YouView recommends radio hams' pet peeve Radio hams with a downer on powerline Ethernet are set to be even more upset by the debut of YouView. The IPTV platform is recommending the networking-over-the-mains technology. YouView is currently running a closed trial of service. Trial support documents seen by The Register recommend punters whose broadband box is more …
Most if not all of those interested in YouViews features will have a FreeSat or Freeview Box/Telly today anyway - and those mostly will not have wireless just a lan port. So likely lots of them will already have powerline today.
(He says goading the nearest Ham with his homeplug av kit )
Sorry guys. I still have a cupboard full of RF diags kit and the Royal Signals training to use it and what do I find from my Devolo adapters? Nothing. Nada. Not a twitch outside of normal variance experienced when the bloody things aren't even switched on or plugged in.
To anyone that complains about powerline networking - if you own a microwave oven or a hairdryer, you are either looking in the wrong place or a massive hypocrite.
There are a number of reports that have been commissioned, and all of them found that when active and connected to a Line Test Network with a 6dB LCL the PLT adapters of all flavours are transmitting at 30+dB above the EN55022B limits, some at 40dB above.
Now, as of October 2011, all newly brought to market PLT devices *must* comply with EN55022B emissions limits, but there is a 6 month window in which the device has to be suspected, investigated, tested and found to be non-compliant.
Whether this regulatory nonsense can continue I don't know, the provisions in the new draft EN50561 standard will supersede EN55022B, but this is still a draft and there is a lot of resistance to the levels allowed because we all know that the adaptive notching approach is not going to be any use unless there are very strong local signals.
A pity that most of the antis here are all ACs and are not prepared to stand up and be counted. The mere fact that Ofcom had to be compelled to release their own PLT test report that was every bit as bad as those protesting had said is indicative that the market is being skewed.
I assume you'll all be telling me that the assault on my ears and the lines down my waterfall displays on HF are a figment of my imagination too.
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"antis here are all ACs and are not prepared to stand up and be counted"
To be frank if the authorities decided the utility of power line communication and the crap it radiates outweighs the utility of HF communications mostly by amateurs in domestic locations where the crap causes the most problem I could live with it and accept standards which allow them to radiate the crap.
What really pees me off is the flouting of the law. Rules is rules and the law is the law except when you have already sold piles of non-compliant illegal crap.
I have recently been involved retesting some old equipment that was never tested properly in the first place. It has been sold for decades without a single reported emission or susceptibility problem but it is far from compliant and is costing thousands to fix and test - mostly a waste of money, but, it has to be done, it is the law. Galling to see non-compliant equipment which definitely causes problems has and continues to be sold.
What is RF diags kit? Your kit or your training is defective.
High speed data transmission requires radio frequency signals and you can't send high speed data down unscreened and untwisted wires without it radiating.
Power line communication modems are broadband radio transmitters, the only way they don't radiate (much) is if your particular mains wiring topology and length happen to be a crap antenna at the frequencies you are interested in.
As for microwave oven - lol. Didn't your training explain the difference between signals with wavelengths of 10s of meters and those of a few centimetres?
Microwave ovens usually operate around 2.4GHz. WiFi operates around 2.4GHz (or 5). Direct interference from leaky microwave ovens is very possible.
Cisco say "Jupiter Research reports 67 percent of all residential Wi-Fi problems are linked to interfering devices, such as cordless phones, baby monitors, and microwave ovens."
Crappy switch mode power supplies might cause interference problems but not at WiFi frequencies. At least microwave ovens are supposed to be tested and comply with radio frequency emission regulations. High speed power line data communication equipment can't be tested because half of the equipment is random house mains wiring different in every installation. Just turning on a light switch or plugging in another appliance could completely change the characteristics or the wiring with regard to it being a radio frequency antenna.
There is no way anyone could claim compliance with CE regulation for High speed power line data communication equipment or honestly put a CE mark on it but they did and do and the authorities won't challenge them to prove compliance because failure and the subsequent recall and refunds for hundreds of thousands of devices would create too much outrage. It is a travesty the idea ever got off the drawing board.
...that home installations differ a great deal. If you have a proper installation probably nothing bad will happen. If you have a bad installation, you will radiate most of the signal.
