom can't do anything as the device itself isn't a radio transmitter. It's not my fault if some miscreants create a transmitter by connecting it to an insufficiently shielded antenna.

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Re: So I can now legally import and sell GPS jammers, etc?

I was inclined to agree to start then I thought about it some more.

Your GPS jammer is sending the signal to tansmit to the antenna.

The PLT kit is sending data over a cable a side affect of which is the radio waves.

To me that seems an essential difference. The PLT does not want to transmit but transmitting data in this way causes it. It would be the same as saying that using ethernet devices that have cables conneted that do not conform to the cable standards are at fault because of the cables.

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Re: So I can now legally import and sell GPS jammers, etc?

"using ethernet devices that have cables conneted that do not conform to the cable standards are at fault because of the cables."

Have you ever bought a device supplied with an ethernet cable with a lump on it near the end of the cable? I have.

Have you ever bought a device with a power block with a lump on it near the device power socket? You probably have.

That lump is a choke, an RF interference suppression device, included so that when the device is connected to its power source, the innards of the device do not end up radiating RF down its power lead/aerial. The vendors do this because if they didn't, they'd fail to meet the relevant emissions regulations.

If powerline devices had these chokes on them, they might meet the regulations too. But they wouldn't sell many, because they wouldn't work, because they wouldn't be able to transmit (or receive).

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Devil

Re: So I can now legally import and sell GPS jammers, etc?

Quite. We can do a nice line in Jacob's ladders, too. Watching those l-o-n-g sparks repeatedly ascending to heaven is so very restful! And ... it's a work of techno-art, not a transmitter, so we already know that Ofcom will say that "the devices themselves aren't radio transmitters so fall outside their remit" ... whatever the outraged populace around 'em might say about their now total inability to use their TVs, radios, mobiles ... after all, why should we amateurs be the only ones to lose our use of the spectrum? Most un-PC, this discrimination.

This country urgently needs a competent communications regulator, before the ONLY EM spectrum we have disappears forever into a cesspit of Ofcom's "officially sanctioned" pollution. These cretins are a serious embarrassment to anyone with a gram of technological awareness.

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Anonymous Coward

Re: So I can now legally import and sell GPS jammers, etc?

A duck does not wish to defecate, but does so nevertheless. I am sure you are familiar with the phrase"It it walks liek a duck, etc" Surely the same applies to this crappy rubbish, ie PLT.

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Exactly. Or manufacture them (jammers for cell phones, air traffic control, police radio, anything), as long as I ensure that they do not produce interference when antenna is not plugged in.

Sounds as nonsense to me.

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Stop

Where do they get the idea that PLT isn't a radio transmitter

Of course it's a transmitter, it's generating radio frequency energy deliberately on its output pins. The only part of the equation missing is an aerial, and your mains circuit provides that. How long would it take them to jump on pirate radio stations if they weren't using an aerial, but were wiring their transmitter to a bit of pipe.

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Anonymous Coward

Re: Where do they get the idea that PLT isn't a radio transmitter

Of course it's not a transmitter, it has no licence to transmit, and a licence is required to transmit in the frequencies in question.

Therefore it cannot be a transmitter.

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Re: Where do they get the idea that PLT isn't a radio transmitter

So pirate radio, which doesn't have a license, isn't using transmitters because what they have isn't licensed? Sounds like bureaucracy gone mad.

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Anonymous Coward

Re: Sounds like bureaucracy gone mad

Sounds like barrack-room lawyer-reasoning gone mad

fixed

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Re: Where do they get the idea that PLT isn't a radio transmitter

PLT puts out high frequencies onto copper cables. Funnily enough copper cables are great antennas. PLT hence transmits when the copper cable it is running on is unscreened ( the vast majority of mains electric cables).

whether or not it has a licence to transmit doesn't make any difference to the fact it is still transmitting, and more importantly interfering.

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Anonymous Coward

Even if notching sorts the amateur radio folks

Even if notching is done right and does somewhat reduce the interference on the licenced for amateur use bands, such notching does little to remedy the wideband RF interference which (if allowed to continue) will knacker the performance of high speed DSL (which is short wave radio down a telephone line).

Such knackeration will be near impossible to diagnose, especially once widespread. Therefore DSL will increasingly become yesterday's technology.

Sadly the small "save our DSL" part of BT that knows about this is overruled by the more visible (because directly revenue generating?) part of BT that sees PLT as a vital part of the BT Vision product range. Give them five or ten years and the situation will be reversed, the DSL folks will be saying "we told you so".