The other problem is that those powerline modems work at the only frequency range broadcasting is feasible. You cannot broadcast a radio station at, let's say 2.4 GHz because at those frequencies your signal will not be reflected at the ionosphere. You'd have to put a transmitter every 50-200 km, depending on the topography. That is expensive. That's why you only find local channels on those frequencies. (And satellite transmissions, but that's another topic entirely)
So there is very little your microwave oven or diathermy device can interfere with, as frequencies above about 27 MHz are essentially useless for non local broadcasting.
its not the apadapeter is the wioring they use the mans cable is unscreened therefore a massive antenna.
cat 5 is creened twisted pair so you dont get rf leakage, but basically the wiring becomes a network and aan anetanna guess waht in theory it is possibel for your neighbiurs to use your internet conection using devolan adapters . if you think hams are lieing got othe rsgb website and search for plt.
If you haev been in royal signals why you never gt a ham license , ill tell ay why you are not allowed to due to the fact you have not been trained to a higher standard . roayal siganls use equipmet designed for the military , made easy to use for the squaddies.
So, being an arse-hole involves legally transmitting on frequencies you are allowed to use at power levels within your licence conditions does it?
Not one of my neighbours has a house that requires PLT on networking groiunds, I might have some sympathy if there were problems with thick walls and ancient construction, but all the houses around are dry-lined and wooden framed internally so you can get a Cat 5 cable through without the slightest problem.
Intentionally causing or attempting to cause interference to neighbours using *legal* equipment is being an arsehole and as far as I am aware is against the terms of your licence, it would certainly be looked upon very dimly by the authorities. Why don't you grow up and try to resolve the problem amicably instead of making it into a bigger one?
They probably aren't aware that there's anything wrong with the kit they have, it's highly unlikely they will have a clue that you suffer because of it, why not try explaining it to them, you never know, you might actually make a friend and get enough of a social life that sitting in a cramped sweaty shack with your BO and elastoplasted glasses doesn't seem so attractive anymore.
2400 Watts are available from a GPO. If even a small percentage of this is incoming mains power is converted to RF of the 'right sort' then fed back down the power lines then these BPL/PLC/PLT schemes just simply would not exist!
I'm amazed that anarchy hasn't already ruled supreme here.
Forget the interference this stuff causes to other communications users for a moment, for a government to approve a communications system that's so vulnerable--susceptible to inference--is not only a farce but an abrogation of responsibility.
It's not amateurs that users have to worry about, it's terrorists and others of evil intent. For the UK Government to provide a barnyard door for them to walk though at will is essentially criminal irresponsibility.
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Off-topic, but being in a low-signal area I do wish YouView was fully IPTV (i.e. it streamed the Freeview channels over IP and wasn't just a glorified Freeview+Catch-Up TV box).
I'm currently experimenting with a RaspberryPI, XBMC and TVCatchup's XBMC plugin which seems initially to be quite a good solution. Assuming TVCatchup doesn't get ordered to close down for being too useful.
(AC, because I'm admitting I use HPs - I'm not THAT daft...)
We have four HomePlugAV adapters in our house, and I admit they're not pricey ones, so it may well be that they're not "clean" in terms of what they emit.
I'm not proud of us using them, and would get rid of the things in a shot - not just because I want to be friendly to any radio-fans in the area, but mainly because HomePlugAV is just too darn slow (45Mbps-ish on a good day). If I want to copy big files (100MBs) to/from our Synology NAS downstairs, it's faster for me to walk down there and plug a USB drive into the NAS - and, forget about shifting HD video around (which ISTR was one point of HomePlugAV in the first place).
No, I'd much prefer to have Cat5e cabling around the house, but as it's a three-storey, I think I'd have to call in the experts (someone suggested an electrician). I think this one's gonna run and run... :-(
Have you thought about running Cat5e outside the house? I don't know what your set up is but I have my main PC in the attic but TV/WDTV/PS3/modem/router/whatever in the lounge on the ground floor. The cable exits the wall downstairs and goes up the outside of the drainpipe (attached by cable ties) to the attic. Regular Cat5e and no problems in nearly 5 years. I'm sure it will break at some point but the holes are already there and Cat5e is cheap.
+1 for outdoor cat5e. Personally I spent a little more and got some outdoor rated stuff but the regular stuff is probably fine.
I used to have some homeplug adapters, same ones BT give out but they couldn't cope with streaming 1080p and they use a lot of power for what they do.