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Re: Even if notching sorts the amateur radio folks

So in a while when data rate go up, they hit FM broadcasting, Air Traffic Control, PMR, DAB and finally they cause problems with DTT. Then it'll be noticed, but possibly too late.

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Anonymous Coward

Re: Even if notching sorts the amateur radio folks

Our view of BT (openreach) evidently differs...

I see it as BT charge per _connection_, not based on the quality of the connection, so if the line is degraded they still get paid the same amount but have less backhaul overheads... a win-win situation for them and screw the customer!

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Headmaster

A pedant gets grumpy

" ...Chair of the committee defining the standard refutes that, ..."

Am I the only one who is annoyed by seeing the word 'refute' used to actually mean 'deny' or 'disagrees with'?

"...and in many homes the wiring is sufficiently shielded that no interference is generated ..."

Really? I must be living in an old-standard house, as is everybody I know. Where can I find samples of shielded domestic mains power cable?

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Re: A pedant gets grumpy

Absolutely agree. They only say 'refute' because it sounds stronger than 'deny'. Which it is, when used correctly.

As for shielded mains cable that is in the new generation of British housing with larger rooms and modern insulation spec ... oh, wait...

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Anonymous Coward

"Where can I find samples of shielded domestic mains power cable?"

Anywhere that hasn't been rewired since the days of lead-cased mains cable? When was that, fifty years ago, maybe more?

Can't think of any other reason. Even if the cable is in conduit, which is rare in UK domestic premises, it'll likely be plastic.

So any premises with screened mains cable likely has unsafe wiring and needs a rewire?

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Re: "Where can I find samples of shielded domestic mains power cable?"

Actually, you can buy it. It's called "mineral insulated" cable (or Pyro, from one of its trade names, as it's sold to be fireproof). It looks like copper water pipe, it costs an arm and a leg, and not all electricians are competent to install it, because there must be very good earth continuity between its copper outer and the metal pattress box.

However, as a licensed amateur, I would have no objection to PLT, were a competent regulator to mandate the use of Pyro in every installation, and the monitoring of its emissions.

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Re: "Where can I find samples of shielded domestic mains power cable?"

To be fair, FP200 and even boring ole SWA would probably work too. But the point is, this stuff's unnecessary anyway. Install cat5e or cat6 cable. Job done, cheaper than pyro ;-)

And I LOVE MI cable, beautiful stuff to work with when you have time (ie, not on a contract job!)

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Re: "Where can I find samples of shielded domestic mains power cable?"

with the price of copper , can anyone other than the super rich now afford to install Mineral Insulated copper clad (aka pyro) cable ?

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Everybody needs good neighbours

So how do I ensure that my home wiring is sufficiently shielded to prevent any mains-based networking kit I might buy from polluting things for other people?

Can we mitigate this problem by requiring new builds to use shielded wiring and for domestic electrical maintenance work to do the same?

What are the cost implications?

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Re: Everybody needs good neighbours

What are the cost implications?

or more importantly, how good is a cat 5 cable at delivering sufficient juice to my kettle for the coffee required to kickstart my CNS of a morning?

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FAIL

Erm... exactly why do we need PLT anyway?

I'm still not convinced what the business case for PLT actually is? To laxy to install CAT5? Then use WiFi?

G

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Re: Erm... exactly why do we need PLT anyway?

Too lazy to install cat5? More likely running cat5 would involve drilling though and running cable inside walls. A messy, expensivee business. Add to that the fact that a lot of electrical contractors aren't very good at network wiring and you have your answer. Pick up two PLT units and your away in minutes, and any sheds/garages on the same supply can be hooked up too.

Regarding Wifi:it is fine when you have a new build house with plasterboard walls. Try getting a wifi signal through one or two chunky stone internal walls and get back to me. Also untill recently wifi bandwidth and reliability wern't a patch on PLT

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Re: Erm... exactly why do we need PLT anyway?

Where you live in a property where you cannot lay Cat5. (Renting etc) and the walls/structure of the building prevent reliable WiFi Transmission....

hardly difficult that one!

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Anonymous Coward

Re: "untill recently wifi bandwidth and reliability wern't a patch on PLT"

Er, please compare apples with apples.

PLT a few years back didn't have much bandwidth either. If PLT had stayed in the era of the Verran AC Datalink (early 1990s), there'd probably be no problem with wideband RF splatter, because back then, PLT was only offering maybe 9600 baud.

To go faster, each generation of PLT technology transmits on a wider frequency range. We're now in the tens (if not hundreds) of MHz.