I realise it's a bit of a hassle to do it yourself but you really don't need to waste your hard earned on an electrician. You can thread cat5 through wall cavities with a stick, a good length of string and somebody on the other end to let you know when they can see the cable. I managed to wire up the attic room in about 3 hours. The most time consuming bit was lifting a few floorboards.
"because they're great and I don't give a shit about radio-hams."
I can understand your view about not giving a shit about radio amateurs as you see them as a threat to your beloved HomePlug system, but the real issue is why someone as ignorant as you (ignorant in these matters anyway) are brought into conflict with the amateurs in the first place.
Clearly, you have no concept whatsoever of how the radio spectrum is divvied up and allocated, for if you had then there's a fair chance that (a) you'd never have bought a HomePlug system in the first place and (b) you'd not have made that selfish comment.
The reason why you've been brought in conflict with amateurs in the first place is that in the last 30 years or so governments have abrogated or substantially scaled down their responsibility for the regulation of the radio spectrum. Under pressure from commercial interests, governments have both outsourced spectrum management and relaxed interference standards which has meant that RF systems now noticeably interfere with each other.
Also, it's meant that BPL/PLC and HomePlug systems have snuck in when they shouldn't have--and they've snuck in because a few 'engineers' were prepared to prostitute their profession to satisfy accountants' desires to cheapen things to a point where now other services--users of the shared radio spectrum--have suffered badly as a consequence through excessive interference.
I can understand your view about not giving a shit about radio amateurs as you see them as a threat to your beloved HomePlug system
I don't see them as a threat at all, I just don't give a shit about them and their whiny ways. Everytime there's an article on Homeplug, out they come, regurgitating some ancient analysis of products no longer on sale or that were - at the time, fully defective - and claiming that products 10 years later shouldn't be on sale as a result. Give me a break, change the record.
Oh, and I stopped reading after your first paragraph.
"Give me a break, change the record."
Not Bloody Likely!!
The more you ignore us, the more annoying we'll become!! BPL/PLC/PLT/HomePlug is an environmental issue--just it's about the radio spectrum environment (but the rules are the same). Like other rabbit Greenies, we'll whinge, annoy and irritate you until all BPL/PLC/PLT/HomePlug spectrum hazards have been regulated out of existence. We 'Greenies' have more persistence, tenacity and resilience than you quiet-lifers, that's why we'll eventually win.
Get used to the fact there's a war in progress and that you spectrum polluters are clearly in our sights.
"Oh, and I stopped reading after your first paragraph."
Correct, you're clueless about Spectrum Management because you've never read anymore than a headline about the subject. Whilst somewhat debased now through government downsizing and outsourcing, but once an important branch of government, Spectrum Management's raison d'être is to protect legitimate users from you spectrum polluters and to see that the radio spectrum is efficiently used by ensuring minimum mutual interference. BPL/PLC/PLT/HomePlug is NOT a legitimate radio service but a spectrum polluter, and thus it will always be a key target of spectrum environmentalism. Spectrum vandals won't get off scot-free! Got that? (Better not forget it either.)
Get it into your thick head that the BPL/PLC/PLT/HomePlug issue is not only a radio amateur issue, it equally concerns many other legitimate users who share the radio spectrum. Moreover, the legitimate users of the spectrum share it in a precise and orderly way and they've done so according to ITU rules for going on a century--unlike BPL/PLC/PLT/HomePlug interference which pays no heed to the rules--any rules, except those of self interest.
I don't approach this argument as an amateur; thus it's unlikely I'll regularly experience the deleterious effects of HF band interference caused by BPL/PLC/PLT/HomePlug, rather I come to it as one who has previously spent time on spectrum management committees. From that perspective, if anything, amateurs could be perceived as more trouble through the less predictable nature and variability of their service but in practice this was never the case.
The fact is that effective spectrum management is and has to be one of the ultimate forms of agreement and cooperation, and over the past century or so this has been mostly the case. Not only is Spectrum Management a highly technical matter but it also involves very different and conflicting issues, both technical and political. Coherent (message-producing) transmitting devices (TV, radio, communications, amateurs etc.) must coexist in close proximity to sensitive receiving devices with almost no mutual degradation being caused to each other's service. Protection from non-message-producing transmitters (noise-producing motors etc.) is axiomatic and thus legally enforceable. It has to be thus if radio communications is to work at all. Add to this mix the intense politics of competing demands for scarce spectrum resources and thus we end up with the highly complex animal that's Spectrum Management.
Into this complex environment comes BPL/PLC/PLT/HomePlug. No, it's nothing like wireless and WiFi which compete with and are allocated spectrum and obey the spectrum management rules as do all other wireless services. Rather, BPL/PLC/PLT/HomePlug obeys no spectrum management rules whatsoever. Intrinsically and by design, it cannot because its signal is fundamentally different and cannot comply on technical grounds (in that it was designed to travel in a bidirectional manner over wires and NOT be radiated). Thus, whilst its signal is coherent within itself, BPL/PLC/PLT/HomePlug is little more than wideband random noise when compared to normal wireless signals that are sent over the highly regulated RF spectrum--i.e.: those which comply with international regulations.
BPL/PLC/PLT/HomePlug was NOT designed to radiate into the spectrum but is does so by virtue of the world's biggest antenna to which it is connected--the powerline grid. The power grid is the means of network distribution for PL/PLC/PLT/HomePlug systems, but to HF signals, thousands upon thousands of miles of power cable strung high into the air are also an enormously effective antenna.
In radio spectrum parlance, BPL/PLC/PLT/HomePlug is a 'DC-to-daylight', broad-spectrum incoherent signal. In electrical engineering parlance it is nothing more than electrical noise, exactly that--unwanted ELECTRICAL NOISE/INTERFERENCE (RFI). Facts are facts, no amount of dressing up can or will ever change that.
No matter, how its advocates try to dress it up, BPL/PLC/PLT/HomePlug cannot be made into anything other than what it is. Attempts at making it comply to certain 'standards' such as restricting its output amplitude/level or notching its output over particularly susceptible bands/frequencies (for example, some amateurs bands) are nothing other than painting over rust, as its signal remains fundamentally incompatible with spectrum management norms.
Nothing can disguise the fact that BPL/PLC/PLT/HomePlug is an extremely wideband, highly complex signal that's rich in high-order harmonics and which spans over many, many octaves. Moreover, as its advocates would try to have us believe, this wideband signal is supposed to coexist within an environment where whole bands are only a small fraction of an octave and where the very narrowband signals contained within them are only a few kHz wide.
To make matters worse, these 'incoherent' noise signals, having been fed into and disseminated by the world's largest antenna, effectively increase the RF spectrum's noise floor right across the planet. Increasing the noise floor has a widespread, profound, and detrimental effect on other radio communication circuits worldwide, as effectively all radio circuits require additional transmitter power to overcome the additional noise. Environmentally friendly it is certainly not!
A simplistic but reasonably realistic analogy of an increased noise floor would be if one were to add some black pigment to a tin of white paint. Later, adding various colour pigments to the now grey paint will still result in one achieving a substantial range of colours, however, all the light and delicate hues will be irretrievably lost. In essence, the signal-to-noise ratio falls for all other legitimate users of the spectrum when BPL/PLC/PLT/HomePlug's interference increases the noise floor across the planet.
In computer vernacular, BPL/PLC/PLT/HomePlug is effectively a virus which pervades most of the HF spectrum and much of the VHF, and the only effective way of totally eliminating it is to kill it off at its source.
Ultimately, there's no other solution other than to get rid BPL/PLC/PLT/HomePlug and replace it with proper engineering and technology. If you and other users of BPL/PLC/PLT/HomePlug-like systems think we RF spectrum environmentalists will eventually go and fade away, then, frankly, you're in for a big shock. If you think we'll stand idly by and let you ruin the spectrum, then think and think again.
We've only just begun, and rest assured you'll lose interest first. Just use proper engineering and we'll leave you completely alone.
Promise.
IP over Power lines was a problem due to the power lines supply power to homes and businesses acting like an antenna. This has been proven to cause interference, and thus has failed in the US.
The product described here uses the person's in house power wires to transmit data, and (similar to X10) is not likely to extend much beyond their power panel, thus not a great concern to Radio Amateurs.
The article should not have implied it was the same system, nor should it have indicated HAMs have a problem with it unless they actually contacted someone of authority in the matter, such as the ARRL or its affiliates.
HAMs have a problem with anything that might possibly use electricity in a modulated form, whether or not it affect SW etc.
Take a look around the Reg forums and all you'll see is anecdotal bollocks about Powerline networking (usually allegedly belonging to someone else) which is CLEARLL the cause of all their poor, poor troubles. It's the equivalent of asking a Parish Council if they'd approve of somebody building any form of manufacturing industry in "their" area - 100% guaranteed, they will vote against. Because they're all a) retired and b) the kind of tosser who stands for a parish council in the first place.