Meanwhile the laws of physics remain unchanged. Unbalanced cables radiate at RF, sometimes radiate quite a lot at RF. End of story, whether the PLT vendors and their regulatory stooges like it or not.

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Ru

Re: Erm... exactly why do we need PLT anyway?

I've run cat5 in numerous rental properties where drilling holes in the wall would have been rather frowned upon. Tucking it in under the edge of the carpet, or taping it where the wall meets the floor or ceiling worked just fine. It doesn't take a vast amount of effort to keep it neat and out of the way.

Honestly, how did you people cope before there were any wifi or powerline network devices?

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Re: "untill recently wifi bandwidth and reliability wern't a patch on PLT"

Its also part of physics that a cable/wire connection will be more reliable than wireless.

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Re: Erm... exactly why do we need PLT anyway?

"How did people cope before wifi or pwerline network devices?"

Its only in the last 5 years that VOD directly to your TV/STB took off, not to mention the explosion in smartphones/fodleslabs and the like.

And in my case running a cat5 would have involved either going through newly painted walls or around a fireplace (and AFAIK they don't make cat5 that matches the colour of victorian brick) back to a router who's position is not yet fixed.

And before you say run cables under the carpet, i have hardwood floors.

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WTF?

Re: Erm... exactly why do we need PLT anyway?

Maybe you've never had to deploy a network in a multi-floor building built at a time when builders used proper bricks and mortar rather than the mix of plasterboard, snot and sawdust that prevails nowadays.

My last place of work was in an Edwardian-era building with limited ability to lay additional Cat-5 (listed building, meaning there were some fairly strict restrictions on what could be done inside and out)

- We wanted to lay more Cat-5. We couldn't (see above)

- There was too much attenuation between floors for a single WiFi access point to be of any use (for a variety of reasons said access point would have to live on the ground floor)

The best solution was wireless access points on each floor connected to the network backbone via powerline networking kit.

Don't knock it. It worked.

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Re: Erm... exactly why do we need PLT anyway?

excellent response, characterised the modern western approach to problem solving almost as well as the viz water privatisation (protest) advert 'taking your shit, and putting it in the sea'

i have a slight tech problem that i will solve by causing world+dog a massive problem.

dunderhead!

PLT is a fundamentally stupid idea, it would be nice if it could work. save loads of $$$ and a lot of pissing about with hammer drills in my grade 2 listed longhouse.

but it's broken right out of the box.

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Anonymous Coward

UK Radio Society is 'living in a dream world'

True.

You're just an organisation who tries to get support from a government body to uphold international regulations.

We're businesses, so just piss off.

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Joke

Compromise?

Why don't radio hams just use IM instead?

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Does it even work ?

I'd be willing to bet that PLT only works at all in a minority of homes, due to old or unsuitable mains wiring. It's probably wise before attempting to use this tech to agree with the retailer that he'll refund the full price if your wiring proves unsuitable.

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Re: Does it even work ?

I've run PLT to a barn 100m away from the router on a really rubbish cable with little packet loss. The only thing that really kills it is surge protectors and emf from fridges etc.

Also i bet most house wiring is inspected ressonably regularly, especially since part P came in.

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Anonymous Coward

"i bet most house wiring is inspected ressonably regularly"

Maybe it is on your planet, but where most of us are, it mostly goes for decades without seeing a sparky.

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Re: "i bet most house wiring is inspected ressonably regularly"

I had to explain to my Italian girlfriend that we aren't required to have annual gas safety checks now that we own a house instead of rent. It seemed a little daft, that one, to explain that apparently owning a house makes you somehow more resistant to a gas pipe moving, rupturing or just plain blowing up. I suppose it's pseudo-related to being illegal to adjust the piping in any way without a Corgi certificate to their name (and then I had to explain that most people know what Corgi is, and Gas-Safe is just "the new name for Corgi").

But with electricity? Hell, you don't even need to fit it professionally. The standard is "competency", which is open to interpretation and could cover some guy going to an evening course once. The fire risk is significantly less (though the risk of electric shock is always present, that's more likely to hurt the person tampering than some random joe plugging something with its own fuse in).

The wiring in the house we live in now seems quite recent. There's a proper switch-box and most runs look like new cable and seem to fit new colourings. The only reason for that, though, is that we bought it empty and the previous owner was nothing but a renovator. Looks like they ripped out all the water piping and central heating too and just replaced it with something simpler and from this era. Chances are they will be the same cables in 10 or 15 years time, though, except for stuff that gets extended. Hell, my dad's house has wiring that he installed there himself when he was about 19. The only time you see it is if you pull up a floorboard, and then changing it because it's not using the correct colour code is likely a job that NOBODY would bother to do, or even pay someone to do. And, yes, he has a RCD fusebox now but it was him that wired it in to replace the old wire-fuses! They call them "consumer units" for a reason, you know.

Electrical stuff tends to stay for years on the same cables and connectors. So long as the light switches on when you press the switch, nobody is going to go pulling up floorboards to check it. The only time cable gets *replaced* (rather than extended) is when there's an obvious problem with it, or you have an absolutely empty house that you're either trying to sell or just bought yourself. And that's about the only convenient time to actually do any major electrical work at all.

Hands up how many people here think they know, or have a plan, of where every electrical cable in their house goes, and where old redundant cables lay, and how old those cables are? I'm guessing nowhere near everyone. Now how many have had the cable that brings electricity into the meter shielded or moved by the electricity company since the house was first wired?

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Re: "i bet most house wiring is inspected ressonably regularly"

If someone comes in to change wiring in your house, then they should be Part P registered (ie, registered as 'competent'). It's also theoretically possible to pay the local Council to test and sign it off if the electrician isn't registered, but the response can vary greatly.

However, there is nothing to stop a house owner doing work themselves. It's only when they come to sell that it may be a problem if it's been done badly.

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Re: "i bet most house wiring is inspected ressonably regularly"

Thing is, for fixed wiring "reaonsably regularly" can be every 10 years. On average I bet the average house has some electrical work done that often so any really bad problems will be spotted.

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Re: "i bet most house wiring is inspected ressonably regularly"

the main difference between leccy and gas....

if you leave the leccy alone, it leaves you alone.

but the gas will come looking for you.

yeah i know natural gas not as narsty as town gas etc etc

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Re: "i bet most house wiring is inspected ressonably regularly"

Thing is, for fixed wiring "reaonsably regularly" can be every 10 years. On average I bet the average house has some electrical work done that often so any really bad problems will be spotted.

Agreed. It was only 25 years later, ie this year, when putting in a new hardwood floor in the dining room I discovered that the ground floor ring main wasn't. There's a 30A twin'n'earth hanging loose, must be a length of offcut. Oh, there's another bit. Sparky says, "ah, that's, why I'm getting strange readings on the meter. Your ground floor "ring main" is just one fecking big spur!"

As the resident "user" of the electrical system in this house, I had no idea there was something wrong. It just worked. Luckily, without incident. And no thought or requirement that it ought to be checked. So, from my point of view, Part P actually was useful.

Oh. Yes. None of the cable is shielded in any way. It'll probably be another 25 years before it's looked at again. Unless new regs come in requiring checks or upgrades.

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Re: "i bet most house wiring is inspected ressonably regularly"

"goes on for decades without seeing a sparky" ... well PVC cable can last for quite a while, under resonable conditions.

However the old vulcanized indian rubber stuff was shit, and a sparky was needed to replace it in less than 2 decades of it being installed, unless you liked the thought of your house burning down due to an electrical fire.

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Re: Does it even work ?

and when on surge filters PLT kit doesn't work due to the surge filters filtering out all the RF interference the PLT kit is emitting.

maybe we should make surge filters compulsory on all sockets, that'd screw PLT kit manufacturers. Job done.

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Devil

There's a smokey on your back door

Dear radio HAMs it's 2012. try facebook. skype. IRC if you must.

Never has such a vocal minority been so effective in lobbying against the interests of the rest of us. well perhaps not never. but it's been a while.

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Re: There's a smokey on your back door

You'll need the Hams to do the morse code after the Martians destroy our cities in retaliation for lasering thier planet

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FAIL

Re: There's a smokey on your back door

So old chap, what services do you use that might one day be subject to interference from other systems that are subjected to reduced EMC requirements and hence fail or suffered reduced performance?

The reason that up to now EMC compliance has generally meant that interoperability is widespread is because it has been enforced to the levels determined to be necessary.

The radio spectrum is the only one there is, we can't replace the ionosphere that makes HF radio a worldwide communications resource with one that uses a different frequency range.

EN50561 is about nothing other than allowing inadequately designed installations to perform their stated purpose while risking interference with legitimate users. Allowing the separation of an energising device and the energised network is unacceptable, testing should require it to be terminated in a realistic mains network as found in the majority of real-world domestic installations. CISPR failed to come to an agreement for a PLT standard, as is usual these days the profoundly undemocratic EU decided to pass the question back to a more maleable committee, namely CENELEC, in the expectation that it would do the EC's bidding.

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