Okay, HAMs aren't quite that bad but they are amateurs with some very dangerous opinions about what causes RF signal modulation and usually no training in proper testing and frequency analysis.
It's like asking trainspotters to comment on a proposed motorway extension.
What's your specialist field, dogged? Mine is physics, electronics, RF propagation, that kind of thing, with a particular interest (from outside) in mass market systems. I am not and never have been a radio ham, RSGB member, whatever, but I do own two oscilloscopes. Now, moving on.
Are readers following BT's slow progress towards faster-than-ADSL broadband? I am, and have been for the last decade or more. (Other ISPs are available, and often better).
To get faster than ordinary ADSL, in a non-cabled area, it's fibre optics from the exchange to the cabinet, then the usual boring old copper the rest of the way to your home, office, etc. The copper bit uses a technology called VDSL - like ADSL, it's radio frequencies down the existing telephone wires. ADSL uses up to roughly medium wave frequencies, but in order to get the extra performance, VDSL needs to make use of more bandwidth, right up to shortwave frequencies. It has to 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 never mind 30Mbit/s. But because the RF spectrum in general is relatively clean, it works reasonably well much of the time (with exceptions).
As it happens the frequencies used by VDSL include the same shortwave frequencies that your beloved hams use.
And with powerline splatter all over those frequencies, not only will they be unusable by the hams, they'll be pretty much unusable for VDSL too. So in a PLT-equipped world you'll likely be stuck with basically ADSL performance until the Internet comes to your door on interference-free fibre. Don't hold your breath on that one.
Now, what was your point again. Or are you just keen on showing your ignorance (it's working well so far).
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What's your specialist field, dogged?
I was Royal Signals. An RF engineer in ugly places. Then I got injured and when I recovered, I worked for Motorola as an RF engineer (in Swindon). From there, I started working on low-level software for diags, then I did some more programming, then some network engineering, then some technical architecture.
But basically, still an RF engineer.
And I promise you, working powerline ethernet (in the home) does not impact HAM frequencies at all. I've tested it exhaustively. Broken, cheap or shoddy kit may do, but still nowhere near as much as a pre-2010 microwave oven.
I can assure you that the early Comtrend PLT devices supplied with BT Vision (which is what started the whole debate within the amateur community) were not notched and produced significant HF digital noise within a radius of a couple of hundred feet at least. I have personal experience of this, and thanks to having a good neighbourly relationship, managed to resolve it amicably.
To be fair, I also had to work with another neighbour to swap a faulty monitor power supply that also wiped out HF, but the problems were both equally bad.
I've had no personal experience of more modern PLT devices, but I have read about problems with these in RADCOM (the monthly RSGB magazine).
Some brands of plasma TV's and cut-price Solar panel installations have also been fingered as polluting the RF spectrum.
I've never had a problem with Microwave ovens at HF, but they don't half screw up stuff in the 2.4GHz region!
Many ex Royal Signals guys are radio hams and in my thirty years of holding an an amateur licence I've never met a bunch of more arrogant guys than members of the RSARS. They generally look down at anyone who wasn't in Royal Signals. Some of the worst operating I've heard has been on RSARS nets especially if some poor soul is having a QSO on a frequency they want to use when it's time for the net to start. They act as though they own the airwaves. I appreciate that I'm tarring a whole group with the same brush but nothing I've heard on the wireless from ex Royal Signals operators makes me think otherwise.
Dogged old chap, you can promise us all you like, but just because in your case you can't detect any interference from PLT does not mean that there is no interference in a great many other places and instances.
Every test result from accredited test laboratories had produced evidence of massive failures in compliance with EMC limits such as EN55022B, failures by as much as 40dB. That translates into 100 times the range of interference that is deemed acceptable, i.e. only interfering over 10m or so, but now apparently it's acceptable to do so over 1km.
The whole premise of power line networking is in error, mains wiring is not sufficiently balanced to suppress radiation when energised in the manner that PLT devices do it. Why do you think that real networking uses cables with 60dB balance between the internal twisted pairs? They don't do it for any reason other than it being essential for reliability and security.
I do wish that you would have a look at the documented evidence of the problem rather than saying that people with decades of experience of working in the EMC industry (and not just on the gamekeeper side either) are wrong.
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